RU1820150C - Method for preparing highly concentrated coal dust for combustion - Google Patents

Abstract

Use: for burning coal dust in steam boilers. SUMMARY OF THE INVENTION: streams of coal dust, hot air and swirling stream e are fed through the channels followed by their mixing, the drying agent being supplied in an amount of 0.15 ... 0.25 of the total consumption of hot air, and the aerosol is formed over a length-wise section. equal to 1 ... 3 diameters of the channel of the drying agent. 1 ill.

Description

The invention relates to solid fuel combustion technology and can be used in the power industry, mainly in steam boilers.

The aim of the invention is to improve the quality of combustion.

The drawing shows a device for implementing the proposed method.

The device comprises a pipe with a divider 1 for supplying highly concentrated coal dust, a channel of a drying agent 2, an annular swirler 3, a channel for mixing flows 4 and channels of hot air 5,

A method of preparing for the combustion of highly concentrated coal dust is as follows

Highly concentrated coal dust is directly fed through a pipe with a divider 1 and introduced into the flow mixing channel 4, which is cylindrical or conical in shape. The drying agent spent in the dust system is transported through channel 2 and, having received

using an adjustable ring swirler 3, the rotational movement is intensively mixed with coal dust in the channel 4. The hot air necessary to complete the combustion process of pulverized coal fuel is supplied to the furnace through channels 5.

The process of intensively mixing coal streams; dust and drying agent within the burner is ensured by the interaction of intersecting flows - swirling and flow-through, which is much more efficient than mixing two flow-through flows by jointly accelerating them. It has been found that for the formation of a uniform concentration of coal dust in the air mixture stream, the path from the start of mixing to discharge into the furnace is required, equal to (1-3) d, where d is the output diameter of the flow mixing channel. Adjustable depending on the quality of the fuel burned for: the twisting of the mixture flow creates conditions for the axial recirculation of high-temperature flue gases, which increases the level of C

with

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the efficiency of burning pulverized coal, Mixing with coal dust a low-temperature drying agent, which during the operation of the dust system is 0.15-0.25 of the total consumption of hot air, and the separate supply of hot air directly to the furnace makes the fuel combustion process stepwise, which reduces the formation of nitrogen oxides.

Thus, the proposed method will improve the efficiency of burning pulverized coal while reducing the content of nitrogen oxides in the flue gas.

Claims (1)

The claims The method of preparation for burning highly concentrated coal dust by supply through the respective channels of streams of coal dust, hot air and a swirling stream of drying agent with their subsequent mixing, characterized in that, in order to increase combustion quality, the drying agent is fed in an amount of 0.15 ... 0.25 of the total consumption of hot air, and the aerosol is formed in a section with a length equal to 1-3 diameters of the channel of the drying agent.