Improving the CO2 performance of cement, part I: utilizing life-cycle assessment and key performance indicators to assess development within the cement industry

The attributional LCA showed that cement products that contain a large proportion of byproducts, in this case, ground granulated blast furnace slag from the iron and steel industry, had the lowest unit emissions of CO2-eq. The difference between the lowest emission product (CEM III/B) and the highest (CEM I) was about 66% per tonne. A simplified LCA model based on six key performance indicators, instead of approximately 50 parameters for the attributional LCA, was established. It showed that Cluster West currently emits about 45% less CO2-eq per tonne of average product compared to 1997. The simplified LCA model can be used effectively to model future changes of both plants and products (which is further discussed in part II and part III).