A hybrid system of thermophillic anaerobic digestion and heat pump for sludge stabilization and cascade utilization of energy in municipal sewage treatment plant

作者：Tian Lei^*; Shi Lin; Wu Jing; Zhao Pengjuan; Shi Hanchang

来源：Journal of Basic Science and Engineering, 2011, 19(5): 792-798.

DOI：10.3969/j.issn.1005-0930.2011.05.012

• Anaerobic reactions
• Anaerobic sludge digestion
• Chemical energy
• Degradation rate
• Heat pumps
• Heat sources
• Heating system
• Hydraulic retention time
• Long term monitoring
• Municipal sewage treatment plant
• Pilot system
• Production rates
• Reuse water
• Secondary effluent
• Sewage sources
• Sludge
• Sludge stabilization
• Southern China
• Temperature variation
• Thermophilic anaerobic digestion
• Volatile suspended solids

Municipal sewage treatment plants combine sewage and sludge together. Both of which sewage and sludge can be useful resources. A pilot system was bulit by using a moderately-high temperature sewage source heat pump to thermophilic anaerobic sludge digestion at a municipal sewage treatment plant in Southern China, with the aim to simultaneously provide stabilize sludge and reuse water with the recovery of chemical energy in sludge and thermal energy in sewage simultaneously. By using secondary effluent as the heat source, the heat pump canproduce moderately-high grade thermal energy (60°C-70°C) to supply the heating needed (at about 50°C) for the thermophilic anaerobic digestion. The system was designed by using an indirect-type sewage source heat pump and a fast-adjusting sludge heating system. The results show that the sewage source heat pump could stablize the stable anaerobic reaction temperature with the temperature variation within ± 1°C, the digestive gases production rate was 12.4 m3/m3 (sludge moisture content was 96%), and degradation rates of volatile suspended solid reached 52.2% when hydraulic retention time was 5.5 days. Then a long-term monitoring of secondary effluent temperature and water quality, which influenced the stability and efficiency of sewage source heat pump system, was conducted and the impacts were discussed.

• 出版日期2011
• 单位清华大学