Power station boiler system and method for increasing tail fume temperature of power station boiler by integrating supplemental combustion for biomass gasification

Abstract

The invention discloses a power station boiler system and a method for increasing the tail fume temperature of a power station boiler by integrating supplemental combustion for biomass gasification. According to the method, one or more fixed bed biomass gasifiers are additionally arranged, the gasifiers maintain the rated loads to continuously and stably operate, and hot primary air of the boiler is used as a gasification agent to promote the gasification efficiency of the gasifiers and increase the heat value of gasified gas; when the boiler operates with the low load, the biomass gasified gas is delivered into a flue behind a coal economizer or a steering fume chamber in front of the coal economizer, and the fume temperature at an outlet of the coal economizer is increased through supplemental combustion of the biomass gasified gas, so that a selective catalytic reduction fume denitration system operates safely and stably; supplemental-combustion gas is reduced correspondingly along with increasing of the loads, and the reduced gasification gas for supplemental combustion is delivered into the upper portion of a hearth so as to be combusted, and when the boiler operates with the full load, all the biomass gasified gas is delivered into the upper portion of the hearth so as to be combusted; and supplemental-combustion temperature increasing of the tail fume of the power station boiler is finally achieved through biomass resources, and meanwhile, the biomass resources can be further efficiently used for power generation.

Description

technical field [0001] The invention belongs to the technical field of supplementary combustion and heating of flue gas at the tail of power plant boilers, and in particular relates to supplementary combustion and heating of flue gas at the tail of power plant boilers by using gasification gas generated from biomass such as straw and rice straw, so as to ensure selective catalytic reduction of flue gas denitrification The method of safe operation of the system. Background technique [0002] When the boiler is operating at low load, the flue temperature at the outlet of the economizer is often lower than the catalytic reaction temperature window of 320-420°C for the selective catalytic reduction flue gas denitrification system, which will cause the selective catalytic reduction flue gas denitrification system to fail to operate normally. The increasingly stringent emission standards make the continuous and stable operation of the flue gas denitrification system an inevitable ...

AI Technical Summary

Problems solved by technology

However, for a long time, the utilization of biomass energy in my country has been dominated by direct combustion, which not only has low thermal efficiency but also produces a large amount of smoke and dust, causing serious damage to the environment.

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