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  • 1.
    Abdulrazaq, Erol
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Henrik, Persson
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Syresättning av avloppsvatten: En undersökning av luftningsmetoder på reningsverk2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This essay has been done at the request of Marinfloc AB. It consists of various measurements and experiments investigating the sewage water treatment on a number of different plants. The measurements were executed in the part of the plants called secondary treatment. The objective with secondary treatment is to let micro-organisms remove dissolved and suspended biological and organic matter. The factors which were investigated were which methods are used to oxygenate the sewage water, what level of oxygen saturation is obtained with each method and the power consumption required oxygenating the sewage water. An experiment was carried out on Marinflocs’ own sewage treatment plant with the objective to determine if there is any time difference in oxygenating pure water versus unprocessed sewage water. The conclusion reached was that the four land-based sewage treatment plants that were investigated oxygenate by the same principle. The oxygenation is done by aeration from the bottom in respective aeration tank. The level of oxygen saturation was between 1, 8 – 5, 9 mg oxygen per liter sewage water in all plants. Marinflocs’ current sewage treatment plant uses another principle to oxygenate and its oxygen saturation was measured to a level of 12 mg/l. The experiment on Marinflocs’ own sewage treatment plant concluded that there is a time difference in oxygenating pure water versus unprocessed sewage water. The pure water gets oxygenated faster. 

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  • 2.
    Abou Ghadir, Mohammed
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Aghaei, Zahra
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Life Cycle Analysis and Life Cycle Cost Assessmentof a Single-family house Energy Renovation: Case study Växjö, Sweden2022Independent thesis Advanced level (degree of Master of Fine Arts (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Humans are increasingly influencing the climate and the temperature of the Earth by burning fossilfuels, destroying forests, and raising livestock. This adds massive amounts of greenhouse gases(GHG) to those already present in the atmosphere, amplifying the greenhouse effect andcontributing to global warming. The building sector accounts for a significant amount ofgreenhouse gas emissions. Decarbonizing the building industry can result in significant emissionreductions in the future years. Sweden's energy and climate goals have been updated, and some ofthem include reducing GHG emissions in the building sector, increasing energy efficiency, andmaking electricity production 100 percent renewable. In Sweden, energy renovations in singlefamily houses (SFHs) have the potential to reduce GHG emissions and improve energy efficiency,but the rate of energy renovations remains low because of financial, social, and behavioral barriers.This thesis aims to use LCA and LCC methodologies to assess energy renovations on SFH inVäxjö by combining various combinations of energy efficiency measures (EEMs) to reduce energyuse. The energy performance and eight different renovation scenarios using different EEMs havebeen evaluated for the selected single-family building. To evaluate building renovation measures,we developed a method based on life cycle assessment (LCA) and life cycle cost (LCC) thatincorporates building information modeling (BIM). Five different renovation measures werecombined in eight scenarios in this research, including different thicknesses of thermal insulationfor walls and roofs, triple-glazed windows, and doors with different U-values, air-source heatpumps, mechanical ventilation with heat recovery, and solar photovoltaic. The present cost valuesof renovation measures over 50 years for LCC calculation were calculated. The global warmingpotential (GWP) of each renovation measure was estimated over 50 years using One-click LCA.According to the findings of this thesis project, scenarios 1 and 8 had the lowest and highestreductions in primary energy number, respectively. Scenarios 5, 6, 7, and 8 are the most costeffective in comparison to other scenarios. All scenarios resulted in a reduction in GWP impactfrom an LCA perspective in which scenario 7 resulted in the highest reduction in GWP impact. 

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  • 3.
    Abrahamsson, Louise
    Linköping University, Department of Thematic Studies, Tema Environmental Change.
    Improving methane production using hydrodynamic cavitation as pre-treatment2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    To develop anaerobic digestion (AD), innovative solutions to increase methane yields in existing AD processes are needed. In particular, the adoption of low energy pre-treatments to enhance biomass biodegradability is needed to provide efficient digestion processes increasing profitability. To obtain these features, hydrodynamic cavitation has been evaluated as an innovative solutions for AD of waste activated sludge (WAS), food waste (FW), macro algae and grass, in comparison with steam explosion (high energy pre-treatment). The effect of these two pre-treatments on the substrates, e.g. particle size distribution, soluble chemical oxygen demand (sCOD), biochemical methane potential (BMP) and biodegradability rate, have been evaluated. After two minutes of hydrodynamic cavitation (8 bar), the mean fine particle size decreased from 489- 1344 nm to 277- 381 nm (≤77% reduction) depending of the biomasses. Similar impacts were observed after ten minutes of steam explosion (210 °C, 30 bar) with a reduction in particle size between 40% and 70% for all the substrates treated.  In terms of BMP value, hydrodynamic cavitation caused significant increment only within the A. nodosum showing a post treatment increment of 44% compared to the untreated value, while similar values were obtained before and after treatment within the other tested substrates. In contrast, steam explosion allowed an increment for all treated samples, A. nodosum (+86%), grass (14%) and S. latissima (4%). However, greater impacts where observed with hydrodynamic cavitation than steam explosion when comparing the kinetic constant K. Overall, hydrodynamic cavitation appeared an efficient pre-treatment for AD capable to compete with the traditional steam explosion in terms om kinetics and providing a more efficient energy balance (+14%) as well as methane yield for A. nodosum.

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  • 4.
    Adolfsson Lindahl, Frida
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Edholm, Sigrid
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Hagberg, Felicia
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Holmgren, Niclas
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Källbom, Jacob
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Magnusson, Astrid
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Våtmarkers potential att rena avloppsvatten från läkemedelsrester2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna studie genomfördes på uppdrag av det statliga forskningsinstitutet Formas. Syftet med rapporten var att undersöka hur effektiva våtmarker är som tilläggsrening av avloppsvatten, detta med avseende på reducering av läkemedel samt skadeeffekter på akvatiska organismer. Rapporten baserades på en tidigare studie utförd av Breitholtz et al. (2012) där mätningar av läkemedelshalter samt mortalitet och larvutveckling hos hoppkräftor, Nitocra spinipes, gjordes i fyra olika våtmarker.  De fyra våtmarkerna ligger i Eskilstuna, Oxelösund, Nynäshamn och Trosa. Deras mätningar undersökte mortalitet och larvutvecklingskvot för hoppkräftor i prover utspädda med bräckt vatten vid koncentration avloppsvatten på, 11,25 %; 22,5 %; 45% och 90 %. Proverna för läkemedelshalter späddes inte ut och enbart ett mätvärde per våtmark togs vid inflödet och utflödet.

    I denna rapport undersöktes dessa frågeställningar: (1) Är anlagda våtmarker som tilläggsrening en effektiv metod med avseende på skadeeffekter hos hoppkräftor, (2) till vilken grad reduceras halten läkemedel när våtmarker används som tilläggsrening samt (3) finns det ett samband mellan läkemedelsrester och hoppkräftornas överlevnad?

    För att besvara de tre frågeställningarna genomfördes en metaanalys av data från studien av Breitholtz et al. (2012). Hoppkräftors mortalitet, larvutvecklingskvot (LDR) och koncentration av läkemedel analyserades. Endast mortalitet och larvutvecklingskvot hade tillräckligt med data för utförande av en metaanalys. Läkemedelsanalysen kunde bara göras på en grundläggande nivå.

    Metaanalysen programmerades i MATLAB R2019b, där skillnaden i medelvärdet för mortalitet respektive larvutvecklingskvot beräknades mellan in- och utflöde för de fyra våtmarkerna. Skillnaderna för varje våtmark vägdes samman med invers-varians metoden för att få ett sammanvägt medelvärde. Analysen av läkemedel gjordes på nio läkemedel från Breitholtz et al. (2012). De nio valdes ut då de har pekats ut av Svenska Miljöinstitutet som intressanta ur ett avloppsreningsperspektiv. Excel användes för att göra enklare statistiska analyser mellan in- och utflöde i våtmarkerna. Slutligen gjordes en jämförelse mellan hoppkräftors skadeeffekter och läkemedelshalter genom att ta ut skillnaden i medelvärde mellan in- och utflöde.

    Resultatet från analyserna visade att när våtmarker användes som tilläggsrening minskade mortaliteten hos hoppkräftor för koncentrationerna 11,25 % och 90 % avloppsvatten. För koncentrationerna 22,5 % och 45 % fanns däremot ingen signifikant skillnad i mortalitet. Larvutvecklingskvoten minskade efter våtmarksbehandlingen för alla koncentrationer utom 90 %. Läkemedelshalten minskade i snitt med 30 % mellan inflöde och utflöde i våtmarkerna. För läkemedlen sulfametoxazol och oxazepam kunde dock en ökning ses efter behandling med våtmark. Ingen direkt trend kunde utläsas mellan läkemedelshalt och mortalitet hos hoppkräftor. Detta berodde troligtvis på att andra faktorer och föroreningar påverkade hoppkräftornas mortalitet och larvutvecklingskvot i högre grad än läkemedelshalterna.

    I studien kunde ingen slutsats dras om huruvida tilläggsvåtmarker är en effektiv reningsmetod med avseende på skadeeffekter hos hoppkräftor. Hoppkräftor är bra indikatorer på föroreningar i vattnet, dock är det svårt att bestämma vilka föroreningar som påverkar mest i detta fall. Detta medför att inga direkta samband mellan läkemedel och hoppkräftors mortalitet kunde påvisas i studien. De undersökta läkemedlen reducerades generellt. Eftersom mätningarna gjordes under vinterförhållanden då nedbrytningen i våtmarken är som minst effektiv bör resultatet ses som ett lägsta värde.

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  • 5.
    Ahlström, Marcus
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Online-instrumentering på avloppsreningsverk: status idag och effekter av givarfel på reningsprocessen2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The effectiveness of automated treatment processes within wastewater treatment plants ultimately depend on the quality of the measurement data that is given from the installed sensors. Sensor faults affect the control of the treatment plants and are often the reason different control strategies fail. Today there is a lack of standardized guidelines for how to organize and work with online sensors at Swedish wastewater treatment plants which limits the opportunities for treatment plants to reach their effluent criteria in a resource efficient manner. Much research has been done on ways to optimize control strategies but the role of sensors in the efficiency of the treatment plants has not been given the same level of attention. The purpose of this thesis has been to examine how instrumentation at wastewater treatment plants can be organized and structured to ensure good quality measurement data and to examine how sensor faults affect the treatment process.

    Within the thesis a literature study was conducted where instrumentation at wastewater treatment plants was examined. The effects of sensor faults were examined by simulating a pre-denitrification process in Benchmark Simulation Model no. 2 where off-sets (biases) and drift where added to measurements from different implemented sensors. The simulations showed that positive off-sets (0.10–0.50 mg/l) in an ammonium sensor within a cascaded feedback-loop adds to the energy consumption used for aeration by roughly 4-25%. It could further be shown that all types of faults in a DO sensor in the last aerated basin had significantly larger effect on the treatment process than the same fault in any of the other DO sensors in the preceding basins. If the last aerated basin is designed to have low DO concentrations the DO sensor in that basin is the most important DO sensor to maintain. Positive off-sets (200–1 000 mg TSS/l) in suspended solids sensors used for control of waste activated sludge flow contributed to large increases of ammonia, by 29-464%, in effluent waters. Negative drift in DO sensors showed that significant savings in aeration energy, roughly 4%, was possible to achieve with more frequent maintenance.

    Whether a sensor is affected by a positive or a negative fault, be it off-set or drift, will affect how much and in what way the treatment process will be affected. The study of sensor faults showed that the effect of a positive or a negative fault varied and that the effect on the treatment process was not linear. The effect of a sensor fault on the treatment process will ultimately depend on the implemented control strategy, settings in the controllers and on the controlled process.

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  • 6.
    Ahmad, Arslan
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Brabant Water NV, 5200 BC 's-Hertogenbosch, The Netherlands.
    Evaluation and optimization of advanced oxidation coagulation filtration (AOCF) to produce drinking water with less than 1 μg/L of arsenic2014Report (Other academic)
    Abstract [en]

    Arsenic is an extremely poisonous element. It has been reported to cause contamination of drinking water sources in many parts of the world. The current drinking water permissible limit for arsenic in the European Union is 10 μg/L. The World Health Organization has a general rule that no substance may have a higher lifetime risk of more than 1 in 100,000. However, several studies on toxicity of arsenic suggest that purely based on health effects the arsenic limit of 10 μg/L is not sufficient. The main goal of this research was to develop an efficient arsenic removal technology that could be able to produce drinking water with an arsenic concentration of less than 1 μg/L. For this purpose, an innovative three step technique, Advanced Oxidation - Coagulation - Filtration (AOCF), was investigated through bench-scale and pilot scale experiments in the Netherlands at the water treatment plant of Dorst. Firstly, prior to the investigations on AOCF, the existing arsenic removal at the water treatment plant was investigated. Secondly, through a series of bench-scale experiments, the optimum type of coagulant, its combination dose with the selected chemical oxidant and optimum process pH were determined. Eventually, the partially optimized technique from the bench-scale was implemented at the pilot scale physical model of water treatment plant Dorst where AOCF was evaluated for arsenic removal and its effect on the removal of other common undesirable groundwater constituents. The optimized AOCF technology consistently removed arsenic from groundwater to below 1 ug/L when implemented at pilot scale. The overall effluent quality also remained acceptable. The method is efficient with both types of filtration media tested in this research i.e., virgin sand and metal oxide coated sand, however virgin sand media showed slightly better arsenic removal efficiency.

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    TRITA-LWR Report 2014-1_AOCF
  • 7.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands.;Wageningen Univ & Res WUR, Dept Environm Technol, Droevendaalsesteeg 4, NL-6708 PB Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Heijnen, Leo
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    de Waal, Luuk
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    Battaglia-Brunet, Fabienne
    French Geol Survey BRGM, 3 Ave Claude Guillemin,BP 36009, F-45060 Orleans 02, France..
    Oorthuizen, Wim
    Dunea Duin & Water NV, Pl Verenigde Naties 11-15, NL-2719 EG Zoetermeer, Netherlands..
    Pieterse, Brent
    Dunea Duin & Water NV, Pl Verenigde Naties 11-15, NL-2719 EG Zoetermeer, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    van der Wal, Albert
    Wageningen Univ & Res WUR, Dept Environm Technol, Droevendaalsesteeg 4, NL-6708 PB Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Mobility and redox transformation of arsenic during treatment of artificially recharged groundwater for drinking water production2020In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 178, article id 115826Article in journal (Refereed)
    Abstract [en]

    In this study we investigate opportunities for reducing arsenic (As) to low levels, below 1 mu g/L in produced drinking water from artificially infiltrated groundwater. We observe that rapid sand filtration is the most important treatment step for the oxidation and removal of As at water treatment plants which use artificially recharged groundwater as source. Removal of As is mainly due to As co-precipitation with Fe(III)(oxyhydr)oxides, which shows higher efficiency in rapid sand filter beds compared to aeration and supernatant storage. This is due to an accelerated oxidation of As(III) to As(V) in the filter bed which may be caused by the manganese oxides and/or As(III) oxidizing bacteria, as both are found in the coating of rapid sand filter media grains by chemical analysis and taxonomic profiling of the bacterial communities. Arsenic removal does not take place in treatment steps such as granular activated carbon filtration, ultrafiltration or slow sand filtration, due to a lack of hydrolyzing iron in their influent and a lack of adsorption affinity between As and the filtration surfaces. Further, we found that As reduction to below 1 mu g/L can be effectively achieved at water treatment plants either by treating the influent of rapid sand filters by dosing potassium permanganate in combination with ferric chloride or by treating the effluent of rapid sand filters with ferric chloride dosing only. Finally, we observe that reducing the pH is an effective measure for increasing As co-precipitation with Fe(III)(oxyhydr)oxides, but only when the oxidized arsenic, As(V), is the predominant species in water.

  • 8.
    Ahmad, Arslan
    et al.
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands.;KTH Royal Inst Technol, Dept Sustainable Dev Environm Sci & Engn, KTH Int Groundwater Arsen Res Grp, Stockholm, Sweden.;WUR, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Rutten, Sam
    WUR, Dept Environm Technol, Wageningen, Netherlands..
    Eikelboom, Martijn
    WUR, Dept Environm Technol, Wageningen, Netherlands..
    de Waal, Luuk
    KWR Water Cycle Res Inst, Groningenhaven 7, NL-3433 PE Nieuwegein, Netherlands..
    Bruning, Harry
    WUR, Dept Environm Technol, Wageningen, Netherlands..
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    van der Wal, Albert
    WUR, Dept Environm Technol, Wageningen, Netherlands.;Evides Water Co NV, Schaardijk 150, NL-3063 NH Rotterdam, Netherlands..
    Impact of phosphate, silicate and natural organic matter on the size of Fe(III) precipitates and arsenate co-precipitation efficiency in calcium containing water2020In: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 235, article id 116117Article in journal (Refereed)
    Abstract [en]

    Removal of arsenic (As) from water by co-precipitation with Fe(III) (oxyhydr)oxides is a widely used technique in water treatment. Nevertheless, As removal efficiency appears to be sensitive to the composition of the water matrix. The aim of this study was to gain a deeper understanding of the independent and combined effects of silicate (Si), phosphate (P), natural organic matter (NOM) and calcium (Ca) on arsenate [As(V)] co-precipitation efficiency and the size of Fe(III) precipitates. We found that, in complex solutions, containing multiple solutes and high levels of Ca, (variations in) Si and P concentrations reduce As(V) removal to some extent, mainly due to a decreased adsorption of As(V) onto Fe(III) precipitates. On the other hand, NOM concentrations reduced As(V) removal to a much greater extent, due to possible formation of mobile Fe(III)-NOM complexes that were difficult to remove by filtration. These findings have a great significance for predicting As(V) removal as a function of seasonal and process-related water quality changes at water treatment plants.

  • 9.
    Ahmad, Arslan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. SIBELCO, Ankerpoort NV, Op de Bos 300, 6223 EP, Maastricht, the Netherlands.
    van Genuchten, C. M.
    Department of Geochemistry, Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, Copenhagen, Denmark.
    Deep-dive into iron-based co-precipitation of arsenic: A review of mechanisms derived from synchrotron techniques and implications for groundwater treatment2024In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 249, article id 120970Article, review/survey (Refereed)
    Abstract [en]

    The co-precipitation of Fe(III) (oxyhydr)oxides with arsenic (As) is one of the most widespread approaches to treat As-contaminated groundwater in both low- and high-income settings. Fe-based co-precipitation of As occurs in a variety of conventional and decentralized treatment schemes, including aeration and sand filtration, ferric chloride addition and technologies based on controlled corrosion of Fe(0) (i.e., electrocoagulation). Despite its ease of deployment, Fe-based co-precipitation of As entails a complex series of chemical reactions that often occur simultaneously, including electron-transfer reactions, mineral nucleation, crystal growth, and As sorption. In recent years, the growing use of sophisticated synchrotron-based characterization techniques in water treatment research has generated new detailed and mechanistic insights into the reactions that govern As removal efficiency. The purpose of this critical review is to synthesize the current understanding of the molecular-scale reaction pathways of As co-precipitation with Fe(III), where the source of Fe(III) can be ferric chloride solutions or oxidized Fe(II) sourced from natural Fe(II) in groundwater, ferrous salts or controlled Fe(0) corrosion. We draw primarily on the mechanistic knowledge gained from spectroscopic and nano-scale investigations. We begin by describing the least complex reactions relevant in these conditions (Fe(II) oxidation, Fe(III) polymerization, As sorption in single-solute systems) and build to multi-solute systems containing common groundwater ions that can alter the pathways of As uptake during Fe(III) co-precipitation (Ca, Mg bivalent cations; P, Si oxyanions). We conclude the review by providing a perspective on critical knowledge gaps remaining in this field and new research directions that can further improve the understanding of As removal via Fe(III) co-precipitation.

  • 10.
    Ahmed, Tahmeed
    et al.
    Department of Civil and Environmental Engineering, Islamic University of Technology, 1704, Gazipur, Bangladesh.
    Khan, Md. Habibur Rahman Bejoy
    Department of Civil and Environmental Engineering, Islamic University of Technology, 1704, Gazipur, Bangladesh.
    Ahsan, Amimul
    Department of Civil and Environmental Engineering, Islamic University of Technology, 1704, Gazipur, Bangladesh; Department of Civil and Construction Engineering, Swinburne University of Technology, Melbourne, Australia.
    Islam, Nafis
    Department of Civil and Environmental Engineering, Islamic University of Technology, 1704, Gazipur, Bangladesh.
    El-Sergany, Moetaz
    School of Health and Environmental Studies, Hamdan Bin Mohammed Smart University, 71400, Dubai, UAE.
    Shafiquzzaman, Md.
    Department of Civil Engineering, College of Engineering, Qassim University, 51452, Buraidah, Saudi Arabia.
    Imteaz, Monzur
    Department of Civil and Construction Engineering, Swinburne University of Technology, Melbourne, Australia.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Evaluation of the impacts of seawater integration to electrocoagulation for the removal of pollutants from textile wastewater2024In: Environmental Sciences Europe, ISSN 2190-4707, E-ISSN 2190-4715, Vol. 36, article id 77Article in journal (Refereed)
    Abstract [en]

    Recent textile industry expansion has a major environmental impact if not addressed. Being a water intensive industry, textile manufacturing is usually associated with wastewater management challenges. Electrocoagulation (EC) is recognized as one of the effective solutions to address these challenges. This study aims to investigate the potential of integrating seawater into the EC process for textile wastewater treatment, targeting optimal pollutant removal efficiencies. A simple electrolytic reactor was designed to investigate the removal efficiency of these treatments for chemical oxygen demand (COD), total suspended solids (TSS), turbidity, and color from textile wastewater at different seawater percentages and retention times. Notably, the addition of seawater not only improves the EC process efficiency but also significantly dilutes pollutants, reducing their concentrations. This dual effect enhances removal efficiency and dilution optimizes the treatment outcome. The highest removal efficiencies were achieved for COD (47.26%), TSS (99.52%), turbidity (99.30%), and color (98.19%). However, pH, dissolved oxygen (DO), and electrical conductivity increased with increasing retention times and seawater percentages in the EC process. Moreover, Seawater − EC integration reduces power usage to 15.769 Am−2 and costs approximately 0.20 USD/m3. To assess the effects of the retention times and seawater percentages on pollutant removal from textile wastewater, an analysis of variance (ANOVA) was conducted utilizing the Design-Expert 11 software. The best model obtained using Central Composite Design (CCD) was quadratic for COD (R2 = 0.9121), color (R2 = 0.9535), turbidity (R2 = 0.9525), and TSS (R2 = 0.9433). This study suggests that higher seawater percentages and longer retention times effectively eliminate contaminants but increase ion concentrations.

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  • 11.
    Akdogan, Amanda
    Karlstad University.
    Biologisk slamhydrolys vid Ekeby reningsverk för framtagning av intern kolkälla.2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    Biologisk_slamhydrolys_Amanda_Akdogan
  • 12.
    Akinbomi, Julius
    University of Borås, Faculty of Textiles, Engineering and Business.
    Fermentative hydrogen and methane productions using membrane bioreactors2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The role of energy as a stimulant for economic growth and environmental sustainabilityof any nation has made the focus on green fuels, including fermentative hydrogen (bioH2) andmethane (bioCH4), to be a priority for the World’s policy makers. Nigeria, as the most populousAfrican country, with worsening energy crisis, can benefit from the introduction of the bioH2 andbioCH4 technologies into the country’s energy mix, since such technologies have the potential ofgenerating energy from organic wastes such as fruit waste.Fruit waste was studied in detail in this work because of its great economic andenvironmental potential, as large quantities of the wastes (10–65% of raw fruit) are generatedfrom fruit consumption and processing. Meanwhile, bioH2 and bioCH4 productions involvinganaerobic microorganisms in direct contact with organic wastes have been observed to result insubstrate and product inhibitions, which reduce the gas yields and limit the application of thetechnologies on an industrial scale. For example, in this study, the first experimental work todetermine the effects of hydraulic retention times and fruit mixing on bioH2 production fromsingle and mixed fruits revealed the highest cumulative bioH2 yield to be equivalent to 30% ofthe theoretical yield. However, combining the fermentation process with the application ofmembrane encapsulated cells and membrane separation techniques, respectively, could reducesubstrate and product inhibitions of the microorganisms. This study, therefore, focused on theapplication of membrane techniques to enhance the yields of bioH2 and bioCH4 productions fromthe organic wastes.The second experimental work which focused on reduction of substrate inhibition,involved the investigation of the effects of the PVDF membrane encapsulation techniques on thebioH2 and bioCH4 productions from nutrient media with limonene, myrcene, octanol and hexanalas fruit flavours. The results showed that membrane encapsulated cells produced bioCH4 fasterand lasted longer, compared to free cells in limonene. Also, about 60% membrane protectiveeffect against myrcene, octanol and hexanal inhibitions was obtained. Regarding bioH2production, membrane encapsulated cells, compared to free cells, produced higher average dailyyields of 94, 30 and 77% with hexanal, myrcene and octanol as flavours, respectively. The finalpart of the study, which was aimed at reducing product inhibition, involved the study of theeffects of membrane permeation of volatile fatty acids (VFAs) on the bioreactor hydrodynamicsin relation to bioH2 production. The investigation revealed that low transmembrane pressure of104Pa was required to achieve a 3L h-1m-2 critical flux with reversible fouling mainly due to cakelayer formation, and bioH2 production was also observed to restart after VFAs removal.The results from this study suggest that membrane-based techniques could improve bioH2and bioCH4 productions from fermentation media with substrate and product inhibitions.

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  • 13.
    Albers, Eva
    et al.
    Chalmers University of Technology, Sweden.
    Malmhäll-Bah, Eric
    Chalmers University of Technology, Sweden.
    Olsson, Joakim
    Chalmers University of Technology, Sweden.
    Sterner, Martin
    KTH Royal Institute of Technology, Sweden.
    Myers, Joshua J
    Chalmers University of Technology, Sweden.
    Nylund, Göran M
    University of Gothenburg, Sweden.
    Rupar-Gadd, Katarina
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Abdollahi, Mehdi
    Chalmers University of Technology, Sweden.
    Cvijetinovic, Suzana
    Chalmers University of Technology, Sweden.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Edlund, Ulrica
    KTH Royal Institute of Technology, Sweden.
    Henrik, Paiva
    University of Gothenburg, Sweden.
    Undeland, Ingrid
    Chalmers University of Technology, Sweden.
    Influence of preservation methods on biochemical composition and downstream processing of cultivated Saccharina latissima biomass2021In: Algal Research, ISSN 2211-9264, Vol. 55, article id 102261Article in journal (Refereed)
    Abstract [en]

    Saccharina latissima biomass cultivated along the Swedish west coast was subjectedto four different scalable preservation methods after harvest; freezing, sun-drying,oven-drying and ensiling. Freeze-drying and freezing at -80 °C were also included toprovide dry and wet references. The effects of the different preservation methods onthe composition of Saccharina biomass (on dry weight, DW, basis), and the recoveryas well as properties of high-quality protein, alginate and biogas were evaluated. Sundrying significantly reduced protein, alginate and fatty acid content of the seaweeds and thereby concentrated ash in the biomass compared to the other methods.Protein/amino acids and fatty acids were significantly concentrated in ensiled biomass,while mannitol and laminarin were reduced compared to the other biomasses. Ovendryingand -20 °C freezing affected the composition the least, with lower ash content and alterations in some specific amino and fatty acids. Sun-drying and ensiling resulted in significantly lower protein solubility at high pH compared to the other biomasseswhich translated into the lowest total seaweed protein recovery using the pH-shiftprocess. Highest protein yield was obtained with the freeze-dried reference. Ensilinglead to a significant decrease in the molecular weight of alginate, while sun-dryingcaused a negative effect on alginate by inducing a shift in the guluronic and mannuronic acids composition of alginate. Sun-drying gave the lowest methane yield inthe anaerobic digestion experiments while freezing at -80 °C gave the highest yield,closely followed by freezing at -20 °C and ensiling. To conclude, preservation methods must be carefully chosen to protect the valuable component in Saccharina latissima ,and to achieve an efficient downstream processing ultimately yielding high quality products as part of a seaweed biorefinery.

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  • 14. Alcamán, M. Estrella
    et al.
    Alcorta, Jaime
    Bergman, Birgitta
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences. Stockholm University, Science for Life Laboratory (SciLifeLab).
    Vásquez, Mónica
    Polz, Martin
    Díez, Beatriz
    Physiological and gene expression responses to nitrogen regimes and temperatures in Mastigocladus sp strain CHP1, a predominant thermotolerant cyanobacterium of hot springs2017In: Systematic and Applied Microbiology, ISSN 0723-2020, E-ISSN 1618-0984, Vol. 40, no 2, p. 102-113Article in journal (Refereed)
    Abstract [en]

    Cyanobacteria are widely distributed primary producers with significant implications for the global biogeochemical cycles of carbon and nitrogen. Diazotrophic cyanobacteria of subsection V (Order Stigonematales) are particularly ubiquitous in photoautotrophic microbial mats of hot springs. The Stigonematal cyanobacterium strain CHPI isolated from the Porcelana hot spring (Chile) was one of the major contributors of the new nitrogen through nitrogen fixation. Further morphological and genetic characterization verified that the strain CHP1 belongs to Stigonematales, and it formed a separate Glade together with other thermophiles of the genera Fischerella and Mastigocladus. Strain CHP1 fixed maximum N-2 in the light, independent of the temperature range. At 50 degrees C niJH gene transcripts showed high expression during the light period, whereas the nifH gene expression at 45 degrees C was arrhythmic. The strain displayed a high affinity for nitrate and a low tolerance for high ammonium concentrations, whereas the narB and glnA genes showed higher expression in light and at the beginning of the dark phase. It is proposed that Mastigocladus sp. strain CHPI would represent a good model for the study of subsection V thermophilic cyanobacteria, and for understanding the adaptations of these photoautotrophic organisms inhabiting microbial mats in hot springs globally.

  • 15.
    Alderhell, William
    et al.
    Halmstad University, School of Business, Engineering and Science. Halmstad university.
    Norstedt, David
    Halmstad University, School of Business, Engineering and Science. Halmstad university.
    Water & Cultivate2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
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  • 16.
    Alessandro, Martini
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Biosensorsystem för övervakning av vattenkvalitet2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sweden's drinking water quality is considered to be high partly due to a high quality of the raw water and a well developed sewage infrastructure. Despite this, there is water contamination that could be prevented by installation of a sophisticated early warning system. Some of the major players in the production of drinking water have already invested in different types of early warning systems to ensure drinking water of high quality. There are various forms of early warning systems where automatic monitoring of E. Coli is an interesting alternative. Today's technology allows for this type of measurement, but it is often expensive and sometimes slow.

    This work aims to investigate whether the phenomenon of Extraordinary Optical Transmission (EOT) can be used as the technology of sensors for real-time measurement of indicators of fecal contaminated water. EOT is a transmissions peak which arises due to plasmon resonance. The study was conducted by performing verification measurements by spectrophotometry to detect the EOT. After this biomeasurements where done to show that the surface of the sample can be functionalized to provide the opportunity to choose which analytes should be detected.

    The verifying measurements showed that EOT was detected for one of the five samples where the hole size was 400 nm and the hole spacing was 600 nm. This is due to the high signal strength and to the fact that the phenomenon occurred within the measurement range of the instruments. Samples where designated with the name sPa where s indicates hole size in nm and a hole spacing in nm. The signal strength of the sample 140P600 and 200P600 was too low to determine whether EOT occurred. For samples 400P1000 and 600P1000 calculations showed that EOT occurred outside the measurement range, which meant that EOT could not be measured. Sample 400P600 was chosen to implement bio-measurements wherein the surface was functionalized with biotin Bovine serum albumin (B-BSA) to later bind with fluidMAG Streptavidin. Both B-BSA and streptavidin was bound as shown by the kinetic measurements. 

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  • 17.
    Al-Hazmi, Hussein E.
    et al.
    Gdańsk University of Technology, Poland.
    Mohammadi, Ali
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Hejna, Aleksander
    Poznan University of Technology, Poland.
    Majtacz, Joanna
    Gdańsk University of Technology, Poland.
    Esmaeili, Amin
    University of Doha for Science and Technology (UDST), Qatar.
    Habibzadeh, Sajjad
    Amirkabir University of Technology (Tehran Polytechnic), Iran.
    Saeb, Mohammad Reza
    Gdańsk University of Technology, Poland.
    Badawi, Michael
    Université de Lorraine, France.
    Lima, Eder C.
    University of Rio Grande Do Sul (UFRGS), Brazil.
    Mąkinia, Jacek
    Gdańsk University of Technology, Poland.
    Wastewater reuse in agriculture: Prospects and challenges2023In: Environmental Research, ISSN 0013-9351, E-ISSN 1096-0953, Vol. 236, article id 116711Article, review/survey (Refereed)
    Abstract [en]

    Sustainable water recycling and wastewater reuse are urgent nowadays considering water scarcity and increased water consumption through human activities. In 2015, United Nations Sustainable Development Goal 6 (UN SDG6) highlighted the necessity of recycling wastewater to guarantee water availability for individuals. Currently, wastewater irrigation (WWI) of crops and agricultural land appears essential. The present work overviews the quality of treated wastewater in terms of soil microbial activities, and discusses challenges and benefits of WWI in line with wastewater reuse in agriculture and aquaculture irrigation. Combined conventional-advanced wastewater treatment processes are specifically deliberated, considering the harmful impacts on human health arising from WWI originating from reuse of contaminated water (salts, organic pollutants, toxic metals, and microbial pathogens i.e., viruses and bacteria). The comprehensive literature survey revealed that, in addition to the increased levels of pathogen and microbial threats to human wellbeing, poorly-treated wastewater results in plant and soil contamination with toxic organic/inorganic chemicals, and microbial pathogens. The impact of long-term emerging pollutants like plastic nanoparticles should also be established in further studies, with the development of standardized analytical techniques for such hazardous chemicals. Likewise, the reliable, long-term and extensive judgment on heavy metals threat to human beings's health should be explored in future investigations.

  • 18.
    Al-Hazmi, Hussein E.
    et al.
    Gdańsk University of Technology, Poland.
    Łuczak, Justyna
    Gdańsk University of Technology, Poland.
    Habibzadeh, Sajjad
    Amirkabir University of Technology (Tehran Polytechnic), Iran.
    Hasanin, Mohamed S.
    National Research Centre, Egypt.
    Mohammadi, Ali
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Esmaeili, Amin
    College of the North Atlantic—Qatar, Qatar.
    Kim, Seok-Jhin
    Oklahoma State University, United States.
    Khodadadi Yazdi, Mohsen
    Gdańsk University of Technology, Poland.
    Rabiee, Navid
    Murdoch University, Australia; Macquarie University, Australia.
    Badawi, Michael
    Universit´e de Lorraine, France.
    Saeb, Mohammad Reza
    Medical University of Gdańsk, Poland.
    Polysaccharide nanocomposites in wastewater treatment: A review2024In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 347, article id 140578Article, review/survey (Refereed)
    Abstract [en]

    In modern times, wastewater treatment is vital due to increased water contamination arising from pollutants such as nutrients, pathogens, heavy metals, and pharmaceutical residues. Polysaccharides (PSAs) are natural, renewable, and non-toxic biopolymers used in wastewater treatment in the field of gas separation, liquid filtration, adsorption processes, pervaporation, and proton exchange membranes. Since addition of nanoparticles to PSAs improves their sustainability and strength, nanocomposite PSAs has gained significant attention for wastewater treatment in the past decade. This review presents a comprehensive analysis of PSA-based nanocomposites used for efficient wastewater treatment, focusing on adsorption, photocatalysis, and membrane-based methods. It also discusses potential future applications, challenges, and opportunities in adsorption, filtration, and photocatalysis. Recently, PSAs have shown promise as adsorbents in biological-based systems, effectively removing heavy metals that could hinder microbial activity. Cellulose-mediated adsorbents have successfully removed various pollutants from wastewater, including heavy metals, dyes, oil, organic solvents, pesticides, and pharmaceutical residues. Thus, PSA nanocomposites would support biological processes in wastewater treatment plants. A major concern is the discharge of antibiotic wastes from pharmaceutical industries, posing significant environmental and health risks. PSA-mediated bio-adsorbents, like clay polymeric nanocomposite hydrogel beads, efficiently remove antibiotics from wastewater, ensuring water quality and ecosystem balance. The successful use of PSA-mediated bio-adsorbents in wastewater treatment depends on ongoing research to optimize their application and evaluate their potential environmental impacts. Implementing these eco-friendly adsorbents on a large scale holds great promise in significantly reducing water pollution, safeguarding ecosystems, and protecting human health. 

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  • 19. Ali, Raja H.
    et al.
    Bark, Mikael
    Miró, Jorge
    Muhammad, Sayyed A.
    Sjöstrand, Joel
    Stockholm University, Faculty of Science, Numerical Analysis and Computer Science (NADA). Stockholm University, Science for Life Laboratory (SciLifeLab). Swedish e-Science Research Centre, Sweden.
    Zubair, Syed M.
    Abbas, Raja M.
    Arvestad, Lars
    Stockholm University, Faculty of Science, Numerical Analysis and Computer Science (NADA). Stockholm University, Science for Life Laboratory (SciLifeLab). Swedish e-Science Research Centre, Sweden.
    VMCMC: a graphical and statistical analysis tool for Markov chain Monte Carlo traces2017In: BMC Bioinformatics, E-ISSN 1471-2105, Vol. 18, article id 97Article in journal (Refereed)
    Abstract [en]

    Background: MCMC-based methods are important for Bayesian inference of phylogeny and related parameters. Although being computationally expensive, MCMC yields estimates of posterior distributions that are useful for estimating parameter values and are easy to use in subsequent analysis. There are, however, sometimes practical difficulties with MCMC, relating to convergence assessment and determining burn-in, especially in large-scale analyses. Currently, multiple software are required to perform, e.g., convergence, mixing and interactive exploration of both continuous and tree parameters.

    Results: We have written a software called VMCMC to simplify post-processing of MCMC traces with, for example, automatic burn-in estimation. VMCMC can also be used both as a GUI-based application, supporting interactive exploration, and as a command-line tool suitable for automated pipelines.

    Conclusions: VMCMC is a free software available under the New BSD License. Executable jar files, tutorial manual and source code can be downloaded from https://bitbucket. org/rhali/visualmcmc/.

  • 20.
    Ali, Sabrin
    et al.
    University of Borås, Faculty of Textiles, Engineering and Business.
    Pereira, Elizama
    University of Borås, Faculty of Textiles, Engineering and Business.
    Lustgasemissioner från ryaverket och dess klimatpåverkan: Utvärdering av lustgasmätningar2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sweden's wastewater treatment plant faces several challenges, one of them is the reduction of greenhouse gases. Nitrous oxide is one of these greenhouse gases, which is formed during the purification of wastewater. Nitrous oxide is 300 times more harmful to the climate compared to carbon dioxide. In addition, it affects the depletion of the ozone layer. At present, it is difficult to measure and estimate nitrous oxide emissions, since several simultaneous processes are taking place on large areas. For the operation of sewage treatment plants to take place in an efficient manner and with an extremely small environmental impact, it is important to understand how nitrous oxide is formed and how the formation processes interact with the other treatment processes and operating parameters.

    Emissions of nitrous oxide have been studied at the wastewater treatment plant in Gothenburg. The purpose has been to provide results and measurements from Gryaab AB wastewater treatment plant and to determine which processes give rise to the highest nitrous oxide emissions. Emissions of nitrous oxide emissions have been measured from reject cleaning with the nitrification and denitrification process. Analysis of the results will hopefully be able to help Gryaab AB with further research. As a measurement method, EPA hood measurement was used, which was measured above the water surface in the basins and mobile extractive FTIR was driven around the facility.

    The dominant source of nitrous oxide was found to be formed most in the nitrification process. Where the measurements with hood measurement and sampling showed total emissions corresponding to 1.8 tons of N2O / year. The total nitrous oxide emissions from the biological treatment process showed total emissions corresponding to 3.5 tons of N2O /year.

    As a conclusion, more measurements with different measurement methods and more research should be done to get a better overview of why and how nitrous oxide is formed. And what measures can reduce nitrous oxide emissions. There is a need for further studies with measurements with different measurement methods on Gryaab AB.

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    LUSTGASEMISSIONER FRÅN RYAVERKET OCH DESS KLIMATPÅVERKAN
  • 21.
    Al-Obaidi, Mudhar A.
    et al.
    Technical Institute of Baquba, Middle Technical University, Baquba 32001, Iraq;Technical Instructor Training Institute, Middle Technical University, Baghdad 10074, Iraq.
    Rashid, Farhan Lafta
    Petroleum Engineering Department, College of Engineering, University of Kerbala, Karbala 56001, Iraq.
    Ameen, Arman
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Kadhom, Mohammed
    Department of Environmental Science, College of Energy and Environmental Science, Al-Karkh University of Science, Baghdad 10081, Iraq.
    Mujtaba, Iqbal M.
    Department of Chemical Engineering, Faculty of Engineering and Informatics, University of Bradford, Bradford BD7 1DP, UK.
    Optimizing Reverse Osmosis Feed Spacer Design for Enhanced Dimethylphenol Removal from Wastewater: A Study of Hydrodynamics and Performance Indicators2024In: Water, E-ISSN 2073-4441, Vol. 16, no 6, article id 895Article in journal (Refereed)
    Abstract [en]

    Due to its high pollutant rejection and low energy usage, the spiral wound module of reverse osmosis (RO) process is the most commonly used technology utilised in wastewater treatment. For a spiral wound module, the presence of a feed spacer is important as a key solution to mitigate the concentration polarisation phenomenon, due to disorderly fluid flow, and to improve the mass transfer coefficient. Undoubtedly, improvements in the spiral wound module design, mainly in the symmetrical shape of the feed spacer, can have a significant impact on the cost and probable use of these modules. Despite the wide interest in appraising the impact of feed spacer geometry and orientation on the performance of a spiral wound module for RO process-based water desalination, the hydrodynamics of feed spacers (pressure drop and mass transfer coefficient) and the associated influences of feed spacer design (the height of the feed spacer, the angle of the filaments, and the porosity) on the removal of pollutants from wastewater have not yet been addressed. The current investigation aims to fill this gap by studying the hydrodynamics and design parameters of the selected parallelogram feed spacer type ultrafiltration (UF−3) for the removal of dimethylphenol from wastewater. Using model-based simulation, the impacts of UF−3 feed spacer design parameters, including the height, angle between the filaments (orientation), and porosity on the pressure drop, friction factor, axial flow fluid velocity, mass transfer coefficient, water flux, dimethylphenol rejection, recovery rate, and specific energy consumption are detailed in this study. The study intends to demonstrate the optimum design features of UF−3 feed spacer that should be considered to assure the highest elimination of dimethylphenol from wastewater in addition to the lowest specific energy consumption.

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  • 22.
    Alzeyadi, Ali
    et al.
    Department of Civil Engineering, College of Engineering, Al-Qadisiyah University, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Al-Attabi, Ali W.
    Department of Civil Engineering, College of Engineering, University of Wasit, Iraq.
    Mosa, Muhanad H.
    Department of Mechanical Engineering, College of Engineering, Al-Qadisiyah University, Iraq.
    Assessing the effectiveness of low-cost materials to act as filter media for phosphate sorption2023In: Al-Qadisiyah Journal for Engineering Sciences, ISSN 1998-4456, Vol. 16, no 4, p. 253-258Article in journal (Refereed)
    Abstract [en]

    In this research, an assessment was conducted for several materials to examine their efficiency for sorption phosphate and their potential use as filter media. This work focuses on seeking materials that can achieve high, rapid, and robust phosphate retention. To assess the phosphate removal efficiency, batch-mode testing was conducted. The capability of the selected materials for effectively removal the phosphate is largely influenced by their inherent properties. Therefore, this research determines the effectiveness of the material by examining its physical and chemical characteristics. The selection method for these materials was guided by the understanding that the sorbents that have the most effective behavior for phosphate tend to contain easily soluble Ca/Mg compounds or Fe/Al hydroxides. The findings of the batch experiments demonstrated that material such as Bio ash (Bio-A) exhibited superior phosphate removal performance throughout the entire duration of the experiments. In contrast, materials calcium carbonate (C-C) and conventional silica (C-S) displayed relatively poor removal performance compared to Bio-A.

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  • 23.
    Ambjörnsson, Linn
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Ewald, Katti
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Johansson Kling, Erika
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Larsson, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Marie, Selenius
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Elin, Svedberg
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Purification of arsenic contaminated water using ferrihydrite with consideration to current circumstances in Burkina Faso2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Ferrihydrite in a suspension has been studied as a solution for purification of arsenic contaminated water. Many development countries, amongst them Burkina Faso, have arsenic in their groundwater and the current methods for purification are too expensive. Measurements have shown extremely high levels of arsenic in the groundwater in several places in Burkina Faso. Since the availability of surface water is limited, the groundwater is still used as drinking water.

     

    A suspension of ferrihydrite has capacity to adsorb arsenic in water due to its chemical characteristics. Small-scale laboratory work with ferrihydrite suspensions has been performed in parallel in Uppsala, Sweden, and Ouagadougou, Burkina Faso. To purify the water with regard to the economical and practical circumstances in Burkina Faso, a column with safety filter was made out of simple materials such as plastic bottles, plastic tubes and glass wool. The contaminated water was flowing upwards through the column to prevent the filter from clogging.

     

    In Uppsala it was discovered that a 1 L ferrihydrite suspension containing 10 g ferrihydrite can adsorb 0.7 g arsenic while it was shaken and centrifuged well. In Ouagadougou it was possible, in the setup, to clean 2 L arsenic contaminated water with the concentration of 100 µg/L. The conclusions from the experiments in this project are that ferrihydrite can adsorb arsenic in contaminated water but that the setup used needs to be further evaluated and developed

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  • 24.
    Ammenberg, Jonas
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Miljöarbete i företag2023In: Miljöteknik: för en hållbar utveckling / [ed] Jonas Ammenberg, Olof Hjelm, Lund: Studentlitteratur AB, 2023, 2, Vol. Sidorna 163-177, p. 163-177Chapter in book (Other academic)
    Abstract [sv]

    Så här långt i bokens tredje del har angreppssätt för att hantera miljöfrågor berörts ur olika perspektiv. Det har handlat om en historisk tillbakablick, övergripande strategier och produktutveckling, men också om systemperspektiv och miljösystemanalys. Boken har i många avseende samhällsfokus, men mycket av det som berörs har stor relevans för och inverkan på enskilda företag och andra typer av organisationer. De måste ofta inom ramarna för sin verksamhet och organisation hantera miljöfrågor som berör dem. Eftersom det kan vara nyttigt att försöka se situationen ur ett företagsperspektiv beskrivs i detta kapitel kortfattat hur miljöarbete kan se ut i dag i större svenska industriföretag.

  • 25.
    Ammenberg, Jonas
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Miljöhistorisk översikt2023In: Miljöteknik: för en hållbar utveckling / [ed] Jonas Ammenberg, Olof Hjelm, Lund: Studentlitteratur AB, 2023, 2, Vol. Sidorna 111-114, p. 111-114Chapter in book (Other academic)
    Abstract [sv]

    Detta sjätte kapitel inleder bokens tredje del, som handlar om olika angreppssätt för att hantera miljöproblem. Kapitlet bidrar med en kort historisk översikt för att illustrera hur både synen på miljöfrågorna och åtgärderna förändrats över tid. Avslutningsvis summeras olika strategier för att jobba med miljöfrågor.

  • 26.
    Ammenberg, Jonas
    et al.
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Thuresson, Leif
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Hjelm, Olof
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Globala miljöproblem2023In: Miljöteknik: för en hållbar utveckling / [ed] Jonas Ammenberg, Olof Hjelm, Lund: Studentlitteratur AB, 2023, Vol. Sidorna 39-70, p. 39-70Chapter in book (Other academic)
    Abstract [sv]

    I detta kapitel beskrivs några betydande miljöproblem av global karaktär. Det handlar närmare bestämt om klimatförändringar, uttunning av ozonskiktet, minskad biologisk mångfald och användning av naturresurser. Syftet är att du som läsare bättre ska förstå vad som kännetecknar problemen, vad i samhället som orsakar dem, rådande trender och möjliga åtgärder.

  • 27.
    Anbalagan, Anbarasan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    A passage to wastewater nutrient recovery units: Microalgal-Bacterial bioreactors2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In recent years, the microalgal–bacterial process has been considered to be a very attractive engineering solution for wastewater treatment. However, it has not been widely studied in the context of conventional wastewater treatment design under Swedish conditions. The technology holds several advantages: as a CO2 sink, ability to withstand cold conditions, ability to grow under low light, fast settling without chemical precipitation, and reducing the loss of valuable nutrients (CO2, N2, N2O, PO4). The process also provides the option to be operated either as mainstream (treatment of municipal wastewater) or side stream (treatment of centrate from anaerobic digesters) to reduce the nutrient load of the wastewater. Furthermore, the application is not only limited to wastewater treatment; the biomass can be used to synthesise platform chemicals or biofuels and can be followed by recovery of ammonium and phosphate for use in agriculture.

    In the present study, the feasibility of applying the process in Swedish temperature and light conditions was investigated by implementing microalgae within the activated sludge process. In this context, the supporting operational and performance indicators (hydraulic retention time (HRT), sludge retention time (SRT) and nutrients removal) were evaluated to support naturally occurring consortia in photo-sequencing and continuous bioreactor configuration. Furthermore, CO2 uptake and light spectrum-mediated nutrient removal were investigated to reduce the impact on climate and the technical challenges associated with this type of system.

    The results identified effective retention times of 6 and 4 days (HRT = SRT) under limited lighting to reduce the electrical consumption. From the perspective of nitrogen removal, the process demands effective CO2 input either in the mainstream or side stream treatment. The incorporation of a vertical absorption column demonstrated effective CO2 mass transfer to support efficient nitrogen and phosphorus removal as a side stream treatment. However, the investigation of a continuous single-stage process as the mainstream showed a requirement for a lower SRT in comparison to semi-continuous operation due to faster settlability, regardless of inorganic carbon. Furthermore, the process showed an effective reduction of influent phosphorus and organic compounds (i.e. COD/TOC) load in the wastewater as a result of photosynthetic aeration. Most importantly, the operation was stable at the temperature equivalent of wastewater (12 and 13 ˚C), under different lighting (white, and red-blue wavelengths) and retention times (6 and 1.5 d HRT) with complete nitrification. Additionally, the biomass production was stable with faster settling properties without any physiochemical separation.

    The outcomes of this thesis on microalgal–bacterial nutrient removal demonstrates that (1) photosynthesis-based aeration at existing wastewater conditions under photo-sequential and continuous photobioreactor setup, (2) flocs with rapid settling characteristics at all studied retention times, (3) the possibility of increasing carbon supplementation to achieve higher carbon to nitrogen balance in the photobioreactor, and (4) most importantly, nitrification-based microalgal biomass uptake occurred at all spectral distributions, lower photosynthetic active radiation and existing wastewater conditions.

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  • 28.
    Anbalagan, Anbarasan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Indigenous microalgae-activated sludge cultivation system for wastewater treatment2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The municipal wastewater is mainly composed of water containing anthropogenic wastes that are rich in nutrients such as carbon, nitrogen and phosphorous. The cost for biological treatment of wastewater is increasing globally due to the population growth in urban cities. In general, the activated sludge (AS) process is a biological nutrient removal process used in wastewater treatment plants (WWTPs). The AS is composed of different microorganisms in which bacteria play a crucial role in wastewater treatment (WWT). During the process, air is bubbled to supply oxygen and methanol is added to improve nitrogen removal, which is released as a gas. Phosphorous is removed in the expense of precipitation chemicals. Altogether, the current process requires electrical energy, precipitation chemicals, handling of excess sludge and it emits carbon dioxide (CO2) as a by-product. This process is still in practise in the WWTPs since 1914 although numerous modifications are implemented to meet the stringent regulations in the European Union and globally.

    Microalgae are microorganisms that perform photosynthesis like plants. They are green and reproduce fast using available nutrients (nitrogen and phosphorous) and CO2 from their environment in the presence of light. As a result of photosynthesis, oxygen is released as waste gas. The synthesised oxygen during this process can be implemented to support the AS bacteria that leads to the microalgae activated sludge (MAAS) process. The main advantage is combined removal of nutrients.

    The vision of the research is to implement the indigenous microalgae cultivation in activated sludge process to consume CO2 and recover the nutrients from wastewater. This study is performed to improve the understanding of the process such as: light utilisation, nutrient removal and recovery of the biomass from wastewater in closed photo-bioreactors. Photo-bioreactors are vessels where the cultivation is carried out in the presence of light. At first, the influence of the light spectrum on micro-algal cultivation is investigated for photosynthetic growth. This is followed by operational challenges of the microalgae cultivation during the AS process. The process is experimentally performed in the photo-bioreactors with different treatment time of the raw wastewater. The results showed that 2 - 6 days of treatment time can be used for reducing nutrients in wastewater if the process is optimised further. Also, nutrient ratio is analysed for the availability of the micro-algal growth. Furthermore, the biogas potential of MAAS showed a biogas yield of about 60-80% within 5 to 9 days.

    At last, the experimental verification of chemically precipitated wastewater showed limitation of phosphorous for micro-algal growth. Additionally, the optimal oxygen supply through light response is verified for photo-bioreactors. The outcome of this study shows that knowing the right conditions can lower the treatment time. By doing so, a stable nutrient removal and reduction of precipitation chemicals can be established as well as a better recovery of valuable nutrients as phosphorous and nitrogen.

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  • 29.
    Anbalagan, Anbarasan
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Jeanette Castro, Cynthia
    University of Massachusetts Amherst, US.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindberg, Carl-Fredrik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. ABB AB Corporate Research, Sweden.
    Nehrenheim, Emma
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Northvolt AB, Sweden.
    Butler, Caitlyn
    University of Massachusetts Amherst, US.
    Influence of environmental stress on the microalgal-bacterial process during nitrogen removalManuscript (preprint) (Other academic)
  • 30.
    Anbalagan, Anbarasan
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindberg, Carl-Fredrik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Nehrenheim, Emma
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Influence of light intensity and phosphorous on microalgae activated sludge in phosphate precipitated conditionManuscript (preprint) (Other academic)
  • 31.
    Anbalagan, Anbarasan
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindberg, Carl Fredrik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. ABB AB, Corporate Research, Västerås, Sweden.
    Nehrenheim, Emma
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Influence of hydraulic retention time on indigenous microalgae and activated sludge process2016In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 91, p. 277-284Article in journal (Refereed)
    Abstract [en]

    Integration of the microalgae and activated sludge (MAAS) process in municipal wastewater treatment and biogas production from recovered MAAS was investigated by studying the hydraulic retention time (HRT) of semi-continuous photo-bioreactors. An average total nitrogen (TN) removal efficiency (RE) of maximum 81.5 ± 5.1 and 64.6 ± 16.2% was achieved at 6 and 4 days HRT. RE of total phosphorous (TP) increased slightly at 6 days (80 ± 12%) HRT and stabilized at 4 days (56 ± 5%) and 2 days (55.5 ± 5.5%) HRT due to the fluctuations in COD and N/P mass ratio of the periodic wastewater. COD and organic carbon were removed efficiently and a rapidly settleable MAAS with a sludge volume index (SVI_10) of less than 117 mL g-1 was observed at all HRTs. The anaerobic digestion of the untreated MAAS showed a higher biogas yield of 349 ± 10 mL g VS-1 with 2 days HRT due to a low solids retention time (SRT). Thermal pretreatment of the MAAS (120 °C, 120 min) did not show any improvement with biogas production at 6 days (269 ± 3 (untreated) and 266 ± 16 (treated) mL gVS-1), 4 days (258 ± 11(untreated) and 263 ± 10 (treated) mL gVS-1) and 2 days (308 ± 19 mL (treated) gVS-1) HRT. Hence, the biogas potential tests showed that the untreated MAAS was a feasible substrate for biogas production. Results from this proof of concept support the application of MAAS in wastewater treatment for Swedish conditions to reduce aeration, precipitation chemicals and CO2 emissions. 

  • 32.
    Anbalagan, Anbarasan
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. University of Valladolid, Dr. Mergelina s/n, Valladolid, Spain.
    Toledo-Cervantes, A.
    University of Valladolid, Dr. Mergelina s/n, Valladolid, Spain.
    Posadas, E.
    University of Valladolid, Dr. Mergelina s/n, Valladolid, Spain.
    Rojo, E. M.
    University of Valladolid, Dr. Mergelina s/n, Valladolid, Spain.
    Lebrero, R.
    University of Valladolid, Dr. Mergelina s/n, Valladolid, Spain.
    González-Sánchez, A.
    University of Valladolid, Dr. Mergelina s/n, Valladolid, Spain.
    Nehrenheim, Emma
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Muñoz, R.
    University of Valladolid, Dr. Mergelina s/n, Valladolid, Spain.
    Continuous photosynthetic abatement of CO2 and volatile organic compounds from exhaust gas coupled to wastewater treatment: Evaluation of tubular algal-bacterial photobioreactor2017In: Journal of CO2 Utilization, ISSN 2212-9820, E-ISSN 2212-9839, Vol. 21, p. 353-359Article in journal (Refereed)
    Abstract [en]

    The continuous abatement of CO2 and toluene from the exhaust gas by an indigenous microalgal-bacterial consortium was investigated in a pilot tubular photobioreactor interconnected to an absorption column using diluted centrate in seawater as a free nutrient source. The removal efficiency of CO2 and toluene was maximised in the vertical absorption column by identifying an optimum liquid to gas (L/G) ratio of 15. The photobioreactor supported steady-state nitrogen and phosphorus removals of 91 ± 2% and 95 ± 4% using 15% diluted centrate at 14 and 7 d of hydraulic retention time (HRT), respectively. A decrease in the removal efficiencies of nitrogen (36 ± 5%) and phosphorus (58 ± 10%) was recorded when using 30% diluted centrate at 7 d of HRT. The volumetric biomass productivities obtained at an HRT of 7 d accounted for 42 ± 11 and 80 ± 3 mg TSS L-1 d-1 using 15 and 30% centrate, respectively. Stable CO2 (76 ± 7%) and toluene removals (89 ± 5%) were achieved at an L/G ratio of 15 regardless of the HRT or centrate dilution. Hence, this study demonstrated the potential of algal-bacterial systems for the continuous removal of CO2 and volatile organic compounds from exhaust gas coupled with the simultaneous treatment of centrate. 

  • 33.
    Andersson, Anna
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Uncharted Waters: Non-target analysis of disinfection by-products in drinking water2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Disinfection by-products (DBPs) are potentially toxic compounds formed when drinking water is treated with disinfectants, such as chlorine or chloramine. A large proportion of the exposure to DBPs is still unknown and the health risks observed through epidemiological studies cannot be explained by DBPs known today. In this thesis, a part of the unknown DBP fraction is investigated, covering a wide range of non-volatile, chlorine/bromine-containing DBPs. The goals were to investigate how the compositions of these DBPs differ between water treatment plants, how their occurrence changes in the distribution system until reaching consumers and how new treatment techniques can reduce their formation and toxicity. To analyze unknown DBPs, a non-targeted approach adopting ultra-high-resolution mass spectrometry, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), was used, where the mass of molecules is measured with such accuracy that the elemental composition of individual DBPs can be calculated. A panel of bioassays was used to assess the combined toxic effects from these DBP mixtures. 

    The results show that the formation of these DBPs to a large extent was specific to each water treatment plant and that local conditions influenced DBP formation, based on e.g., the abundance of organic material with certain chemical structures, bromide and disinfection procedure and agent (chlorine or chloramine). The DBPs were detected in both chlorinated and chloraminated water and in all tap water samples, demonstrating that they are part of human exposure. The number of DBP formulae decreased and the DBP composition changed between drinking water treatment and consumer taps, suggesting that DBP exposure to consumers is not necessarily resembling measurements at the treatment plants. Evaluation of new treatment techniques showed that suspended ion exchange and ozonation have potential to decrease the formation and toxic effects of DBPs and that the removal of organic matter can influence qualitative aspects of DBP formation, such as the proportions of chlorine-containing (less toxic) versus bromine-containing (more toxic) DBPs. Through increased knowledge about the role and relevance of non-volatile DBPs, this work can contribute to future monitoring and actions to reduce the health risks associated with DBPs in chlorinated or chloraminated drinking water. 

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  • 34.
    Andersson, Anna
    et al.
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Lavonen, Elin
    Norrvatten, Sweden; Stockholm Vatten and Avfall, Sweden.
    Harir, Mourad
    Helmholtz Ctr Munich, Germany; Tech Univ Munich, Germany.
    Gonsior, Michael
    Univ Maryland, MD 20688 USA.
    Hertkorn, Norbert
    Helmholtz Ctr Munich, Germany.
    Schmitt-Kopplin, Philippe
    Helmholtz Ctr Munich, Germany; Tech Univ Munich, Germany.
    Kylin, Henrik
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences. North West Univ, South Africa.
    Bastviken, David
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Selective removal of natural organic matter during drinking water production changes the composition of disinfection by-products2020In: Environmental Science: Water Research & Technology, ISSN 2053-1400, E-ISSN 2053-1419, Vol. 6, no 3, p. 779-794Article in journal (Refereed)
    Abstract [en]

    Disinfection by-products (DBPs) are potentially toxic compounds formed upon chemical disinfection of drinking water. Controlling the levels and characteristics of dissolved organic matter (DOM) as precursor material for DBPs is a major target to reduce DBP formation. A pilot-scale treatment including suspended ion exchange (SIX (R)), a ceramic microfilter (CeraMac (R)) with in-line coagulation and optional pre-ozonation followed by granular activated carbon (GAC) filtration was compared with a conventional full-scale treatment based on DOM removal and DBP formation using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), rapid fractionation, liquid chromatography organic carbon detection (LC-OCD), adsorbable organic halogens (AOX) and trihalomethane (THM) analysis. The new treatment combination showed different selectivity for DOM removal, compared to the conventional, leading to changes in composition of the DBPs formed. SIX (R) and GAC had the largest impacts on reducing AOX and THM formation potentials but the high adsorptive capacity of GAC affected the diversity of detected DBPs most. Chlorination and chloramination of pilot treated water with doses normally used in Sweden produced low levels of AOX compared to the full-scale treatment, but FT-ICR MS revealed an abundance of brominated DBP species in contrast with the conventional treatment, which were dominated by chlorinated DBPs. This finding was largely linked to the high DOM removal by the pilot treatment, causing an increased Br-/C ratio and a higher formation of HOBr. Potential increases in Br-DBPs are important to consider in minimizing health risks associated with DBPs, because of the supposed higher toxicity of Br-DBPs compared to Cl-DBPs.

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  • 35.
    Andersson, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Optimering av driftstemperatur vid mesofil rötning av slam: - funktionskontroll vid Uppsalas reningsverk2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Energy efficient processes and the use of fossil free fuels play an important role in order to reduce the impact of climate change. Anaerobic digestion is a common way for stabilizing sewage sludge at wastewater treatment plants (WWTP). One of the benefits with anaerobic digestion is that it also produces biogas, a fossil free fuel with low greenhouse gas emissions. An operational temperature within the mesophilic range has proven to give a stable process with an unfluctuating production of gas. The mesophilic temperature range between 25-40°C but most processes are operated between 35-40°C. This study investigates the opportunity to lower the temperature within the mesophilic range in order to reduce energy consumption. It is important to maintain the production of biogas with a lower temperature. Therefore, the reduction in VS-content (VS-volatile solids), methane yield and time for degradation was determined by a BMP-experiment (BMP-Biochemical Methane Potential) in three different temperatures (32, 34.5 and 37.5°C). In order to quantify the reduction in heat consumption with lower operational temperatures the change in heat balance for a full-scale WWTP in Uppsala was calculated. A major part of the operational cost is dewatering of sludge and it is therefore important that it does not deteriorate with a lower temperature. The effect on the dewaterability at different temperatures was examined by a filterability test measuring CST (capillary suction time). The results from the study showed no significant difference in methane yield between 37.5°C and 34.5°C. The methane yield at 32°C was 11 % lower compared to 37.5°C but the degradation kinetic was not affected by a temperature change. The reduction in heat consumption was 14 % when the temperature was reduced to 34.5°C and 27 % when it was reduced to 32°C. The filterability test did not show a deterioration with lower temperatures. The study showed that it is possible to reduce the operational temperature for anaerobic digestion at the WWTP in Uppsala in order to reduce the energy consumption. To confirm these results a continuously experiment should be done, but this study shows that it is possible to get a successful degradation in a lower mesophilic temperature. This leads the way for further investigations within the mesophilic range and could lead to optimizing anaerobic digestion and the opportunity to get an energy efficient production of biogas.

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  • 36.
    Andersson, Linn
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Evaluation of biosand filter as a water treatment method in Ghana: An experimental study under local conditions in Ghana2017Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The availability to clean drinking water is something a lot of people take for granted today. Daily, there are about 1.8 billion people around the world that drinks water from a contaminated water source. Unfortunately, the deficiency is a fact, and about 361 000 children under the age of five die each year because of diarrheal disease (WHO, 2016a). 

    Earlier studies show that a biosand filter is an easy and efficient water purification method that cleans the water both physically, biologically and chemically. A biosand filter is often built using local material and is filled with sand, which makes the construction cheap and easy to repair is needed. Earlier studies have shown that this purification method can reduce waterborne disease by 99,9% with the help of a biofilm layer which develop in the top layer of the sand if the conditions are meet (CAWST, 2009).

    The purpose with this study was to build and evaluate a biosand filter as a water treatment method in Ghana. In total, three biosand filters was built with local material, each with different sand heights. The evaluation was done by studying the waters physical, biological and chemical properties before and after the filtration, which then was compared to the water quality standards from the World Health Organization (WHO) and Sweden. The results show that none of the three filters could produce water which met the standards for drinking water, which might be caused by the high flow of water through the filter which prevented the biofilm to grow. With the help from the results in Ghana, a new design of a water filter has been made to reduce the flow of water through the filter. Which gave a new biosand filter design with a diameter of 42 cm that, sand height of 80 cm and gravel height of 15 cm.  

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  • 37.
    Andersson, Sofia Lovisa
    IVL Swedish Environmental Research Institute.
    Kväveåtervinning genom stripping och kristallisation2021Report (Other academic)
    Abstract [sv]

    Denna rapport sammanställer erfarenheter och resultat från pilotskaleförsök med stripping och kristallisation för kväveåtervinning från avloppsvatten. Projektet har varit ett samarbete mellan EkoBalans och IVL Svenska Miljöinstitutet, där EkoBalans anläggning eco:N testats under sommaren 2020 på IVLs test- och demonstrationsanläggning Hammarby Sjöstadsverk.

    Försöken har visat att det i anläggningen är möjligt att behandla ett rejektvatten från avvattning av rötat slam med ammoniumhalt från 500 till 2000 mg NH4-N/L med en ammoniumreduktion överstigande 95 % över själva strippern.

    Pilotförsöken har också visat att kristalliserad ammoniumsulfat kunde utvinnas, även om begränsningar i tillgänglighet till försöksanläggningen och substrat som gjorde att kontinuerlig drift inte var möjlig.

    Inom projektet har även många praktiska erfarenheter genererats vilket bidragit till fortsatt utveckling av anläggningen.

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  • 38.
    Andersson, Sofia Lovisa
    et al.
    Stockholm Vatten och Avfall.
    Andersson, Sofia
    Sweco.
    Baresel, Christian
    IVL Swedish Environmental Research Institute.
    MBR-tekniken  − utmaningar och möjligheter för svenska avloppsreningsverk: Praktiska erfarenheter och framtidsutsikter baserat på nio år avpilotverksamhetoch en fullskaleimplementering2023Report (Other academic)
    Abstract [en]

    During 2013–2022, the membrane bioreactor technology (MBR) has been evaluated through pilot tests at the Hammarby Sjöstadsverk research facility, in preparation for full-scale implementation at the Henriksdal wastewater treatment plant. This report summarizes specific experiences, challenges, and opportunities identified. The pilot consists of pre- and post-denitrification with the addition of an external carbon source for nitrogen removal. Phosphorus is removed through pre- and simultaneous precipitation at three dosing points. The pilot has generally achieved stable treatment efficiency, even under high load conditions, with effluent concentrations far below the discharge requirements. This even with less consumption of chemicals compared to design values. The report includes results from various control strategies and a comparison of  different external carbon sources. The membrane operation was generally stable, with permeability ranging from 600 to 200 lmh/bar. Optimization of resource consumption has been a focus in the pilot project since 2018. Attempts to reduce membrane fouling and the amount of chemicals used for membrane cleaning have been conducted, showing, for example, a reduction of membrane cleaning chemical requirements to 30–40% of the design. This finding has partially been confirmed in the full-scale line. Tests with reduced sludge  recirculation to decrease energy consumption indicated no negative effects on membrane performance. Tests with a flux enhancer showed no apparent positive or negative changes in membrane permeability. However, tests with an antifoaming agent were effective in reducing and controlling foaming. An assessment of micropollutants such as pharmaceutical residues, microplastics and PFAS, showed comparable levels between the MBR pilot and the conventional activated sludge process at Henriksdal WWTP. Emissions of chlorinated compounds were measured during several recovery cleanings with sodium hypochlorite, indicating potential harm throughout the cleaning process from an exposure perspective. Measurements of greenhouse gas emissions showed varied emissions between different measurements. In addition to these and other results and aspects, experiences from other MBR plants in Sweden and internationally are also presented.The MBR pilot was also used for several other activities outlined in the report, including: ● Testing and comparing different carbon sources for post-denitrification, including sodium acetate, Brenntaplus, methanol, acetic acid, glycerol, ethanol, and internally produced VFA (volatile fatty acids). ● Biological phosphorus removal, although the process was not specifically designed for this purpose. This resulted in significantly lower consumption of precipitation chemicals than expected. ● Tests with advanced treatment techniques such as ozonation, activated carbon, and others for the removal of micropollutants. Experiences from other Swedish and international MBR plants are also described. ● Use of the MBR pilot as part of a direct potable reuse (DPR) system, which involves treating the purified wastewater for direct use as drinking water. Finally, the report discusses various aspects including decommissioning and management of spent membranes, general operational experiences, pilot to full-scale feedback, and future potential and challenges for MBR technology.

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  • 39. Andersson, Sofia Lovisa
    et al.
    Andersson, Sofia
    Baresel, Christian
    IVL Swedish Environmental Research Institute.
    Eriksson, Mikael
    Fujikawa, Mayumi Narongin
    IVL Swedish Environmental Research Institute.
    Carranza Muno, Andrea
    IVL Swedish Environmental Research Institute.
    Yang, Jing-Jing
    IVL Swedish Environmental Research Institute.
    Bornold, Niclas
    IVL Swedish Environmental Research Institute.
    Karlsson, Jesper
    IVL Swedish Environmental Research Institute.
    Långtidsförsök med membranbioreaktor för förbättrad avloppsvattenrening i kombination med kompakt slambehandling2023Report (Other academic)
    Abstract [en]

    Henriksdal wastewater treatment plant (WWTP) in Stockholm is currently being extended and rebuilt for increased capacity (from 0.8 to 1.6 million PE) and enhanced treatment efficiency (6 mg TN/L, 0.20 mg TP/L, 5 mg BOD7/L).

    The reconstruction includes retrofitting of the existing conventional activated sludge (CAS) tanks with a new membrane bioreactor (MBR) process containing 1.6 million m2 of membrane area. It also includes extended pretreatment and a new treatment step for thickening of primary sludge. Digestion of thick sludge (~6 % TS) will be done at thermophilic conditions, unlike today’s mesophilic operation, with high organic load and relatively short retention time.

    To increase the knowledge of MBRs in Nordic conditions, Stockholm Vatten och Avfall (SVOA) and IVL Swedish Environmental Research Institute have conducted long-term MBR studies in pilot scale at the R&D-facility Hammarby Sjöstadsverk, located on the premises of the Henriksdal WWTP. The MBR-pilot was taken into operation in 2013 and was reconstructed to its current configuration in 2016. In 2017 the MBR pilot was supplemented with a sludge treatment line to study different aspects of sludge digestion. 

    During 2021, the MBR-pilot was operated at a fixed inflow of 4.1 m3/h, which is 37 % higher than the design average flow, with externally provided glycerol as well as internally produced VFA as carbon source for post-denitrification. Aluminum (PAX) was used instead of Ferric (PIX) as complement to Ferrous (FeSO4) for phosphorous precipitation. This was done to test the operational strategy for the first MBR line in Henriksdal WWTP. The average effluent concentration of nitrogen and phosphorus was 3.9 mg TN/L and 0.07 mg TP/L, respectively, which means that the effluent requirements were met also this year. To achieve this, 8.6 g Fe2+/m3 and 0.9 g Al3+/m3 was required.

    During flux enhancer trials a total of 17.8 g iron (Fe2+ + Fe3+)/m3 was added. The glycerol dose was equivalent to 17.3 g COD/m3 and for internally produced VFA the dose equivalent was 15.5 g COD/m3. The slightly higher consumption of phosphorus precipitation chemicals compared to 2020, 1.29 mole metal per mole of phosphorus removed, was mainly due to a lower enhanced biological phospho¬rus removal (EBPR) activity in 2021. In 2021 the phosphorous release rates were low during the spring and showed < 1 g PO4-P/kg VSS,h in June but recovered in the summer with 5.5 g PO4-P/kg VSS,h in July after the defoaming agent dosing was stopped.

    The iron and aluminum content in the activated sludge was 6.2 and 0.7 %, respectively. Average total sludge age during 2021 was 17.2 days and average aerated sludge age was 7 days. Nitrification was always complete with ammonia concentrations below 2 mg/L except week 25. Test with use of internally produced VFA as carbon source showed that the specific COD consumption was almost the same as for glycerol when comparing the yearly average from 2021 and 2020. Effluent nitrate and total nitrogen removal was similar during the trial with VFA as the rest of the year, when glycerol was used.

     Like previous years, the membranes in membrane tank 1 (MT1) was cleaned with oxalic acid and the membranes in MT2 with citric acid. Both membranes were also cleaned with sodium hypochlorite. The membranes were operated with an average net flux around 21 to 25 L/(m2·h) but starting from week 25, the flux was increased to 30 L/(m2·h) which is the design net max flux of the full scale MBR in Henriksdal and was tested in the pilot for 25 weeks.

    The net TMP varied between 49 and 218 mbar for MT1 and between 51 and 146 mbar for MT2. TMP was reduced after each recovery cleaning (RC) with hypochlorite, but the effect did not last long. The permeability was generally above 200 L/(m2·h·bar) throughout 2021-2022 for both membranes. Recovery cleanings were done twice with hypochlorite and once with acids during 2021. During 2022 a final RC, first with hypochlorite then with acids was carried out.

    The first RC for MT1 resulted in a clear increase in permeability after cleaning. For MT2 the major increase in permeability was the result of a citric acid MC (one week after the hypochlorite RC). The RCs at the end of 2021 and in March 2022 had clear but smaller positive impact on permeability. Prior to the first RCs, permeability was higher for MT1 (cleaned with oxalic acid) compared to MT2 (cleaned with citric acid). After the first RCs, both membranes had similar permeability. As a result of the tough operational strategy from week 25 2021, permeability decreased quite quickly after RCs. MT2 reached a stable level around 250-300 L/(m2·h·bar) while MT1 decreased even more, to as low as around 200 L/(m2·h·bar). 

    Emission of chlorinated compounds in the off-gas ventilation were measured during the final sodium hypochlorite recovery cleaning. The emission process was slower than expected and generally no clear sign of attenuation of emissions was observed during the 21 hours of sampling. Although composite samples of several hours during the night are not providing enough details, it was concluded that the emissions can be harmful during the entire RC process from an exposure perspective. Trichloramine peaked at 36 times the recommended limit, chlorine gas at 73 % of the short-term exposure limit (15 min exposure), and chloroform at 9 % of the occupational exposure limit (8-hour workday average).To follow up previous measurements of greenhouse gases nitrous oxide (N2O) and methane (CH4), a new campaign was performed during several months in 2021. Generally, emissions observed in 2021 were significantly higher than in previous campaigns in the pilot and especially high N2O-emissions from the membrane-tank could be identified.

    No clear reason could be identified but the increased incoming load with a maintained effluent quality and a “better” sampling setup may partly be an explanation.In collaboration with Kemira, tests with a flux enhancer product were performed in 2021. However, no obvious positive or negative change in permeability due to dosing of flux enhancer was possible to identify based on continuously monitored process parameters and commonly observed variations in permeability and effect of membrane cleaning.  As the formation of foam is a common phenomenon in MBR plants, tests with an antifoaming agent were done by dosing in batches and continuously to the biological treatment during the period of heavy foaming (March-June).

    Even if foaming was not avoided, a good reduction and control of foaming could be achieved. An optimal effect was achieved with continuous dosages of > 10 ppm. However, even though the product has shown to have a positive effect in the MBR-pilot, a permanent use in full-scale may not be economically feasible due to the high consumption.Test with a reduced RAS flow from the design value of 4×Qin to 2×Qin was done with the aim to reduce energy consumption for pumping. A reduced RAS flow would however imply an increased sludge concentration in the membrane tanks, which may have negative effects on the membrane performance with more clogging and consequently increased aeration for membrane scouring and need for more frequent membrane cleaning.

    However, no negative effects of the reduced RAS-flow could be seen on the membrane performance.    During 2021, tests with a transition from mesophilic to thermophilic anaerobic digestion, dewatering of digested sludge after mesophilic and thermophilic digestion, and thermophilic digestion at high organic loading rate (OLR) and low hydraulic retention time (HRT) were performed in the sludge pilot. Results show that the transition from mesophilic to thermophilic digestion can be done without any major problems if the load was reduced during the most critical temperatures and that stable operation was achieved after 10-12 days. Evaluating the dewatering of mesophilically and thermophilically digested sludge was more difficult and no clear differences could be observed. However, it was concluded that used methods for determining dewaterability or optimal polymer dose are not reliable.

    Trials with high organic loading rate at thermophilic digestion showed that the digester performance could be maintained up to an OLR of around 4 kg VS/m3, d and an HRT of 12 d. When the load is further increased and HRT decreased, the performance in terms of VS reduction and biogas-/methane production decreased although the reactor operation was still stable.   The overall resource consumption in the pilot showed that the consumption of glycerol was the same as for the future Henriksdal design, even though the nitrogen load in the pilot was 21 % higher and the average effluent total nitrogen concentration was 3.9 mg TN/L compared to the design of 6 mg TN/L.

    Also, the iron/metal consumption was 73 % of the future Henriksdal design, although the phosphorus load to the pilot was about 50 % higher compared to design values and effluent phosphate concentrations were below the target concentration. This is mainly explained by the EBPR activity in the pilot. Also, the consumption of cleaning chemicals was lower than the future Henriksdal design although the inflow to the pilot was 30 % higher than design.

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    pH2040 årsrapport 2021 2022
  • 40.
    Anlind, Nils
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Eriksson, Alexandra
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Gromova, Arina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Hong, Marcus
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Ljungström, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Markstedt, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Marknadsanalys av proteinstandarder för kvantitativ masspektrometri2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    QPrEST är en ny intern standard för absolut kvantifiering av proteiner utvecklat av företaget Atlas Antibodies AB. I en marknad där det redan finns etablerade standarder kan det vara svårt att konkurrera ut de nuvarande produkterna. Därför har denna rapport gjorts vilken består av en marknadsanalys av nuvarande standarder, statistisk undersökning av publicerade artiklar inom absolut kvantitativ proteomik samt en global kundundersökning med 35 svarande. Resultaten har legat till grund för förbättringsförslag till Atlas Antibodies AB för bättre marknadsföring och lansering av sin nya produkt, QPrEST. Slutsatsen från denna rapport är att Atlas Antibodies AB måste nischa in sin produkt till kvantifiering av ett målprotein då det är där standarden presterar bäst.

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  • 41.
    Annaduzzaman, Md.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Deshpande, Paritosh Chakor
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Ersoz, M.
    Lazarova, Z.
    Chitosan biopolymer: a treatment option for uranium(VI) removal from drinking waterManuscript (preprint) (Other academic)
  • 42.
    Annaduzzaman, Md.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Ersoz, M.
    Lazarova, Z.
    Characterization of a chitosan biopolymer and arsenate removal for drinking water treatment2014In: One Century of the Discovery of Arsenicosis in Latin America (1914-2014): As 2014 - Proceedings of the 5th International Congress on Arsenic in the Environment, CRC Press, 2014, p. 745-747Conference paper (Refereed)
    Abstract [en]

    Chitosan biopolymer with a deacetylation degree of 85%, was assessed for its capability to adsorb As(V) from drinking water by batch experiments. To characterize the chitosan biopolymer, chitosan was analyzed by FTIR and SEM. The results showed that chitosan is an effective and promising sorbent for As(V) from drinking water. From the batch tests, results showed a maximum adsorption of 355 μg/L of As(V) with 1.18 μg g-1 adsorption capacity at pH 6. The kinetic data, obtained at pH 6 could be fitted with pseudo-second order equation (adsorption capacity: 0.923 μg g-1) and the process was suitably described by a Freundlich (R2 = 0.9933) model than by a Langmuir model (R2 = 0.9741). The results above indicated that chitosan is a very favorable sorbent for As(V) removal from aqueous solution.

  • 43.
    Annaduzzaman, Md.
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Ersoz, M.
    Lazarova, Z.
    Evaluation and optimization of chitosan biopolymer as an adsorbent for arsenic(V) in drinking watert treatmentManuscript (preprint) (Other academic)
  • 44.
    Arab Goueini, Shahdokht
    University of Borås, Faculty of Textiles, Engineering and Business.
    Produktion av polyhydroxialkanoater (PHA) med Bacillus megaterium2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Plastic production and use of plastic are increasing every year throughout the world and this is one of the world's biggest problems. Plastic is a persistent substance, and its biodegradation process can take hundreds of years. This in turn leads to the accumulation of plastic causing harmful effects on the climate, the environment, and people. One of the alternatives that has great potential when it comes to dealing with this problem is to reduce the use of plastics and instead increase the production and use of bioplastics or biopolymers that are biodegradable.

    Bioplastics have a shorter biodegradation time than plastics and therefore bioplastics are a good alternative instead of using ordinary plastic. There are three different groups of bioplastics, namely those that are bio-based, those that are biodegradable and those that are both bio-based and biodegradable.

    One type of bioplastic that is biodegradable and bio-based is Polyhydroxyalkanoates (PHA) which are used in various industries as PHA is one of the biopolymers that shows the greatest potential to replace plastic in the future.

    Research is underway at the University of Borås with the goal of developing a new process for the production and recycling of PHAs. The process is based on the production of PHAs from volatile fatty acids produced from acidogenic fermentation. Acid fermentation is a modified process of anaerobic digestion; the latter is used nowadays to produce biogas from waste and can be the right process for recycling PHA-based waste and for producing a cheap substrate, namely volatile fatty acids for PHA's production. This project is about a part of the process, namely the production of PHAs with bacteria. The research group at the University of Borås has a bacterial strain that has not been yet investigated for the production of PHAs. Before this bacterium can be studied for the production of PHAs from volatile fatty acids the compositionoptimization of the cultivation medium for bacterial growth is needed.

    The purpose of this work is to investigate the effect of different glucose concentrations as a source of carbon and different amounts of ammonium sulphate in the growth of the bacterium Bacillus megaterium and the production of polyhydroxyalkanoates. A comparison between the defined medium under development in this project with nutrient broth, a complex medium normally used to grow bacteria, was also carried out in order to evaluate the suitability of the defined medium to support bacterial growth. During this work several different analytical techniques have been used such as pH measurement, High-Performance Liquid Chromatography (HPLC), Spectrometer (for optical density (OD) measurement), and Fourier-Transform Infrared Spectroscopy (FTIR) to evaluate bacterial growth and production of PHA as well as PHAs composition.

    The amount of ammonium sulphate affected glucose consumption rate, where concentrations of 3 g/L and 7 g/L were shown to lead to a faster glucose consumption compared to that at 5 g/L. Therefore, 3 g/L ammonium sulphate was chosen as it represents less chemical consumption while not affecting cell growth negatively. During bacterial cultivation in a medium containing 3 g/L ammonium sulphate, 10 g/L glucose, among other compounds, glucose was completely consumed after 72 hours of bacterial growth and the maximum PHA production was 13-14% based on cell dry weight. The cultivation medium developed in this project was shown to be suitable for bacterial growth since the use of nutrient broth, normally used for bacterial growth, led to slower glucose consumption.

    Initial glucose concentration (5, 10 and 20 g/L) did not affect glucose consumption rate and should be further studied to increase cell concentration and consequently the production of PHA. One of the most studied polymers in the PHA family is polyhydroxybutyrate (PHB). During this work, it was found, through the use of FTIR, that PHB was produced.

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    Produktion av polyhydroxialkanoater (PHA) med Bacillus megaterium
  • 45.
    Argatov, Ivan
    et al.
    Tech Univ Berlin, Inst Mech, D-10623 Berlin, Germany..
    Krcic, Nedim
    Magle Chemoswed, Agneslundsvagen 27, SE-21215 Malmö, Sweden..
    Kocherbitov, Vitaly
    Malmö University, Faculty of Health and Society (HS), Department of Biomedical Science (BMV). Malmö University, Biofilms Research Center for Biointerfaces.
    Sedimentation of a starch microsphere: What is usually missed and why?2023In: Heliyon, E-ISSN 2405-8440, Vol. 9, no 10, article id e20257Article in journal (Refereed)
    Abstract [en]

    Gravimetric sedimentation is known as a relatively simple method of determining density of spherical particles. When the method is applied to water-swollen starch microparticles of about submillimeter sizes, it becomes evident that a careful selection of the experimental setup parameters is needed for producing accurate testing results. The main reason for this is that the mean particle density is very close to the density of water, and therefore, a dynamic model accounting for the so-called Bassett history force should be employed for describing the unsteady accelerating particle settling. A main novelty of this study consists in deriving a priori estimates for the settling time and distance.

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  • 46. Arshadi, Mehrdad
    et al.
    Sellstedt, Anita
    Unit of Biomass Technology and Chemistry / BTK, Swedish University of Agricultural Sciences, Umea, Sweden.
    Production of energy from biomass2008In: Introduction to chemicals from biomass / [ed] James H. Clark with Fabien E.I. Deswarte, John Wiley & Sons, 2008, p. 143-178Chapter in book (Refereed)
  • 47.
    Arvidsson, Daniel
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Estimation of the possible waste reduction by the implementation of SODIS: A numerical-, experimental- and social study executed in Ghana2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lack of safe drinking water is one of the biggest humanitarian problems in the world today. Over one billion people in developing countries have no access to good quality drinking water, and subsequently, diarrhoea caused by unclean water leads to 1.8 million deaths of children under the age of five. That corresponds to 90 per cent of all deaths among children in that age group. However, by improving water and sanitation management, one tenth of all worldwide cases of disease can be prevented. In relation to this, the United Nations has launched the seventh millennium goal, which is to half the proportion of people lacking access to safe drinking water by year 2015 (compared with the proportion of year 2000). Therefore, it is important to both improve and develop water treatment techniques in order to achieve a sustainable development, especially in the third world.

     

    Kofi Ansah and Edumafa are two villages on the Ghanaian countryside. Here, as in the rest of Ghana, it is common to drink water from throwaway plastic containers. This is because the water quality is poor in the stationary water sources such as tanks and wells etc. The plastic containers contribute to a big waste problem and it´s therefore desirable to improve the water quality in stationary water sources in order to reduce the waste problem that now is occurring.

     

    Solar Disinfection, or SODIS, is a water treatment technique that is based on solar radiation. Water containers (usually PET bottles) are filled with water and then exposed to the sun for about six hours. The germicidal effect can be derived to thermal heating in combination with the sun’s ultraviolet radiation. The technique is suitable in the third world since the treatment procedure is both simple and inexpensive. The purpose of this study was to estimate the possible waste reduction regarding the small plastic containers by the implementation of SODIS as a water treatment technique, and evaluate if SODIS is an adequate way to improve the quality of water collected from stationary water distribution systems in Ghana.

     

    The study has shown that SODIS is an adequate method for producing low health risk water at a household level in Ghana. A solar exposure of six hours is enough to reach a safe bacterial content within the treated water. It is also clear that SODIS could reduce the present waste problem regarding the throwaway plastic containers by more than 1600 plastic bags per person and year, and that the Ghanaians attitude to start performing SODIS is positive.

     

    Further work should be aimed at implementing SODIS as a water treatment technique by teaching the Ghanaian people, especially in the rural areas, the importance of water and sanitation issues. The implementation of SODIS is a long term project that cannot be accomplished singlehandedly. It can be achieved by instructing certain people in the villages as to how the procedure is done. For this to be effective, these individuals should preferably be well educated and speak both English and the local language. These people can in turn educate and instruct the other villagers in how SODIS is executed and by doing so complete and secure a sustainable use of the technique.

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    Estimation of the possible waste reduction by the implementation of SODIS
  • 48.
    Arvidsson, Staffan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Berglund, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Ehrenborg, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Ghiassi Tari, Parisa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Ledent, Sofie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Nordstedt, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Nya dispenseringstekniker för feromoner: För ett hållbart jordbruk2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Projektets mål har varit att utveckla nya alternativa dispenseringstekniker för insektsferomoner som bekämpar skadeinsekter på fruktodlingar. Resultatet av projektet har gett tre teoretiskt möjliga förslag. Det första förslaget är en polymerbaserad feromondispensering som inte är baserad på någon nuvarande teknik. Förslaget är uppdelat i två koncept, antingen en polymer i gelform eller en gjuten polymer. Polymererna som ges i förslaget är biologiskt nedbrytbara och har egenskaper som inte finns i produkter på marknaden idag. Det andra förslaget grundar sig på vaxbaserad feromondispensering som är en nuvarande teknik. En vaxmassa blandas tillsammans med en specifik feromonlösing och appliceras direkt på ett bladverk eller i fällor. Genom att ha en definierad form på dispensrarna erhålls en bättre kontroll på utsöndring av feromon. Det tredje förslaget är en sprejbaserad feromondispensering även den grundas på nuvarande tekniker. Idén är att en sprejbehållare med tillhörande feromonlösning kan fjärrstyras genom att kopplas till ett kontrollsystem. Fördelen med tekniken är att en större kontroll över dispenseringen på fruktodlingsfältet kan uppnås utifrån information från en väderstation eller annan källa. Kontrollsystemet kan ställas in för att rätt mängd feromon skall släppas ut i olika väderförhållande.

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    Nya dispenseringstekniker för feromoner
  • 49.
    Ashiq, Muhammad Jamshaid
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    The occurrence of disinfection by-products in four Swedish drinking waterworks2022Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Disinfection by-products (DBPs) are unwanted, potentially toxic compounds formed when drinking water is disinfected with chemical disinfectants such as chlorine or chloramine. The levels of DBPs produced depends on parameters, such as levels of natural organic matter (NOM) and the nature and concentration of chemical disinfectant used. In this thesis, the effects of two different types of chemical disinfectants, chlorine and chloramine, are investigated in terms of levels of DBP production. The goal was to investigate if chlorine disinfection produces similar levels and types of DBPs as in case of chloramination.

    Within the thesis work was also tested a method based on a gas chromatograph coupled with halogen selective detector (GC-XSD) to determine the known DBPs in the drinking water.

    The results show that the formation of DBPs at chlorine or chloramine disinfection were similar. Still, chloramine is preferably used because it produces less legally regulated DBPs.

    The GC-XSD worked well for the determination of DBPs in drinking water. Since XSD is very selective and specific towards halogens and easy to operate, therefore this setup not only a potential tool for routine DBPs monitoring at drinking water facilities, but it could also be used for the determination of unknow halogenated compounds.

    Through increased knowledge in the formation of DBPs and their determination with GC-XSD can contribute to the development of better methods to quantify known and identify unknow halogenated organic compounds in treated drinking water and reduce public exposure to potentially toxic halogenated organic compounds.

  • 50.
    Ashraf, Imtiaz
    et al.
    School of Chemical Engineering, Northwest University, Xi’an 710069, China.
    Li, Rong
    School of Chemical Engineering, Northwest University, Xi’an 710069, China.
    Chen, Bin
    School of Chemical Engineering, Northwest University, Xi’an 710069, China.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Rizwan Aslam, Muhammad
    College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310027, China.
    Altaf, Adnan Raza
    College of Engineering, Huazhong Agricultural University, Wuhan 430070, China.
    Elbeltagi, Ahmed
    Agricultural Engineering Department, Faculty of Agriculture, Mansoura University, Mansoura 35516, Egypt.
    Nanoarchitectonics and Kinetics Insights into Fluoride Removal from Drinking Water Using Magnetic Tea Biochar2022In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 19, no 20, article id 13092Article in journal (Refereed)
    Abstract [en]

    Fluoride contamination in water is a key problem facing the world, leading to health problems such as dental and skeletal fluorosis. So, we used low-cost multifunctional tea biochar (TBC) and magnetic tea biochar (MTBC) prepared by facile one-step pyrolysis of waste tea leaves. The TBC and MTBC were characterized by XRD, SEM, FTIR, and VSM. Both TBC and MTBC contain high carbon contents of 63.45 and 63.75%, respectively. The surface area of MTBC (115.65 m2/g) was higher than TBC (81.64 m2/g). The modified biochar MTBC was further used to remediate the fluoride-contaminated water. The fluoride adsorption testing was conducted using the batch method at 298, 308, and 318 K. The maximum fluoride removal efficiency (E%) using MTBC was 98% when the adsorbent dosage was 0.5 g/L and the fluoride concentration was 50 mg/L. The experiment data for fluoride adsorption on MTBC best fit the pseudo 2nd order, rather than the pseudo 1st order. In addition, the intraparticle diffusion model predicts the boundary diffusion. Langmuir, Freundlich, Temkin, and Dubnin–Radushkevich isotherm models were fitted to explain the fluoride adsorption on MTBC. The Langmuir adsorption capacity of MTBC = 18.78 mg/g was recorded at 298 K and decreased as the temperature increased. The MTBC biochar was reused in ten cycles, and the E% was still 85%. The obtained biochar with a large pore size and high removal efficiency may be an effective and low-cost adsorbent for treating fluoride-containing water.

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