(569bg) Chemical Reaction and Physical Behavior of Carbonaceous Particles on High-Temperature Liquid Surface

The entrained flow gasification technology has been widely used to produce syngas (CO+H₂) for chemical industries and power generation plant. The liquid slag discharge process adopted by this technology will capture unreacted particles, which will affect the overall conversion of solid fuels and the long-term stable operation of the device. Our research work has focused on the reaction and relevant behaviours, such as gasification, combustion, and fragmentation, of captured carbonaceous particles on the high-temperature liquid surface in the entrained flow gasifier. A visual experimental platform has been built to conduct this series of explorations and research work, with the combination of modelling. The results showed that the high-temperature liquid surface, namely molten slag, increased the particle temperature and improved the carbon conversion, comparing the gasification of original char particles. A reaction model with thermal analysis was proposed to analyse and reveal the characteristics of the char gasification on the molten slag surface. However, when studying the combustion behaviours of captured particles on the molten slag surface, a delayed conversion result was found and the heat flux was conducting from particle to slag. Additionally, we investigated the particle evolution during the gasification process on the molten slag surface, with the effects of different coal ranks. A two-staged reaction mode, including particle shrinkage and particle fragmentation, was found and related to natural properties of carbonaceous particles, such as moisture and volatiles. Our recent work also found the element migration behaviour between particles and liquid surface, which provides a further insight on the interfacial reaction. The mentioned above work will help to provide guidance for the comprehensive model, reactor design, and operation optimization of gasifier.