膜生物反应器低温污水处理效能研究

Effectiveness research of membrane bioreactor process treating low-temperature wastewater

通过连续实验,考察了温度变化对膜生物反应器除污染效果的影响,重点研究了低温条件下(10±2)℃溶解氧(DO)和水力停留时间(HRT)对膜生物反应器净化效能的影响规律。研究结果表明,温度的突然降低会导致污泥的氧吸收速率下降,系统对COD的去除效率从90.1%迅速降低至68.2%,但经过1个月的低温运行后,活性污泥的氧吸收速率会有所提高,系统对COD的去除效率也逐渐恢复至88.1%;在低温条件下,分别考察了DO和HRT变化对COD和TN的去除效率的影响,确定了反应器内适宜的DO范围为0.8～1.5 mg/L,HRT为8 h,此条件下COD的平均去除率在90%以上,TN的平均去除率在65%以上。

The effect of the temperature change on the removal efficiency of pollutant was investigated by continuous operation of membrane bioreactor.The influences of dissolved oxygen（DO） and hydraulic retention time（HRT） on the purification performance of MBR at low temperature（10 ± 2）℃ were mainly studied.The results showed that the sharp decrease of the temperature resulted in the decrease of the oxygen uptake rate of sludge,meanwhile the removal efficiency of COD rapidly decreased from 90.1% to 68.2%.However,after a month of low-temperature operation,the oxygen uptake rate of the activated sludge increased,while COD removal efficiency gradually recovered to 88.1%.Then further study focused on the influence of DO and HRT on the removal efficiency of COD and TN at low temperatures.The optimal DO value ranged from 0.8 to 1.5 mg/L and optimal HRT was 8 h,under this condition,the average removal efficiencies of COD and TN were more than 90% and 65%,respectively.