化学混凝与活性炭吸附联用处理水源水研究

The experiment of source water of Nanning Daming Mountain treating under the application of chemical coagulation and activated carbon adsorption

化学混凝法和活性炭吸附是水处理的常用工艺,其中化学混凝法效率较低,活性炭吸附成本较高,然而这两种工艺联用是否经济有效并不清楚.本研究探讨了粒状/粉末活性炭吸附、化学混凝法、混凝-活性炭吸附3种工艺处理大明山水源水的效率和成本.结果表明:在各工艺的最优条件下,混凝-粉末活性炭工艺的效率最高,其最优条件是不调节原水pH(pH=6.35～6.69),三氯化铁(40 mg/L)混凝,0.2 mg/mL粉末活性炭吸附.经此工艺处理后原水的色度(35度～37度)降为1.5度,浊度(4 NTU～6 NTU)降为0.5 NTU,COD(19 mg/L～22 mg/L)降为4.5 mg/L,去除率分别达到95.7%,91.6%,79.4%,已达到生活饮用水标准,并且此工艺成本仅相当于单纯粉末活性炭工艺的37.2%.综上,选择混凝-粉末活性炭工艺处理南宁大明山水源水在技术和经济上具有可行性.

Chemical coagulation and active carbon adsorption are two common processes in treating water. Chemical coagulation remains certain inefficiency, and active carbon adsorption high costly. Therefore, it should be made clear whether the combination of the two processes for water treating were cost-effective. We investigated the efficiency and cost of the three processes ： powdered/granular activated carbon adsorption （ACA）, chemical coagulation （CC）, powdered activated carbon adsorption-chemical coagulation （ACA-CC）, for treating source water of Daming Mountain in Nanning. The results showed that the powdered ACA-CC process had the highest efficiency in water treating among the three processes at their own optimal conditions. The optimal conditions of the powdered ACA-CC process were pH keeping （pH=6.35-6.69）, FeC13 coagulation at 40 mg/L, powdered activated carbon adsorption at 0.2 mg/mL. Once the ACA-CC process done, chroma of the source water decreased from 35- 37 to 1.52, turbidity from 4-6 to 0.50 NTU, and COD from 19-22 to 4.5 mg/L. The removal rates respectively amounted to 95.7% ,91.6% and 79.4%. Besides, the cost of the powdered ACA-CC process was 37.2 percent of that of ACA process. Overall, the powdered ACA-CC process for treating source water of Nanning Daming Mountain is the most feasible way considering technology and economy.