Research And Application Of Wet Flue Gas Desulfurization Control System In Thermal Power Plant

With people’s consciousness of environment protection increasing constantly,the research of flue gas desulphurization technology in coal-combustion power plant is receiving much more attention.In numerous flue gas desulphurization technology,flue gas desulphurization in limestone-gypsum wet method is used a lot because of many advantages.In the process of this technology,the value of the absorber slurry pH is the most important factor to affect desulfurization rate,utilization rate of lime stones and end product gypsum quality.In conclusion,the research of improving the absorber slurry pH value control precision is critical.Flue gas desulphurization process has characteristics of time-varing,large inertia,lagging and nonlinearity,etc.In order to overcome disadvantages of the traditional PID control algorithm and manual operation,the RBF-PID controller which is used in three parameters setting of PID online is presented in this study.The comparative study of MATLAB simulation shows that RBF-PID algorithm has advantages of less overshoot,shorter adjustment time,stronger robustness and anti-interference ability,etc.It enhances the system real-time operating effect and solves the problem of low control precision caused by difficult parameter setting and poor adaptive ability of traditional PID algorithm.The study also adopts a neural network internal model controller and does the MATLAB simulation study to remedy the lag system problem which RBF-PID controller does not slove.The simulation study shows that the controller is better than RBF-PID algorithm,Smith prediction PID control algorithm and traditional PID algorithm in the control effect.It not only improves the control precision of the absorber slurry pH value,but also overcomes control difficulties caused by time delay.At last,the MCGS configuration software is adopted to complete the monitoring system of wet coal-fired power plant flue gas desulfurization process.The data communication between the MCGS and MATLAB7.11 was realized by OPC technology to implement the control algorithm.Finally the feasibility of the design for the absorber slurry pH value control in the flue gas desulphurization process is validated through the simulation.