Cement Energy Environment

10 The process is divided in two basic steps: 1. The capture of CO 2 by “carbonation” of CaO to form CaCO 3 in a reactor operating around 650°C: CaO + CO 2 - CaCO 3 + heat; the heat development is negligible here. 2. Oxyfuel calcination in a reactor operating above 900-920°C, which makes the CaO available again and releases a gas stream of nearly pure CO 2 : CaCO 3 + heat - CaO + CO 2 In the highly integrated Calcium Looping process configuration the carbonator is used to capture the CO 2 contained in the kiln flue gases and the pre calciner of the cement plant is oxy-fuelled and it coincides with the calciner of the CaL process. the CaO-rich pre-calcined raw meal produced in the calciner is broken down into two streams: one goes to the rotary kiln for clinker production, the other to the carbonator, to act as the sorbent of the CO 2 released in the kiln. The solid stream with re-carbonated raw meal is returned to the calciner to be regenerated, together with the raw meal coming from the pre-heating tower. CO 2 from fresh raw meal calcination, from kiln fuel combustion and from calciner fuel combustion is collected in the single flue gas stream exiting the calciner. CO 2 - rich gas to CPU CO 2 - recycle Recarbonated fresh sirbent to calciner CO 2 - lean ue gas Fresh raw meal Calcined raw meal to carbinator Calcined raw meal to rotary kiln II Air Fuel Fresh raw meal Fresh raw meal Fuel Rawmeal preheater Calciner Carbonator Rotary kiln Rawmeal preheater II Rawmeal preheater III In order to demonstrate the technical and economic feasibility of the integrated CaL process in large, retrofitted cement plants under realistic conditions, a test plant is currently being built in Italy within the scope of the EU Horizon 2020 CLEANKER project (www.cleanker.eu ). As a technology partner, the IKN GmbH engineering firm from Neustadt is one of 13 international consortium members in this project, which is financed through EUR 8.9 million of EU funds. The objective is to lay the foundation for companies in the EU to use this technology on an industrial basis. https:// cordis.europa.eu/project/rcn/211877/factsheet/en Picture Source: Politechnico di Milano Implementation of an integrated CaL concept in a cement plant