某热水解+厌氧消化污泥处理工程热能浅析

Analysis on Thermal Energy of a Sludge Treatment Project Adopting Thermal Hydrolysis and Anaerobic Digestion Process

以采用“热水解+高温厌氧消化+板框脱水+带式干化”工艺的某市政污泥集中处置工程为例,收集该工程一个自然年内的生产进泥泥质、沼气产量及各工段热能消耗等实际生产数据,分析泥质变化趋势与不同运行方式下的热能平衡情况。结果表明,污泥有机质与含固率呈季节性变化。当有机质含量为30%~46.16%的污泥采用全工艺链处理时,处理1 t干污泥(DS)需补充沼气19~92 m^(3),工程方可实现热能平衡。不考虑带式干化时,污泥有机质含量应高于36.88%方可保证工程能量平衡。高湿度季节以外的清灰作业可有效避免锅炉受热面积灰导致的短期锅炉热效率下降,并防止因积灰回潮导致的受热面整体腐蚀。

This paper collected the actual operational data of a municipal sludge centralized disposal project with process consisting of thermal hydrolysis,high temperature anaerobic digestion,plate frame dewatering and belt drying in a natural year,such as the quality of sludge,biogas yield and thermal energy consumption of each section,and analyzed the variation of sludge quality and the thermal energy balance under different operational modes.The organic matter and solid content of the sludge changed seasonally.When the sludge with organic matter content of 30%-46.16%was treated in the whole process chain,biogas with volume of 19-92 m^(3) should be added to treat each ton of dry sludge(DS),so that the project could achieve thermal energy balance.When the belt drying was not operated,the organic matter content of the sludge should be higher than 36.88%to achieve the thermal energy balance of the system.The ash‑cleaning outside the season of high humidity effectively avoided the short‑term reduction of boiler thermal efficiency caused by ash accumulation on boiler heating surface and prevented the overall corrosion of heating surface caused by moisture regain of accumulated ash.