Secondary air system for waste incineration boiler and secondary air operation method

Abstract

The invention discloses a secondary air system for a waste incineration boiler, and belongs to the technical field of combustion equipment and combustion manners. The secondary air system comprises the boiler, a smoke recirculating pipe, a cold air pipe, a secondary air main pipe, a secondary draught fan, a front secondary air pipe, a rear upper secondary air pipe and a rear lower secondary air pipe. The smoke recirculating pipe is arranged at an outlet of the boiler; one end of the secondary air main pipe is connected with the smoke recirculating pipe and the cold air pipe, and the other end of the secondary air main pipe is connected with the front secondary air pipe, the rear upper secondary air pipe and the rear lower secondary air pipe; and the secondary draught fan is arranged on the secondary air main pipe. Cold air or smoke can be independently used in secondary air in the system, the cold air and the smoke can also be used at the same time according to a certain proportion, the smoke and air mixing condition in a hearth can be better improved, and the oxygen concentration of a hearth area is controlled. After the secondary air system is adopted for the boiler, the emission of NOx in the smoke can be reduced by about 30%, and the secondary air system has the beneficial effects of being simple in structure, convenient to install and maintain, free of operation cost and the like.

Description

technical field [0001] The invention belongs to the technical field of combustion equipment and combustion methods, and in particular relates to a secondary air system for a waste incineration boiler and a secondary air operation method. Background technique [0002] Fuel combustion is prone to produce nitrogen oxides NO x . Nitrogen oxide NO x It is not only one of the main substances that form acid rain and acid fog, but also participates in the formation of photochemical smog and the destruction of the ozone layer. It is highly toxic to humans, animals and ecology. [0003] To reduce NO in the flue gas x Domestic waste power plants mainly adopt boiler low-oxygen combustion technology, selective non-catalytic reduction SNCR and selective catalytic reduction SCR denitrification processes. [0004] SNCR has low fixed investment, simple equipment, and low operating costs, but the denitrification efficiency is not high, and ammonia escapes more, which may cause secondary p...

AI Technical Summary

Problems solved by technology

[0004] SNCR has low fixed investment, simple equipment, and low operating costs, but the denitrification efficiency is not high, and ammonia escapes more, which may cause secondary pollution

Although SCR has high denitrification efficiency and can meet stricter emission standards, it has large fixed investment, complicated equipment and high operating costs.

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