厌氧附着膜膨胀床反应器预处理有机氯农药废水的研究

Pretreatment of organochlorine pesticide wastewater by anaerobic attached film expanded bed(AAFEB) approach

针对有机氯农药废水可生化性差的特点，研究了采用厌氧膨胀床颗粒活性炭反应器对其预处理以提高可生化性的效果。未经处理的有机氯农药废水及经混凝、Fenton氧化处理后的有机氯农药废水分别进入厌氧反应器，在进水pH为6．8～7．2，水力停留时间为48h，有机物容积负荷为1．41～3．19kgCOD／m^2．d时，3种废水的出水B／C值分别为0．35、0．41和0．42；出水COD分别为1280、1050和659mg／L；出水色度分别为50倍（灰白）、20倍（灰白）和20倍（灰白）。从运行稳定、经济的角度，选择混凝一厌氧组合作为该农药废水的预处理工艺。研究提出采用单位表面面积生物膜底物降解速率LW作为厌氧膨胀床反应器的设计指标，并根据试验数据得出厌氧膨胀床颗粒活性炭反应器的动力学模型，为工程设计及运行管理提供依据。

In view of the characteristics of organochlorine pesticide wastewater ,a pilot AAFEB was adopted to pre-treat the wastewater. The inlet of AAFEB included the crude wastewater, the wastewater pretreated by Fenton reagent or by flocculation. For normal operating under conditions when the pH, nominal hydraulic retention time（HRT） and volumetric COD load rate of the reactor in range of 6.8 - 7. 2, 48 hours and 1. 41 - 3. 19 kg COD/m^3. d respectively, the average effluent of B/C value, COD and colourity were 0.35,1280 mg/L, 50; 0.41,1050 mg/L, 20; 0.42,659 mg/L,20 respectively. The optimal pretreatment process included flocculation and AAFEB. COD area load rate LW was key design index and a kinetic model of organic matter degradation on AAFEB was established. The study provided a reliable basis for practical engineering design and operation of this wastewater.