亚硝化反应器的启动及控制因子研究

Startup and controlling factors for the nitrition reactor

为探究亚硝化反应器的启动,在常温条件下,经190d运行,对温度、pH、游离氨(FA)和溶解氧进行了监测.在SBR运行方式下,在进水中投加铵盐,使氨氮质量浓度达200mg·L-1、溶解氧为0.2mg·L-1,在连续流运行方式下停止投加铵盐,维持溶解氧为0.2mg·L-1.结果表明,高氨氮进水氨氧化菌(AOB)可以得到强化增殖,亚硝酸盐迅速积累;连续流低氨氮进水仍可实现亚硝酸的稳定积累,但当溶解氧质量浓度>0.5mg·L-1时,硝酸化现象严重,而恢复低溶解氧一段时间后,亚硝酸盐又得到重新积累;氨氧化菌虽对温降敏感,但升温后硝化性能立即恢复.高氨氮可加快亚硝化反应器的启动,而低溶解氧却是维持亚硝酸盐积累的控制因子.

Temperature, pH, free ammonia （FA） and dissolved oxygen （DO） were monitored to study the start-up of nitrition reactor at room temperature during 150 d. First, in the SBR operation mode, ammonium salt was added in the influent to make ammom＇a concentration reach 200 mg · L^-1 and DO reach 0. 2 mg · L^-1. Then in the continuous stream mode, DO was maintained stable at 0. 2 mg · L^-1 and ammonium salt was not added. The result shows that the proliferation of AOB can be enhanced in high concentration ammonia water, so nitrite can be accumulated rapidly. In the continuous low concentration ammonia influent reactor, accumulation of nitrition can be achieved when DO is 0. 2 mg · L^-1, and it turns to be full nitrification under 0. 5 mg · L^-1, but nitrition can be accumulated again after DO is resumed. The resistant mutation of ammonia oxidizer is poor with temperature decrease, but the nitrification performance can be recovered immediately after temperature rise. The start-up of nitrition reactor can be started rapidly under high ammonia, and low DO is the major factor for accumulation of nitrition.