基于国内水泥生产现状的碳排放因子测算

水泥生产过程中碳排放因子的测算是计算水泥碳排放量的基础,为了准确测算我国水泥行业熟料煅烧阶段碳酸盐矿物分解释放CO2的碳排放因子,就需要对水泥生产线上相关样品做成分测定和综合分析.通过对国内近百条代表性较强的水泥生产线上的生料、熟料、水泥、石灰石、燃煤等样品进行钙、镁、烧失量、碳酸盐等化学成分的定量分析,并考虑新型干法窑和立窑两种生产工艺类型的差别,分析测算了基于国内水泥生产的工艺碳排放因子.结果表明:生料碳酸盐法测算碳排放因子的结果较熟料法的结果低约10kgCO2/tcl;不同窑型的碳排放因子存在明显差异,新型干法窑的碳排放因子多集中在500~520kgCO2/tcl,立窑碳排放因子多集中在480~500kgCO2/tcl;多数熟料含有少量碳酸盐.生料碳酸盐法不涉及燃煤灰分的化学成分,可以规避燃煤灰分成分的影响,测算碳排放因子采用生料碳酸盐法较准确,并且应基于不同窑型,同时考虑碳酸盐分解率问题.

Calculation of CO2 emission factor on the present situation of the domestic cement production

CO2 emission factor was the foundation of the calculation of CO2 emissions, and it was necessary that a large amount of samples at onsite cement production stages should be analyzed and studied for accurately calculating CO2 emission factor during the decomposition of carbonate minerals in calcinations for Chinese cement industry. Quantitative analysis was Londucted on calcium, magnesium, loss on ignition, carbonate and other chemical component in raw material, clinker, cement, limestone, coal and other samples from about 100 production lines in China. At the same time, it compared the differences between new suspension preheater kilns (NSP kilns) and shaft kilns. The results showed that CO2 emission factor calculated by raw material carbonate method was about 10kgCO2/tcl lower than clinker method. There were obvious differences within different types of cement kilns, for example, the emission factors of NSP kilns were in the range of 500~520kgCO2/tcl and shaft kilns were 480~500kgCO2/tcl. The majority of clinker contained a small amount of carbonate. The raw material carbonate method did not involve chemical composition of coal ash, and it could avoid the discrepancy of coal ash components. This implied that raw material carbonate method was relatively accurate, However it should be based on different types of kilns and carbonate decomposition rate.