Gasification reactivity of coal gasification fine slag and its separatedcarbon-rich residues

With the widely application of entrained-flow coal gasification technology in China′s coal chemical industry, the productionof coal gasification fine slag is increasing year by year. At present, the resource utilization of gasification fine slag has become one of thedifficult problems in the treatment of solid waste in coal chemical industry. In this paper, gasification fine slag with different carbon contents and its separated carbon-rich residues were selected as the research objects. The structural parameters such as composition, porestructure and microstructure were analyzed. The gasification reactivity of coal gasification fine slag under CO2 atmosphere was investigatedbased on thermogravimetric analyzer. The gasification reaction kinetics was analyzed by iso-conversional method, and the internal relationship between the structural characteristics of coal gasification fine slags and its carbon-rich residues and their gasification reactivity was revealed. The results show that the pore structure is the key factor affecting the gasification reactivity of gasification fine slag and its separated carbon-rich residues, and the samples with developed pore structure have higher gasification reactivity. With the increase of heatingrate in gasification process, the gasification reaction range of gasification fine slag and its carbon-rich residues shiftes to high temperature.In addition, the gasification reaction activation energy of gasification fine slag and carbon-rich residues with relatively high fixed carbon content decreases with the increase of conversion rate, while the gasification reaction activation energy of gasification fine slag and carbon-rich residues with high ash content of the sample itself increases with the increase of conversion rate. The research results provide theoretical guidance for the resource utilization of gasification fine slag and its separated carbon-rich residues.