title: Citric acid and ethylene diamine tetra-acetic acid as effective washing agents to treat sewage sludge for agricultural reuse.
abstract: This paper presents the effects of different concentrations of citric acid (CA) and ethylene diamine tetra-acetic acid (EDTA) when used as additive reagents for the treatment of sewage sludge for agricultural use. Herein, both the retention of nutrients and removal of metals from the sewage sludge are examined. The average removal rate for the metals after treatment by CA decreased in the order Cu>Pb>Cd>Cr>Zn, while the rates after treatment by EDTA decreased in the order of Pb>Cu>Cr>Cd>Zn. After treatment with CA and EDTA, total nitrogen and total phosphorus concentrations in the sludge decreased, while the content of available nitrogen and Olsen-P increased. In addition, a multi-criteria analysis model-fuzzy analytic network process method (with 3 main factors and 12 assessment sub-factors) was adopted to evaluate the effectiveness of different treatment methods. The results showed that the optimal CA and EDTA concentrations for sewage sludge treatment were 0.60 and 0.125 mol/L, respectively.
authors.affiliation: State Key Laboratory of Urban Storm Water System and Water Environment, Ministry of Education, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China.
authors.forename: Xianghao
authors.initials: X
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Urban Storm Water System and Water Environment, Ministry of Education, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Yan
authors.affiliation: Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing 100085, China.
authors.forename: Hong-Cheng
authors.initials: HC
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Urban Storm Water System and Water Environment, Ministry of Education, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China.
authors.forename: Ying-Ying
authors.initials: YY
authors.lastname: Kou
authors.affiliation: Department of Environmental Engineering, College of Engineering, Korea Maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 606-791, South Korea.
authors.forename: Kyu-Jung
authors.initials: KJ
authors.lastname: Chae
authors.affiliation: Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, South Korea.
authors.forename: In S
authors.initials: IS
authors.lastname: Kim
authors.affiliation: Korea-Europe Environment Energy Expert Forum, 3825 Seodongdae-ro, Pyeongtaek-shi, Gyeonggi-do 450-701, South Korea.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Park
authors.affiliation: Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing 100085, China. Electronic address: ajwang@rcess.ac.cn.
authors.forename: Ai-Jie
authors.initials: AJ
authors.lastname: Wang
mesh_terms: D000383:Agriculture; D019343:Citric Acid / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry*; D017143:Fuzzy Logic; D019216:Metals, Heavy / Q000737:chemistry*; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D059027:Recycling / Q000379:methods*; D012722:Sewage / Q000737:chemistry*; D018505:Waste Management / Q000379:methods*
chemical_list: D019216:Metals, Heavy; D012722:Sewage; D010758:Phosphorus; D019343:Citric Acid; D004492:Edetic Acid; D009584:Nitrogen
keywords: Citric acid; Ethylene diamine tetra-acetic acid; FANP model; Metal removal; Nutrients; Sewage sludge