ZHANGHan,ZHANGHan,WUBao-li,et al.Anaerobic Digestion Performance of Primary and Secondary Sludge after Hydrothermal Hydrolysis[J].China Water & Wastewater,2023,39(13):32-38.
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Anaerobic Digestion Performance of Primary and Secondary Sludge after Hydrothermal Hydrolysis

China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU] volume: 第39卷 Number: 第13期 Page: 32-38 Column: Date of publication: 2023-07-01
Author(s):
ZHANG　Han1;  ZHANG　Han2;  WU　Bao-li3;  REN　Zheng-ran2;  WANG　Jia-wei2;  QI　Li-ge-wa2;  LI　Xiang-kun1
（1. School of Civil Engineering and Transportation， Hebei University of Technology， Tianjin 300401， China； 2. Beijing Municipal Sewage Resource Engineering Technology Research Center， Science and Technology Research and Development Center of Beijing Urban Drainage Group Co. Ltd.， Beijing 100124，China； 3. North China Municipal Engineering Design and Research Institute Co. Ltd.， Tianjin 300074， China）
Keywords:
primary sludge;  excess activated sludge;  thermal hydrolysis (TH);  anaerobic digestion (AD);  system stability
Abstract:
Taking the sludge of primary sedimentation tank (primary sludge) and secondary sedimentation tank (excess activated sludge) respectively from a large-scale wastewater treatment plant in Beijing as the research object, the anaerobic digestion (AD) performance fed with the pretreatment sludge by high temperature thermal hydrolysis (TH) was investigated. For this purpose, biological methane production potential (BMP), organic matter degradation capacity, hydrolysis, acid production, methane production rate and system stability were all concerned. The results showed that in the AD stage, the gas production rate and organic matter degradation rate of the primary sludge were not significantly higher than that of the excessive activated sludge. Compared with the sludge without TH, the maximum daily gas production rate and TS cumulative gas production rate of excess activated sludge increased by 67% and 80% respectively after TH, and the TCOD degradation rate, total protein degradation rate and total sugar degradation rate increased by 5%, 7% and 14% respectively. The high-temperature TH pretreatment was more effective in improving the hydrolysis rate, acid production rate and methane production rate for excess activated sludge in AD system. For the system stability, a large amount of VFA accumulated in the AD system when fed with primary sludge after TH, which leaded to system instability and gas production decrease. Meanwhile, the AD system fed with excess activated sludge with TH pretreatment kept stable. In general, the excess activated sludge from secondary sedimentation tank was more suitable for high temperature TH pretreatment, however the sludge from primary tank had better feed AD system directively without TH.
Last Update: 2023-07-01