Humidification and desulfurization purging device for tail flue of coal-fired boiler

Abstract

The invention discloses a humidification desulphurization sweeping device for a tail flue of a coal-fired boiler, and belongs to the technical field of coal-fired boiler desulphurization. The humidification desulphurization sweeping device is matched with a flue gas humidification activation or calcium-adding desulphurization technical device for the tail flue of the coal-fired boiler; damp falling ash generated by a flue gas humidification desulphurization technology are effectively removed under certain temperature and pressure through flue gas generated by the coal-fired boiler, and blocking caused by a fact that the falling ash is attached to the flue is prevented. The sweeping device is mounted in a space formed among a coal-fired boiler economizer, an air preheater and a dust remover and mainly comprises a gas conveying pipeline, a cyclone separator, a draught fan, a flue gas connection box and a gas outlet connection pipe. Part of the ash-containing flue gas is discharged from the flue at the outlet of the air preheater and the flue at the outlet of the economizer; due to separation of the cyclone separator, most of the ash is removed; then the flue gas enters the flue gas connection box and then enters the tail flue through the gas outlet connection for tail flue sweeping. The humidification desulphurization sweeping device is simple in structure and smaller in investment; the problem of scaling caused during desulphurization running is reduced, and the humidification desulphurization efficiency at the tail part is improved.

Description

technical field [0001] The invention relates to a humidifying desulfurization purging device for a tail flue of a coal-fired boiler, belonging to the technical field of desulfurization of a coal-fired boiler. Background technique [0002] In order to remove sulfur dioxide in the exhaust gas of coal-fired boilers, many processes have been developed. The more common desulfurization processes are wet, dry and semi-dry flue gas calcium desulfurization technologies. Coal mixed with desulfurization agent or calcium spraying desulfurization in the furnace, etc. In the case of calcium spray desulfurization in the circulating fluidized bed boiler furnace, the amount of limestone generally needs to reach a calcium-sulfur ratio of 2.0-2.4, and most of the incompletely reacted calcium oxide will be released with the fly ash in the flue gas. In addition, factors such as circulation ratio, combustion temperature, fluidization wind speed, and limestone particle size and properties will al...

AI Technical Summary

Problems solved by technology

However, in recent years, the semi-humidification and desulfurization method of the tail flue of coal-fired boilers has affected its application and development due to its own shortcomings. The ash in the gas condenses to produce wet ash and adheres to the bottom of the flue, causing accumulation, which in turn blocks the flue, increases the resistance and energy consumption of the flue gas discharge, and increases the difficulty of equipment operation and operation

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