Preparation of activated sludge embedded particles and the treatment performance of ammonia nitrogen
CHEN Mingfei1,, PENG Zhiying1, JIANG Qiuming2, WANG Xingrong2, YANG Zhike2, WANG Yan1,3, LI Bingbing1, LI Ji1,4,5,, 1.School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China 2.Shanghai SIIC-Longchuang Smarter Energy Technology Co. Ltd., Shanghai 200436, China 3.Wuxi Puhui Environmental Protection Technology Co. Ltd., Wuxi 214028, China 4.Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China 5.Jiangsu University Water Treatment Technology and Materials Collaborative Innovation Center, Suzhou 215009, China
Abstract:Nitrogen removol is one of the most important objectives in sewage treatment. In actual sewage treatment, the nitorgen removal capacity of activated sludge can be easily influenced due to the slow reproduction and metabolism rates, susceptible to shock and easy-loss of nitrifying bacteria, which play the key role in nitrogen removal. So it is of great significance to use immobilized microorganism technology to maintain nitrifying bacteria in biochemical tank. The polyvinyl alcohol (PVA) gel particles modified by polyoxypropylene triol (PPT) can effectively immobilize activated sludge and be used in sewage treatment. This study showed that the modified gel ball had the advantages of good thermal stability, uniform pore distribution, large specific surface area, and large total pore volume. After activity recovery, the embedded and domesticated activated sludge by modified polyvinyl alcohol gel particles showed 18.28% increase in its ammonia oxidizing rate and 2.01% decrease in its respiration rate when compared with the original sludge. Due to the formation of the anaerobic-anoxic-aerobic environment in gel particle, the microbial community diversity indexes, i.e. shannon diversity, species richness, and community evenness, increased, and good ammonia nitrogen removal occurred for immobilized activated sludge. The removal rate of ammonia nitrogen could reach 70% for low strength wastewater treatment. In this research, the properties of modified gel materials and the changes of microbial community and activity in embedded activated sludge were studied and analyzed, which provides reference for the research of gel-embedding activated sludge technology in ammonia nitrogen wastewater treatment. Key words:gel particles/ activated sludge/ microbial activity/ ammonia nitrogen.
图1活性污泥氨氮去除性能 Figure1.Removal performance of ammonia nitrogen by activated sludge
ZHANG G, YE L. Toughening of polyvinyl alcohol hydrogel through co-crosslinking and its wastewater treatment performance by immobilizing with microorganism[J]. Journal of Polymers and the Environment, 2017, 25(2): 229-240. doi: 10.1007/s10924-016-0801-8
PU H T, YANG R Y K. Diffusion of sucrose and yohimbine in calcium alginate gel beads with or without entrapped plant cells[J]. Biotechnology and Bioengineering, 1988, 32(7): 891-896. doi: 10.1002/bit.260320707
WIESMANN R, ZIMELKA W, BAUMGARTL H, et al. Investigation of oxygen transfer through the membrane of polymer hollowspheres by oxygen micro-electrodes[J]. Journal of Biotechnology, 1994, 32(3): 221-229. doi: 10.1016/0168-1656(94)90208-9
BENGTSSON M M, OVREAS L. Planctomycetes dominate biofilms on surfaces of the kelp Laminaria hyperborea[J]. BMC Microbiology, 2010, 10(1): 261-270. doi: 10.1186/1471-2180-10-261
1.School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China 2.Shanghai SIIC-Longchuang Smarter Energy Technology Co. Ltd., Shanghai 200436, China 3.Wuxi Puhui Environmental Protection Technology Co. Ltd., Wuxi 214028, China 4.Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China 5.Jiangsu University Water Treatment Technology and Materials Collaborative Innovation Center, Suzhou 215009, China Received Date: 2019-11-25 Accepted Date: 2020-03-01 Available Online: 2020-11-11 Keywords:gel particles/ activated sludge/ microbial activity/ ammonia nitrogen Abstract:Nitrogen removol is one of the most important objectives in sewage treatment. In actual sewage treatment, the nitorgen removal capacity of activated sludge can be easily influenced due to the slow reproduction and metabolism rates, susceptible to shock and easy-loss of nitrifying bacteria, which play the key role in nitrogen removal. So it is of great significance to use immobilized microorganism technology to maintain nitrifying bacteria in biochemical tank. The polyvinyl alcohol (PVA) gel particles modified by polyoxypropylene triol (PPT) can effectively immobilize activated sludge and be used in sewage treatment. This study showed that the modified gel ball had the advantages of good thermal stability, uniform pore distribution, large specific surface area, and large total pore volume. After activity recovery, the embedded and domesticated activated sludge by modified polyvinyl alcohol gel particles showed 18.28% increase in its ammonia oxidizing rate and 2.01% decrease in its respiration rate when compared with the original sludge. Due to the formation of the anaerobic-anoxic-aerobic environment in gel particle, the microbial community diversity indexes, i.e. shannon diversity, species richness, and community evenness, increased, and good ammonia nitrogen removal occurred for immobilized activated sludge. The removal rate of ammonia nitrogen could reach 70% for low strength wastewater treatment. In this research, the properties of modified gel materials and the changes of microbial community and activity in embedded activated sludge were studied and analyzed, which provides reference for the research of gel-embedding activated sludge technology in ammonia nitrogen wastewater treatment.