A model for the deposition and wall reaction of molten coal ash slag particle in entrained-flow coal gasifier was proposed.The models of flow

heat and mass transfer

and phase change of slag layer in entrained flow coal gasifier were improved.The method of numerical simulation was developed.Simulations were carried out on a Chinese pilot-scale two-stage dry feed entrained-flow gasifier.The carbon content of slag layer

wall reaction rate

thicknesses of solid slag layer and liquid slag layer

average temperature of slag layer

and average velocity of liquid slag layer were obtained with the proposed model.With increasing oxygen to coal ratio

the thicknesses of solid slag layer and liquid slag layer and carbon content of slag layer at the outlet of gasifier decreased

〖HJ*4/9〗while the average temperature of slag layer increased.The carbon content of slag was about 14%

and carbon conversion of the gasifier was 95.2%

which agreed with the experiment data.It was revealed that wall reaction had significant effects on carbon conversion

carbon content of slag

flow and temperature of slag layer in the gasifier.It might affect the reliability of practical operation of the gasifier.