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  • 1.
    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.

  • 2.
    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)
  • 3.
    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.

  • 4.
    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)
  • 5. Asim, Muhammad
    et al.
    Kumar, N. T. Uday
    Martin, Andrew R.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Feasibility analysis of solar combi-system for simultaneous production of pure drinking water via membrane distillation and domestic hot water for single-family villa: pilot plant setup in Dubai2016In: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986, Vol. 57, no 46, p. 21674-21684Article in journal (Refereed)
    Abstract [en]

    This paper presents the feasibility study of installation of a solar-driven integrated MD desalination system for simultaneous production of pure drinking water and solar domestic hot water in United Arab Emirates (UAE) for a single-family villa comprising of 4-5 persons. In order to satisfy the current and future demand of water for domestic purposes, the desalination of seawater is considered to be one of the most effective and strategic technique in UAE. The stress on the underground water aquifers, rapid industrial growth, and increase in urban population in UAE results in the tremendous increase in fresh water demand during the past few decades. Since the local municipalities also provide the desalinated fresh water to the people but they mostly rely on bottled water for drinking purpose. In this paper, the pilot setup plant is designed, commissioned, and installed on site in UAE using air gap membrane distillation desalination process to fulfill the demand of 15-25 L/d of pure drinking water and 250 L/d of domestic hot water for a single-family villa. Experimental analyses have been performed on this setup during summer on flat plate solar collectors having different aperture areas (Experiments have been performed for aperture area of 11.9 m(2) in this research study for feasibility purpose). The average hot-side temperature ranges from 50 to 70 degrees C and average cold-side temperature of 35 degrees C.

  • 6.
    Axelsson, Karolin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. KTH, School of Biotechnology (BIO).
    Konstanzer, Vera
    KTH.
    Rajarao, Gunaratna Kuttuva
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Terenius, Olle
    Seriot, Lisa
    KTH, School of Biotechnology (BIO).
    Nordenhem, Henrik
    Nordlander, Goran
    Borg-Karlson, Anna-Karin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. Tartu University, Estonia.
    Antifeedants Produced by Bacteria Associated with the Gut of the Pine Weevil Hylobius abietis2017In: Microbial Ecology, ISSN 0095-3628, E-ISSN 1432-184X, Vol. 74, no 1, p. 177-184Article in journal (Refereed)
    Abstract [en]

    The pine weevil, Hylobius abietis, is a severe forest pest insect as it feeds on newly planted conifer seedlings. To identify and develop an antifeedant could be one step towards the protection of seedlings from feeding damage by the pine weevil. With the aim to trace the origin of the antifeedants previously found in feces of the pine weevil, we investigated the culturable bacteria associated with the gut and identified the volatiles they produced. Bacterial isolates were identified by 16S ribosomal RNA gene analysis. The volatile emissions of selected bacteria, cultivated on NB media or on the grated phloem of Scots pine twigs dispersed in water, were collected and analyzed by solid-phase microextraction gas chromatography-mass spectrometry. The bacterial isolates released a variety of compounds, among others 2-methoxyphenol, 2-phenylethanol, 3-methyl-1-butanol, 1-octen-3-ol, 3-octanone, dimethyl disulfide, and dimethyl trisulfide. A strong antifeedant effect was observed by 2-phenylethanol, which could thus be a good candidate for use to protect planted conifer seedlings against feeding damage caused by H. abietis.

  • 7.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Hossain, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Ahmed, K. M.
    Hasan, M. A.
    Von Brömssen, M.
    Groundwater arsenic pollution: A conceptual framework for sustainable mitigation strategy2014In: 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. 881-885Conference paper (Refereed)
    Abstract [en]

    Tubewells installed by local drillers, provide access of drinking water in rural Bangladesh. Significant proportion of these wells contains arsenic (As) above the WHO guideline and the Bangladesh Drinking Water Standard. Various attempts for mitigation at household and community scale have resulted in limited success, but through the local driller's initiatives, the tubewells are the source of priority drinking water supply. We have developed a concept of Sustainable Arsenic Mitigation (SASMIT) to identify and target the safe aquifers through detailed hydrogeological studies for scientific validation of the water quality with respect to the color of the shallow sediments as perceived by local drillers. Together with water quality monitoring, we have also targeted the Intermediate Depth Aquifers (IDA) for providing As-safe and low manganese (Mn) water. SASMIT intervention logic also considered the relevant socio-economic scenario, such as household distribution, poverty issues and available safe water access for prioritizing safe well installation.

  • 8.
    Bhattacharya, Prosun
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. International Groundwater Arsenic Research Group.
    von Brömssen, Mattias
    Department of Soil and Water Environment Ramböll Sweden AB.
    Targeting Arsenic-Safe Aquifers in Regions with High Arsenic Groundwater and its Worldwide Implications (TASA)2015Report (Other academic)
  • 9.
    Biswas, Ashis
    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, Land and Water Resources Engineering.
    Mukherjee, Abhijit
    Nath, Bibhash
    Alexanderson, Helena
    Kundu, Amit K.
    Chatterjee, Debashis
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Shallow hydrostratigraphy in an arsenic affected region of Bengal Basin: Implication for targeting safe aquifers for drinking water supply2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 485, p. 12-22Article in journal (Refereed)
    Abstract [en]

    To delineate arsenic (As) safe aquifer(s) within shallow depth, the present study has investigated the shallow hydrostratigraphic framework over an area of 100 km(2) at Chakdaha Block of Nadia District, West Bengal. Drilling of 29 boreholes and subsequent hydrostratigraphic modeling has identified three types of aquifer within 50 m below ground level (bgl). Aquifer-1 represents a thick paleochannel sequence, deposited parallel to the River Hooghly and Ichamati. Aquifer-2 is formed locally within the overbank deposits in the central floodplain area and its vertical extension is strictly limited to 25 m bgl. Aquifer-3 is distributed underneath the overbank deposits and represents an interfluvial aquifer of the area. Aquifer-3 is of Pleistocene age (similar to 70 ka), while aquifer-1 and 2 represent the Holocene deposits (age <951 ka), indicating that there was a major hiatus in the sediment deposition after depositing the aquifer-3. Over the area, aquifer-3 is markedly separated from the overlying Holocene deposits by successive upward sequences of brown and olive to pale blue impervious clay layers. The groundwater quality is very much similar in aquifer-1 and 2, where the concentration of As and Fe very commonly exceeds 10 mu g/L and 5 mg/L, respectively. Based on similar sediment color, these two aquifers have jointly been designated as the gray sand aquifer (GSA), which constitutes 40% (1.84 x 10(9) m(3)) of the total drilled volume (4.65 x 10(9) m(3)). In aquifer-3, the concentration of As and Fe is very low, mostly <2 mu g/L and 1 mg/L, respectively. This aquifer has been designated as the brown sand aquifer (BSA) according to color of the aquifer materials and represents 10% (4.8 x 10(8) m(3)) of the total drilled volume. This study further documents that though the concentration of As is very low at BSA, the concentration of Mn often exceeds the drinking water guidelines.

  • 10.
    Biswas, Ashis
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Neidhardt, Harald
    Halder, Dipti
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Kundu, Amit K.
    Chatterjee, Debashis
    Berner, Zsolt
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Role of competing ions in the mobilization of arsenic in groundwater of Bengal Basin: Insight from surface complexation modeling2014In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 55, p. 30-39Article in journal (Refereed)
    Abstract [en]

    This study assesses the role of competing ions in the mobilization of arsenic (As) by surface complexation modeling of the temporal variability of As in groundwater. The potential use of two different surface complexation models (SCMs), developed for ferrihydrite and goethite, has been explored to account for the temporal variation of As(III) and As(V) concentration, monitored in shallow groundwater of Bengal Basin over a period of 20 months. The SCM for ferrihydrite appears as the better predictor of the observed variation in both As(III) and As(V) concentrations in the study sites. It is estimated that among the competing ions, PO43- is the major competitor of As(III) and As(V) adsorption onto Fe oxyhydroxide, and the competition ability decreases in the order PO43- >> Fe(II) > H4SiO4 = HCO- (3.) It is further revealed that a small change in pH can also have a significant effect on the mobility of As(III) and As(V) in the aquifers. A decrease in pH increases the concentration of As(III), whereas it decreases the As(V) concentration and vice versa. The present study suggests that the reductive dissolution of Fe oxyhydroxide alone cannot explain the observed high As concentration in groundwater of the Bengal Basin. This study supports the view that the reductive dissolution of Fe oxyhydroxide followed by competitive sorption reactions with the aquifer sediment is the processes responsible for As enrichment in groundwater.

  • 11.
    Bodlund, Ida
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Coagulant Protein from plant materials: Potential Water Treatment Agent2013Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Access to fresh water is a human right, yet more than 780 million people, especially in rural areas, rely on unimproved sources and the need for finding ways of treating water is crucial. Although the use of natural coagulant protein in drinking water treatment has been discussed for a long time, the method is still not in practice, probably due to availability of material and limited knowledge. In this study, about hundred different crude extracts made from plant materials found in Southern India were screened for coagulation activity. Extracts of three Brassica species (Mustard, Cabbage and Cauliflower) were showing activity comparable to that of Moringa oleifera and were further investigated. Their protein content and profile were compared against each other and with coagulant protein from Moringa. Mustard (large) and Moringa seed proteins were also studied for their effect against clinically isolated bacterial strains. The protein profiles of Brassica extract showed predominant bands around 9kDa and 6.5kDa by SDS-PAGE. The peptide sequence analysis of Mustard large identified the 6.5kDa protein as Moringa coagulant protein (MO2.1) and the 9kDa protein band as seed storage protein napin3. Of thirteen clinical strains analysed, Moringa and Mustard large were proven effective in either aggregation activity or growth kinetic method or both in all thirteen and nine strains respectively. To my knowledge this is the first report on the presence of coagulant protein in Brassica seeds. Owing to the promising results Brassica species could possibly be used as a substitute to Moringa coagulating agent and chemicals in drinking water treatment. 

  • 12. Borghei, Seyed Mahmood
    et al.
    Nekooie, Mohammad Ali
    Sadeghian, Hadi
    Ghazizadeh, Mohammad Reza Jalili
    Parvaneh, Ali
    Yang, James
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Hydraulic Engineering.
    Javaheri, Amir
    Kabiri-Samani, Abdorreza
    Discussion: Triangular labyrinth side weirs with one and two cycles2016In: Proceedings of the Institution of Civil Engineers: Water Management, ISSN 1741-7589, E-ISSN 1751-7729, Vol. 169, no 3, p. 111-114Article in journal (Other academic)
  • 13. Brenner, A.
    et al.
    Persson, K. M.
    Russell, L.
    Rosborg, Ingegerd
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Kozisek, F.
    Technical and mineral level effects of water treatment2015In: Drinking Water Minerals and Mineral Balance: Importance, Health Significance, Safety Precautions, Springer, 2015, p. 103-117Chapter in book (Other academic)
    Abstract [en]

    Reverse Osmosis is used for desalination of especially sea water in areas suffering from water shortage, and there are thousands and thousands of desalination plants around the world and more to come. The produced high–purity water tends to be corrosive, and lacks minerals, causing decreased daily intake and loss of minerals from the body. Thus, such water needs re–mineralization. Water with toxic substances is harmful, and is also often treated with RO. There are indexes to be used as guides to choose re–mineralization method after RO. However, mineral balance is not reached by remineralization, as only concentrations of calcium and bicarbonate, and in some cases magnesium is increased. Treatment with dissolution of dolomitic–calcitic limestone or other limestone with low levels of toxic elements is preferable. Hard water, on the other hand, may cause scaling, and is often softened, making the concentrations of calcium and magnesium low or extremely low. General advices on choice of treatment method to preserve or improve the mineral content and mineral balance of a water is presented in the chapter.

  • 14.
    Cameli, Fabio
    KTH, School of Chemical Science and Engineering (CHE).
    Microbial Fuel Cell for Waste Water Treatment2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Microbial Fuel Cell is a novel technology that can be used for a waste water treatment in order to simultaneously remove carbonaceous matter and nitrogen while producing electrical power.

    Even if it is not an established technology so far, MFC could be a cost effective option for waste water treatment and the major challenge of this process will be the device scale-up. Exoelectrogenic bacteria are capable of converting the chemical energy of organic matter into electrical energy by transferring the electrons produced in the oxidation to the anode electrode.

    This project focused on developing a single device for nitrification, denitrification and carbon removal. Two double air-cathode single chamber MFCs are used to test the feasibility of this process that could replace the biological unit in a waste water treatment train.

    The cells tested in this study were manufactured with the purpose of achieving a high surface area on both the anode electrode (vitreous carbon foam) and the air-cathode electrodes (metallic mesh with diffusion layer and active layer) with different catalysts for the reduction reaction (cobalt and platinum). The bacterial biofilm growth is a fundamental step and the cells Open Circuit Potential was monitored during all the start-up period to determine the microorganism acclimation: a three days lag period was observed in both cells before the potential rise. The second cell was forced to reach higher voltage through an anode polarization and that seems to positively affect the biofilm stability at lower voltages transferring a greater amount of electrons and hence obtaining a higher current and power generation. For this reason after three weeks of inoculation the second cell reached an open circuit potential of 0.76 V which is a promising value for such a system.

    Electrochemical and biological tests were conduced in order to test the power production of the cell and the substrate removal from the waste water. Polarization curves were used to evaluate power generation (and the maximum production under a specific external load) and the cell voltage trend which is characterized by activation and ohmic losses: 32 mW/ and 41 mW/  are the power density normalized by cathode surface (72 ) reached by respectively first and second cell. The experimental conditions were varied from low to high temperature and from low to high inlet flow rate but the most affecting phenomenon seems to be the biofilm formation since significant voltage drops were noticed after long closed circuit operation. Higher cell voltage characterized the second cell thanks to more active cathode (platinum catalyst used) and more negative bacterial biofilm but a bigger drop in current generation over time affects the system performance and the most reliable reason is the shorter acclimation time compared to the first cell.

    Cyclic voltammetry tests were carried out on both electrodes to study the potential range of activity and determine an optimal operational voltage despite of mass transport or kinetic limitations.

    Substrate removal tests at different retention times in power generation conditions (external load 100 Ω) showed a relatively high total nitrogen consumption (maximum 72.2 %) for the first cell while lower values were achieved by the second system meaning that a longer acclimation period is beneficial for nitrifying and denitrifying bacteria to thrive on the cathode biofilm.

    Effluent pH level are almost similar to the initial values probably because of nitrification and denitrification protons offset.

  • 15.
    Cetecioglu, Zeynep
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Atasoy, Merve
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Biodegradation and inhibitory effects of antibiotics on biological wastewater treatment systems2018In: Toxicity and Biodegradation Testing, Humana Press, 2018, no 9781493974245, p. 29-55Chapter in book (Refereed)
    Abstract [en]

    Antibiotics are one of the most consumed drugs and have become new emerging pollutants in the environment as antibiotics lead to long-term adverse effects on the ecosystem. They are produced by bacteria to inhibit the growth of other bacteria in nature as a defense mechanism. Furthermore, after discovering their therapeutical features, synthetic production methods were developed. In general, antibiotics are widely used in human medicine, veterinary medicine, farming and aquaculture for the prevention and treatment of diseases. Approximately 90% of the consumed antibiotics are excreted via urinary or fecal pathways from the human body after partial, or no metabolism, and they are transferred to the domestic sewage plants or directly to the environment. Conventional biological treatment of domestic sewage provides very low—if any—reduction for the antibiotics, which usually by-pass treatment and accumulate in the receiving waters, sediments, plants, and animals. The concentration of these materials in domestic wastewaters and surface waters is observed in a range between 0.3 μg/L and 150 μg/L. However, pharmaceutical plants, hospitals, concentrated animal feeding operations, and aquaculture generate effluents having much higher antibiotics concentrations in the range 100–500 mg/L. Consequently, it is essential to gather information on the fate and effect of these compounds at high concentrations for setting the basis for related practical treatment schemes. Inhibitory action of the antibiotics is experimentally evaluated in two different approaches: Short-term (acute) and long-term (chronic) tests: Acute experiments involve a microbial community selected and sustained by the selected organic substrate in the system and not previously exposed to the inhibitor. In long-term experiments with continuous feeding of the inhibitor, the test may reflect, aside from changes in substrate removal and utilization, adaptation and/or resistance of the microbial community or even shifts in microbial composition in response to continuous exposure to the selected inhibitor. However, a full insight on the inhibitory action can only be acquired when the response of the microbial community is tested for both acute and chronic inhibition impacts. In this chapter, the most commonly used antibiotic classes such as β-lactams, tetracycline, macrolides, sulfonamides, quinolones are examined. Their fate and transformation during wastewater treatment as well as their inhibitory and toxic effects on the microbial community are discussed by using various toxicity and inhibition tests.

  • 16.
    Dremé, Maria
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    EXERGIOPTIMERING PÅ KÄPPALAVERKET2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Käppala wastewater treatment plant (WWTP) is situated on the island of Lidingö east of Stockholm. In 2009 the load to the plant was approximately 540 000 person equivalents (p.e). The Käppala WWTP is owned by the Käppala Association, which is a union of eleven municipalities in the northern and eastern parts of the Stockholm area, treat the waste water from those municipalities.

    Käppalaverket is aiming to continuously optimize its activities, regarding both environmental and economical aspects. An important factor in the optimization of Käppalaverket is to create a sewage treatment process that is as energy and resource efficient as possible. This implies a good utilization of the resources that reach the plant through the waste water in the form of organic material and heat, but also to exploit the products that are formed (e.g. sludge and biogas).

    One way of measuring and evaluating this resource efficiency is to establish an exergy balance over the system by converting all energy flows in and out of the system into their corresponding exergy values. Svenskt Vatten (The Swedish Water & Waste Water Association) is in the process of developing a benchmarking tool where these values are used to calculate indices [1]. These indices can then be used to make comparisons between the exergy efficiency of the Käppala WWTP and other plants.

    Within the scope of a master’s thesis in Chemical Engineering at the Royal Institute of Technology (KTH) in Stockholm, the above mentioned exergy balance and exergy indices have been calculated for both years 2009 and 2010. The results of these calculations for 2009 show that Käppalaverket reached a high degree of treatment, but its exergy efficiency was low compared to other waste water treatment plants. The main reason for this was that the Käppala WWTP until June 2010 used its biogas for production of district heating, which resulted in poor exergy indices. The results for 2010, when the plant started producing vehicle fuel, show that the Käppala WWTP has now improved its exergy efficiency, and consequently its exergy indices are also better.

    As a further part of the project, an exergy analysis of the current sludge dewatering process at the Käppala WWTP was performed. The factors taken into consideration were the demand of electricity and chemicals, decrease of sludge transports from the plant, and the use of sludge as a fertilizer. The exergy efficiency of this process was then compared to the exergy efficiency of two other options for dewatering of sludge. The conclusion that could be drawn from this comparison was that the current dewatering process is very exergy efficient, much thanks to the fact that the sludge is hygienized without the energy-intensive thermophilic digestion.

  • 17. Engqvist, A.
    et al.
    Stenström, Petter
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Pierce, Kena
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Modelling the effects of a pumping program for increasing water circulation in a semi-enclosed bay in the Stockholm archipelago2006In: Proceedings of the International Conference on Estuarine and Coastal Modeling, 2006, p. 253-269Conference paper (Refereed)
    Abstract [en]

    Brunnsviken in the inner Stockholm archipelago, close to the City of Stockholm and popular for recreational activities, is a semi-enclosed bay with a very narrow passage to the adjacent archipelago and consequently has a limited water exchange. Various attempts have been made over the past three decades to improve the water quality in the bay. Since 1986, the drinking water authorities of Stockholm withdraw bottom water by pumping it from one of the deep basins of the bay through a pipe to be eventually discharged into the nearest embayment of the archipelago. There are, however, some questions regarding the cost-benefit aspect of this strategy. In particular, it is unclear if the location and the rate of pumping are well chosen in order to increase the ventilation of the bay at large. In addition, it should be possible to eventually optimize the pumping schedule, so that these energy-demanding and thus costly efforts are concentrated to times when they act in concert with natural forcing to increase water exchange. To help improve the pumping program, a modelling project was started in spring 2004. First, a one-dimensional (1-D) layer model that resolves the bay into one basin with multiple-layer stratification was attempted. Second, a three-dimensional (3-D) model with the capacity to be run under non-hydrostatic assumptions was set up at high resolution to study a number of scenarios. Both models were forced by wind, river discharge, surface temperature and the exchange driven by density fluctuations across the boundary to the adjacent archipelago. In the 3-D model, the pumping is included as a virtual divergence of the flow at the location of the pipe. The main results are that the 1-D model performs considerably better than the 3-D model in simulating the measured salinity profiles, even though it does not resolve the basin in the horizontal direction. The poor performance of the 3-D model with regard to salinity is however mainly due to boundary problems: too little inflow of saline water through the narrow and shallow entrance channel, and underestimation of the freshwater supply. The dynamics of the thermocline is better captured by the 3-D model but can certainly also be improved.

  • 18.
    Engström, Emma
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Transport and Fate of Escherichia coli in Unsaturated Porous Media2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The unsaturated zone could provide an effective barrier against pathogenic microbes entering the groundwater. Knowledge relating to microbial fate in this zone is therefore important for increased understanding of groundwater vulnerability. This thesis examines the published literature that is related to the transport, retention and survival processes that apply to the fecal indicator bacterium Escherichia coli in unsaturated porous media. The main focus concerns the research findings under steady-state flow in homogeneous filter media, and under unfavorable attachment conditions, which are the most common in the natural environment. Experimental results in the literature for the pore-, column- and field-scale are examined and compared to commonly applied theories and modeling approaches. An analysis of the main factors that influence attenuation and biofilm formation is provided. Further, the findings are illustrated in a model of an unplanted, vertical flow constructed wetland. The results indicate that retention at the solid-air-water interface is a major attenuation process. In addition, they suggest that the flow velocity (as dependent on the grain size and the saturation) is a key influencing factor. However, it has not yet been established how the research findings relating to the main processes and influencing factors can be incorporated into predictive models; in the literature, a multitude of models have been proposed and alternative theories could describe the same observation. In this study, the transport and fate of Escherichia coli in different sand filters is, therefore, modeled using various literature models - derived under similar experimental conditions - in order to assess the possibility to compare and generalize the equations, evaluate their implications considering the different saturation settings and filter depths, and to define the spectra of the reduction efficiencies. It is discovered that the bacterial attenuation behaviors vary largely. This calls for clarification regarding the underlying processes. Future research is also recommended to include the ef-fects of structured filter media and sudden changes in the flow rate.

  • 19.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Modeling bacterial transport and removal in a constructed wetland system2010In: Proceedings of the COMSOL Conference, 2010, Paris, 2010Conference paper (Refereed)
  • 20.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    Predicting the transport and fate of Escherichia coli in unsaturated sand filters2011In: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009Article in journal (Other academic)
  • 21.
    Engström, Emma
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Thunvik, Roger
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Kulabako, Robinah
    Department of Civil Engineering, Makerere University, Kampala, Uganda.
    Balfors, Berit
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Management and Assessment.
    Escherichia coli transport and fate in unsaturated porous media: a literature review of experimental findings and theories relating to processes, models and influencing factors2011In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537Article in journal (Other academic)
  • 22.
    Fatima, Masoom
    et al.
    KTH, School of Chemical Science and Engineering (CHE).
    Farooq, R.
    Lindström, Rakel
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.
    Saeed, M.
    A review on biocatalytic decomposition of azo dyes and electrons recovery2017In: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 246, p. 275-281Article in journal (Refereed)
    Abstract [en]

    Discharge of waste water from textile industry during coloring processes contains high concentrations of biologically difficult-to-degrade dye chemicals along with antifouling agents. Azo dyes considered to be the largest class of synthetic dyes used in the textile industries and are present in significant amounts in its effluents. These are highly stable because of its complex aromatic structure and covalent azo bonds. Traditional physico-chemical methods are not considered sufficient because of their high cost, partial degradation and more sludge production. The use of biocatalysts for decolorization is a gaining momentum due to having redox-active molecules. Current review explored techniques for the decomposition of textile dyes, their merits, limitations and recommended the emerging microbial fuel cell technology followed by aerobic treatment for complete degradation of dye intermediate metabolites.

  • 23.
    Goralski, Alma
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Removal of pharmaceutical residues from wastewater2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today, pharmaceutical residues are widely found in nature as a cause of the extensive use of human and veterinary medicine. The pharmaceutical residues have shown to have a damaging impact on flora and fauna. Wastewater Treatment Plants (WWTPs), today, are not designed for pharmaceutical removal, which calls for new methods and the implementation of these to avoid increased concentrations of pharmaceutical residues in nature.

    This thesis addresses three main areas. Firstly, a pre-study regarding the prevalence of pharmaceutical residues at different parts of a WWTP and in the nearby river, secondly, an evaluation of removal of pharmaceutical residues using ozone and, thirdly, the construction of a pilot plant scale Activated Carbon (AC) unit and an evaluation of its capacity for pharmaceutical and ozone removal. This work was done in order to verify the quality of a future full-scale unit including the advanced techniques ozone and AC that will be implemented at a WWTP for pharmaceutical removal.

    The pre-study shows that the total concentration of the Active Pharmaceutical Ingredients (APIs) was largest at the inlet (93.8 mg/L) and decreased throughout the process steps to be the lowest at the outlet (5.6 mg/L). Paracetamol was found in the highest concentration (86.5 mg/L) at the inlet but could not be detected in the outlet. In the recipient none of the APIs could be found. However, caffeine was detected in the recipient.

    The pilot plant studies were performed in a batch process, one at high ozone generation and one at low ozone generation. The pilot test at high ozone generation showed that all of the measured APIs were below their Limit of Quantification (LOQ) after 2 minutes. The pilot test at low ozone generation showed a total API-removal of 44% after 7 minutes, 78% after 13 minutes, 97% after 20 minutes and more than 99% after 60 minutes. All of the APIs were below their LOQ after 180 min.

    The AC-filter construction mirrored the conditions within a full-scale unit as closely as possible and was scaled by the superficial velocity. The AC-filter showed an ozone removal of approximately 99% and removed all pharmaceutical residues apart from Ranitidine which was decreased by 76%.

  • 24.
    Grönlund, Lisa
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    OPTIMERING AV KVÄVEAVSKILJNINGEN PÅ AVLOPPSRENINGSVERKET I HALLSBERGS KOMMUN: EN TEKNISK-, EKONOMISK- OCH MILJÖMÄSSIG UTVÄRDERING2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The waste water treatment plant in Hallsberg municipal is situated adjacent to Hallsberg, with Ralaån as a recipient. The technique at the waste water treatment plant is based on the principles for a classical activated sludge treatment plant and includes mechanical treatment, chemical treatment, biological treatment, and a sludge treatment where the digestion of primary and secondary sludge is used for extraction of biogas.

    Hallsberg waste water treatment plant has during some time had problems with the nitrogen removal with high nitrogen emissions as a consequence. The target value has been exceeded a couple of times during the last years and in 2009 the limit value was exceeded as well. The target value for Hallsberg waste water treatment plant is 10 mgNH4-N/l as an average value per month, the limit value is set to 10 mg NH4-N/l, as an average value per year. Since the waste water treatment plant in Hallsberg not is operating at full capacity, a lowering of the nitrogen emissions is assumed to be possible though a trimming of the existing equipment and of the processes on the site. This assumption formed the basis for this thesis, designed to optimize the nitrogen removal at the waste water treatment plant in Hallsberg. A technical, economical and environmental evaluation was included in the optimization to improve the function of the plant. Extra evaluations were made in the energy- and chemical consumption in order to streamline the operations at the plant as much as possible. The project was carried out through an initial literature-investigation followed by a four week period of sampling and analyzing at the site. The data that form the conclusion in this project has also been collected through online measurements at the plant as well as through analyses of older samples.

    After analyzing the collected data, the reasons for the high emissions of nitrogen is thought to be due to a combination of reasons:

    -During the spring and the autumn the external intake of well sludge can lead to a direct release of sludge in to the plant. The change of nitrogen content will not give enough time for the nitrifying bacteria to acclimatize, with elevated emissions of nitrogen as a consequence.

    -The usage of simultaneous precipitation could lead to an irregular concentration of nitrogen released to the treatment plant from the digesters. This in turn could contribute to higher nitrogen emissions.

    -The irregularities of the usage of the centrifuge contribute to nitrogen irregularities and contribute to the difficulties of acclimatization of the nitrifying bacteria.

    -A high pre-precipitation of phosphorus and organic matter has contributed to a level of organic material in the denitrifikation below what is recommended.

    To sum up, further investigations are suggested in the above mentioned areas to make the operations at the plant carried trough at the lowest possible environmental and economically cost.

  • 25.
    Hamisi, Rajabu
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Renman, Agnieszka
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Wörman, Anders
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Modelling phosphorus sorption kinetics and the longevity of reactive filter materials used for on-sitewastewater treatment2019In: Water, ISSN 2073-4441, E-ISSN 2073-4441, Vol. 11, no 4, article id 811Article in journal (Refereed)
    Abstract [en]

    Use of reactive filter media (RFM) is an emerging technology in small-scale wastewater treatment to improve phosphorus (P) removal and filter material longevity for making this technology sustainable. In this study, long-term sorption kinetics and the spatial dynamics of sorbed P distribution were simulated in replaceable P-filter bags filled with 700 L of reactive material and used in real on-site treatment systems. The input data for model calibration were obtained in laboratory trials with Filtralite P®, Polonite® and Top16. The P concentration breakthrough threshold value was set at an effluent/influent (C/C 0 ) ratio of 1 and simulations were performed with P concentrations varying from 1 to 25 mg L -1 . The simulation results showed that influent P concentration was important for the breakthrough and longevity, and that Polonite performed best, followed by Top16 and Filtralite P. A 100-day break in simulated intermittent flow allowed the materials to recover, which for Polonite involved slight retardation of P saturation. The simulated spatial distribution of P accumulated in the filter bags showed large differences between the filter materials. The modelling insights from this study can be applied in design and operation of on-site treatment systems using reactive filter materials.

  • 26.
    Hermelin, Samuel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Suokko, Joel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Rening av kontaminerat vatten med hjälp av biomassa: En alternativ reningsmetod för metallkontaminerat vatten i Uganda2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att en hållbar utveckling ska kunna nås enligt de 17 miljömålen från Paris krävs en enkel och billig metod för vattenrening. Denna rapport behandlar en relativt oprövad metod som innebär att man ska rena metallförorenat vatten med hjälp av adsorptionsytor hos biomassa. Syftet med rapporten är att ta reda på ifall koppar- och koboltjoner skulle kunna bindas till vassväxten Cyperus papyrus och bomullsväxten Imperata cylindrica. Hur konkurrensen mellan kopparn och kobolten påverkar adsorptionen till biomassan samt vilken av biomassorna som lämpar sig bäst för rening skall också fastställas. Området som granskades var den koppar- och koboltförorenade floden River Nyamwamba i Uganda vilket gjorde att metallerna koppar och kobolt studerades. Biomassorna Cyperus papyrus och Imperata cylindrica växer i stor utsträckning i Uganda så dessa valdes ur ett hållbarhetsperspektiv då eventuella transporter kan minimeras. Adsorptionsförmågan av metallerna bestämdes genom en laboration där biomassorna kunde adsorbera mellan 45,55 - 69,84 % av kobolten och 63,74 -77,54 % av kopparn hos de fyra olika lösningarna som testades. Imperata cylindrica visade sig ha en något bättre adsorptionsförmåga. Möjliga metoder som skulle kunna implementeras i samhället kan vara filter tillverkade av biomassa men det krävs fortfarande mer forskning inom området innan dessa kan tas i bruk. 

  • 27.
    Hossain, Mohammed
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. NGO Forum Publ Hlth, Dhaka 1207, Bangladesh.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Frape, Shaun K.
    Ahmed, Kazi Matin
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Hasan, M. Aziz
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Ramboll Sweden AB, Soil & Water Environm, SE-10462 Stockholm, Sweden.
    Shahiruzzaman, Mohammad
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Intermediate Deep Aquifer (IDA) : A potential source for Arsenic-safe and low-Manganese drinking waterManuscript (preprint) (Other academic)
  • 28.
    Hossain, Mohammed
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. NGO Forum Publ Hlth, Dhaka 1207, Bangladesh.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Frape, Shaun K.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Islam, M. Mainul
    Rahman, M. Moklesur
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Ramboll Sweden AB, Soil & Water Environm, SE-10462 Stockholm, Sweden.
    Hasan, M. Aziz
    Ahmed, Kazi Matin
    Sediment color tool for targeting arsenic-safe aquifers for the installation of shallow drinking water tubewells2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 493, p. 615-625Article in journal (Refereed)
    Abstract [en]

    In rural Bangladesh, drinking water supply mostly comes from shallow hand tubewells installed manually by the local drillers, the main driving force in tubewell installation. This study was aimed at developing a sediment color tool on the basis of local driller's perception of sediment color, arsenic (As) concentration of tubewell waters and respective color of aquifer sediments. Laboratory analysis of 521 groundwater samples collected from 144 wells during 2009 to 2011 indicate that As concentrations in groundwater were generally higher in the black colored sediments with an average of 239 mu g/L. All 39 wells producing water from red sediments provide safe water following the Bangladesh drinking water standard for As (50 mu g/L) where mean and median values were less than the WHO guideline value of 10 mu g/L. Observations for off-white sediments were also quite similar. White sediments were rare and seemed to be less important for well installations at shallow depths. A total of 2240 sediment samples were collected at intervals of 1.5 m down to depths of 100 m at 15 locations spread over a 410 km(2) area in Matlab, Bangladesh and compared with the Munsell Color Chart with the purpose of direct comparison of sediment color in a consistent manner. All samples were assigned with Munsell Color and Munsell Code, which eventually led to identify 60 color shade varieties which were narrowed to four colors (black, white, off-white and red) as perceived and used by the local drillers. During the process of color grouping, participatory approach was considered taking the opinions of local drillers, technicians, and geologists into account. This simplified sediment color tool can be used conveniently during shallow tubewell installation and thus shows the potential for educating local drillers to target safe aquifers on the basis of the color characteristics of the sediments.

  • 29.
    Hossain, Mohammed
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. NGO Forum Publ Hlth, Dhaka 1207, Bangladesh.
    Frape, Shaun K.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Rahman, M. Moklesur
    Alam, M. S.
    Hoque, M. A.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Hasan, M. Aziz
    Ahmed, Kazi Matin
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. Ramboll Sweden AB, Soil & Water Environm, SE-10462 Stockholm, Sweden.
    Hydrogeological variation in Shallow, Intermediate and Deep Aquifers in Matlab of Southeastern Bangladesh: implications for the installation of arsenic-safe drinking water tubewells and their sustainabilityManuscript (preprint) (Other academic)
  • 30.
    Khan, MD. Ershad Ullah
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Martin, Andrew R.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Optimization of hybrid renewable energy polygeneration system with membrane distillation for rural households in Bangladesh2015In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 93, p. 1116-1126Article in journal (Refereed)
    Abstract [en]

    Despite the country's rural electrification program, kerosene is the predominant source for lighting, and woody biomass is virtually the only option available for cooking. The rural population also struggles with unsafe drinking water in terms of widespread arsenic contamination of well water. Biogas plants and pV are individually impractical to serve both cooking, lighting and water purification systems, and their combined applications are extremely limited. This study considers a holistic approach towards tackling both of these issues via integrated renewable energy-based polygeneration employed at the village level. The polygeneration unit under consideration provides electricity via a pV array and animal and agriculture waste-fed digester, which in turn is coupled to a gas engine. Excess digester gas is employed for cooking and lighting, while waste heat from the process drives a membrane distillation unit for water purification. Technical assessments and optimization have been conducted with HOMER (Hybrid Optimization of Multiple Energy Resources). Results show that daily electricity demand can be met with such a system while simultaneously providing 0.4 m3 cooking fuel and 2e3 L pure drinking water. Cost estimates indicate that this approach is highly favorable to other renewable options. The pay back period of such system is between 3 and 4 years.

  • 31.
    Kharazmi, Parastou
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Evaluation of Innovative Rehabilitation Technologies Utilising Polymer Composites for Aging Sewer Systems2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Water and wastewater sewer system maintenance is among the costliest aspects of infrastructure investment. The replacement of deteriorated lines is a difficult and expensive process that causes community disturbance and is generally not conducted fast enough to meet demand. To keep up with the rate of deterioration, the use of alternative rehabilitation technologies using polymer linings has increased significantly in recent years, both within Sweden and worldwide. Compared to the traditional pipe replacement method, these technologies are cost-effective, create less community disturbance, and offer a quick return to the service for the line. The main function of polymeric lining is to stabilise the condition of the pipeline, eliminate deterioration, and thereby extend the pipeline’s service life. Although rehabilitation technologies employing polymeric systems have been in use for over 30 years, there have been few technical assessments of either these technologies or the materials involved. Data gathered through the evaluation of these innovative technologies can make their benefits and limitations more widely understood, and can also be used to increase the effectiveness of the rehabilitation process in future.

    The main objective of this work was to contribute to an improved understanding of the most commonly used materials and methods employed in rehabilitation of wastewater and other applicable sewer lines in residential buildings in Sweden. The primary objective was not to prove that the emerging rehabilitation technologies work, but rather to increase knowledge of their weaknesses and strengths, identify any issues, and provide a technical assessment to support realistic expectations of pipeline rehabilitation. Gathering technical information in this way will help with the planning of future investigations; moreover, collecting extensive data will help to increase the effectiveness of the renewal works, aid progress in the field, and improve predictions regarding longevity and service life.

    As pipeline rehabilitation is still considered novel, and owing to the general lack of available data on the subject, a multi-approach study was carried out: this included evaluation of the polymeric materials’ performance in the presence of deteriorative factors, assessing the in-service state of the materials and lined sewers previously installed, monitoring the level of quality control implemented during previous rehabilitation works, and evaluating the environmental impacts of using pipe-lining technologies compared to pipe replacement. The techniques discussed included rehabilitation with epoxy and polyester resin-based lining materials, applied with brush-on and spray-on techniques, and cured-in-place pipe lining (installed by sending a resin-impregnated flexible tube inside the host pipe).

    Degradation of the resin-based lining materials was investigated via artificial aging involving immersion in water at elevated temperatures. The changes in materials that occurred during accelerated laboratory aging were tracked by means of various tests, including thermal and mechanical analyses, water absorption measurements and microscopy. The analysis focused on reinforced polyester-based and toughened epoxy-based lining materials in order to gain a better understanding of their performance as pipe lining. Moreover, the previously installed lined pipes and lining materials were also studied during laboratory examinations to evaluate the in-service performance of the materials and techniques under operating conditions over time, as well as to identify common defects. The state of the materials and the lined pipe were studied by means of different investigative methods, including visual inspection, microscopy, Fourier transform infrared spectroscopy, thickness measurement, thermal and mechanical analyses. This PhD work also includes an investigation to determine the level of quality control carried during some previous rehabilitation works. Data on the quality evaluation of previous rehabilitation works were gathered during visits to the work sites, as well as by analysing lined pipes that had already been installed. Finally, a comparative life-cycle assessment was undertaken to compare the environmental impacts of pipe replacement with those of alternative innovative rehabilitations, such as CIPP and coatings with polyester and epoxy polymeric systems. Data obtained from an LCA tool were used to facilitate comparison from an environmental perspective.

    Results from artificial aging in the lab indicated that the properties of polymeric lining materials changed significantly when high temperatures were combined with water exposure. However, the aging testing conducted for this study also found that the materials performed relatively well at temperatures close to the average temperatures inside sewerage systems. The results revealed that the polyester-based lining material was less sensitive when compared with epoxy-based lining materials during stimulated aging. Moreover, results from the in-service field demonstration (involving examination of 12 samples with up to 10 years of service, including reinforced polyester and modified epoxy linings or cured-in-place pipe (CIPP) lining) showed minimal evidence that the materials underwent significant deterioration after installation; instead, a majority of the common defects were found to be related to poor-quality installation practices. Because very few field samples were available to study, conclusions regarding overall performance could not be drawn. However, there is no evidence that these materials will not perform as expected during their service life when properly installed.

    Evaluating quality control of previous rehabilitation work revealed a gap between theory and practice where the level of quality control and documentation was concerned; furthermore, it also emerged that quality control and documentation is crucial to both the prevention of common issues and the overall effectiveness of the rehabilitation. Accordingly, a series of recommendations regarding the development of comprehensive quality control and quality assurance procedures (QC/QA) are provided in this work. These recommendations highlight the aspects that are most important to consider at each of several key stages (before installation, during installation, and after rehabilitation work is completed).

    Results from comparative life-cycle assessment (LCA) showed that alternative technologies, including cured-in-place (flexible sleeve) and coating techniques, have some advantages over pipe replacement from an environmental perspective. However, the choice to use one rehabilitation technology over another is a multi-stage decision-making process that should not be based solely on a single factor.

    This PhD work promotes an improved understanding of the limitations and benefits of polymeric lining through the testing performed and analyses conducted. This work highlights the need for improved quality control, and further suggests that developing a detailed and comprehensive quality control plan for each technology would provide higher and more consistent quality overall. The study also demonstrates that the long-term strength of any rehabilitation work depends on various factors, and that selecting one method over another must be a process based on extensive knowledge and understanding of each rehabilitation technology. No evidence was found to indicate that the materials could not perform well under working conditions if selected and installed appropriately. However, a larger number of field samples with longer in-service time and a more detailed technical history, along with a more extended experimental plan for laboratory investigations based on the results of this PhD work, will allow for the gathering of the data required to answer questions regarding life expectancy with a higher degree of certainty.

  • 32. Kibria, M. G.
    et al.
    Kirk, M. F.
    Datta, S.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Hossain, Mohammed
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    von Brömssen, Mattias
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Jacks, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Ahmed, K. M.
    Hydrogeochemistry and microbial geochemistry on different depth aquifer sediments from Matlab, Bangladesh2014In: 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, 2014, p. 101-103Conference paper (Refereed)
    Abstract [en]

    Arsenic (As) poses the greatest hazard towards drinking water quality in Bangladesh. Tubewell drinking water is one of the main sources for household based water options in rural Bangladesh. Our study area is in Matlab Upazila, in Bangladesh. The overall objective of this research and the SASMIT project is to develop a community based initiative for sustainable As mitigation by developing a sediment color based tool for the local drillers prioritizing on the hydrogeological and biogeochemical investigations. For this purpose we analyzed different depth colored sediments and water for find out the sustainable low Arsenic contaminated aquifer.

  • 33. Kumar, M.
    et al.
    Ramanathan, A. L.
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Evaluation of arsenic and its controlling factors in aquifer sands of district Samastipur, Bihar, India2014In: 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. 108-109Conference paper (Refereed)
    Abstract [en]

    A set of 96 water samples from shallow tubewells and 14 sediment samples from Samastipur district to know the level of arsenic (As) and its controlling factors were analyzed. Groundwater samples were collected from tubewells of different depths, and a wide range of concentrations in the range 0.19-135 μg L-1 was found. Scanning electron micrograph study of the sediments shows intense chemical weathering. Present study also support reductive dissolution of FeOOH triggered by organic matter oxidation as an As mobility factor in the aquifer sands.

  • 34.
    Kårelid, Victor
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Towards application of activated carbon treatment for pharmaceutical removal in municipal wastewater2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Many pharmaceuticals are found in municipal wastewater effluents due to their persistence in the human body as well as in conventional wastewater treatment processes. This discharge to the environment can lead to adverse effects in aquatic species, such as feminization of male fish. During the past decade, these findings have spawned investigations and research into suitable treatment technologies that could severely limit the discharge. Adsorption onto activated carbon has been identified as one of the two main technologies for implementation of (future) full-scale treatment.

    Recent research has put a closer focus on adsorption with powdered activated carbon (PAC) than on granular activated carbon (GAC). Studies where both methods are compared in parallel operation are thus still scarce and such evaluation in pilot-scale was therefore a primary objective of this thesis. Furthermore, recirculation of PAC can be used to optimize the treatment regarding the carbon consumption. Such a setup was evaluated as a separate treatment stage to comply with Swedish wastewater convention. Additionally, variation of a set of process parameters was evaluated.

    During successive operation at three different wastewater treatment plants an overall pharmaceutical removal of 95% could consistently be achieved with both methods. Furthermore, treatment with GAC was sensitive to a degraded effluent quality, which severely reduced the hydraulic capacity. Both treatment methods showed efficient removal of previously highlighted substances, such as carbamazepine and diclofenac, however in general a lower adsorption capacity was observed for GAC. By varying the input of process parameters, such as the continuously added dose or the contact time, during PAC treatment, a responsive change of the pharmaceutical removal could be achieved. The work in this thesis contributes some valuable field experience towards wider application of these treatment technologies in full-scale.

  • 35.
    Kårelid, Victor
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Larsson, Gen
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Björlenius, Berndt
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Effects of recirculation in a three-tank pilot-scale system for pharmaceutical removal with powdered activated carbon2017In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 193, no May, p. 163-Environmental Impact Optimization of Reinforced Concrete Slab Frame BridgesArticle, review/survey (Refereed)
    Abstract [en]

    The removal of pharmaceutically active compounds by powdered activated carbon (PAC) in municipal wastewater is a promising solution to the problem of polluted recipient waters. Today, an efficient design strategy is however lacking with regard to high-level overall, and specific, substance removal in the large scale. The performance of PAC-based removal of pharmaceuticals was studied in pilot-scale with respect to the critical parameters; contact time and PAC dose using one PAC product selected by screening in bench-scale. The goal was a minimum of 95% removal of the pharmaceuticals present in the evaluated municipal wastewater. A set of 21 pharmaceuticals was selected from an initial 100 due to their high occurrence in the effluent water of two selected wastewater treatment plants (WWTPs) in Sweden, whereof candidates discussed for future EU regulation directives were included. By using recirculation of PAC over a treatment system using three sequential contact tanks, a combination of the benefits of powdered and granular carbon performance was achieved. The treatment system was designed so that recirculation could be introduced to any of the three tanks to investigate the effect of recirculation on the adsorption performance. This was compared to use of the setup, but without recirculation. A higher degree of pharmaceutical removal was achieved in all recirculation setups, both overall and with respect to specific substances, as compared to without recirculation. Recirculation was tested with nominal contact times of 30, 60 and 120 min and the goal of 95% removal could be achieved already at the shortest contact times at a PAC dose of 10–15 mg/L. In particular, the overall removal could be increased even to 97% and 99%, at 60 and 120 min, respectively, when the recirculation point was the first tank. Recirculation of PAC to either the first or the second contact tank proved to be comparable, while a slightly lower performance was observed with recirculation to the third tank. With regards to individual substances, clarithromycin and diclofenac were ubiquitously removed according to the set goal and in contrast, a few substances (fluconazole, irbesartan, memantine and venlafaxine) required specific settings to reach an acceptable removal.

  • 36.
    Kårelid, Victor
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Larsson, Gen
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Björlenius, Berndt
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Pilot-scale removal of pharmaceuticals in municipal wastewater: Comparison of granular and powdered activated carbon treatment at three wastewater treatment plants2017In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 193, no -1, p. 491-502Article in journal (Refereed)
    Abstract [en]

    Adsorption with activated carbon is widely suggested as an option for the removal of organic micropollutants including pharmaceutically active compounds (PhACs) in wastewater. In this study adsorption with granular activated carbon (GAC) and powdered activated carbon (PAC) was analyzed and compared in parallel operation at three Swedish wastewater treatment plants with the goal to achieve a 95% PhAC removal. Initially, mapping of the prevalence of over 100 substances was performed at each plant and due to low concentrations a final 22 were selected for further evaluation. These include carbamazepine, clarithromycin and diclofenac, which currently are discussed for regulation internationally. A number of commercially available activated carbon products were initially screened using effluent wastewater. Of these, a reduced set was selected based on adsorption characteristics and cost. Experiments designed with the selected carbons in pilot-scale showed that most products could indeed remove PhACs to the target level, both on total and individual basis. In a setup using internal recirculation the PAC system achieved a 95% removal applying a fresh dose of 15–20 mg/L, while carbon usage rates for the GAC application were much broader and ranged from <28 to 230 mg/L depending on the carbon product. The performance of the PAC products generally gave better results for individual PhACs in regards to carbon availability. All carbon products showed a specific adsorption for a specific PhAC meaning that knowledge of the target pollutants must be acquired before successful design of a treatment system. In spite of different configurations and operating conditions of the different wastewater treatment plants no considerable differences regarding pharmaceutical removal were observed.

  • 37.
    Lakshmanan, Ramnath
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Application of magnetic nanoparticles and reactive filter materials for wastewater treatment2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Lately sewage wastewater treatment processes (WWTP) are facing challenges due to strict regulations in quality of effluent standards and waste production. The reuse of wastewater treatment effluents is rapidly gaining attention as a means of achieving sustainable water supply. Therefore, new methods are required to achieve an efficient WWTP. The foremost emphasis of the present study is to investigate filter materials, synthesis, characterization, and application of magnetic nanoparticles (NPs) for WWTP. Primarily commercially available reactive filter materials such as Polonite and Sorbulite were tested for the effective reduction of contaminants in recirculation batch mode system. Secondly, the magnetic nanoparticles were synthesized using different techniques such as water-in-oil (w/o) microemulsion and co- precipitation methods and testing for their ability to remove contaminants from wastewater. Thirdly, toxicity test of magnetic NPs were performed using human keratinocytes (HaCaT) and endothelial (HMEC-1) cells (Papers I-VII).

    The magnetic iron oxide nanoparticles (MION) synthesized using the co-precipitation method were further functionalized with tri-sodium citrate (TSC), 3-aminopropyl triethoxysilane (APTES), polyethylenimine (PEI) and chitosan. The functionalized MION were further characterized prior to use in removal of contaminants from wastewater. The sewage wastewater samples were collected from Hammarby Sjöstadsverk, Sweden and analyses were performed for the reduction of turbidity, color, total nitrogen, total organic carbon, phosphate and microbial content on the retrieval day.

    The experimental results imply that Polonite and Sorbulite require high pH for the efficient reduction of phosphate and the reduction of microbes. Microemulsion prepared magnetic nanoparticles (ME-MION) showed ≈100% removal of phosphate in 20 minutes. Results from TEM implied that the size of magnetic Nps were around 8 nm for core (uncoated MION), TSC (11.5 nm), APTES (20 nm), PEI (11.8 nm) and chitosan (15 nm). Optimization studies using central composite face centered (CCF) design showed the potential of magnetic nanoparticles for the removal of turbidity (≈83%) and total nitrogen (≈33%) in 60 minutes. The sludge water content was reduced significantly by ≈87% when magnetic NPs were used whilst compared to the chemical precipitant used in WWTP. PEI coated MION showed ≈50% removal of total organic carbon from wastewater in 60 minutes. Effluents from wastewater treated with magnetic NPs were comparable with effluent from the present WWTP. There was no significant change observed in mineral ion concentration before and after treatment with MION. In addition, toxicity results from HMEC-1 and HaCaT cells revealed no formation of reactive oxygen species in the presence of magnetic NPs. Furthermore, laboratory experiments revealed the effectiveness and reusability of magnetic NPs. Thus magnetic NPs are a potential wastewater treatment agent and can be used for effective removal of contaminants, thereby reducing the process time, sludge water content and complex process steps involved in conventional WWTP.

  • 38.
    Lakshmanan, Ramnath
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Bayat, Narges
    Stockholm University, Department of Biochemistry and Biophysics.
    R-Lopes, Viviana
    Linköping University, Department of Clinical and Experimental Medicine.
    Cristobal, Susana
    Linköping University, Department of Clinical and Experimental Medicine.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Synthesis, characterization and toxicity assessment of magnetic nanoparticles on skin and endothelial cells in vitro: water treatment applicationManuscript (preprint) (Other academic)
  • 39.
    Lakshmanan, Ramnath
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Effective water content reduction in sewage wastewater sludge using magnetic nanoparticlesManuscript (preprint) (Other academic)
  • 40.
    Lakshmanan, Ramnath
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Effective water content reduction in sewage wastewater sludge using magnetic nanoparticles2014In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 153, p. 333-339Article in journal (Refereed)
    Abstract [en]

    The present work compares the use of three flocculants for sedimentation of sludge and sludge water content from sewage wastewater i.e. magnetic iron oxide nanoparticles (MION), ferrous sulfate (chemical) and Moringa crude extract (protein). Sludge water content, wet/dry weight, turbidity and color were performed for, time kinetics and large-scale experiment. A 30% reduction of the sludge water content was observed when the wastewater was treated with either protein or chemical coagulant. The separation of sludge from wastewater treated with MION was achieved in less than 5. min using an external magnet, resulted in 95% reduction of sludge water content. Furthermore, MION formed denser flocs and more than 80% reduction of microbial content was observed in large volume experiments. The results revealed that MION is efficient in rapid separation of sludge with very low water content, and thus could be a suitable alternative for sludge sedimentation and dewatering in wastewater treatment processes.

  • 41.
    Lakshmanan, Ramnath
    et al.
    KTH, School of Biotechnology (BIO), Bioprocess Technology (closed 20130101).
    Okoli, Chuka
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology. KTH, School of Biotechnology (BIO), Bioprocess Technology (closed 20130101).
    Boutonnet, Magali
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Järås, Sven
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Bioprocess Technology (closed 20130101).
    Effect of Magnetic Iron Oxide Nanoparticles for Surface Water Treatment: Trace Minerals and MicrobesManuscript (preprint) (Other academic)
  • 42.
    Lakshmanan, Ramnath
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Okoli, Chuka
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Boutonnet, Magali
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Järås, Sven
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Microemulsion prepared magnetic nanoparticles for phosphate removal: Time efficient studies2014In: Journal of Environmental Chemical Engineering, ISSN 2213-3437, Vol. 2, no 1, p. 185-189Article in journal (Refereed)
    Abstract [en]

    The present study investigates the effective removal of phosphate in sewage wastewater using magnetic iron oxide nanoparticles (MION). The microemulsion-prepared magnetic iron oxide nanoparticles (ME-MION) of around 7-10 nm was synthesized using water-in-oil microemulsion method. The interaction of ME-MION and phosphate was studied using In situ FT-IR technique. Batch experiments were carried out with wastewater to determine the conc. and time efficiency using ME-MION for removal of phosphate. The vibration peak at 1004 cm-1 and the presence of hydroxyl group (OH-) at 3673 cm-1 confirms the binding of phosphate to ME-MION. ME-MION with 0.44 g L-1 exhibited more than 95% phosphate reduction in 5 min and close to 100% in 20 min. Conversely the experimental data obtained has been fitted with Langmuir isotherm model and also exhibited high correlation coefficients. The ME-MION was regenerated and can be reused for minimum 5 consecutive times. Efficient and fast reduction of phosphate was attained while the recovery of nanoparticles was achieved by an external magnetic field. To the author's knowledge, this is the first report that underscores around 100% phosphate removal from wastewater using ME-MION in 20 min. The approach utilized in this study offers a potential technique in the reduction of phosphate in wastewater whilst, reducing the time and reuse of nanoparticles.

  • 43.
    Lakshmanan, Ramnath
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Rajaraman, Premanand
    Sri Sairam Engineering College, Department of Physics.
    Okoli, Chuka
    KTH, School of Biotechnology (BIO), Industrial Biotechnology. KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Boutonnet, Magali
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Järås, Sven
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Application of Magnetic Nanoparticles for the removal of turbidity and total nitrogen from sewage wastewater: Modelling studiesManuscript (preprint) (Other academic)
  • 44.
    Lakshmanan, Ramnath
    et al.
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Sanchez-Dominguez, Margarita
    Centro de Investigacion en Materials Avanzados (CIMAV) S.C., Mexico.
    Matutes-Aquino, Jose
    Centro de Investigacion en Materials Avanzados (CIMAV) S.C., Mexico.
    Wennmalm, Stefan
    KTH, School of Engineering Sciences (SCI), Applied Physics, Experimental Biomolecular Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Kuttuva Rajarao, Gunaratna
    KTH, School of Biotechnology (BIO), Industrial Biotechnology.
    Removal of total organic carbon from sewage wastewater using poly(ethylenimine)-functionalized magnetic nanoparticles2014In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 30, no 4, p. 1036-1044Article in journal (Refereed)
    Abstract [en]

    The increased levels of organic carbon in sewage wastewater during recent years impose a great challenge to the existing wastewater treatment process (WWTP). Technological innovations are therefore sought that can reduce the release of organic carbon into lakes and seas. In the present study, magnetic nanoparticles (NPs) were synthesized, functionalized with poly(ethylenimine) (PEI), and characterized using TEM (transmission electron microscopy), X-ray diffraction (XRD), FTIR (Fourier transform infrared spectroscopy), CCS (confocal correlation spectroscopy), SICS (scattering interference correlation spectroscopy), magnetism studies, and thermogravimetric analysis (TGA). The removal of total organic carbon (TOC) and other contaminants using PEI-coated magnetic nanoparticles (PEI-NPs) was tested in wastewater obtained from the Hammarby Sjöstadsverk sewage plant, Sweden. The synthesized NPs were about 12 nm in diameter and showed a homogeneous particle size distribution in dispersion by TEM and CCS analyses, respectively. The magnetization curve reveals superparamagnetic behavior, and the NPs do not reach saturation because of surface anisotropy effects. A 50% reduction in TOC was obtained in 60 min when using 20 mg/L PEI-NPs in 0.5 L of wastewater. Along with TOC, other contaminants such as turbidity (89%), color (86%), total nitrogen (24%), and microbial content (90%) were also removed without significant changes in the mineral ion composition of wastewater. We conclude that the application of PEI-NPs has the potential to reduce the processing time, complexity, sludge production, and use of additional chemicals in the WWTP.

  • 45.
    Lindvall, Sara
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Avloppsrening med mikrobiella bränsleceller: En litteraturstudie om den senaste forskningens framsteg2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wastewater treatment is a crucial function in the urban society. With increasing population the need for energy efficient and ecologically sus- tainable solutions for water recovery will grow. Microbial Fuel Cells (MFC) are a promising technique with a potential to contribute to solv- ing this task, which is why they have been under extensive studies for several years in the context of wastewater treatment and energy recov- ery. A MFC designed for wastewater treatment consists of an electrolysis cell that uses wastewater as electrolyte, turning the chemical energy into electrical energy whilst microbes digests the nutrients and organic sub- stances. Some specific microbes, electrochemically active bacterias, are capable of anaerobic digestion and when the organic loadings are con- sumed, electrons and protons are released and a current can be collected from the fuel cell. This paper is a review of the most recent research focused on solving the critical problems that still prohibit a large scale usage of MFC for wastewater treatment. The most prominent issues are related to high initial costs och operational stability and the aim of this study is to summarize the state of art regarding cost effective materials and configurations and also to discuss what the future role of MFC in wastewater treatment might be. Due to the limited format only the eco- nomical and ecological aspects of sustainability is regarded. The results from this review indicates that the most cost effective basic configuration of MFC is membranless and free from expensive catalysts. Many studies show that the use of biological catalysts, such as microbial biofilm on the electrode surfaces, is a low-cost and effective way of stimulating the oxidation-reduction-reactions that drives the MFC. Also the use of air- cathodes, where the cathode is exposed to the air in order to stimulate oxygen reduction, instead of energy consuming air pump, is a promising way forward. Recently the use of natural materials, such as loofah and clay ware, have been studied with various results, and if the operational stability and overall performance could be enhanced this might well be a sustainable rout in research. Another strong trend is the use of cole-, metaloxide- or polymerbased nanomaterials which have a documented ability to increase both electric and purifying efficiencies, but the ecolog- ical sustainability regarding nanomaterials is a complex question which is not answered in this paper. Altogether, the research covered in this work shows that large scale wastewater treatment with MFC alone not at all is near at hand. However, some minor improvements have been made regarding cost effective and ecologically sustainable materials and con- figurations for MFC, and these findings could well be used in a context where MFC is integrated with other techniques, such as a Membrane Bio Reactor or Constructed Wetland, in order to take advantage of the syner- gistic effects that has been noticed in several studies. This might be the most reasonable role for MFC to play in the future wastewater treatment business, thereby contributing to the global strive for sustainability. 

  • 46. Maity, J. P.
    et al.
    Hsu, C. -M
    Lin, T. -J
    Lee, W. -C
    Bhattacharya, Prosun
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Water and Environmental Engineering.
    Bundschuh, Jochen
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. University of Southern Queensland, Australia.
    Chen, C. -Y
    Removal of fluoride from water through bacterial-surfactin mediated novel hydroxyapatite nanoparticle and its efficiency assessment: Adsorption isotherm, adsorption kinetic and adsorption Thermodynamics2018In: Environmental Nanotechnology, Monitoring and Management, ISSN 2215-1532, Vol. 9, p. 18-28Article in journal (Refereed)
    Abstract [en]

    Fluoride contamination in water due to natural and anthropogenic activities has been documented as serious problems worldwide commanding a major threat to the environment. Present study focuses to synthesis bacterial-surfactin (Bacillus subtilis) mediated nano-hydroxyapatite (HAp), novel adsorbents for defluoridation. HAp particle size and morphology were controlled by varying temperature of 90–150 °C and pH of 7–11, respectively. The TEM and SEM micrographs reveal that the short-rod particle is observed 20–30 nm at 90 °C and pH 11. The ratio between the length (nm) and width (nm) of nanoparticle are decreased from 4.17 to 1.65 with increasing pH (7–11). The selected area diffraction (SAD) of particles are indicated uniform rod-like monocrystals. The XRD and FTIR observations were indicated the synthesized HAp nanoparticles were well-crystallized with purity phase and high quality. The study reflected that the fluoride removal from contaminated water by HAp was increased significantly (R2 = 99) with the increasing adsorbent concentration, temperature and time, with two-step adsorption process as the first portion a rapid adsorption occurs during first 90 min after which equilibrium is slowly achieved. The adsorption process is closer to Freundlich isotherm (R2 &gt; 98) than to Langmuir isotherm (R2 ≈ 92), indicating HAp as a good adsorbent (n &gt; 3). Above 97% of fluoride removal were noticed at a HAp dose of 0.06 g/10 mL. The adsorption kinetics more fit with pseudo-second-order (R2= 99) in compare to pseudo-first-order (R2 ≈ 91). The slope and intercept of Arrhenius equation indicated the activation/adsorption energy (Ea) of 3.199 kJ/mol and frequency factor (A) of 1.78 1/s. Adsorption thermodynamic parameters (free energy (ΔG &lt; 0), enthalpy (ΔH &gt; 0) and entropy (ΔS &gt; 0)) indicates the spontaneous and endothermic reactions of the adsorption process. Thus, newly synthesized HAp nanoparticles exhibit as a good adsorbent for fluoride removal, theoretically and experimentally being applicable for environmental pollution control.

  • 47.
    Malovanyy, Andriy
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Anammox-based systems for nitrogen removal from mainstream municipal wastewater2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Nitrogen removal from municipal wastewater with the application of deammonification process offers an operational cost reduction, especially if it is combined with a maximal use of organic content of wastewater for biogas production. In this thesis, two approaches for integration of the deammonification process into the municipal wastewater treatment scheme were studied.

    The first approach is based on ammonium concentration from municipal wastewater by ion exchange followed by biological removal of ammonium from the concentrated stream by deammonification process. Experiments with synthetic and real municipal wastewater showed that strong acid cation resin is suitable for ammonium concentration due to its high exchange capacity and fast regeneration. Since NaCl was used for regeneration of ion exchange materials, spent regenerant had elevated salinity. The deammonification biomass was adapted to NaCl content of 10-15 g/L by step-wise salinity increase. The technology was tested in batch mode with 99.9 % of ammonium removal from wastewater with ion exchange and up to 95 % of nitrogen removal from spent regenerant by deammonification process.

    The second studied approach was to apply anammox process to low-concentrated municipal wastewater in a moving bed biofilm reactor (MBBR) and integrated fixed film activated sludge (IFAS) system without a pre-concentration step. After a 5 months period of transition to mainstream wastewater the pilot plant was operated during 22 months and stable performance of one-stage deammonification was proven. Clear advantage of IFAS system was shown. The highest stable nitrogen removal efficiency of 70 % and a nitrogen removal rate of 55 g N/(m3·d) was reached. Moreover, the influence of operation conditions on competition between ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) was studied by literature review, batch tests and continuous pilot plant operation.

  • 48.
    Marques, Marcia
    et al.
    KTH, Superseded Departments (pre-2005), Chemical Engineering and Technology.
    Da Costa, M. F.
    Mayorga, M. I. D. O.
    Pinheiro, P. R. C.
    Water environments: Anthropogenic pressures and ecosystem changes in the Atlantic drainage basins of Brazil2004In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 33, no 1-2, p. 68-77Article in journal (Refereed)
    Abstract [en]

    Densely occupied drainage basins and coastal zones in developing countries that are facing economic growth are likely to suffer from moderate to severe environmental impacts regarding different issues. The catchment basins draining towards the Atlantic coast from northeastern to southern Brazil include a wide range of climatic zones and diverse ecosystems. Within its borders lies the Atlantic rain forest, significant extensions of semiarid thorn forests (caatinga), vast tree and scrub woodlands (cerrado) and most of the 6670 km of the Brazilian coast and its marine ecosystems. In recent decades, human activities have increasingly advanced over these natural resources. Littoralization has imposed a burden on coastal habitats and communities. Most of the native vegetation of the cerrado and caatinga was removed and only 7% of the original Atlantic rainforest still exists. Estuaries, bays and coastal lagoons have been irreversibly damaged. Land uses, damming and water diversion have become the major driving forces for habitat loss and aquatic ecosystem modification. Regardless of the contrast between the drought-affected northeastern Brazil and the much more prosperous and industrialized southeastern/southern Brazil, the impacts on habitat and communities were found equally severe in both cases. Attempts to halt environmental degradation have not been effective. Instead of focusing on natural resources separately, it is suggested that more integrated environmental policies that focus on aquatic ecosystems integrity are introduced.

  • 49. McConville, Jennifer
    et al.
    Kain, Jaan-Henrik
    Kvarnström, Elisabeth
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630), Environmental Geochemistry and Ecotechnology.
    Bridging sanitation engineering and planning: theory and practice in Burkina Faso2011In: Journal of Water Sanitation and Hygiene for Development, ISSN 2043-9083, Vol. 1, no 3, p. 205-212Article in journal (Refereed)
    Abstract [en]

    The global challenge of providing sanitation services to the un-served underlines a need to change the way in which sanitation planning and service provision is approached. This paper offers a framework for categorizing sanitation projects planning processes based on planning steps and procedural planning theory to help engineers and sanitation planners gain a deeper understanding of the dynamics of these processes. The analysis identifies and discusses trends in both guidelines and actual sanitation programs. The results show that contemporary sanitation planning guidelines and field projects utilize patchwork processes of different planning modes, although the step of designing options is dominated by an expert-driven, rational-comprehensive approach. The use of planning theory can help engineers to ask critical questions about the objectives of the planning process and to develop context-appropriate planning processes that will make a difference for improving sanitation service provision.

  • 50.
    McGivney, Eric
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Carnegie Mellon University, United States.
    Carlsson, Magnus
    Gustafsson, Jon Petter
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. Swedish University of Agricultural Sciences, Sweden.
    Gorokhova, Elena
    Effects of UV-C and Vacuum-UV TiO2 Advanced Oxidation Processes on the Acute Mortality of Microalgae2015In: Photochemistry and Photobiology, ISSN 0031-8655, E-ISSN 1751-1097, Vol. 91, no 5, p. 1142-1149Article in journal (Refereed)
    Abstract [en]

    Advanced oxidation processes/technologies (AOT) that combine a semiconductor, such as titanium dioxide (TiO2), with a UV source have been used to eliminate microorganisms in various water treatment applications. To facilitate the applicability of this technique, the gain in efficiency from the semiconductor compared to the UV source alone with respect to different target organisms requires evaluation. The primary objective of this study was to determine the effects of TiO2 and UV wavelength on a freshwater alga, Pseudokirchneriella subcapitata and a marine alga, Tetraselmis suecica. For each species, dose-response experiments were conducted to determine the median lethal dose (LC50) of the following treatments: UV light emitted with a peak of 254nm, UV light emitted with a peak of 254nm in the presence of TiO2 and UV light emitted with a peak of 254 and 185nm in the presence of TiO2. In both species, the presence of TiO2 significantly increased mortality. Across all three treatments, P.subcapitata was more sensitive than T.suecica; moreover, the addition of the 185nm wavelength significantly increased cell mortality in P.subcapitata but not in T.suecica.

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