Soft Sensing Method of SO_2 Emission from Power Plant Based on Variable Compression BP Neural Network

Abstract

The invention relates to a soft sensing method for SO2 emission of a power plant based on variable compression BP neural network, comprising the steps of S1, collecting sample data about time variation in a wet flue gas desulfurization system, and determining neurons of an input layer and an output layer of the dynamic neural network according to the collected sample data; 2, performing correlation analysis on that sample data, compressing the original sample variable to remove sample data whose correlation with SO2 in the flue gas at the outlet of the wet flue gas desulfurization system is less than 0.2; Step S3: Compressing by using the variable-BP neural network model wet flue gas desulfurization system, establish wet flue gas desulfurization system prediction model; Step S4, calculating the predicted value of SO2 concentration at the flue gas outlet of the wet flue gas desulfurization system by using the wet flue gas desulfurization prediction model established in the step S3; StepS5: controlling The slurry spraying amount of the wet flue gas desulfurization system by using the predicted value of step S4.

Description

technical field [0001] The invention belongs to the technical field of flue gas desulfurization prediction control technology in thermal power plants, and in particular relates to a power plant SO2 based on variable compression BP neural network. 2 Emission soft measurement method. Background technique [0002] Limestone-gypsum wet flue gas desulfurization technology is to add limestone powder and water to make a slurry as an absorbent and pump it into the absorption tower to fully contact and mix with the flue gas. The sulfur dioxide in the flue gas, the calcium carbonate in the slurry and the air blown from the lower part of the tower The oxidation reaction produces calcium sulfate, and when the calcium sulfate reaches a certain degree of saturation, it crystallizes to form dihydrate gypsum. [0003] The gypsum slurry discharged from the absorption tower is concentrated and dehydrated to make its water content less than 10%, and then sent to the gypsum storage warehouse b...

AI Technical Summary

Problems solved by technology

When the load of the unit is in a steady state, a better control effect can be obtained, but under variable operating conditions, the system presents nonlinearity and large hysteresis. At this time, it is difficult to better control the flow rate of the slurry in the spray tower

If the amount of slurry sprayed is too small, it will be difficult to ensure that the emission standard of flue gas can be met; if the amount of slurry sprayed is too much, it will cause waste of resources

Therefore, conventional control methods are difficult to achieve timely control and achieve ideal smoke emission effects

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