Bringing value to the chemical industry from capture, storage and use of CO2: A dynamic LCA of formic acid production

Low carbon options for the chemical industry include switching from fossil to renewable energy, adopting new low-carbon production processes, along with retrofitting current plants with carbon capture for ulterior use (CCU technologies) or storage (CCS). In this paper, we combine a dynamic Life Cycle Assessment (d-LCA) with economic analysis to explore a potential transition to low-carbon manufacture of formic acid. We propose new methods to enable early technical, environmental and economic assessment of formic acid manufacture by electrochemical reduction of CO2 (CCU), and compare this production route to the conventional synthesis pathways and to storing CO2 in geological storage (CCS). Both CCU and CCS reduce carbon emissions in particular scenarios, although the uncertainty in results suggests that further research and scale-up validation are needed to clarify the relative emission reduction compared to conventional process pathways. There are trade-offs between resource security, cost and emissions between CCU and CCS systems. As expected, the CCS technology yields greater reductions in CO2 emissions than the CCU scenarios and the conventional processes. However, compared to CCS systems, CCU has better economic potential and lower fossil consumption, especially when powered by renewable electricity. The integration of renewable energy in the chemical industry has an important climate mitigation role, especially for processes with high electrical and thermal energy demands.

The authors are grateful for the funding of the Spanish Ministry of Economy and Competitiveness through the Projects CTM2016-76176-C2-1-R (AEI/FEDER, UE) and CTQ2016-76231-C2-1-R (AEI/FEDER, UE). The UCL team would like to acknowledge funding from the UK Natural Environment Research Council through the project Comparative assessment and region-specific optimisation of GGR, NERC Reference: NE/P019900/1. Rubén Aldaco thanks the Ministry of Sciences, Innovation and Universities of Spanish Government for their financial support via the research fellowship Salvador de Madariaga Program (PRX18/00027).