Research On Coke Oven Flue Gas Nox Front-end Treatment And Heating Optimization Technology

At present,the ecological environment in China is becoming more and more serious.In the process of coking production,a large amount of nitrogen oxides are produced,which aggravates the environmental pollution.The nitrogen oxides in the flue gas of the coke oven are mainly produced in the vertical fire path,which has the greatest relationship with the gas combustion temperature in the fire channel,and the higher the combustion temperature,the more nitrogen oxides are produced.In this dissertation,the formation mechanism of nitrogen oxide is analyzed and its front-end treatment method is introduced,which mainly includes the optimal heating control of coke oven and the reduction of nitrogen oxide from the source.The thesis mainly introduces the detection and control system of the temperature of the vertical fire road and the flame temperature,and analyses the relation model of the gas flow and the temperature of the fire channel,the suction of the flue and the gas flow.On the basis of temperature control of coke oven,combined with fire falling management technology and single combustion chamber control technology,the optimization control of coke oven is carried out in many aspects,reducing the standard temperature of coke oven and reducing the emission of nitrogen oxide.The traditional PID algorithm can not meet the control requirements because of the characteristics of nonlinear and large time delay in the coke oven temperature system.This algorithm combines the advantages of fuzzy control algorithm and predictive control algorithm in this algorithm.The fuzzy predictive control algorithm is adopted in the control of coke oven temperature.The algorithm has been shown by MATLAB simulation that the algorithm has the advantages of the fuzzy control algorithm and the predictive control algorithm.It has many advantages such as good dynamic performance,small overshoot and strong anti-interference ability.Then it introduces the implementation process of the control scheme on SIEMENS PLC,and introduces the process of realizing the whole programming idea in detail.Through the analysis of the temperature curve before and after the operation of the system,the research shows that the control scheme is feasible and achieves the desired control effect.