好氧颗粒污泥膜生物反应器的运行特性

以人工合成模拟废水对好氧颗粒污泥膜生物反应器(MBR)的运行特性和膜污染进行了研究.结果表明:在HRT为6h,溶氧浓度为4～6mg.L^-1,COD的容积负荷为7.24kg·(m³·d)^-1的条件下,COD的去除率可达96%以上.当NH₃-N的容积负荷为0.17kg·(m³·d)^-1时,NH₃-N的去除率可达60%.COD/N比的变化,对好氧颗粒污泥MBR的COD及NH₃-N去除率基本没有影响.稳定运行过程时,MBR中好氧颗粒污泥浓度(MLSS)基本维持在14～16mg·L^-1.较高的污泥浓度和颗粒污泥内部缺氧和厌氧环境的存在,使MBR中硝化和反硝化过程能同时存在.同时,比较了2种不同形态的活性污泥(颗粒污泥和絮状污泥)在MBR运行过程中膜通量的变化趋势,结果表明,颗粒污泥MBR膜通量的下降速度明显比絮状污泥MBR的下降速度慢很多,且通过空气反冲或用水清洗即可使通量基本恢复.

Characteristics of Aerobic Granular Sludge Membrane Bioreactor for Wastewater Treatment

Characteristics of aerobic granular sludge membrane bioreactor (MBR) and the membrane fouling were studied with synthetic wastewater. Experimental results showed that COD removal rate could be reached over 96% under the conditions of HRT = 6h, DO 4 - 6 mg x L(-1) and the volumetric load of COD = 7.24 kg x (m3 x d)(-1). When the volumetric load of NH3-N was 0.17 kg x (m3 x d)(-1), the removal rate of NH3-N was about 60%. The variations of the COD/N ratio could not affect the removal of COD and NH3-N. During the stable operation process, MLSS of the reactor was as high as 14 - 16 mg x L(-1), which could conduce simultaneous nitrification-denitrification, as the anoxic and anaerobic microorganisms might be existed in the core of granular sludge. In addition, the membrane flux of MBR of two different configurations of sludge, granular sludge and floccular sludge, was compared. The flux reduction of granular sludge MBR was much lower than that of floccular sludge MBR. Moreover, the membrane permeability of the granular sludge MBR could be regained simply by backwashing with aeration or washing the membrane with water.