Decoupling combustion furnace and decoupling combustion method

Abstract

The invention provides a decoupling combustion method, which comprises the following steps: a) firstly, performing pyrolysis and gasification of fuels to generate semicoke and gas; b) secondly, combusting part of gas and semicoke to perform oxidation reaction and reduction reaction to generate coke, and applying the generated heat to the pyrolysis and gasification in step a); c) thirdly, combusting the coke and the left gas generated in step a) under the condition that an excess air coefficient is less than 1, and simultaneously generating smoke in the combustion; and d) finally, performing full secondary combustion of the smoke and the remained gas after the steps. The decoupling combustion method can increase the decoupling combustion space and intensity with a smaller floor area; the increase of the gasification zone and the gasification intensity greatly improve the load increasing capability of a decoupling combustion furnace; and in addition, because the high-temperature smoke strongly heats the fuels in the upper part of a pyrolysis and gasification chamber and has higher pyrolysis and gasification intensity, the gas output is increased and the combustion amount of solid semicoke is reduced.

Description

technical field

[0001] The invention belongs to the field of raw coal combustion equipment, and in particular relates to a pyrolysis gasification decoupling combustion furnace with low nitrogen oxide emission and a decoupling combustion method. Background technique

[0002] In the practical application of fuel combustion, fly ash combustibles and CO are more likely to burn out quickly and fully with the increase of combustion temperature and excess air coefficient, but on the contrary they are not easy to burn out. At the same time, the lower the combustion temperature and excess air coefficient are, the more favorable it is for denitrification and sulfur fixation. The increase of combustion temperature and excess air coefficient will make the NO produced in the combustion process x It is greatly improved, and at the same time, the reverse reaction of the sulfur-fixing reaction is increased and the sulfur-fixing agent is "frozen", which is not conducive to sulfur-fixing. Th...

Examples

Embodiment Construction

[0026] Due to the existence of fuel nitrogen inherent in coal, the coal gas produced by pyrolysis gasification contains certain nitrogen-containing substances, including NH 3 , HCN, etc. If the pyrolysis gasification gas is burned in an oxidizing atmosphere, these nitrogen-containing substances will be converted into nitrogen oxides. If the pyrolysis gasification gas is used as the reburning gas, the nitrogen-containing substances will x The reduction plays a promoting role. If the coal gas produced in the pyrolysis gasification chamber in the decoupling combustion furnace enters the semi-coke combustion zone, an appropriate amount of air is added to the appropriate position for premixing, so that the mixed gas can be burned under the condition that the excess air coefficient is less than 1, so that the main combustion NO produced in an oxidizing atmosphere x Reduction, the combusted mixed gas is mixed with the incoming secondary air and burned up, so that the emission of ni...

technical field

[0001] The invention belongs to the field of raw coal combustion equipment, and in particular relates to a pyrolysis gasification decoupling combustion furnace with low nitrogen oxide emission and a decoupling combustion method. Background technique

[0002] In the practical application of fuel combustion, fly ash combustibles and CO are more likely to burn out quickly and fully with the increase of combustion temperature and excess air coefficient, but on the contrary they are not easy to burn out. At the same time, the lower the combustion temperature and excess air coefficient are, the more favorable it is for denitrification and sulfur fixation. The increase of combustion temperature and excess air coefficient will make the NO produced in the combustion process x It is greatly improved, and at the same time, the reverse reaction of the sulfur-fixing reaction is increased and the sulfur-fixing agent is "frozen", which is not conducive to sulfur-fixing. Th...

Examples

Embodiment Construction

[0026] Due to the existence of fuel nitrogen inherent in coal, the coal gas produced by pyrolysis gasification contains certain nitrogen-containing substances, including NH 3 , HCN, etc. If the pyrolysis gasification gas is burned in an oxidizing atmosphere, these nitrogen-containing substances will be converted into nitrogen oxides. If the pyrolysis gasification gas is used as the reburning gas, the nitrogen-containing substances will x The reduction plays a promoting role. If the coal gas produced in the pyrolysis gasification chamber in the decoupling combustion furnace enters the semi-coke combustion zone, an appropriate amount of air is added to the appropriate position for premixing, so that the mixed gas can be burned under the condition that the excess air coefficient is less than 1, so that the main combustion NO produced in an oxidizing atmosphere x Reduction, the combusted mixed gas is mixed with the incoming secondary air and burned up, so that the emission of ni...

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