Process Design and Thermodynamic Evaluation of Flue Gas Conversion into Methanol and Hydrogen Using Wellman–Lord and Amine-Based Capture Technologies

Abstract

The rapid advancement of modern civilization has significantly increased global energy demand, leading to higher levels of harmful emissions. This study proposes an integrated system to convert flue gases into valuable products, specifically hydrogen and methanol. The process begins with flue gas desulfurization (FGD) using the Wellman–Lord method (WLM), selected for its high purity output. The recovered sulfur dioxide is processed in an SO2-depolarized electrolyser(SDE) to produce hydrogen and sulfuric acid. Simultaneously, carbon dioxide is captured via amine-based chemical absorption and subsequently hydrogenated to synthesize methanol. The system achieves an overall thermal efficiency of approximately 48%, producing 12 kg/h of methanol and 110 kg/h of sulfuric acid from a 1000 kg/h flue gas stream. These results demonstrate a promising approach for integrating emission reduction with value-added chemical production.

Keywords

• FlueGas desulfurization
• CO2 Capture
• H2& Methanol Production

Process Design and Thermodynamic Evaluation of Flue Gas Conversion into Methanol and Hydrogen Using Wellman–Lord and Amine-Based Capture Technologies

Abstract

ABSTRACT: The rapid advancement of modern civilization has significantly increased global energy demand, leading to higher levels of harmful emissions. This study proposes an integrated system to convert flue gases into valuable products, specifically hydrogen and methanol. The process begins with flue gas desulfurization (FGD) using the Wellman–Lord method (WLM), selected for its high purity output. The recovered sulfur dioxide is processed in an SO2-depolarized electrolyser(SDE) to produce hydrogen and sulfuric acid. Simultaneously, carbon dioxide is captured via amine-based chemical absorption and subsequently hydrogenated to synthesize methanol. The system achieves an overall thermal efficiency of approximately 48%, producing 12 kg/h of methanol and 110 kg/h of sulfuric acid from a 1000 kg/h flue gas stream. These results demonstrate a promising approach for integrating emission reduction with value-added chemical production.

Keywords

• FlueGas desulfurization
• CO2 Capture
• H2& Methanol Production

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