Toward sustainable recycled methanol production from CO2 and steel by-product gases in South Korea; process design and assessment

Methanol is receiving considerable attention as an alternative fuel because of its potential role as a transitional option in mitigating greenhouse gas emissions and enabling the transition towards biofuels. Recycled methanol, produced using captured CO2 or industrial by-product gases, emerges as an attractive alternative in South Korea, especially considering the excessive emissions from its energy and industrial sectors. However, assessing technological superiority amongst a range of alternatives remains challenging. This study aims to assess and compare various methanol production pathways utilizing captured CO2 and by-product gases from steel industry within context of South Korea. The selected technologies are either currently in industrial use or pivotal for future industrial applications. A unified process design and assessment framework was employed to model and simulate eight technological conversion processes. These processes underwent evaluation based on key performance indicators, accompanied by comprehensive techno-economic and environmental life cycle assessments. Additionally, comparisons were made with conventional fossil-based methanol production, considering different hydrogen and electricity production routes. This study provides valuable insights into the viability of recycled methanol pathways in terms of process performance, economic and environmental feasibility and will facilitate the practical implementation of recycled methanol, contributing towards achieving carbon neutrality objectives. •Eight methanol production routes using waste carbon sources in South Korea are evaluated.•A unified process design framework is employed to model and simulate the processes.•Techno-economic and life cycle assessments uncover the optimal methanol production routes.•Various hydrogen and electricity pathways are considered to propose utilization strategies.•Hydrogen stands out the most crucial element in recycled methanol production.