Biological nutrient removal by internal circulation upflow sludge blanket reactor after landfill leachate pretreatment
Biological nutrient removal by internal circulation upflow sludge blanket reactor after landfill leachate pretreatment作者机构:State Key Laboratory of Biogeology and Environmental GeologyChina University of Geosciences Thi Qar University Al-Mustansiryiah University College of Engineering
出 版 物:《Journal of Environmental Sciences》 (环境科学学报(英文版))
年 卷 期:2013年第25卷第10期
页 面:2130-2137页
核心收录:
学科分类:083002[工学-环境工程] 0830[工学-环境科学与工程(可授工学、理学、农学学位)] 08[工学]
基 金:supported by the Hubei Provincial Science and Technology Department(No.2006AA305A05) the China Scholarship Council (CSC) China University of Geosciences (CUG) for the financial support of this research
主 题:landfill leachate anaerobic-anoxic-aerobic (A^2/O) bioreactor biological nutrient removal combined treatment
摘 要:The removal of biological nutrient from mature landfill leachate with a high nitrogen load by an internal circulation upflow sludge blanket (ICUSB) reactor was studied. The reactor is a set of anaerobic-anoxic-aerobic (A^2/O) bioreactors, developed on the basis of an expended granular sludge blanket (EGSB), granular sequencing batch reactor (GSBR) and intermittent cycle extended aeration system (ICEAS). Leachate was subjected to stripping by agitation process and poly ferric sulfate coagulation as a pretreatment process, in order to reduce both ammonia toxicity to microorganisms and the organic contents. The reactor was operated under three different operating systems, consisting of recycling sludge with air (A^2/O), recycling sludge without air (low oxygen) and a combination of both (A^2/O and low oxygen). The lowest effluent nutrient levels were realised by the combined system of A^2/O and low oxygen, which resulted in effluent of chemical oxygen demand (COD), NH3-N and biological oxygen demand (BOD5) concentrations of 98.20, 13.50 and 22.50 mg/L. The optimal operating conditions for the efficient removal of biological nutrient using the ICUSB reactor were examined to evaluate the influence of the parameters on its performance. The results showed that average removal efflciencies of COD and NH3- N of 96.49% and 99.39%, respectively were achieved under the condition of a hydraulic retention time of 12 hr, including 4 hr of pumping air into the reactor, with dissolved oxygen at an rate of 4 mg/L and an upflow velocity 2 m/hr. These combined processes were successfully employed and effectively decreased pollutant loading.