Low-load burner capable of achieving boiler flue heat recycling for boiler

Abstract

The invention discloses a low-load burner capable of achieving boiler flue heat recycling for a boiler. The low-load burner capable of achieving boiler flue heat recycling for the boiler comprises a front-end wind-powder pipeline, a coal pyrolysis chamber, a coal pyrolysis gas nozzle, a smoke guiding pipeline, a Laval nozzle, and an air supply duct, wherein the front end of the air supply duct is communicated with an inlet end of the coal pyrolysis chamber, and is connected with the wind-powder pipeline in parallel and jointes at the inlet end of the coal pyrolysis chamber, the rear end of the air supply pipeline is communicated with the front end of the Laval nozzle, the rear end of the Laval nozzle is used for connecting an air feeder, the Laval nozzle is arranged in a transverse mode, the smoke guiding pipeline is a bent pipe arranged in a vertical mode, the upper end of the smoke guiding pipeline is used for communicating with a horizontal boiler flue and the lower end of the smoke guiding pipeline is communicated with the throat portion of the Laval nozzle, and high temperature flue gas in the horizontal boiler flue is guided into the coal pyrolysis chamber through the smoke guiding pipeline to provide a heat source for coal powder pyrolysis. The low-load burner capable of achieving boiler flue heat recycling for the boiler is simple in structure and capable of achieving low-load stable operation of an adjusting peak set, and operation efficiency and safety of the set are improved.

Description

technical field [0001] The invention relates to an auxiliary equipment of a boiler in a power plant, in particular to a boiler low-load burner for reusing boiler flue heat. Background technique [0002] The operation of coal-fired power stations is relatively common in my country, and there are relatively mature technologies. However, the cost of fuel injection and combustion support when the unit is under low load is still a major problem affecting power generation companies to improve production efficiency. Boiler oil injection mostly occurs in the following working conditions: 1. When the low load of the peaking unit is close to 50% load or below, due to the low concentration of pulverized coal in the primary air, the low temperature of the furnace, and the unreasonable ratio of primary and secondary air, resulting in combustion unstable. 2. When the coal type deteriorates, it is difficult to adjust the air-powder ratio. In order to stabilize the combustion in the furna...

AI Technical Summary

Problems solved by technology

However, the cost of fuel injection and combustion support when the unit is under low load is still a major problem affecting power generation companies to improve production efficiency

Boiler oil injection mostly occurs in the following working conditions: 1. When the low load of the peaking unit is close to 50% load or below, due to the low concentration of pulverized coal in the primary air, the low temperature of the furnace, and the unreasonable ratio of primary and secondary air, resulting in combustion unstable

2. When the coal type deteriorates, it is difficult to adjust the air-powder ratio. In order to stabilize the combustion in the furnace, oil is sometimes added to stabilize the combustion.

3. During the cold and hot start-up process of the boiler, the oil system generally has to be put into operation

[0003] It is an effective method to use pyrolysis gas produced by coal pyrolysis to support combustion and replace part of the oil input. However, if an additional new gas generation system is installed in the existing power station, the cost is high, the investment is relatively large, and the economic benefit is not high.

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