The effects of combined ultrasound and low temperature thermal pretreatments on disintegration and anaerobic digestion of waste activated sludge
XU Hui-min1, HE Guo-fu1, DAI Xiao-hu2,3, XIANG Wei-ning1,4
1. College of Ecological and Environmental Science, East China Normal University, Shanghai 200241, China;
2. National Engineering Research Center for Urban Pollution Control, Shanghai 200092, China;
3. College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China;
4. Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai 200241, China
To explore the effects of ultrasound and low temperature thermal pretreatments on anaerobic digestion of waste activated sludge (WAS), ultrasound, thermal, and combined (ultrasound+thermal) pretreatments were conducted. Taking temperature and specific energy as control parameters, disintegration degree of SCOD(DD) and organic disintegration before and after pretreatments were measured. Prior to anaerobic digestion, combined pretreatment significantly improved DD and soluble organic matter concentrations which were better than the sum of ultrasound and thermal pretreatments. The combination of ultrasound and thermal pretreatment under specific energy of 12000kJ/kg TS and temperature of 80℃, DD and soluble organic concentration were 4.04%、36.62mg/L higher than the sum of pretreatment alone. Besides, there was a highly linear relationship between DD and actual energies imparted to sludge (R2=0.977). Combined pretreatments improved the methane production of WAS during anaerobic digestion by 30.2%~55.4% than untreated sludge. It was also found that DD and anaerobic biodegradability had a conical relationship (R2=0.821). The optimum anaerobic biodegradability, 877.76LCH4/kg VSSremoved, was achieved with combined pretreatment at temperature of 80℃ and specific energy of 12000kJ/kg TS.
徐慧敏, 何国富, 戴晓虎, 象伟宁. 超声联合低温热水解促进剩余污泥破解和厌氧消化的研究[J]. 中国环境科学, 2016, 36(9): 2703-2708.
XU Hui-min, HE Guo-fu, DAI Xiao-hu, XIANG Wei-ning. The effects of combined ultrasound and low temperature thermal pretreatments on disintegration and anaerobic digestion of waste activated sludge. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(9): 2703-2708.
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