Pyrolysis Process And Flow Field Analysis Of Straw Gasification Furnace

As the huge consumption of fossil energy required every year,many scientific research institutions began to explore the new alternate energy,and put forward the idea of biomass energy to replace fossil energy.Straw gasification technology can convert straw into combustible gas which instead of the daily use of fossil fuels.However,the current research and design of fixed bed gasifier still depends on the previous experience in many aspects.ICEM software was used for building a two-dimensional model of the gasifier and grid it.Based on the fluent module of ANSYS software,the working process in the gasifier was simulated.The random track model was used for tracking the movement of straw particles in Lagrangian coordinate system.Based on the P1 model,the radiation of heat transfer process,gasification process were simulated,and gasification characteristics of the straw gasifier were analyzed.Then the influencing factors of gasification performance of straw gasifier were analyzed.The simulation results showed that the maximum temperature,average temperature of the gasifier and gas content will be decreased with the increase of width of the chamber of a stove or furnace.However,If the Width of gasifier furnace is too small,the temperature in the hearth can lead to a gasifier reduce service life.When the particle size of straw reaches 40 mm,the temperature in gasifier drops rapidly,then the serious phenomenon of incomplete dry volatilization will happen.The maximum gasification efficiency occur when the air equivalent ratio is between 0.28 and 0.30.And when the air equivalent ratio is less than 0.28,the combustion of volatiles is incomplete and the furnace temperature is low due to the low O2 content.When the air equivalent ratio is greater than 0.30,the volatiles are completely burned with coke,but too much O2 will dilute the combustible gas.The water vapor/straw mass ratio will affect the gasification efficiency of gasifier.Moreover,the increase of water vapor/straw mass ratio will promote the reaction rate of coke and water gas,resulting in the decrease of the temperature in the gasifier and the increase of CO.Figure 38;Table 4;Reference 63...