A review of carbon capture and utilisation as a CO₂abatement opportunity within the EWF nexus

Carbon capture and utilisation (CCU) is considered an important CO2 mitigation strategy to support and compliment carbon capture and storage (CCS) objectives for the abatement and sequestration of CO2. It represents various pathways that utilise CO2 as a feedstock in process systems or otherwise for the generation of value-added commodities. The CO2 used can be captured from different sources including power plants and industrial activities via several existing carbon capture and separation technologies that ensure a pure and safe CO2 supply. CCU pathways are mainly divided into five wide-ranging categories: CO2 conversion to chemicals and fuels, mineral carbonation, enhanced oil recovery, biological conversion, and direct CO2 utilisation. This study reviews the main CCU pathways and highlights their intra-sectoral and inter-sectoral opportunities within the energy water and food (EWF) systems, which is an important resource management concept. It also discusses the global status of CCU operational projects, research and development efforts directed toward CCU deployment, and important decision-making directions when integrating CCU with the EWF nexus. This review highlights that CCU pathways provide several cross-sectoral opportunities within the EWF sectors, by allaying resource competition between sectors and proposing co/tri-integrated solutions for securing EWF resources. Future efforts in this regard should be directed towards studying the EWF nexus within CCU routes in a comprehensive, quantitative, and holistic approach to identify and measure all trade-offs and synergies within EWF sectors, and to optimise CCU supply chains.