Calcium looping appears as one of the most promising technologies for CO2 capture in short-medium term plants featuring the combustion of fossil fuels. Ca-looping (CaL) is a regenerative process which takes advantage of the capacity of Calcium Oxide-based sorbents in capturing the CO2 from combustion gases by means of sequential carbonation-calcination cycles. CaL technology appears very promising for CO2 capture from cement plants, since the CaO-rich purge stream which must be extracted from the process can be a valuable raw material for clinker production.The aim of this study is to investigate from the technical and economic side the benefits arising from the integration between a coal-fired power plant with CaL process for CO2 capture and a cement plant using the CaL purge to substitute part of the raw meal. The main parameters affecting the CaL process are varied and the effects on both the plant performance and the final cost of clinker and electricityare discussed
This paper present the techno-economic assessment of an MEA-based CO2capture from a cement plant and the importance of the steam supply on the costs. The evaluations present the energy performances of the CO2capture process based on a cement plant with a clinker capacity of 3,000 t/d. The cost evaluation lead to a cost of cement of 45 â\u82¬/tcementwithout capture, while the cost of cement with CO2capture is estimated to 81 â\u82¬/tcement, resulting in a CO2avoided cost of 83 â\u82¬/tCO2,avoided. As the steam consumption accounts for close to half of the CO2avoided cost, the impact of six alternative steam supply scenarios are considered. The evaluations show that the CO2avoided cost can decrease by up to 35% depending on the steam supply and electricity price. However the possibility of these steam supply alternatives are specific to the considered cement plant, emphasizing therefore that CO2avoided cost from cement shall rather be given as a range depending on the steam supply than as a unique value as often illustrated in the literature
1 December 2017 in International Journal of Greenhouse Gas Control
In this work, the integration of Calcium looping (CaL) process into a cement plant for post-combustion CO2capture is assessed via process simulations. In the proposed scheme, the carbonator of the CaL process is used as an end-of-pipe unit to capture the CO2from the cement kiln gas. From the results obtained, it is demonstrated that CO2capture efficiencies of the order of 90% are achievable, with CaL reactors operating in conditions not far from those demonstrated for application in power plants. The integration of the tail-end CaL process results in a significant increase of the total fuel consumption (about two to three times higher) compared to the benchmark cement plant without CO2capture. On the other hand, the heat from the CaL process can be recovered by a steam cycle producing decarbonized electric power that may exceed the needs of the plant auxiliaries (including the ASU and the CO2compression and purification unit), exporting in this way electricity to the grid and so resulting in CO2emission credits from a life cycle perspective. The resulting specific primary energy consumption for CO2avoided (SPECCA) highly depends on the reference power generation technology considered, and it ranges between 2.7 and 3.7 MJLHV/kgCO2in a coal-fired power generation scenario. As for the retrofittability of existing cement plants, the operation of the suspension preheating tower after the implementation of the CaL unit, as well as the position of the CaL carbonator with respect to the raw mill, have been assessed. Based on the results obtained, no critical issues have been found from a technical point of view in the adoption of the tail-end CaL process in existing cement kilns
1 September 2019 in International Journal of Greenhouse Gas Control