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I had completed my master degree in Botany from University of Kalyani, India. Now I am pursuing my PhD at the final stage from the same University where as my thesis is related to water disinfection.
A large variety of Advanced Oxidation Processes (AOPs) to degrade trace organic compounds during water treatment have been studied on a lab scale in the past. This paper presents the combination of inline electrolytic chlorine generation (ECl2) with low pressure UV reactors (UV/ECl2) in order to allow the operation of a chlorine-based AOP without the need for any chlorine dosing. Lab studies showed that from a Free Available Chlorine (FAC) concentration range between 1 and 18 mg/L produced by ECl2 up to 84% can be photolyzed to form, among others, hydroxyl radicals (OH) with an UV energy input of 0.48 kWh/m3. This ratio could be increased to 97% by doubling the UV energy input to 0.96 kWh/m3 and was constant throughout the tested FAC range. Also the achieved radical yield of 64% did not change along the given FAC concentration range and no dependence between pH 6 and pH 8 could be found, largely simplifying the operation of a pilot scale system in drinking water treatment. Whereas with ECl2 alone only 5% of benzotriazoles could be degraded, the combination with UV improved the degradation to 89%. Similar results were achieved for 4-methylbenzotriazole, 5-methylbenzotriazole and iomeprol. Oxipurinol and gabapentin were readily degraded by ECl2 alone. The trihalomethanes values were maintained below the Germany drinking water standard of 50 µg/L, provided residual chlorine concentrations are kept within the permissible limits. The here presented treatment approach is promising for decentralized treatment application but requires further optimization in order to reduce its energy requirements.
Philipp Otter; Katharina Mette; Robert Wesch; Tobias Gerhardt; Frank-Marc Krüger; Alexander Goldmaier; Florian Benz; Pradyut Malakar; Thomas Grischek. Oxidation of Selected Trace Organic Compounds through the Combination of Inline Electro-Chlorination with UV Radiation (UV/ECl2) as Alternative AOP for Decentralized Drinking Water Treatment. Water 2020, 12, 3275 .
AMA StylePhilipp Otter, Katharina Mette, Robert Wesch, Tobias Gerhardt, Frank-Marc Krüger, Alexander Goldmaier, Florian Benz, Pradyut Malakar, Thomas Grischek. Oxidation of Selected Trace Organic Compounds through the Combination of Inline Electro-Chlorination with UV Radiation (UV/ECl2) as Alternative AOP for Decentralized Drinking Water Treatment. Water. 2020; 12 (11):3275.
Chicago/Turabian StylePhilipp Otter; Katharina Mette; Robert Wesch; Tobias Gerhardt; Frank-Marc Krüger; Alexander Goldmaier; Florian Benz; Pradyut Malakar; Thomas Grischek. 2020. "Oxidation of Selected Trace Organic Compounds through the Combination of Inline Electro-Chlorination with UV Radiation (UV/ECl2) as Alternative AOP for Decentralized Drinking Water Treatment." Water 12, no. 11: 3275.
Reliable data on the economic feasibility of small-scale rural water supply systems are insufficient, which hampers the allocation of funds to construct them, even as the need for their construction increases. To address this gap, three newly constructed water supply systems with water points in Nepal, Egypt, and Tanzania were accompanied by the authors throughout the planning and implementation phases and up to several years of operation. This study presents an analysis of their economic feasibility and suggests important factors for successful water supply system implementation at other rural locations. The initial investment for construction of the new water supply systems ranged from 23,600 € to 44,000 €, and operation and maintenance costs ranged from 547 € to 1,921 € per year. The water price and actual multi-year average quantity of tapped water at each site were 7.7 €/m³ & 0.67 m³/d in Nepal, 0.7 €/m³ & 0.88 m³/d in Egypt and 0.9 €/m³ & 8.65 m³/d in Tanzania. Although the new water supply systems enjoyed acceptance among the consumers, the actual average water quantity tapped ranged from just 17 to 30 % of the demand for which the new supply systems were designed. While two of three sites successfully yielded a cash surplus through the sale of water, sufficient for operation, maintenance and basic repairs, no site showed a realistic chance of recovering the initial investment (reaching the break-even point) within the projected lifetime of the technical infrastructure. Reaching the break-even point within 5 years, which would be necessary to attract private investors, would require an unrealistic increase of the water price or the water consumption by factors ranging from 5.2 to 9.0. The economic viability of such systems therefore depends strongly on the quantity of water consumed and the water price, as well as the availability of funding from governments, NGOs or other sponsors not primarily interested in a financial return on their investment.
Philipp Otter; Wolfgang Sattler; Thomas Grischek; Martina Jaskolski; Emanuel Mey; Nico Ulmer; Peter Grossmann; Fabien Matthias; Pradyut Malakar; Alexander Goldmaier; Florian Benz; Calvin Ndumwa. Economic evaluation of water supply systems operated with solar-driven electro-chlorination in rural regions in Nepal, Egypt and Tanzania. Water Research 2020, 187, 116384 .
AMA StylePhilipp Otter, Wolfgang Sattler, Thomas Grischek, Martina Jaskolski, Emanuel Mey, Nico Ulmer, Peter Grossmann, Fabien Matthias, Pradyut Malakar, Alexander Goldmaier, Florian Benz, Calvin Ndumwa. Economic evaluation of water supply systems operated with solar-driven electro-chlorination in rural regions in Nepal, Egypt and Tanzania. Water Research. 2020; 187 ():116384.
Chicago/Turabian StylePhilipp Otter; Wolfgang Sattler; Thomas Grischek; Martina Jaskolski; Emanuel Mey; Nico Ulmer; Peter Grossmann; Fabien Matthias; Pradyut Malakar; Alexander Goldmaier; Florian Benz; Calvin Ndumwa. 2020. "Economic evaluation of water supply systems operated with solar-driven electro-chlorination in rural regions in Nepal, Egypt and Tanzania." Water Research 187, no. : 116384.
The supply of safe drinking water in rural developing areas is still a matter of concern, especially if surface water, shallow wells, and wells with non-watertight headworks are sources for drinking water. Continuously changing raw water conditions, flood and extreme rainfall events, anthropogenic pollution, and lacking electricity supply in developing regions require new and adapted solutions to treat and render water safe for distribution. This paper presents the findings of a pilot test conducted in Uttarakhand, India, where a river bank filtration (RBF) well was combined with a solar-driven and online-monitored electro-chlorination system, treating fecal-contaminated Ganga River water. While the RBF well provided nearly turbidity- and pathogen-free water as well as buffered fluctuations in source water qualities, the electro-chlorination system provided disinfection based on the inline conversion of chloride to hypochlorous acid. The conducted sampling campaigns provided complete disinfection (>6.7 log) and the adequate supply of residual disinfectant (0.27 ± 0.17 mg/L). The system could be further optimized to local conditions and allows the supply of microbial-safe water for river bound communities, even during monsoon periods and under the low natural chloride regimes typical for this region.
Philipp Otter; Pradyut Malakar; Cornelius Sandhu; Thomas Grischek; Sudhir Kumar Sharma; Prakash Chandra Kimothi; Gabriele Nüske; Martin Wagner; Alexander Goldmaier; Florian Benz. Combination of River Bank Filtration and Solar-driven Electro-Chlorination Assuring Safe Drinking Water Supply for River Bound Communities in India. Water 2019, 11, 122 .
AMA StylePhilipp Otter, Pradyut Malakar, Cornelius Sandhu, Thomas Grischek, Sudhir Kumar Sharma, Prakash Chandra Kimothi, Gabriele Nüske, Martin Wagner, Alexander Goldmaier, Florian Benz. Combination of River Bank Filtration and Solar-driven Electro-Chlorination Assuring Safe Drinking Water Supply for River Bound Communities in India. Water. 2019; 11 (1):122.
Chicago/Turabian StylePhilipp Otter; Pradyut Malakar; Cornelius Sandhu; Thomas Grischek; Sudhir Kumar Sharma; Prakash Chandra Kimothi; Gabriele Nüske; Martin Wagner; Alexander Goldmaier; Florian Benz. 2019. "Combination of River Bank Filtration and Solar-driven Electro-Chlorination Assuring Safe Drinking Water Supply for River Bound Communities in India." Water 11, no. 1: 122.
Arsenic contamination in drinking water resources is of major concern in the Ganga delta plains of West Bengal in India and Bangladesh. Here, several laboratory and field studies on arsenic removal from drinking water resources were conducted in the past and the application of strong-oxidant-induced co-precipitation of arsenic on iron hydroxides is still considered as the most promising mechanism. This paper suggests an autonomous, solar driven arsenic removal setting and presents the findings of a long term field test conducted in West Bengal. The system applies an inline-electrolytic cell for in situ chlorine production using the natural chloride content of the water and by that substituting the external dosing of strong oxidants. Co-precipitation of As(V) occurs on freshly formed iron hydroxide, which is removed by Manganese Greensand Plus® filtration. The test was conducted for ten months under changing source water conditions considering arsenic (187 ± 45 µg/L), iron (5.5 ± 0.8 mg/L), manganese (1.5 ± 0.4 mg/L), phosphate (2.4 ± 1.3 mg/L) and ammonium (1.4 ± 0.5 mg/L) concentrations. Depending on the system setting removal rates of 94% for arsenic (10 ± 4 µg/L), >99% for iron (0.03 ± 0.03 mg/L), 96% for manganese (0.06 ± 0.05 mg/L), 72% for phosphate (0.7 ± 0.3 mg/L) and 84% for ammonium (0.18 ± 0.12 mg/L) were achieved—without the addition of any chemicals/adsorbents. Loading densities of arsenic on iron hydroxides averaged to 31 µgAs/mgFe. As the test was performed under field conditions and the here proposed removal mechanisms work fully autonomously, it poses a technically feasible treatment alternative, especially for rural areas.
Philipp Otter; Pradyut Malakar; Bana Bihari Jana; Thomas Grischek; Florian Benz; Alexander Goldmaier; Ulrike Feistel; Joydev Jana; Susmita Lahiri; Juan Antonio Alvarez. Arsenic Removal from Groundwater by Solar Driven Inline-Electrolytic Induced Co-Precipitation and Filtration—A Long Term Field Test Conducted in West Bengal. International Journal of Environmental Research and Public Health 2017, 14, 1167 .
AMA StylePhilipp Otter, Pradyut Malakar, Bana Bihari Jana, Thomas Grischek, Florian Benz, Alexander Goldmaier, Ulrike Feistel, Joydev Jana, Susmita Lahiri, Juan Antonio Alvarez. Arsenic Removal from Groundwater by Solar Driven Inline-Electrolytic Induced Co-Precipitation and Filtration—A Long Term Field Test Conducted in West Bengal. International Journal of Environmental Research and Public Health. 2017; 14 (10):1167.
Chicago/Turabian StylePhilipp Otter; Pradyut Malakar; Bana Bihari Jana; Thomas Grischek; Florian Benz; Alexander Goldmaier; Ulrike Feistel; Joydev Jana; Susmita Lahiri; Juan Antonio Alvarez. 2017. "Arsenic Removal from Groundwater by Solar Driven Inline-Electrolytic Induced Co-Precipitation and Filtration—A Long Term Field Test Conducted in West Bengal." International Journal of Environmental Research and Public Health 14, no. 10: 1167.