膜-吸附生物反应器处理东江水的中试研究

Pilot-scale study on membrane adsorption bioreactor (MABR) for treating Dong River water

摘要:

针对东江原水,以混凝沉淀作为预处理,采用中试试验,通过与传统砂滤及单独超滤工艺对比,研究膜-吸附生物反应器(MABR)的除污染效能,并考察MABR的膜污染情况.结果表明:MABR对沉后水中有机物的去除能力明显优于传统砂滤和单独超滤,对CODMn和UV254的平均去除率分别达72.4%和89.1%;系统启动完成后,MABR对沉后水中的NH3-N和NO2--N也表现出良好的去除效能,出水NH3-N和NO2--N质量浓度分别稳定在0.2和0.05 mg/L以下.MABR在连续曝气(强度为12.5 m3/(m2.h),以膜池底面积计算)、20 L/(m2.h)通量、每8 h反冲洗5 min的模式下运行时,膜污染较为严重,跨膜压差平均增长速率为0.51 kPa/d,需进一步优化相关参数以减缓膜污染,缩短化学清洗周期.

Abstract:

A pilot-scale membrane adsorption bioreactor(MABR) was carried out for the drinking water treatment from Dong River water with coagulation-sedimentation as pre-treatment.During the experiments,the MABR exhibited much higher capacity for organic matter removal as compared with the conventional sand-filtration and ultra-filtration alone,with the average removal efficiencies of 72.4% and 89.1% for CODMn and UV254,respectively.During the stable operation period after start-up,the MABR also achieved excellent removal for the influent NH3-N and NO-2-N,the effluent concentrations were maintained below 0.2 mg/L and 0.05 mg/L,respectively.In the investigation,the membrane in MABR was operated under the conditions of constant flux(20 L/(m2·h)),continuous aeration(12.5 m3/(m2·h),calculated based on the bottom area of the membrane tank),and backwashing for 5 min after every 8 h of filtration.Under these conditions,obvious membrane fouling was observed for the membrane,with the average trans-membrane pressure development rate of 0.51 kPa/d.To mitigate membrane fouling and to decrease the chemical cleaning time,it is required to further optimize relevant operating parameters of the membrane in MABR.