摘要
在前期研究模糊综合评价方法的基础上建立了一套普适性的给水厂混凝剂评估验证流程方法,通过烧杯试验、中试优化评估混凝剂适用性及优选投加量,并结合技术经济性因素在实际水厂开展了规模化的验证,以期为水厂混凝剂的适用性筛选及其优化使用提供借鉴。烧杯试验采用标准流程对水厂常用的PAFC及PAC进行评价对比,中试阶段对烧杯试验所选投加量进行验证,生产验证主要是在经济投加量下,检测出水各项指标。结果显示:PAFC对目标水体的适用效果较好且优于PAC。烧杯及中试验证发现药剂的最佳投加量为4mg/L,但在生产验证阶段兼顾了技术经济性因素,确定最适投加量应为2mg/L。在此情况下,其出水浊度、TOC、COD_(Mn)以及UV_(254)的去除率分别达到了89.87%、7.5%、33.01%以及44.57%,絮体平均粒径达到了625μm,投药成本为0.07元/m~3。通过全流程评估验证综合评价:目标给水厂当前所用混凝剂以及投加量是相对科学合理的。
In order to evaluate and select the coagulant in the water treatment plant scientifically and effectively.In the early stage of the research study in this paper the fuzzy comprehensive evaluation method on the basis of the established a set of general assessment process validation method for waterworks coagulants,mainly through beaker test,pilot test optimization evaluation applicability and coagulant dosing quantity optimization,and combined with the technical economical factor in actual water carried out large-scale practical validation,so as to the applicability of the waterworks coagulant selection and optimization of use for reference.In the beaker test,standard process is adopted to evaluate and compare the PAFC and PAC commonly used in the water treatment plant.In the pilot test stage,the selected dosage of the beaker test is verified.The production verification is mainly to test the results of water indexes under the economic dosage.The results show that PAFC is better than PAC in the application of target water.In the beaker test and pilot test,it is found that the optimal dosage is 4 mg/L,but the technical and economic factors are taken into account in the production verification stage,and the optimal dosage is determined to be 2 mg/L.The removal rates of turbidity,TOC,CODMnand UV254 reach 89.87%,7.5%,33.01% and 44.57%,respectively.The comprehensive evaluation is verified through the whole process evaluation that the target coagulant and dosage used in the water plant are relatively scientific and reasonable.
引文
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