Incineration And Optimization Simulation Of600t/d Municipal Solid Waste Incinerator

With the continuous increase of China’s urban population and the output of urban domestic waste,the phenomenon of"garbage besieging the city"is becoming more and more serious.It is urgent to properly deal with a large number of urban domestic waste.Municipal solid waste incineration can achieve the goal of reduction,harmlessness and recycling.Recycling the waste heat after incineration can also reduce the demand for fossil energy to a certain extent.This thesis simulates the600t/d municipal solid waste incinerator provided by Anhui Deyu Environmental Engineering Equipment Co.,Ltd.,and studies the incineration under different parameter variables（grate operation speed,fuel particle size and rear arch structure）,in order to provide some reference and guidance for the optimal operation of waste incineration plant.Firstly,a 750t/d waste incinerator is numerically simulated,and the simulation results are compared with the field operation data to verify the reliability of the simulation method.Through the numerical simulation of the incinerator provided by the client through the coupling method of FLIC and fluent software,the conclusions are as follows:the water evaporation stage along the length of the grate is long;The secondary air in the furnace has obvious disturbance and oxygen supplement effect on gas-phase incineration;The area with high velocity is mainly distributed in the secondary air outlet and the back wall of the first flue;The low concentration area of O₂is mainly distributed in the middle area of the grate and the middle and lower part of the burner;The concentration of CO is high in the middle section of the grate and small in other areas.The numerical simulation method is used to optimize the design of the incinerator provided by the client,and the effects of grate operation speed,fuel particle size and rear arch structure（rear arch height and rear arch angle）on the incineration in the incinerator are studied to obtain the optimal working condition.The results show that the lower the operation speed of the grate,the more complete the incineration,but it may cause high-temperature corrosion.The higher the operation speed of the grate,the higher the oxygen concentration at the outlet of the first flue,and the incomplete fuel incineration;With the increase of fuel particle size,the rate of each stage of waste fuel incineration on the bed,the total mass loss of fuel and the flue gas temperature at the outlet of the first flue are reduced,and the more insufficient the incineration is;Too high or too low rear arch height may cause too high temperature of front and rear walls.The smaller the rear arch angle,the more uniform the gas mixing in the furnace.Within the scope of this study,the best working condition is that the grate running speed is 12.6m/h,the fuel particle size is25mm,the rear arch height remains unchanged,and the rear arch angle is 25°.This paper also makes a numerical simulation study on the possibility of mixed burning of dry waste,and analyzes the influence of mixed burning ratio of dry waste on in furnace incineration.The results show that with the increase of dry waste blending ratio,the reaction rate and total fuel mass loss at each stage on the grate increase,the outlet temperature of the first flue increases and the O₂concentration decreases.Properly increasing the mixing ratio of dry waste can promote the incineration of waste on the grate.