CO₂ gasification rate analysis and modeling under high CO₂ partial pressure conditions

Coal char was gasified with carbon dioxide using a PDTF and TGA at high temperature and pressure to model gasification reaction rate by using Langmuir-Hinshelwood equation. Test conditions of temperature and partial pressure of the gasifying agent were determined to simulate the conditions in the O₂/CO₂ blown entrained flow coal gasifiers. As results, the gasification reaction rate increases with the increase carbon dioxide partial pressure, although the effect of the partial pressure was suppressed in the region where the partial pressure of carbon dioxide was relatively high. It is observed that the produced carbon monoxide gas acts to be an inhibitor against the gasification reaction and the effect was suppressed as the gaseous temperature increased. It is confirmed that these characteristics can be appropriately expressed by the Langmuir-Hinshelwood equation expression.