【作者】 王乐乐；

【导师】 蓝惠霞；

【作者基本信息】 青岛科技大学 ， 环境工程， 2011， 硕士

【摘要】 活性污泥法因其运行方式灵活、运行费用低、对可生化性物质处理效果好等优点而被广泛使用。但该法通常需要较高的溶解氧浓度（2.0mg/L以上）,导致运行费用高。而较低溶解氧浓度下会发生污泥膨胀问题。本文研究微磁场作用下微氧条件下（溶解氧浓度低于1.0mg/L）,活性污泥的理化特性及处理效果,以期为低溶解氧浓度下活性污泥的应用及降低运行成本提供参数。首先通过实验确定微氧活性污泥中磁粉最佳投加量。结果表明投加量为4g/L,对微生物有明显的促进作用,废水COD_Cr去除率达到最大值93.53%。然后以厌氧污泥为种泥,考察了磁粉产生的微磁场对微氧活性污泥处理效果及理化特性的影响。在磁粉添加量为4g/L,以葡萄糖模拟废水对污泥进行驯化培养。结果表明在培养过程中与不加磁粉相比,添加磁粉反应器中COD_Cr去除率明显高于对照组,而一个周期内pH变化幅度更大。在微氧条件下,微磁场影响下污泥具有良好的沉降性能,整个培养过程中,SVI值均低于100mL/g,而无磁粉反应器中污泥结构松散,沉降性差,SVI值高达200mL/g以上,很容易随水流出反应器。添加磁粉反应器中污泥MLSS明显高于无磁粉反应器。通过测定污泥胞外多聚物（ECPs）总量、PN/PS、絮凝能力（FA）、相对疏水性（RH）及表面电荷（SC）等指标考察微磁场对污泥絮凝性能影响,结果表明,磁粉的存在大大提高了污泥的絮凝性能。最后考察了微磁场作用下pH冲击和毒性废水冲击对微氧活性污泥系统的影响。结果表明磁粉的加入使得反应器具有良好的抗pH冲击和毒性废水冲击的能力,并且在恢复实验中COD_Cr去除率、污泥沉降絮凝性能等理化特性在短时间内即可恢复至正常水平。更多还原

【Abstract】 The activated sludge process has been widely used because it is flexible, low in cost and without secondary pollution. However, due to its requirement of higher dissolved oxygen concentration （higher than 2.0mg/L）, the operation cost was increased. The problem of sludge bulking would occur under environments with low dissolved oxygen concentration. This paper studied the physicochemical properties of activated sludge and its treatment effect in the weak magnetic environment with low dissolved oxygen concentration （lower than 1.0mg/L）, hoping to provide parameters for the application of activated sludge in environments with low dissolved oxygen concentration and the reduction of operation cost.First, experiments were conducted to determine the optimal dosage of magnetic particles in activated sludge with low dissolved oxygen concentration. The results showed that a dosage of 4g/L will obviously promote the activity of microorganism with the removal rate of waste water COD_Cr reaching the peak of 93.53%.Then, with anaerobic sludge as the seed sludge, the paper examined the effect of the weak magnetic environment produced by magnetic particle on the treatment effect of weak aerophilic activated sludge as well as its physicochemical properties. The glucose solution was used to simulate the waste water to culture the sludge with the dosage of the magnetic particle being 4g/L. The result indicated that the reactor with magnetic particles had a higher COD_Cr removal rate than the one without magnetic particles. The range of variation within a period is larger. In the weak aerophilic environment, the sludge under the influence of weak magnetic field had better setting property with the average value of SVI lower than 100mL/g. In the reactor without magnetic particles, the sludge had a loose structure, poor setting property and a SVI value higher than 200mL/g. It would be very easy for it to come out of the reactor with the water. The MLSS of the sludge in the reactor with magnetic particles was obviously higher than that in the reactor without magnetic particles. The influence of the micro-magnetic field on the flocculation capability of the sludge was investigated through the testing of the indices such as the total dose of extracellular polymers （ECPs）, PN/PS, flocculating ability （FA）, relative hydrophobicity （RH） and surface charge （SC） and so on. The testing result showed that the existence of magnetic particles had greatly increased the sludge’s flocculating ability.In the end, the impact of the pH loading shock and toxic wastewater loading shock on the weak aerophilic activated sludge system with the existence of magnetic field was tested. The result showsed that the existence of magnetic particles had given the reactor the ability to offset the impact of the pH loading shock and toxic wastewater loading shock. In addition to that, the COD_Cr removal rate, the sludge setting and flocculating performance as well as other physiochemical properties would soon return to the normal level in the recovery experiment.更多还原