The Experts below are selected from a list of 18822 Experts worldwide ranked by ideXlab platform

Hideki Harada - One of the best experts on this subject based on the ideXlab platform.

  • prospects for a self sustainable Sewage Treatment System a case study on full scale uasb System in india s yamuna river basin
    Journal of Environmental Management, 2006
    Co-Authors: Nobuyuki Sato, Akiyoshi Ohashi, Tsutomu Okubo, Takashi Onodera, Hideki Harada
    Abstract:

    Abstract The government of India decided to launch a project to implement 16 full-scale Upflow Anaerobic Sludge Blanket (UASB) reactors (with a total capacity of 598,000 m 3 /d) in the Yamuna River basin under its Yamuna Action Plan (YAP). A polishing pond called the Final Polishing Unit (FPU) was utilized for post-Treatment. This paper evaluates the Sewage Treatment efficiency of the combined System of full-scale UASB reactors and polishing ponds under Indian climatic conditions. Results have shown that the effluent from the Sewage Treatment plants (STPs) investigated failed to comply with applicable discharge standards in terms of BOD, SS, and fecal coliform removal. Therefore, it is proposed that such proper operation and maintenance as removing excess sludge and scum be conducted in order to increase Treatment efficiency. Moreover, trained and experienced workers are also required to operate and maintain the Systems, along with a scientific approach.

  • a low cost municipal Sewage Treatment System witha combination of uasb and the fourth generation downflow hanging sponge reactors
    Water Science and Technology, 2005
    Co-Authors: Madan Tandukar, Shigeki Uemura, Izarul Machdar, Akiyoshi Ohashi, Hideki Harada
    Abstract:

    This paper presents an evaluation of the process performance of a pilot-scale “fourth generation” downflow hanging sponge (DHS) post-Treatment System combined with a UASB preTreatment unit treating municipal wastewater. After the successful operation of the second- and third-generation DHS reactors, the fourth-generation DHS reactor was developed to overcome a few shortcomings of its predecessors. This reactor was designed to further enhance the Treatment efficiency and simplify the construction process in real scale, especially for the application in developing countries. Configuration of the reactor was modified to enhance the dissolution of air into the wastewater and to avert the possible clogging of the reactor especially during sudden washout from the UASB reactor. The whole System was operated at a total hydraulic retention time (HRT) of 8 h (UASB: 6 h and DHS: 2 h) for a period of over 600 days.The combined System was able to remove 96% of unfiltered BOD with only 9 mg/L remaining in the final effluent. Likewise, F. coli were removed by 3.45 log with the final count of 10 3 to 10 4 MPN/100 ml. Nutrient removal by the System was also satisfactory.

  • removal of indigenous coliphages and fecal coliforms by a novel Sewage Treatment System consisting of uasb and dhs units
    Water Science and Technology, 2002
    Co-Authors: Shigeki Uemura, K Takahashi, A Takaishi, Izarul Machdar, Akiyoshi Ohashi, Hideki Harada
    Abstract:

    A novel Sewage Treatment System, which consists of an upflow anaerobic sludge blanket (UASB) pre-Treatment unit and the following downflow hanging sponge (DHS) unit for polishing up the UASB effluent, was developed as a cost-effective and easy-maintenance Sewage Treatment System for developing countries. A long-term experiment with actual Sewage was conducted in order to evaluate its Treatment efficiency of organic substances, nutrients, and pathogen indicator microorganisms such as total coliphages, F + -specific RNA coliphages (RNA coliphages), and fecal coliforms. The main objective of this paper is to investigate the removal efficiency of those indicator microorganisms by the UASB-DHS combined System. The results obtained from the continuous flow experiment indicated a fairly promising removal of the indicator microorganisms, i.e., the log 10 reductions of total coliphages, RNA coliphages, and fecal coliforms (based on Sewage and DHS effluent) achieved were 2.01 log, 2.02 log, and 2.57 log, respectively. The UASB-DHS combined System was superior to the conventional activated sludge process in the reduction of fecal coliforms, but in the reductions of total and RNA coliphages, the System showed somewhat less removal efficiency. The vertical reducing patterns of the indicator microorganisms along the DHS reactor were also discussed.

  • a novel and cost effective Sewage Treatment System consisting of uasb pre Treatment and aerobic post Treatment units for developing countries
    Water Science and Technology, 1997
    Co-Authors: Izarul Machda, Akiyoshi Ohashi, Hideki Harada, Yuji Sekiguchi, Hiroyuki Okui, Kyoko Ueki
    Abstract:

    A novel Sewage Treatment System was proposed, which consists of a UASB anaerobic pre-Treatment unit and the following DHS (downflow hanging sponge-cubes) aerobic post-Treatment unit, as a low-cost and easy-maintenance process for developing countries. Over six months experiment by feeding Sewage our proposed System achieved 94% of total-COD removal, 81% of soluble-COD removal, and nearly perfect SS removal and total-BOD removal at the overall HRT of 8.3 hr (7 hr in UASB and 1.3 hr in DHS unit). Moreover, the DHS reactor was capable of performing high (73–78%) nitrification. Our whole System requires neither external aeration input nor withdrawal of excess sludge.

Yueping Ren - One of the best experts on this subject based on the ideXlab platform.

  • impacts of sludge retention time on sludge characteristics and membrane fouling in a submerged osmotic membrane bioreactor
    Bioresource Technology, 2014
    Co-Authors: Xinhua Wang, Yao Chen, Bo Yuan, Yueping Ren
    Abstract:

    Anaerobic–oxic membrane bioreactor (AOMBR) has been proposed as a highly effective method in municipal and industrial wastewater Treatment. In this study, according to the Sewage Treatment System in a campus, long-term experiments were conducted to assess the impacts of the sludge retention time (SRT) on sludge characteristics and membrane fouling, and the sludge parameters include biomass concentration, particle size distribution, extracellular polymeric substances (EPS), soluble microbial products (SMPs), and specific resistance to filtration (SRF). Our results clearly demonstrated that SRT was one of the most important factors influencing sludge characteristics, and different sludge characteristics resulted in different membrane fouling degrees. A better Treatment and filtration performances were observed at the SRT of 30 days compared to two SRTs of 10 and 90 days. Among these parameters, SMP had the most significant correlation with the membrane fouling rate (dTMP/dt), and it had a negative impact on membrane filtration performance. The impact of SRT on membrane fouling process was discussed further by filtration models. At 10 days SRT, the complete-standard blocking model curve had a comparatively higher goodness-of-fit with the fouling process, and at 30 and 90 days SRT, the cake-standard blocking model curve had a relatively higher goodness-of-fit with respective fouling process.

Xiufu Hua - One of the best experts on this subject based on the ideXlab platform.

  • Impacts of sludge retention time on sludge characteristics and membrane fouling in a submerged anaerobic-oxic membrane bioreactor.
    Applied microbiology and biotechnology, 2015
    Co-Authors: Xiaomei Zhang, Xiuping Yue, Zhiqiang Liu, Xiufu Hua
    Abstract:

    Anaerobic–oxic membrane bioreactor (AOMBR) has been proposed as a highly effective method in municipal and industrial wastewater Treatment. In this study, according to the Sewage Treatment System in a campus, long-term experiments were conducted to assess the impacts of the sludge retention time (SRT) on sludge characteristics and membrane fouling, and the sludge parameters include biomass concentration, particle size distribution, extracellular polymeric substances (EPS), soluble microbial products (SMPs), and specific resistance to filtration (SRF). Our results clearly demonstrated that SRT was one of the most important factors influencing sludge characteristics, and different sludge characteristics resulted in different membrane fouling degrees. A better Treatment and filtration performances were observed at the SRT of 30 days compared to two SRTs of 10 and 90 days. Among these parameters, SMP had the most significant correlation with the membrane fouling rate (dTMP/dt), and it had a negative impact on membrane filtration performance. The impact of SRT on membrane fouling process was discussed further by filtration models. At 10 days SRT, the complete-standard blocking model curve had a comparatively higher goodness-of-fit with the fouling process, and at 30 and 90 days SRT, the cake-standard blocking model curve had a relatively higher goodness-of-fit with respective fouling process.

Akiyoshi Ohashi - One of the best experts on this subject based on the ideXlab platform.

  • prospects for a self sustainable Sewage Treatment System a case study on full scale uasb System in india s yamuna river basin
    Journal of Environmental Management, 2006
    Co-Authors: Nobuyuki Sato, Akiyoshi Ohashi, Tsutomu Okubo, Takashi Onodera, Hideki Harada
    Abstract:

    Abstract The government of India decided to launch a project to implement 16 full-scale Upflow Anaerobic Sludge Blanket (UASB) reactors (with a total capacity of 598,000 m 3 /d) in the Yamuna River basin under its Yamuna Action Plan (YAP). A polishing pond called the Final Polishing Unit (FPU) was utilized for post-Treatment. This paper evaluates the Sewage Treatment efficiency of the combined System of full-scale UASB reactors and polishing ponds under Indian climatic conditions. Results have shown that the effluent from the Sewage Treatment plants (STPs) investigated failed to comply with applicable discharge standards in terms of BOD, SS, and fecal coliform removal. Therefore, it is proposed that such proper operation and maintenance as removing excess sludge and scum be conducted in order to increase Treatment efficiency. Moreover, trained and experienced workers are also required to operate and maintain the Systems, along with a scientific approach.

  • a low cost municipal Sewage Treatment System witha combination of uasb and the fourth generation downflow hanging sponge reactors
    Water Science and Technology, 2005
    Co-Authors: Madan Tandukar, Shigeki Uemura, Izarul Machdar, Akiyoshi Ohashi, Hideki Harada
    Abstract:

    This paper presents an evaluation of the process performance of a pilot-scale “fourth generation” downflow hanging sponge (DHS) post-Treatment System combined with a UASB preTreatment unit treating municipal wastewater. After the successful operation of the second- and third-generation DHS reactors, the fourth-generation DHS reactor was developed to overcome a few shortcomings of its predecessors. This reactor was designed to further enhance the Treatment efficiency and simplify the construction process in real scale, especially for the application in developing countries. Configuration of the reactor was modified to enhance the dissolution of air into the wastewater and to avert the possible clogging of the reactor especially during sudden washout from the UASB reactor. The whole System was operated at a total hydraulic retention time (HRT) of 8 h (UASB: 6 h and DHS: 2 h) for a period of over 600 days.The combined System was able to remove 96% of unfiltered BOD with only 9 mg/L remaining in the final effluent. Likewise, F. coli were removed by 3.45 log with the final count of 10 3 to 10 4 MPN/100 ml. Nutrient removal by the System was also satisfactory.

  • removal of indigenous coliphages and fecal coliforms by a novel Sewage Treatment System consisting of uasb and dhs units
    Water Science and Technology, 2002
    Co-Authors: Shigeki Uemura, K Takahashi, A Takaishi, Izarul Machdar, Akiyoshi Ohashi, Hideki Harada
    Abstract:

    A novel Sewage Treatment System, which consists of an upflow anaerobic sludge blanket (UASB) pre-Treatment unit and the following downflow hanging sponge (DHS) unit for polishing up the UASB effluent, was developed as a cost-effective and easy-maintenance Sewage Treatment System for developing countries. A long-term experiment with actual Sewage was conducted in order to evaluate its Treatment efficiency of organic substances, nutrients, and pathogen indicator microorganisms such as total coliphages, F + -specific RNA coliphages (RNA coliphages), and fecal coliforms. The main objective of this paper is to investigate the removal efficiency of those indicator microorganisms by the UASB-DHS combined System. The results obtained from the continuous flow experiment indicated a fairly promising removal of the indicator microorganisms, i.e., the log 10 reductions of total coliphages, RNA coliphages, and fecal coliforms (based on Sewage and DHS effluent) achieved were 2.01 log, 2.02 log, and 2.57 log, respectively. The UASB-DHS combined System was superior to the conventional activated sludge process in the reduction of fecal coliforms, but in the reductions of total and RNA coliphages, the System showed somewhat less removal efficiency. The vertical reducing patterns of the indicator microorganisms along the DHS reactor were also discussed.

  • a novel and cost effective Sewage Treatment System consisting of uasb pre Treatment and aerobic post Treatment units for developing countries
    Water Science and Technology, 1997
    Co-Authors: Izarul Machda, Akiyoshi Ohashi, Hideki Harada, Yuji Sekiguchi, Hiroyuki Okui, Kyoko Ueki
    Abstract:

    A novel Sewage Treatment System was proposed, which consists of a UASB anaerobic pre-Treatment unit and the following DHS (downflow hanging sponge-cubes) aerobic post-Treatment unit, as a low-cost and easy-maintenance process for developing countries. Over six months experiment by feeding Sewage our proposed System achieved 94% of total-COD removal, 81% of soluble-COD removal, and nearly perfect SS removal and total-BOD removal at the overall HRT of 8.3 hr (7 hr in UASB and 1.3 hr in DHS unit). Moreover, the DHS reactor was capable of performing high (73–78%) nitrification. Our whole System requires neither external aeration input nor withdrawal of excess sludge.

Xinhua Wang - One of the best experts on this subject based on the ideXlab platform.

  • impacts of sludge retention time on sludge characteristics and membrane fouling in a submerged osmotic membrane bioreactor
    Bioresource Technology, 2014
    Co-Authors: Xinhua Wang, Yao Chen, Bo Yuan, Yueping Ren
    Abstract:

    Anaerobic–oxic membrane bioreactor (AOMBR) has been proposed as a highly effective method in municipal and industrial wastewater Treatment. In this study, according to the Sewage Treatment System in a campus, long-term experiments were conducted to assess the impacts of the sludge retention time (SRT) on sludge characteristics and membrane fouling, and the sludge parameters include biomass concentration, particle size distribution, extracellular polymeric substances (EPS), soluble microbial products (SMPs), and specific resistance to filtration (SRF). Our results clearly demonstrated that SRT was one of the most important factors influencing sludge characteristics, and different sludge characteristics resulted in different membrane fouling degrees. A better Treatment and filtration performances were observed at the SRT of 30 days compared to two SRTs of 10 and 90 days. Among these parameters, SMP had the most significant correlation with the membrane fouling rate (dTMP/dt), and it had a negative impact on membrane filtration performance. The impact of SRT on membrane fouling process was discussed further by filtration models. At 10 days SRT, the complete-standard blocking model curve had a comparatively higher goodness-of-fit with the fouling process, and at 30 and 90 days SRT, the cake-standard blocking model curve had a relatively higher goodness-of-fit with respective fouling process.