CH_4 emission and conversion from A^2O and SBR processes in full-scale wastewater treatment plants  

作　　者：Yan Liu Xiang Cheng Xiaoxiu Lun Dezhi Sun 

机构地区：[1]College of Environmental Science and Engineering, Beijing Forestry University

出　　处：《Journal of Environmental Sciences》2014年第1期224-230,共7页环境科学学报（英文版）

基　　金：supported by the Fundamental Research Funds for the Central Universities,China(No.TD2011-22);the China Welfare Funds for Environmental Protection(No.201009053);the Beijing Municipal Science and Technology Commission(No.Z111100058911003);the National Natural Science Fundation of China(No.51008023,51078034,51278051)

摘　　要：Wastewater treatment systems are important anthropogenic sources of CH4 emission. A full-scale experiment was carried out to monitor the CH4 emission from anoxic/anaerobic/oxic process （A2O） and sequencing batch reactor （SBR） wastewater treatment plants （WWTPs） for one year from May 2011 to April 2012. The main emission unit of the A2O process was an oxic tank, accounting for 76.2% of CH4 emissions; the main emission unit of the SBR process was the feeding and aeration phase, accounting for 99.5% of CH4 emissions. CH4 can be produced in the anaerobic condition, such as in the primary settling tank and anaerobic tank of the A2O process. While CH4 can be consumed in anoxic denitrification or the aeration condition, such as in the anoxic tank and oxic tank of the A2O process and the feeding and aeration phase of the SBR process. The CH4 emission flux and the dissolved CH4 concentration rapidly decreased in the oxic tank of the A2O process. These metrics increased during the first half of the phase and then decreased during the latter half of the phase in the feeding and aeration phase of the SBR process. The CH4 oxidation rate ranged from 32.47% to 89.52% （mean： 67.96%） in the A2O process and from 12.65% to 88.31% （mean： 47.62%） in the SBR process. The mean CH4 emission factors were 0.182 g/ton of wastewater and 24.75 g CH4/（person.year） for the A2O process, and 0.457 g/ton of wastewater and 36.55 g CH4/（person.year） for the SBR process.Wastewater treatment systems are important anthropogenic sources of CH4 emission. A full-scale experiment was carried out to monitor the CH4 emission from anoxic/anaerobic/oxic process （A2O） and sequencing batch reactor （SBR） wastewater treatment plants （WWTPs） for one year from May 2011 to April 2012. The main emission unit of the A2O process was an oxic tank, accounting for 76.2% of CH4 emissions; the main emission unit of the SBR process was the feeding and aeration phase, accounting for 99.5% of CH4 emissions. CH4 can be produced in the anaerobic condition, such as in the primary settling tank and anaerobic tank of the A2O process. While CH4 can be consumed in anoxic denitrification or the aeration condition, such as in the anoxic tank and oxic tank of the A2O process and the feeding and aeration phase of the SBR process. The CH4 emission flux and the dissolved CH4 concentration rapidly decreased in the oxic tank of the A2O process. These metrics increased during the first half of the phase and then decreased during the latter half of the phase in the feeding and aeration phase of the SBR process. The CH4 oxidation rate ranged from 32.47% to 89.52% （mean： 67.96%） in the A2O process and from 12.65% to 88.31% （mean： 47.62%） in the SBR process. The mean CH4 emission factors were 0.182 g/ton of wastewater and 24.75 g CH4/（person.year） for the A2O process, and 0.457 g/ton of wastewater and 36.55 g CH4/（person.year） for the SBR process.

关 键 词：CH4 emission production and consumption wastewater treatment plant A2O SBR 

分 类 号：X703[环境科学与工程—环境工程] X171