Method for improving boiler combustion economy of tangential combustion anthracite coal boiler

Abstract

The invention discloses a method for improving the boiler combustion economy of a tangential combustion anthracite coal boiler. The combustors of the coal-fired boiler comprise a main combustor and an upper tertiary air combustor, wherein the main combustor is positioned in a main combustion region in a coal-fired boiler body, and the upper tertiary air combustor is next to the upper part of the main combustion region. The method comprises the following steps: (1) adding a layer of tertiary air jet nozzle below secondary air of the lowermost layer of the main combustion region to serve as a lower tertiary air combustor; (2) forming openings in original tertiary air pipes on the four corners of the boiler, and guiding original tertiary air to the added tertiary air jet nozzle by an added pipeline so as to increase the burn-off rate of coal powder without influence of low-load stable combustion capability of the boiler. According to the method, the boiler efficiency can be improved by more than 3% on the basis of guaranteeing the stable combustion capability of the boiler; the efficiency of the anthracite coal boiler is greatly improved, and the combustion stability of the boiler cannot be influenced; by the method provided by the invention, the investment and the running expense are low and the national conditions of China are met.

Description

【Technical field】 [0001] The invention belongs to the technical field of boiler combustion, and in particular relates to a method for improving boiler combustion economy for tangentially burning anthracite boilers, which is suitable for boilers burning low-quality anthracite coal. 【Background technique】 [0002] Anthracite is the coal with the deepest degree of coalification. The volatile content of dry ash-free base is generally below 10%. It is characterized by low ash and moisture, high calorific value, up to 25000-32500kJ / kg, and high volatile content release temperature. It is difficult to ignite and burn out, and it has no smoke when burning, and the flame is blue. Anthracite occupies a considerable proportion of power coal used in power station boilers in my country, and its production areas are mainly located in Shanxi, Guizhou, Yunnan and Hunan. When using the tangential combustion method on the power plant boiler, in order to avoid the negative effects caused by i...

AI Technical Summary

Problems solved by technology

[0003] In recent years, with the increase of thermal power installed capacity in my country and the change of coal supply situation, power plants are increasingly unable to purchase coal similar to the design coal in time, and have to burn a large amount of anthracite coal with high ash content and low calorific value, resulting in boiler efficiency. The load capacity of boilers and boilers has dropped significantly, which has seriously affected the operating economy of thermal power units.

It is understood that the boiler efficiency of many anthracite coal power plants has dropped below 85%, which not only causes a sharp increase in coal consumption for power generation, but also causes serious waste of resources

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