At the site of the Mergelstetten cement plant in southern Germany, the consortium intends to build and operate its own demonstration plant on a semi-industrial scale, where the so-called oxyfuel process will be applied for CO2 capture. In the future, the captured CO2 will be used to produce so-called "reFuels", which are climate-neutral synthetic fuels such as kerosene for air traffic, with the help of renewable electrical energy.
The cement industry is intensively searching for solutions to return in particular the CO2 emissions, that is unavoidably arising during the burning of limestone, into the production cycle or to use them for new products. To achieve this, the CO2 has to be captured during the cement production process.
To demonstrate such CO2 capture methods in practice, four European cement manufacturers Buzzi Unicem - Dyckerhoff; HeidelbergCement, SCHWENK Zement, and Vicat, founded the joint venture CI4C – Cement Innovation for Climate – at the end of 2019. The aim of the 'catch4climate' project is to create the basis for a large-scale application of CO2 capture technologies in cement plants enabling the later use of CO2 as a raw material in other processes (CCU, CCS).
The Oxyfuel process (from Oxy = oxygen and fuel) is a clinker burning process in which pure oxygen is introduced into the cement kiln instead of air. Thanks to the pure oxygen, no nitrogen gets into the burning process, which leads to the creation of highly concentrated CO2. The aim is to capture almost 100% of the CO2 emissions from a cement plant in a cost-efficient manner. By using this technology, the European cement industry could achieve a significant reduction in process-related CO2 emissions and thus make an important contribution to climate protection. The realisation of the project is still subject to the public research funding to be applied for.
The CI4C consortium has already entered the planning phase and is cooperating closely with the federal state of Baden-Württemberg in the 'catch4climate' pilot project in Mergelstetten. Together with the Prime Minister and the Transport Minister of the federal state, a corresponding 'Letter of Intent' was signed in Stuttgart, Germany, on 18 November 2020.