Abstract: In order to explore the feasibility of oil residue gasification in fixed bed slag gasifier,gasifying oil residue and coal together in the fixed bed slag gasifier can produce clean syngas or gas,so as to broaden the efficient utilization way of oil residue.In this paper,the dispersion effect of oil residue after being sprayed by the nozzle in a fixed pressure bed slag gasifier was studied.Taking Shenhua Coal Direct Liquefaction residue as the research object,the impact of oil residue temperature,oil residue spray velocity and air spray velocity on the spray effect of oil residue under pressure in the industrial-grade pressurized fixed bed slag gasifier was studied by using the numerical simulation software Ansys Fluent.Realizable κ-ε turbulence model was adopted to simulate turbulence flow,and the gas-liquid two-phase flow was simulated by VOF model of Euler-Euler method. The nozzle structure was double-channel. The center channel of the nozzle was used for conveying oil residue,and the annular gap channel was used for conveying gasification agent( replace with air). The optimal spray scheme was determined by analysis and comparison.The following conclusions are drawn: The viscosity of oil residue decreases with the increase of temperature under pressure condition,the viscosity of oil residue drops sharply with the increase of temperature from 210 ℃ to240 ℃; the viscosity of oil residue decreases with the increase of temperature from 240 ℃ to 400 ℃,but the decrease gradually weakens.When the temperature exceeds 400 ℃,the viscosity of oil residue gradually increases with the increase of temperature,which may be caused by polycondensation reaction of oil residue. The spray temperature plays a decisive role in the spray effect of oil residue in the gasifier.The lower the oil residue temperature is,the better the diffusion effect will be after the oil residue spray.However,when the oil residue spray temperature is too low,a large amount of oil residue will begin to flow downward under the influence of gravity,which leads to the relatively short distance of spray due to the great viscosity,and even flow into the slag pool along the wall.There is a relatively optimized spray temperature range.the phenomena of diffusion and adherence should be considered in the selection of the atomization effect of oil residue.The spray effect of oil residue in gasifier under pressure is influenced by pressure and dynamic viscosity.To increase the spray pressure and achieve the same spray effect,it is necessary to increase the spray temperature of the oil residue to reduce the dynamic viscosity of the oil residue.When the spray velocity of oil residue is in the range of 2.5-10.0 m/s,it has little effect on the atomization effect of oil residue in gasifier.In the range of 5-20 m/s,the higher the spray velocity of air is,the better the atomization effect of oil residue in the gasifier is.Considering comprehensively,under 4.5 MPa,the spray temperature of oil residue is 230-260 ℃,the spray velocity of oil residue is about 5 m/s,and the spray velocity of air is about 10 m/s,which is a more suitable spray scheme and the spray comprehensive effect of oil residue is better.