CO2 Capture in the Cement Industry

Modern cement plants have high energy efficiencies and the scope to reduce CO2 emissions by further efficiency improvements is small. One of the few ways of greatly reducing CO2 production from cement production is CO2 capture and storage (CCS). This paper summarises a study which assessed the technologies that could be used for CO2 capture in cement plants, their costs, and barriers to their use. The work covered new-build cement plants with post-combustion and oxy-combustion CO2 capture. The basis of the study was a 5-stage preheater with precalciner dry process cement plant with a cement output of 1 Mt/y located in NE Scotland, UK. Process Flow Diagrams (PFDs) and heat and mass balance calculations for both options were developed. The plant costs were estimated and the costs per tonne of CO2 emissions avoided and per tonne of cement product determined.