Environmental and economic assessment of carbon capture and utilization at coal-fired power plant in Thailand

Greenhouse gas reduction from large point sources has been of interest for global warming mitigation. Coal-fired power plants with carbon capture and utilization (CCU) technology can minimize carbon emissions. In this study, Life Cycle Assessment (LCA) methodology is applied to evaluate the potential environmental risks of capturing carbon dioxide at the coal-fired power plant in Thailand and utilizing it in alternative methanol (CO2_MeOH) and formic acid (CO2_FA) productions through direct CO2 hydrogenation. The study aims to achieve low carbon growth and sustainable development success in Thailand. According to the analyses, the negative carbon feedstock provides larger decarbonization in the CO2-based productions than the conventional productions (i.e., -862 vs. 712 kgCO2-eq in a ton of MeOH production while 1.96E3 vs. 4.11E3 kgCO2-eq in a ton of FA production). Despite the net negative carbon emissions, CO2_MeOH production can rise 6 out of 8 investigated environmental impact indicators, when 2 out of those would increase in CO2_FA production. The maximum impact scores as a result of the energy demand of the carbon capture can be reduced by integrating the waste heat recovery from the carbon removal process. Consequently, the higher impacts would be 4 out of 8 indicators in the CO2_MeOH production, whereas the CO2_FA production remains the same pattern.Furthermore, the investment costs of CCU projects are estimated on a unit price basis to strengthen an economy with a clean energy transition. The findings revealed that the process with the waste heat integration could decrease not only the related environmental risks but also the investment cost. However, total production costs (1227 $/tCO2_MeOH & 1044 $/tCO2_FA) are still expensive to compete with the conventional production prices (295-368 $/tMeOH & 546 $/tFA) and the current global market prices (750 $/tMeOH & 500-800 $/tFA), that could be lowered if low electricity cost was available. Selling by-product oxygen from CO2_MeOH production and cheaper catalysts from local or global markets can reduce the total production cost.