The Experts below are selected from a list of 10386 Experts worldwide ranked by ideXlab platform
Shaoqi Zhou - One of the best experts on this subject based on the ideXlab platform.
-
transformation of pollutants in landfill leachate treated by a combined sequence batch reactor coagulation fenton oxidation and biological aerated filter technology
Process Safety and Environmental Protection, 2011Co-Authors: Shaoqi Zhou, Dongyu Chen, Ke Zheng, Fanghui QinAbstract:A combination process was developed including sequence batch reactor (SBR), coagulation, Fenton oxidation, and biological aerated filtering (BAF) in series for the purpose of removing pollutants in landfill leachate. The high contents of dissolved organic matters (DOM) of landfill leachate in each treatment process were fractionated into humic acid (HA), fulvic acid (FA), and hydrophilic (HyI) fractions. The composition changes and characteristics of DOM were investigated. Subsequently, seventy organic micropollutants in raw leachate were detected, and twenty-five organic pollutants were completely removed by SBR process. Low organic pollutants and high turbidity removals were achieved by coagulation. Thirty-seven organic micropollutants disappeared completely in Fenton Effluent and low molecular weight fractions were removed by BAF preferentially. A total reduction of COD (98.4%), BOD5 (99.1%), NH4-N (99.3%), TP (99.3%), SS (91.8%), turbidity (99.2%) and color (99.6%) achieved in the final BAF Effluent indicated the effectiveness of the combined plant. Moreover, metal ions of Cu, Ni, Zn, Mn, Cr, Mg, Pb, Cd, Al, Fe and anions of SO42−, Cl−, NO3−, NO2−, and PO43− in raw leachate and four treated Effluents were measured, respectively. The observations indicated that leachate treated by the combined process still contained higher concentration of total heavy metals and inorganic anions than the surrounding water environment, though no violation to Effluent Standard was found. The possible risk in leachate should not be negligible because landfill leachate was still one of the major sources of heavy metals and inorganic pollutants discharged to the surrounding environment.
-
the biological treatment of landfill leachate using a simultaneous aerobic and anaerobic saa bio reactor system
Chemosphere, 2008Co-Authors: Zhiquan Yang, Shaoqi ZhouAbstract:A set of simultaneous aerobic and anaerobic (SAA) bio-reactor system was used for the removal of organic pollutants and ammonia in the landfill leachate generated from Datian Shan Landfill in Guangzhou, China. The influent concentrations of COD and NH(4)(+)-N were 1000-3300 and 80-230 mg L(-1), respectively. The average Effluent concentrations of COD and NH(4)(+)-N were 131 and 7 mg L(-1), respectively. The concentrations of COD and NH(4)(+)-N had reached the Chinese second grade Effluent Standard (COD<300 mg L(-1), NH(4)(+)-N<25 mg L(-1)) for this kind of wastewater. Gas chromatogram-mass spectrum (GC/MS) analysis was used to measure the organic pollutants in the landfill leachate. About 87 organics were detected in this landfill leachate, and 16 of them belong to the list of environmental priority pollutants established by the US Environmental Protection Agency. About 31 of the 87 organic pollutants were completely removed by the SAA bio-reactor, the concentrations of further 14 organic pollutants were reduced by more than 80%, and the removal efficiencies of the other 25 organic pollutants were over 50%.
Ming Hung Wong - One of the best experts on this subject based on the ideXlab platform.
-
nitrogen and phosphate mass balance in a sub surface flow constructed wetland for treating municipal wastewater
Ecological Engineering, 2008Co-Authors: A K C Chung, N F Y Tam, Ming Hung WongAbstract:Abstract This paper reports on the feasibility of using sub-surface horizontal flow constructed wetlands to treat municipal wastewater in Hong Kong. Two different hydraulic retention times (10-day and 5-day) and different types of treatments (with and without vegetation) were investigated. Better performance in the planted treatments was obtained in both hydraulic retention time treatments. Nutrients were better removed in treatments with plants (DOC 68% and 72%; NH4-N 92% and 95%; TKN 65% and 62%; PO4-P 79% and 72%; TP 67% and 52% for 10-day HRT; 5-day HRT treatments). In the unplanted treatments, negative values were achieved in the removal of phosphate in wastewater and the presence of plants could further polish the wastewater so phosphate concentrations decreased in the planted treatments. The Effluent concentrations in the planted treatments meet the Inland Water A Effluent Standard, and they can be used in recreation park in Hong Kong (1 mg L−1 of NOx; 15 mg L−1 of NH3; 1 mg L−1 of TP).
Yuyang Long - One of the best experts on this subject based on the ideXlab platform.
-
characterization of solidification for disposal of hazardous waste landfill leachate
Environmental Science and Pollution Research, 2020Co-Authors: Lijia Wang, Dongsheng Shen, Jinmu Ruan, Yuyang LongAbstract:Hazardous waste landfill leachate (HWLL) with high concentrations of salt and pollutants has created a bottleneck at hazardous waste landfills. This study applied a cement-based curing method to the disposal of HWLL. The highest contaminant fixing rate was achieved by adjusting the composition and proportion of the curing base, the content of additives, and the liquid-solid (L/S) ratio of the leachate to the curing base. The fixing rates for chemical oxygen demand and salt content in HWLL reached the highest values of 95.1% and 86.1%, respectively, when the Portland cement to metakaolin ratio was 3:2; the L/S was 1; and diatomite and activated carbon were added at 0.5% and 0.25%, respectively. The addition of glass fiber to the curing base improved the crack resistance of the solidified product. A simulated landfill experiment further indicated that after 116 days of leaching, the leachate Effluent pollutant concentrations of the landfill column were lower than the Effluent Standard. Solidification is a feasible method for HWLL disposal.
M. Khazaei - One of the best experts on this subject based on the ideXlab platform.
-
Qom Wastewater Disinfection with Hydrogen Peroxide-Silver Ion Complex
Qom University of Medical Sciences, 2012Co-Authors: M. KhazaeiAbstract:<p><strong>Background and objectives</strong></p><p>Hydrogen peroxide solution with stabilized formulation with oligodynamic amounts of silver ion (trade mark: Nanosil) recently became a popular disinfectant for fruits, vegetables, surfaces, medical instruments and so on.</p><p> </p><p><strong>Methods</strong></p><p>This study was based on determining efficiency of hydrogen peroxide-silver ion complex in six different concentrations measured through removal of total coli forms from samples taken from Qom wastewater. All six different concentrations of disinfectant were incubated separately with wastewater for one hour. Sample size was 12 and sampling was done weekly.</p><p> </p><p><strong>Results</strong></p><p>In the concentration of 80 and 480 mg/l, logarithmic removal value of total coli forms was 1.9 and 4.5 respectively. In CT value 8600(mg/l).min and more, the total coli forms Effluent Standard for surface water discharge and agriculture irrigation was achieved (Iranian environmental protection agency act).</p><p> </p><p><strong>Conclusion</strong></p>Use of hydrogen peroxide-silver ion complex as a water and wastewater disinfectant, has some benefits such as elimination of hazardous by products, measurable residual amount and so on. However its application in wastewater Effluent is more costly than other usual disinfectants so it is not economically advisabl
-
Qom Wastewater Disinfection with Hydrogen Peroxide-Silver Ion Complex
Qom University of Medical Sciences, 2008Co-Authors: M. Khazaei, R. Nabizadeh, K. Naddafi, M. Roshany, B. FarzinniaAbstract:Background and objectivesHydrogen peroxide solution with stabilized formulation with oligodynamic amounts of silver ion (trade mark: Nanosil) recently became a popular disinfectant for fruits, vegetables, surfaces, medical instruments and so on.MethodsThis study was based on determining efficiency of hydrogen peroxide-silver ion complex in six different concentrations measured through removal of total coli forms from samples taken from Qom wastewater. All six different concentrations of disinfectant were incubated separately with wastewater for one hour. Sample size was 12 and sampling was done weekly. ResultsIn the concentration of 80 and 480 mg/l, logarithmic removal value of total coli forms was 1.9 and 4.5 respectively. In CT value 8600(mg/l).min and more, the total coli forms Effluent Standard for surface water discharge and agriculture irrigation was achieved (Iranian environmental protection agency act).ConclusionUse of hydrogen peroxide-silver ion complex as a water and wastewater disinfectant, has some benefits such as elimination of hazardous by products, measurable residual amount and so on. However its application in wastewater Effluent is more costly than other usual disinfectants so it is not economically advisable. Keywords: Disinfection; Wastewater; Hydrogen peroxide; Silver Ion
Tsugufumi Matsuyama - One of the best experts on this subject based on the ideXlab platform.
-
Development of Methods to Evaluate Several Levels of Uranium Concentrations in Drainage Water Using Total Reflection X-Ray Fluorescence Technique
Frontiers Media S.A., 2019Co-Authors: Tsugufumi Matsuyama, Yukie Izumoto, Kota Ishii, Yasuhiro Sakai, Hiroshi YoshiiAbstract:As a country's law stipulates the Effluent Standard uranium concentration in drainage water, the uranium concentration must be determined when drainage water is released from a uranium handling facility, such as the Fukushima Daiichi nuclear power plant. The maximum allowable limit for uranium release at each facility is defined taking into consideration the situation of the facility, such as 1/10 to 1/100 of this Effluent Standard value. Currently, the uranium concentration of drainage water is commonly determined by α-particle spectrometry, in which several liters of drainage water must be evaporated, requiring about half of a day followed by 2–3 h of measurements, due to the low specific radioactivity of uranium. This work proposes a new methodology for the rapid and simple measurement of several levels of uranium in drainage water by a total reflection X-ray fluorescence (TXRF) analysis. Using a portable device for TXRF measurements was found to enable measurements with 1/10 the sensitivity of the Effluent Standard value by 10 times condensation of the uranium-containing sample solution; a benchtop device is useful to measure uranium concentrations <1/100 of the Effluent Standard value. Therefore, the selective usage of methods by a portable and benchtop devices allows for screening and precise evaluation of uranium concentrations in drainage water
