Device for recycling boiler tail smoke heat

Abstract

The invention discloses a device for recycling boiler tail smoke heat. The device is arranged on a smoke pipeline between a boiler economizer and dust removal equipment. The device for recycling the boiler tail smoke heat comprises a compound phase-change heat exchanger and a self-control device. The self-control device is electrically connected with the compound phase-change heat exchanger. The compound phase-change heat exchanger is provided with a first wall temperature tester, the first wall temperature tester is used for measuring the temperature of a heat absorbing section heated face of the compound phase-change heat exchanger and controlling the temperature of the heat absorbing section heated face of the compound phase-change heat exchanger to be always higher than the temperature of a fire coal acid dew point through the self-control device. An evaporation section of the compound phase-change heat exchanger is used for utilizing the boiler tail smoke heat to heat air entering a boiler and heat demineralized water. The self-control device is used for data collection control over the compound phase-change heat exchanger and is composed of a temperature sensor, a control device, an executor and a flow meter, and the temperature sensor, the executor and the flow meter are all connected with the control system.

Description

technical field [0001] The invention belongs to the technical field of flue gas recycling and reuse, and particularly relates to a device for recycling the heat of flue gas at the tail of a boiler. Background technique [0002] At present, in the industries that use boilers in my country, because coal, oil, natural gas and other fuels contain sulfur, sulfur oxides are usually produced during combustion, and sulfur oxides are combined with water vapor to form sulfuric acid steam; when the heating surface of the boiler tail is heated. The temperature of the metal wall surface is lower than the condensation point of sulfuric acid vapor (called acid dew point), and liquid sulfuric acid (called condensation) will be formed on its surface. [0003] At present, the corrosion caused by condensation on the rear heating surface of the air preheater often occurs and is unavoidable, so that the current boiler design has to increase the exhaust gas temperature or use non-metallic material...

AI Technical Summary

Problems solved by technology

[0006] The invention proposes a device for recovering and utilizing the heat of flue gas at the tail of the boiler, which solves the defects of the prior art that the air preheater is easy to corrode and the waste of a large amount of low-temperature energy is caused by simply increasing the exhaust gas temperature

Images