Rotary-type air pre-heater air leakage rate real-time estimation method based on differential pressure

Abstract

The invention provides a rotary-type air pre-heater air leakage rate real-time estimation method based on differential pressure. The method includes the steps that (1) related pressure, temperature and flow measuring point data of smoke of an air pre-heater and inlets and outlets of primary air and secondary air are read at a given moment from a real-time database of a DCS; (2) specific heat and density of the smoke and the inlets and the outlets of the primary air and the secondary air are calculated on the basis of an air physical property parameter library; (3) instant total air leakage quality flow is calculated according to energy balance of the smoke side and the air side, and an instant air leakage area is obtained and is stored in a stack mode; (4) the daily average air leakage area of the latest 24 hours is calculated at a fixed moment every day, and the average air leakage area is updated with the weighted average value of the daily average air leakage area of the latest days; (5) on the basis of the pressure difference and the average air leakage area, an instant total air leakage quality flow correction value and the air leakage rate are obtained. The method can be used for monitoring air leakage conditions of the air pre-heater on line, the maintenance cycle of the air pre-heater can be determined and tail smoke energy estimation can be corrected.

Description

technical field [0001] The present invention relates to a real-time estimation technology of the air leakage rate of an air preheater in the field of thermal power generation control, specifically, a real-time estimation technology of the air leakage rate of a rotary air preheater based on the pressure difference between the flue gas side and the air side. Estimation method. Background technique [0002] The high-temperature flue gas on the side of the thermal power plant boiler is still at a high temperature after heat transfer to the working medium through heat exchange equipment such as superheaters, reheaters, and economizers at all levels. In order to further utilize the waste heat energy of the flue gas, coal-saving Install an air preheater after the denitrification device to preheat the incoming air, and the preheated incoming air can also play the role of drying coal powder and stabilizing combustion. According to the different heat transfer methods, air preheaters ...

AI Technical Summary

Problems solved by technology

This method needs to measure a reference air leakage rate in advance to obtain the theoretical exhaust gas temperature, and can only obtain the air leakage rate under the same working condition, and cannot perform online real-time estimation

Images