温度对Anammox-HAP脱氮性能及污泥特性的影响

Effects of Temperature on Nitrogen Removal Performance and Sludge Characteristics of Anammox-HAP

厌氧氨氧化(Anammox)用于城市污水处理存在生物质持留难、温度波动引起厌氧氨氧化菌(AnAOB)活性降低等问题,采用具有高生物质浓度及更强环境抵抗能力的厌氧氨氧化-羟基磷灰石(Anammox-HAP)颗粒污泥脱氮具有可行性。Anammox-HAP反应器运行了176 d,用于考察不同温度对城污水脱氮性能及污泥特性的影响。首先通过降低总氮(TN)浓度模拟城市污水厂的主流污水并保持氮负荷率(NLR)为3.2 g/(L·d)。在18~35℃下出水TN稳定低于15 mg/L,在主流高负荷条件下保持优异的脱氮性能;在13~18℃,TN去除率明显降低,在13℃降至46.4%。温度提升后,TN去除率在30℃下最高恢复至77.8%,表明低温导致的AnAOB活性下降可逆。在降温的过程中磷去除率为20.2%,低温条件下HAP性质稳定,但Anammox-HAP颗粒污泥的VSS/TSS随着温度的下降而降低。

Anaerobic ammonia oxidation(Anammox)technology has the limitations such as difficulty in biomass retention,and low activity of Anammox bacteria(AnAOB)caused by temperature fluctuations in mainstream municipal wastewater treatment.It is feasible to adopt Anammoxhydroxyapatite(Anammox-HAP)granular sludge with high biomass concentration and stronger environmental resistance to achieve nitrogen removal in mainstream wastewater.An Anammox-HAP reactor had operated for 176 days to treat mainstream wastewater to investigate the nitrogen removal performance and Anammox-HAP granular sludge characteristics at different temperatures.First,mainstream wastewater from municipal wastewater treatment plant by reducing total nitrogen(TN)concentration was simulated,and the nitrogen loading rate(NLR)was kept at 3.2 g/(L·d).At 18-35℃,the concentration of TN in the effluent was stable lower than 15 mg/L and maintained excellent nitrogen removal performance at high nitrogen load conditions;At 13-18℃,the removal rate of TN was significantly reduced,and the minimum was reduced to 46.4% at 13℃.After the temperature increased,the removal rate of TN recovered to a maximum of 77.8% at 30℃,indicating that the decrease in the activity of AnAOB caused by low temperature was reversible.The removal rate of phosphorus in the reactor during decreasing the temperature was 20.2%,and the HAP characteristics were stable at low temperature.However,the VSS/TSS of Anammox-HAP granular sludge decreased with a drop of temperature.