城市污水厂氨气的来源及排放因子研究

通过对城市污水处理厂进行现场调查和分析,选取广州市猎德污水处理厂的格栅、沉砂池、A-B工艺的曝气池、组合交替式(unitank)生化池、污泥浓缩池及脱水机房采集气样,同时在A-B工艺的曝气池、unitank生化池及A-B工艺的沉淀池采集水样,采用模拟实验测试这些污水处理单元的氨挥发速率,并结合理论计算,研究氨气的来源和排放因子.结果表明,A-B工艺的曝气池和unitank工艺的生化池为城市污水处理厂的主要氨排放源.城市污水处理厂污水的氨气平均挥发速率为21.06μg.m-.2s-1,在此基础上计算出其氨气平均排放因子为0.28 g.m-3,其中A-B工艺曝气池的氨排放因子较高,为0.205 g.m-3;unitank生化池的氨排放因子为0.033 g.m-3;A-B工艺沉淀池的氨排放因子较低,为0.0085 g.m-3.

Ammonia source and emission factor in municipal wastewater treatment plants

This study was conducted to investigate ammonia emission factor of municipal wastewater treatment.Air and water samples were collected from several wastewater treatment units in Guangzhou Liede sewage treatment plant.With the use of a simulation experiment and theoretical calculation,ammonia volatilization rate was determined to calculate the ammonia emission factor of the wastewater treatment plant.Results of the study showed that:(a) A-B aeration tanks and unitank biochemical process pool were main sources of ammonia emissions in Liede wastewater treatment plant;(b) the average ammonia volatilization rate of sewage treatment plant was 21.06 μg·m-2·s-1,the average emission factor was 0.28 g·m-3;and(c) the ammonia emission factor of unitank biochemical process pool was 0.033 g·m-3,the aeration tanks of A-B process had a higher ammonia emission(0.205 g·m-3),while the sedimentation tanks of A-B process had a lower ammonia emission(0.0085 g·m-3).