【作者】 张志永；

【导师】 潘涌璋； 金腊华；

【作者基本信息】 暨南大学 ， 环境工程， 2007， 硕士

【摘要】 生物膜法是一种高效的废水生物处理工艺，生物载体则是该工艺的核心部分，其性能直接影响和制约着生物膜法工艺的处理效果。本研究以强化生物脱氮和污泥减量化为主要目标，选取天然多孔矿物——浮石、网络状塑料外壳、磁铁为原料，试验开发出一种新型生物磁性载体，并将该载体应用于生物膜反应器进行废水处理试验研究。首先考察了浮石的物理性能，使用扫描电子显微镜观察浮石的微观结构，并进行了浮石吸附试验和挂膜试验研究，在此基础上开发出磁性载体。然后采用磁性载体生物膜反应器和非磁性载体生物膜反应器进行平行试验，考察了载体的挂膜性能，进行了模拟废水处理试验以探讨工艺的最优运行参数，在此基础上，对实际生活污水和焦化废水进行了处理试验，最后探讨了磁性载体生物膜反应器中污染物的降解机理。论文主要研究结果如下：（1）天然浮石具有粗糙表面和多孔结构，平均孔径在15μm左右，孔隙率为69.5～71.8％，吸水率为58～61％，适合于微生物的附着，孔壁厚1-2μm，强度较高。（2）挂膜试验结果表明：生物磁性载体的挂膜性能明显占优，可在5d内完成挂膜，而非磁性载体则须8d，且磁性载体对COD_Cr、NH₄⁺-N的去除率比非磁性载体分别高出5％和20％左右。（3）以模拟废水为处理对象，探讨了DO、HRT、载体磁场强度等对生物膜反应器处理效果的影响。结果表明：载体中心磁场强度为200Gs、DO=2.0～3.5mg/L、HRT=8h的条件下，系统运行效果最优，出水COD_Cr、NH₄⁺-N稳定在30mg/L和5mg/L左右，去除率分别达90％和80％；出水总氮在20mg/L左右，去除率在50％以上；出水总磷约为4mg/L，去除率仅为20％。磁性载体反应器内60d的污泥量为163.25g，明显低于平行试验的非磁性载体反应器内的231.76g，说明磁场的存在有利于污泥减量化。（4）在DO=2.0～3.5mg/L、HRT=5h的条件下，校园生活污水经磁性载体生物膜反应器处理后，出水COD_Cr稳定在20mg/L左右，NH₄⁺-N在5mg/L以下，两者的去除率均在90％左右；出水总氮在15mg/L左右，去除率在50％以上。在DO>2.0mg/L、HRT=12h的条件下，焦化废水经处理后，出水COD_Cr在100mg/L左右，去除率约为80％，但对NH₄⁺-N的处理效果不是很理想。（5）对磁性载体生物膜反应器运行结果和微生物学特性的研究表明，载体内的弱磁场能刺激微生物活性，明显有利于硝化作用和污泥减量化。更多还原

【Abstract】 The biofilm process is a highly efficient technology in the wastewater treatment. Biocarrier is the key factor for this method, and its performance directly influences and restricts the efficiency of the process. In the experiment, a magnetic biocarrier was first developed in order to improve the result of biological nitrogen removal and sludge reduction for wastewater treatment, which was made up of pumice-a kind of natural porous mineral, magnet and retiform plastic ball. Then the biofilm reactor with the magnetic biocarrier was used to treat the wastewater.In order to develop the magnetic biocarrier, the physical performance of pumice was firstly studied, its microstructure was observed by SEM, and the adsorption experiment and the biofilm formation performance experiment were performed. Then the parallel test of biofilm reactor with magnetic biocarrier and the one with nonmagnetic biocarrier was employed to study the biofilm formation performance of magnetic biocarrier. The reactors were also used to treat the simulated wastewater in order to find out the optimal operating parameters. And then the domestic sewage and coking wastewater were treated by biofilm reactor with magnetic biocarrier. Finally, the degradation mechanism of pollutant in the reactor was studied. The main conclusions were gained as follows:（1） The natural pumice has rough surface, porous structure with average pore diameter of 15μm, porosity of 69.5～71.8%, water absorption of 58～61% and thicker pore walls of 1～2μm, which offers a nicer living condition for microbe.（2） Compared to the biofilm reactor with nonmagnetic biocarrier, the biofilm formation performance of the magnetic biocarrier was better, and the period of biofilm formation reduced from 8 days to 5 days, the removal rates of COD_Cr and NH₄⁺-N by the biofilm reactor with magnetic biocarrier were increased by 5% and 20% respectively.（3） The two biofilm reactors were employed to treat simulated wastewater by changing the operating parameters—DO, HRT, and magnetic field intensity. The treated effect is best under the conditions of the central magnetic field intensity of biocarrier 200Gs, DO 2.0～3.5mg/L and HRT 8h. The concentration of COD_Cr, NH₄⁺-N, TN and TP of effluent were about 30mg/L, 5mg/L and 20mg/L, and the removal rates were 90%, 80%, 50% and 20% respectively after the treatment. Compared to the biofilm reactor with nonmagnetic carrier, the activated sludge in the biofilm reactor with magnetic carrier was reduced from 231.76g to 163.25g, which showed that magnetic field could improve the efficiency of sludge reduction.（4） Under the condition of DO 2.0～3.5mg/L, HRT 5h, the removal rates of COD, NH₄⁺-N and TN were 90%, 90% and 50% respectively, with COD content of 10.25mg/L, NH₄⁺-N content of under 5mg/L, TN content of 15mg/L in the effluent of domestic sewage. The coking wastewater was treated under the condition of DO 2.0～3.5mg/L and HRT 5h, the removal rates of COD was 80% with the content of about 100mg/L, but the removal rates of NH₄⁺-N was very low.（5） The experimental result showed that the low magnetic field could stimulate the microbe activity, and it is helpful to nitrification and sludge reduction in wastewater treatment.更多还原