Optimization Of Coal Loading And Leveling Process In Coke Oven Based On The Simulation With Discrete Element Method

With the rapid development of the domestic coking industry,increasing the coal charging quantity of a single hole of coke ovens has become a research focus within limits of equipment capability.However,the carbonization chamber used for coal loading is like a "black box",in which the changes in blanking and the impact on coal peaks during coal leveling are difficult to judge,and traditional physical experiment research has great uncertainty.Therefore,a simulation model is established based on the discrete element method in this paper.The accumulation process of coal particles and the process of coal loading in a carbonization chamber are studied,and the macroscopic phenomena and micromechanics are discussed.The main research contents and conclusions of this article are as follows:1)The fixed hopper method was used to measure the coal repose angle,and the average coal repose angle was 31.63°.The results of orthogonal experiments show that the coal repose angle was linearly and negatively related to the funnel installation height,while here was no significant correlation with the diameter of the discharge port and the diameter of the circular plate.Meanwhile,we carried out discrete element simulation for the stacking experiment under the same experimental conditions.The average value of the simulated repose angle was 31.82°,and the average error was 2.23%compared with the experimental value.This shows that the discrete element simulation can correctly describe the coal particle stacking process.2)The discrete element simulation was used to study the influence of the discharge height and the contact parameters of coal particles on the repose angle.The simulation results show that the higher the discharge height,the smaller the coal repose angle,and which also be explained from the perspective of micro mechanics;Besides,the factor experiment was used to analyze the influence of the particle contact parameters on the repose angle.The research shows that the static friction factor and rolling friction factor of the coal particles have a significant effect on the repose angle,while the recovery coefficient has little effect on the repose angle.3)A simulation model of the carbonization chamber was established and the process of coal loading and leveling was simulated and optimized from the three operating variables of coal loading sequence,coal loading per unit time and number of flat coals.It is found that when the coal drop ports near the coke side and the machine side first drop coal,the coal can provide support for gaps on both sides;Under the condition that the coal loading process is without blocking and the dust removal effect is high,the larger the coal loading amount,the better the coal loading effect;As for the coal leveling process,the combination of long flat coal and short flat coal can be used to compact and homogenize the coal material in the carbonization chamber and significantly improve the coke side gap problem.Therefore,the method of coal loading and leveling for 6.98 m coke oven is as follows:1#,4#port first coal loading,with a single port coal load of 69.02 kg/s,using two long flat coal and two short flat coal,the final total coal charging quantity is 42.81 t,which is 1.11t higher than the designed value.