给水厂典型工艺碳排放特征与影响因素

Carbon Emission Characteristics and Influencing Factors of Typical Processes in Drinking Water Treatment Plant

基于实际运行工况和数据监测基础,对天津市给水厂典型工艺的碳排放特征进行研究.给水厂总碳排放强度(以CO_(2)-eq计)为0.254 kg·m^(-3),其中电耗和药耗碳排放占比分别为81.76%和9.15%.给水厂的关键电耗碳排放环节为送水泵房、超滤膜工艺和进水泵房,分别占总电耗碳排放的50.99%~73.51%、17.64%~20.70%和17.97%~22.40%.次氯酸钠对药耗碳排放的贡献率为89.12%~90.30%,其余依次为三氯化铁、聚合氯化铝和硫酸铵.传统净水工艺单元的电耗碳排放强度依次为:进水泵房>快滤池>沉淀池,在深度处理工艺线中依次为:进水泵房>超滤膜>机械混凝>澄清池.快滤池工艺线和超滤膜工艺线的碳排放强度分别为0.0709 kg·m^(-3)和0.1090 kg·m^(-3).超滤膜工艺能节约23%的药剂用量,而电耗碳排放是传统处理工艺的2倍.对关键环节的碳排放影响因素分析结果表明,浊度、pH、氨氮和温度等原水水质参数与次氯酸钠碳排放强度显著相关;出厂水压力、日送水量与送水泵房碳排放强度呈显著的线性回归关系,相关水质和水压调控措施可以有效减少给水厂碳排放.

Based on the actual operating conditions and data monitoring,the carbon emission characteristics of typical processes of a drinking water treatment plant(DWTP)in Tianjin were studied.The total carbon emission intensity measured by CO_(2)-eq was 0.254 kg∙m^(-3),and the proportion of carbon emissions from electricity consumption and reagent consumption was 81.76% and 9.15%,respectively.The key carbon emission sectors of electricity consumption were the water supply pump house,ultrafiltration membrane process,and inlet pump house,which accounted for 50.99%-73.51%,17.64%-20.70%,and 17.97%-22.40% of the total carbon emission from electricity consumption in the DWTP,respectively.The contribution of sodium hypochlorite to the carbon emission of reagent consumption was 89.12%-90.30%,followed by ferric chloride,PAC,and ammonium sulfate.In the traditional water purification process,the carbon emission intensity of the process unit was in the order of inlet pump house>rapid filter>sedimentation tank.The order in the ultrafiltration membrane advanced treatment process was inlet pump house>ultrafiltration membrane>mechanical coagulation>clarification tank.The carbon emission intensity of the rapid filter process and the ultrafiltration membrane process were 0.0709 kg·m^(-3) and 0.1090 kg·m^(-3),respectively.The ultrafiltration membrane process could save 23% of the reagent consumption,and its carbon emission of electricity consumption was twice that of the traditional treatment process.The analysis of factors affecting carbon emission in key sectors showed that the raw water quality parameters such as turbidity,pH,ammonia nitrogen,temperature,etc.,were significantly correlated with the carbon emission intensity of sodium hypochlorite.There was a significant linear regression relationship between ex-factory water pressure,daily water supply,and carbon emission intensity of the water supply pump house.The control measures of water quality and water pressure can effectively reduce the carbon emissions of the DWTP.