Economics of CO2 utilisation technologies in the cement industry

Being among the biggest emitters of anthropogenic CO2, the cement industry requires rapid solutions in order to foster a development towards a sustainable future [1]. A concept developed in recent years, which could possibly procure CO2 emission reductions for many industrial sectors, including cement production, is the so-called ‘carbon capture and utilisation’ (CCU). It has become a model which attracts researchers, policy makers and entrepreneurs in search of sustainability solutions. The general idea is not to emit CO2 directly, but to use the produced CO2 as a feedstock for the production of goods. At the end of their lifetime, many CCU products can be incinerated and the resulting CO2 can be circled back again. Therefore, CCU could potentially play a role in the de-fossilization of certain industry sectors and foster the development towards circularity in industrial processes. A major hurdle for implementing CCU technologies is often their economic viability as well as the social acceptance for using such technologies [2]. Hence, assessments regarding the economic and social impacts of CCU technologies are needed [3]. A technological concept developed in this field is the so called ‘accelerated carbonation’ process. Hereby, CO2 is reacted with activated minerals to form carbonates [4]. The carbonates could potentially be used for multiple purposes, such as fillers, cement additives or for land reclamation projects [5]. Some policy advice reports use the accelerated carbonation process as a positive example for the utilisation of CO2 as a feedstock, because unlike most other CCU concepts, the carbonation reaction is energetically favourable [6]. Nevertheless, accelerated carbonation routes lack detailed and comparable economic assessments in literature [4]. In this contribution, economic assessments of several carbonation routes will be presented, uncovering the advantages of certain routes towards an economically viable implementation. Moreover, the evaluation of the circumstances under which these novel technologies become economically feasible as well as the analysis of key factors which can be influenced in order to promote economic feasibility will be investigated. Hereby, the methodology of a recently published guideline for techno economic assessments of CCU technologies[3] will be used. Understanding the economics of CO2 utilisation routes in the cement industry is essential for their further development as well as deployment and can help decision makers to derive sustainability strategies.