The Experts below are selected from a list of 62157 Experts worldwide ranked by ideXlab platform
Gatze Lettinga - One of the best experts on this subject based on the ideXlab platform.
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anaerobic Sewage Treatment in a one stage uasb reactor and a combined uasb digester system
Water Research, 2004Co-Authors: Nidal Mahmoud, Huub J. Gijzen, G Zeeman, Gatze LettingaAbstract:The Treatment of Sewage at 15°C was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-Digester system. The latter consists of a UASB reactor complemented with a digester for mutual Sewage Treatment and sludge stabilisation. The UASB reactor was operated at a hydraulic retention time of 6 h and a controlled temperature of 15°C, the average Sewage temperature during wintertime of some Middle East countries. The digester was operated at 35°C. The UASB-Digester system provided significantly (significance level 5%) higher COD removal efficiencies than the one-stage UASB reactor. The achieved removal efficiencies in the UASB-Digester system and the one-stage UASB reactor for total, suspended, colloidal and dissolved COD were 66%, 87%, 44% and 30%, and 44%, 73%, 3% and 5% for both systems, respectively. The stability values of the wasted sludge from the one-stage UASB reactor and the UASB-Digester system were, respectively, 0.47 and 0.36 g CH4-COD/g COD. Therefore, the anaerobic Sewage Treatment at low temperature in a UASB-Digester system is promising
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Anaerobic Sewage Treatment in a one-stage UASB reactor and a combined UASB-Digester system.
Water research, 2004Co-Authors: Nidal Mahmoud, Huub J. Gijzen, G Zeeman, Gatze LettingaAbstract:The Treatment of Sewage at 15 degrees C was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-Digester system. The latter consists of a UASB reactor complemented with a digester for mutual Sewage Treatment and sludge stabilisation. The UASB reactor was operated at a hydraulic retention time of 6h and a controlled temperature of 15 degrees C, the average Sewage temperature during wintertime of some Middle East countries. The digester was operated at 35 degrees C. The UASB-Digester system provided significantly (significance level 5%) higher COD removal efficiencies than the one-stage UASB reactor. The achieved removal efficiencies in the UASB-Digester system and the one-stage UASB reactor for total, suspended, colloidal and dissolved COD were 66%, 87%, 44% and 30%, and 44%, 73%, 3% and 5% for both systems, respectively. The stability values of the wasted sludge from the one-stage UASB reactor and the UASB-Digester system were, respectively, 0.47 and 0.36g CH(4)-COD/g COD. Therefore, the anaerobic Sewage Treatment at low temperature in a UASB-Digester system is promising.
Chunxia Wang - One of the best experts on this subject based on the ideXlab platform.
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monitoring priority pollutants in a Sewage Treatment process by dichloromethane extraction and triolein semipermeable membrane device spmd
Chemosphere, 2001Co-Authors: Yi Wang, Zijian Wang, Chunxia WangAbstract:Semipermeable membrane devices containing a neutral lipid triolein (triolein-SPMD) and conventional dichloromethane extraction were used to monitor the presence and concentrations of priority organic pollutants in a Sewage Treatment process in Beijing, China. Both samples gave similar information on the presence of target PCB congeners, PAHs, Organochlorine pesticides and substituted benzenes in Sewage at all sites. After 20 days' sampling, the concentrations of contaminants in triolein of SPMD were much higher than those in dichloromethane extracts, which resulted in easier analysis, improved the detection limits, and increased the accuracy. Previous field mean sampling rates for SPMD were used to estimate concentrations of PCB congeners in Sewage, which compared to their determined concentrations by dichloromethane extraction. The consistency and superiority of SPMD technology were proved for the detection of priority organic contaminants from Sewage. Lower removal rates for PCB congeners and PAHs coincided with the persistence of them in environment. More attention should be paid to urban Sewage Treatment process adopting activated-sludge method, where priority organic pollutants might not be removed, even present higher concentrations after Treatment. (C) 2001 Elsevier Science Ltd. All rights reserved.
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monitoring priority pollutants in a Sewage Treatment process by dichloromethane extraction and triolein semipermeable membrane device spmd
Chemosphere, 2001Co-Authors: Yi Wang, Zijian Wang, Chunxia WangAbstract:Abstract Semipermeable membrane devices containing a neutral lipid triolein (triolein-SPMD) and conventional dichloromethane extraction were used to monitor the presence and concentrations of priority organic pollutants in a Sewage Treatment process in Beijing, China. Both samples gave similar information on the presence of target PCB congeners, PAHs, Organochlorine pesticides and substituted benzenes in Sewage at all sites. After 20 days’ sampling, the concentrations of contaminants in triolein of SPMD were much higher than those in dichloromethane extracts, which resulted in easier analysis, improved the detection limits, and increased the accuracy. Previous field mean sampling rates for SPMD were used to estimate concentrations of PCB congeners in Sewage, which compared to their determined concentrations by dichloromethane extraction. The consistency and superiority of SPMD technology were proved for the detection of priority organic contaminants from Sewage. Lower removal rates for PCB congeners and PAHs coincided with the persistence of them in environment. More attention should be paid to urban Sewage Treatment process adopting activated-sludge method, where priority organic pollutants might not be removed, even present higher concentrations after Treatment.
G Zeeman - One of the best experts on this subject based on the ideXlab platform.
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enrichment of denitrifying methanotrophic bacteria for application after direct low temperature anaerobic Sewage Treatment
Journal of Hazardous Materials, 2012Co-Authors: Christel Kampman, G Zeeman, Tim L G Hendrickx, Francisca A Luesken, Theo A Van Alen, Huub Op Den J M Camp, Mike S M Jetten, Cees J N Buisman, H TemminkAbstract:Abstract Despite many advantages of anaerobic Sewage Treatment over conventional activated sludge Treatment, it has not yet been applied in temperate zones. This is especially because effluent from low-temperature anaerobic Treatment contains nitrogen and dissolved methane. The presence of nitrogen and methane offers the opportunity to develop a reactor in which methane is used as electron donor for denitrification. Such a reactor could be used in a new concept for low-temperature anaerobic Sewage Treatment, consisting of a UASB-digester system, a reactor for denitrification coupled to anaerobic methane oxidation, and a nitritation reactor. In the present study denitrifying methanotrophic bacteria similar to ‘ Candidatus Methylomirabilis oxyfera’ were enriched. Maximum volumetric nitrite consumption rates were 33.5 mg NO 2 − -N/L d (using synthetic medium) and 37.8 mg NO 2 − -N/L d (using medium containing effluent from a Sewage Treatment plant), which are similar to the maximum rate reported so far. Though the goal was to increase the rates, in both reactors, after reaching these maximum rates, volumetric nitrite consumption rates decreased in time. Results indicate biomass washout may have significantly decelerated enrichment. Therefore, to obtain higher volumetric consumption rates, further research should focus on systems with complete biomass retention.
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adapting uasb technology for Sewage Treatment in palestine and jordan
Water Science and Technology, 2008Co-Authors: Nidal Mahmoud, G Zeeman, Jules B Van LierAbstract:High rate anaerobic technologies offer cost-effective solutions for “Sewage” Treatment in the temperate climate of Palestine and Jordan. However, local Sewage characteristics demand amendments to the conventional UASB reactor design. A solution is found in a parallel operating digester unit that stabilises incoming solids and enriches the UASB sludge bed with methanogenic activity. The digester operational conditions were assessed by operating eight CSTRs fed with primary sludge. The results showed a high degree of sludge stabilization in the parallel digesters at SRTs≥10 and 15 days at process temperatures of 35 and 25°C, respectively. The technical feasibility of the UASB-digester combination was demonstrated by continuous flow pilot-scale experiments. A pilot UASB reactor was operated for 81 days at 6 hours HRT and 15°C and was fed with raw domestic Sewage. This period was subsequently followed by an 83 day operation period incorporating a parallel digester unit, which was operated at 35°C. The UASB-digester combination achieved removal efficiencies of total, suspended, colloidal and dissolved CODs of respectively 66, 87, 44 and 30%. Preliminary model calculations indicated that a total reactor volume of the UASB-digester system corresponding to 8.6 hours HRT might suffice for Sewage Treatment in Palestine.
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anaerobic Sewage Treatment
Water Encyclopedia, 2005Co-Authors: Lucas Seghezzo, G Zeeman, G LettingaAbstract:The state-of-the art of the anaerobic Treatment of Sewage, or domestic wastewater, is presented. The chapter begins with a brief definition of Sewage and a description of the main pollutants contained in it. Negative consequences of the uncontrolled discharge of raw or badly treated Sewage into the environment are summarized, with emphasis on health aspects. The technologies available to treat Sewage are presented, focusing on the upflow anaerobic sludge bed (UASB) reactor. Some examples of the use of UASB reactors for Sewage Treatment are discussed. The chapter ends with an indication of the potential of UASB reactors to contribute to the achievement of more sustainable sanitation in developing countries. Keywords: Sewage; domestic wastewater; anaerobic Treatment; anaerobic digestion; UASB reactors; decentralized sanitation
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anaerobic Sewage Treatment in a one stage uasb reactor and a combined uasb digester system
Water Research, 2004Co-Authors: Nidal Mahmoud, Huub J. Gijzen, G Zeeman, Gatze LettingaAbstract:The Treatment of Sewage at 15°C was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-Digester system. The latter consists of a UASB reactor complemented with a digester for mutual Sewage Treatment and sludge stabilisation. The UASB reactor was operated at a hydraulic retention time of 6 h and a controlled temperature of 15°C, the average Sewage temperature during wintertime of some Middle East countries. The digester was operated at 35°C. The UASB-Digester system provided significantly (significance level 5%) higher COD removal efficiencies than the one-stage UASB reactor. The achieved removal efficiencies in the UASB-Digester system and the one-stage UASB reactor for total, suspended, colloidal and dissolved COD were 66%, 87%, 44% and 30%, and 44%, 73%, 3% and 5% for both systems, respectively. The stability values of the wasted sludge from the one-stage UASB reactor and the UASB-Digester system were, respectively, 0.47 and 0.36 g CH4-COD/g COD. Therefore, the anaerobic Sewage Treatment at low temperature in a UASB-Digester system is promising
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Anaerobic Sewage Treatment in a one-stage UASB reactor and a combined UASB-Digester system.
Water research, 2004Co-Authors: Nidal Mahmoud, Huub J. Gijzen, G Zeeman, Gatze LettingaAbstract:The Treatment of Sewage at 15 degrees C was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-Digester system. The latter consists of a UASB reactor complemented with a digester for mutual Sewage Treatment and sludge stabilisation. The UASB reactor was operated at a hydraulic retention time of 6h and a controlled temperature of 15 degrees C, the average Sewage temperature during wintertime of some Middle East countries. The digester was operated at 35 degrees C. The UASB-Digester system provided significantly (significance level 5%) higher COD removal efficiencies than the one-stage UASB reactor. The achieved removal efficiencies in the UASB-Digester system and the one-stage UASB reactor for total, suspended, colloidal and dissolved COD were 66%, 87%, 44% and 30%, and 44%, 73%, 3% and 5% for both systems, respectively. The stability values of the wasted sludge from the one-stage UASB reactor and the UASB-Digester system were, respectively, 0.47 and 0.36g CH(4)-COD/g COD. Therefore, the anaerobic Sewage Treatment at low temperature in a UASB-Digester system is promising.
Nidal Mahmoud - One of the best experts on this subject based on the ideXlab platform.
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adapting uasb technology for Sewage Treatment in palestine and jordan
Water Science and Technology, 2008Co-Authors: Nidal Mahmoud, G Zeeman, Jules B Van LierAbstract:High rate anaerobic technologies offer cost-effective solutions for “Sewage” Treatment in the temperate climate of Palestine and Jordan. However, local Sewage characteristics demand amendments to the conventional UASB reactor design. A solution is found in a parallel operating digester unit that stabilises incoming solids and enriches the UASB sludge bed with methanogenic activity. The digester operational conditions were assessed by operating eight CSTRs fed with primary sludge. The results showed a high degree of sludge stabilization in the parallel digesters at SRTs≥10 and 15 days at process temperatures of 35 and 25°C, respectively. The technical feasibility of the UASB-digester combination was demonstrated by continuous flow pilot-scale experiments. A pilot UASB reactor was operated for 81 days at 6 hours HRT and 15°C and was fed with raw domestic Sewage. This period was subsequently followed by an 83 day operation period incorporating a parallel digester unit, which was operated at 35°C. The UASB-digester combination achieved removal efficiencies of total, suspended, colloidal and dissolved CODs of respectively 66, 87, 44 and 30%. Preliminary model calculations indicated that a total reactor volume of the UASB-digester system corresponding to 8.6 hours HRT might suffice for Sewage Treatment in Palestine.
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anaerobic Sewage Treatment in a one stage uasb reactor and a combined uasb digester system
Water Research, 2004Co-Authors: Nidal Mahmoud, Huub J. Gijzen, G Zeeman, Gatze LettingaAbstract:The Treatment of Sewage at 15°C was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-Digester system. The latter consists of a UASB reactor complemented with a digester for mutual Sewage Treatment and sludge stabilisation. The UASB reactor was operated at a hydraulic retention time of 6 h and a controlled temperature of 15°C, the average Sewage temperature during wintertime of some Middle East countries. The digester was operated at 35°C. The UASB-Digester system provided significantly (significance level 5%) higher COD removal efficiencies than the one-stage UASB reactor. The achieved removal efficiencies in the UASB-Digester system and the one-stage UASB reactor for total, suspended, colloidal and dissolved COD were 66%, 87%, 44% and 30%, and 44%, 73%, 3% and 5% for both systems, respectively. The stability values of the wasted sludge from the one-stage UASB reactor and the UASB-Digester system were, respectively, 0.47 and 0.36 g CH4-COD/g COD. Therefore, the anaerobic Sewage Treatment at low temperature in a UASB-Digester system is promising
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Anaerobic Sewage Treatment in a one-stage UASB reactor and a combined UASB-Digester system.
Water research, 2004Co-Authors: Nidal Mahmoud, Huub J. Gijzen, G Zeeman, Gatze LettingaAbstract:The Treatment of Sewage at 15 degrees C was investigated in a one-stage upflow anaerobic sludge blanket (UASB) reactor and a UASB-Digester system. The latter consists of a UASB reactor complemented with a digester for mutual Sewage Treatment and sludge stabilisation. The UASB reactor was operated at a hydraulic retention time of 6h and a controlled temperature of 15 degrees C, the average Sewage temperature during wintertime of some Middle East countries. The digester was operated at 35 degrees C. The UASB-Digester system provided significantly (significance level 5%) higher COD removal efficiencies than the one-stage UASB reactor. The achieved removal efficiencies in the UASB-Digester system and the one-stage UASB reactor for total, suspended, colloidal and dissolved COD were 66%, 87%, 44% and 30%, and 44%, 73%, 3% and 5% for both systems, respectively. The stability values of the wasted sludge from the one-stage UASB reactor and the UASB-Digester system were, respectively, 0.47 and 0.36g CH(4)-COD/g COD. Therefore, the anaerobic Sewage Treatment at low temperature in a UASB-Digester system is promising.
Jingfu Liu - One of the best experts on this subject based on the ideXlab platform.
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understanding the distribution degradation and fate of organophosphate esters in an advanced municipal Sewage Treatment plant based on mass flow and mass balance analysis
Science of The Total Environment, 2016Co-Authors: Kang Liang, Jingfu LiuAbstract:Although organophosphate esters (OPEs) in the ambient environment are from Sewage Treatment plants due to the discharge of effluent and application of sludge, the distribution, degradation and fate of OPEs in advanced municipal Sewage Treatment plants remain unclear. This work focused on the use of mass flow and mass balance analysis to understand the behaviors and fate of 14 OPEs in an advanced municipal Sewage Treatment plant. OPEs were detected in all Sewage water and sludge samples with total OPEs (ΣOPEs) concentrations of 1399 ± 263 ng/L in raw Sewage aqueous phase, 833 ± 175 ng/L in tertiary effluent aqueous phase, and 315 ± 89 ng/g dry weight in dewatered sludge. The dissolved concentrations of ΣOPEs significantly decreased during biological Treatment, whereas negligible decrease was observed in mechanical and physical-chemical Treatments. For individual OPE, the chlorinated tris(2-chloroethyl) phosphate (TCEP) and tris(2-chloroisopropyl) phosphate (TCPP) did not decrease but increased during both biological Treatment and physical-chemical Treatment. Mass flow analysis indicated the total removal efficiency of ΣOPEs in aqueous phase was 40.5%, and the polarity-specific removal efficiencies for individual OPE were positively related to their solid-water partition coefficients (Kd). Furthermore, mass balance results showed that 53.1% and 6.3% of the initial OPE mass flow were eventually transferred to the effluents and dewatered sludge, respectively, while the remaining 39.9% and 0.7% were lost due to biodegradation and physical-chemical Treatment, respectively. It was indicated that the activated sludge Treatment system with anaerobic/anoxic/aerobic bioreactors was a major factor in the removal of OPEs from the raw Sewage, while transfer to dewatered sludge governed by hydrophobic interactions was limited during the Sewage Treatment. Meanwhile, the degradation difference of OPEs in activated sludge Treatment was more related with their molecular structure over their hydrophobicity.