Life cycle environmental and economic viability analysis of CO2 utilization for chemical production in the cement sector

Abstract

Transforming carbon dioxide emissions into marketable chemicals presents an attractive circular economy approach for emissions-intensive industries seeking decarbonization solutions. This study assesses carbon dioxide (CO₂) utilization pathways in Thailand's cement industry for the production of urea, dimethyl ether (DME), and methanol by employing life cycle assessment, levelized cost analysis, and breakeven analysis under dynamic policy scenarios. At the midpoint level, urea and DME demonstrate favorable environmental profiles, with urea showing better performance in 16 out of 18 environmental indicators while DME exhibits advantages in 13 of the assessed categories. Methanol displays a more neutral profile with values close to zero across most categories. At endpoint level, all three CO₂ utilization pathways outperform their conventional fossil-based counterparts across multiple categories. Urea shows the highest CO₂ avoidance potential (3.47 kg CO₂ per kg of CO₂ utilized), which could potentially avoid emissions equivalent to 24 % of Thailand's total national emissions if all cement industry CO₂ were utilized, followed by DME (1.65 kg CO₂, 11 %) and methanol (0.77 kg CO₂, 5 %). The cost analysis reveals that levelized production costs are highest for DME at USD 1544 per tonne, followed by methanol at USD 824 per tonne, and urea at USD 476 per tonne; however, these are significantly higher than conventional production methods. Several factors can close the cost gap between CO₂-derived and conventional chemical production. Lower renewable electricity costs offer the most practical path to economic viability, as solar and wind energy prices have substantially decreased over the past decade, directly benefiting these electricity-intensive processes. Else, carbon credit support would be required ranging from USD 74/t-CO₂ for urea to USD 310/t-CO₂ for DME, with methanol requiring USD 216/t-CO₂. A strategic approach for Thailand would combine declining renewable electricity costs with international market opportunities that value low-carbon products. The findings highlight urea production as the most promising pathway for Thailand's cement industry decarbonization efforts, while emphasizing the critical role of policy support in realizing the potential of these carbon capture and utilization pathways.