Simulation And Optimization Of Denitrification Internal Components In Activated Coke Flue Gas Purification Reactor

In this thesis,we take the activated coke flue gas purification reactor from a coking plant as a sample,and use the numerical simulation method to build model and verified it,based on this,analyze the flow distribution inside the reactor.In order to improve the denitration efficiency of the system,aiming at the uneven distribution of flue gas in the reactor air chamber and the uneven distribution of ammonia concentration in the denitration section,the scheme of adding guide plate at the flue gas inlet chamber and setting eddy components in the ammonia injection area is proposed.The size and layout of the reactor internal components are optimized by computer simulation,and the following conclusions are drawn:(1)Build a numerical calculation model of the activated coke flue gas purification reactor.The results between the actual pressure drop of the system and the simulation results under different working conditions is 4.7%,which demonstrates the model is reliable.It can be seen from the trace diagram of flue gas in the original reactor and the cloud diagram of flue gas velocity distribution in the coke layer that,due to the influence of the reactor structure,flue gas flows into the gas chamber and then sticks to the wall,forming a eddy.The flue gas velocity distribution in the coke layer is quite different,which has a negative impact on flue gas purification.(2)Combined guide plate was added on the basis of previous studies.The flow field in the reactor with different length of straight plate,radius of circular plate and space between plates was simulated.It is found with comparison that the best uniformity of flue gas in the reactor is obtained when using 3.5m long straight plate,4 arc plates with the same radius(R= 0.8m)and the same plate spacing(d = 1.2m).In this scheme,the standard deviation of flue gas velocity distribution is 12% lower than that of the original reactor.(3)The eddy component is added for ammonia injection.The orthogonal analysis and simulation calculation are carried out for the layout scheme of the opening diameter(80mm,110 mm,140mm)of ammonia injection pipe and the inclination angle(15 °,45 °,75 °)of eddy plate.According to the simulation results,when the diameter of ammonia injection pipe is 80 mm and the scroll plate is inclined 45 °,the ammonia injection effect is the best,and the The relative standard deviation of the ammonia concentration distribution in the calculation domain decreased from 71.24% to 19.63%.(4)The laboratory simulationsmoke was determined by changing the experimental conditions such as flue gas residence time and system reaction temperature.The denitration efficiency under different temperature conditions was simulated on the basis of the original reactor model.The error between the simulation results and the actual results was less than10%.Based on this,the optimization results of eddy current components and deflectors are integrated,and the denitration efficiency of the optimized system is increased from 82% of the original reactor to 91.75%.