ResearcResearch On Energy-Saving Of Fans And Nitrogen Oxides Emission Reduction In Thermal Power Boiler

Thermal power plants in China are both the major producer of electricity and the major consumer of coal resources. Coal-fired power plants pour a large volume of pollutants to the atmosphere, for example, nitrogen oxides while generating energy. It shows that the power consumption of fans in thermal power plant accounts for 70 percent of the power consumption of the whole thermal power plant. And some primary energy sources like coal are wasted in this process. Therefore, the energy-saving potential of the fans is big. Energy-saving and emission reduction in thermal power plants have come to be the most important objectives of energy policies in our country.In this paper, a relatively high-quality robust predictive PID control scheme based on the theory of multi-model is proposed in detail. A PID controller based on generalized predictive control algorithm is designed at first. Second, multi-model predictive PID control strategy is established based on gain scheduling with introducing of multi-model thought. At last, considering the closed-loop robust stability of the control system, the robust predictive PID controller based on the theory of multi-model is designed successfully. The control strategy taking into account the advantages of both PID control and GPC control can improve the quality of some important control loops in thermal power plant, and the simulation results show that the control scheme has a good control performance.In this paper, the types of the important fans in thermal power plant and the main energy-saving approaches are analyzed and summarized first. And a new method of calculating the set point of oxygen of flue gas is proposed based on the combustion optimization by analyzing the influencing factors, taking the lowest coal consumption as the goal, using the linear regression method, and the optimized set point of oxygen is calculated. At last, the energy-saving program is proposed combining with the robust predictive PID control scheme.In this paper, the formation mechanism of nitrogen oxides in thermal power plant and the main measures of nitrogen oxides emission reduction are described in detail. And a forecast formula of nitrogen oxides is proposed with the method of multiple linear regression. Base on this mathematical model, the nitrogen oxides emission reduction programs is proposed at last.