title: Municipal sludge characteristic changes under different aerating condition in a deep-shaft aeration system.
abstract: A pilot-scale municipal sewage sludge deep-shaft aeration system was implemented in Lanzhou, Gansu Province of China. The reactor depth was 60 m with a diameter of 1.0 m and the sludge to be treated came from a wastewater plant in Lanzhou. In order to obtain the optimum operation conditions, analysis was conducted on the transformations of the volatile suspended solids (VSS), temperature, pH, oxidation-reduction potential (ORP) and pathogens in the deep-shaft reactor under different aeration conditions. Attention was paid to how operating conditions affected the removal efficiency of the VSS and the reaction temperature. As a result, higher volatile solids removal was gained at higher temperature, and the temperature could reach 50.8°C for a complete inactivation of bacteria in the first reaction zone when the deep-shaft aeration system was run for about 18 days. The sludge aeration rate was observed as 1.5 to 1.8 L/(h·L sludge) which enabled the volatile solids removal rate to reach 40.1%. The degradation of VSS occurred under a micro-oxygen environment, and the lowest ORP was found to be -256 mV in the digestive process. Not only aerobic bacteria but also anaerobic and facultative bacteria performed their functions in the reactor.
authors.affiliation: Key Laboratory of Northwest Water Resource Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China E-mail: xiongjiaqing@xauat.edu.cn.
authors.forename: Jiaqing
authors.initials: J
authors.lastname: Xiong
authors.affiliation: Key Laboratory of Northwest Water Resource Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China E-mail: xiongjiaqing@xauat.edu.cn.
authors.forename: Xiaochang C
authors.initials: XC
authors.lastname: Wang
authors.affiliation: Key Laboratory of Northwest Water Resource Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China E-mail: xiongjiaqing@xauat.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Shu
authors.affiliation: Key Laboratory of Northwest Water Resource Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China E-mail: xiongjiaqing@xauat.edu.cn.
authors.forename: Teng
authors.initials: T
authors.lastname: He
authors.affiliation: Key Laboratory of Northwest Water Resource Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China E-mail: xiongjiaqing@xauat.edu.cn.
authors.forename: Yanzheng
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000332:Aerobiosis; D001420:Bacteria, Aerobic / Q000378:metabolism; D019149:Bioreactors; D002681:China; D006358:Hot Temperature; D010100:Oxygen / Q000032:analysis; D010865:Pilot Projects; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D013696:Temperature; D064091:Waste Disposal Facilities; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical
chemical_list: D010100:Oxygen; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical