Cyclone burning method and device for reburning fuel in cyclone drum for denitration

Abstract

The invention discloses a cyclone reburning method and device for reburning fuel in a cyclone drum for denitration. The device comprises a cyclone drum, a boiler main hearth and a granulating water tank, wherein the cyclone drum and the boiler main hearth are connected seamlessly through a concave outlet of the cyclone drum, overfire air nozzles are distributed at the upper part of the boiler main hearth, and the granulating water tank used for granulating liquid slag is arranged at the bottom of the boiler main hearth. In the invention, since reburning denitration is realized in the cyclone drum, reburnt fuel can stay in a boiler for a longer time; meanwhile, the upper part of the boiler main hearth at the rear part of the boiler has enough space for the distribution of the overfire air nozzles; therefore, the problem that the normal operation of a cyclone furnace boiler is threatened when a conventional reburning technology is adopted is solved very well, and the problems of the reburning technology per se, such as low burn-off rate of reburnt fuel and high smoke temperature of a hearth outlet and the like, can be overcome very well. The method disclosed in the invention not only has high denitration rate, but also uses simple equipment, is convenient and easy to implement, has low cost, is easy in the reformation of a traditional boiler, has remarkable social benefit and can be promoted and applied widely.

Description

Technical field: [0001] The invention relates to a method for reducing pollutant NO in the combustion process of a cyclone furnace x Generated combustion method and device thereof. Background technique: [0002] The cyclone furnace refers to a steam boiler for power that adopts the cyclone combustion method. When the air drives the pulverized coal particles to rotate and burn in the cylinder, it is called cyclone combustion. Cyclone combustion is a stable and controllable high-speed rotating flame flow artificially organized. It fills the entire combustion chamber space and has an extremely strong disturbance ability. , It has a higher heat intensity than the general chamber combustion method. The main combustion cylinder in the cyclone furnace is called the cyclone cylinder. A cyclone furnace can have one or several cyclones. Due to the high combustion temperature (temperature above 1650°C) and extremely strong mixing intensity in the cyclone, a large amount of air poll...

AI Technical Summary

Problems solved by technology

[0004] When the reburning technology is applied to the cyclone furnace, if the design is carried out according to the conventional reburning technology idea, that is, the cyclone is used as the main combustion zone, and the reburning zone and the burnout zone are arranged at a certain position along the height of the main furnace behind the furnace, it is bound to be possible It will have a relatively large negative impact, and even pose a threat to the normal operation of the cyclone furnace in severe cases

The main reason is: the cyclone furnace is a boiler with liquid slag discharge method. Compared with the normal combustion method, when the conventional reburning technology is adopted, the total heat release in the cyclone is reduced due to the reduction of the amount of fuel fed into the cyclone. , thus reducing the temperature inside the cyclone, which may pose a threat to maintaining normal liquid slag discharge

Therefore, when the reburning technology is used, the degree of fuel classification is limited, that is, the fuel feeding rate of the main combustion zone in the cyclone should not be too low compared with the normal combustion condition (for example, only about 90%), and the biggest negative impact is to make Final NO x The degree of reduction is small, so that the fuel reburning technology has the ability to reduce NO in the combustion process x The ability to generate is not fully utilized

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