The Research On Optimization Of Process Monitoring And Control Method For Power Plant Flue Gas Denitrification

Economic growth led to the growing demand for electricity,China's power plants are still the main thermal power units.The nitrogen oxides produced by coal combustion are the main pollutants in the atmosphere and have serious environmental damage.Therefore,the increase of denitrification plant in power plants is the inevitable requirement of economic and social development.The denitration control system is the core of the denitrification system and is critical to the long-term stable operation of the equipment.In this paper,the first-stage denitrification system of Huaneng Dalian Power Plant is taken as the research object.Through the monitoring and analysis of the relevant parameters of the SCR process and the actual situation of the power plant,the control method of SCR flue gas denitrification is optimized.First of all,through the monitoring of the denitrification control process,the parameters related to the denitrification efficiency were analyzed,and the key parameters such as dilution air volume,ammonia ammonia flow rate and NOx production volume were selected to monitor the parameters.On this basis,Logic has been analyzed and optimized.Secondly,the main operating parameters of the boiler are designed as the design constraints.For the deviation of the flue gas from the coal and the coal,the correction coefficient is corrected in the logic,so that the calculation function of the amount of coal converted to the flue gas is more realistic Condition.Finally,the control logic of denitrification spray ammonia is optimized,and the theoretical spray flow rate of S-side input of PID regulator is optimized.The input parameters of NOx inlet and outlet NO_X concentration are optimized,and the optimized denitrification Adjust the control logic,so that the SCR system can be put into automatic operation.The optimized control logic is debugged and the denitrification performance of the unit under medium and high load conditions is tested.The results show that the optimization of denitration control logic makes the ammonia removal rate reach the better level by reducing the ammonia consumption and improves the denitrification efficiency by reducing the ammonia escape rate to meet the environmental assessment index.Optimized control logic can be adapted to different denitrification conditions,effectively reducing the operation of the operator.