Positive-pressure direct-firing pulverizing system based on segmented temperature control and control method thereof

Abstract

The invention discloses a positive-pressure direct-firing pulverizing system based on segmented temperature control and a control method of the positive-pressure direct-firing pulverizing system. The positive-pressure direct-firing pulverizing system comprises an air preheater, an air feeder, a primary air fan, a seal air fan, a coal mill, a tailing separator, a raw coal hopper, a coal feeder, a pulverized coal distributor, an isolation door, a pulverized coal feeding system adjustment bellows, a pulverized coal burner and a secondary bellows. According to the control method, an inlet and an outlet of the coal mill are taken as a segment, an inlet and an outlet of a pulverized coal feeding system are taken as another segment, cold air and hot air are fed into the corresponding inlets of the two segments through corresponding pipelines, the temperatures of the two segments are monitored respectively, and then segmented control over the temperature of the pulverizing system is achieved. By means of the control method, the temperature of the pulverizing system and the temperature of the pulverized coal feeding system can be independently controlled, the air speed of the pulverized coal feeding system is kept not decreased under the condition that the air quantity of the pulverizing system is changed, and the demands for conveying pulverized coal and preventing a nozzle from being burnt out are met.

Description

【Technical field】 [0001] The invention belongs to the technical field of coal-fired power generation, and in particular relates to a positive pressure direct-blowing pulverizing system based on temperature segment control and a control method thereof. 【Background technique】 [0002] For traditional positive pressure direct blowing pulverizing system power plant boilers, the hot air entering the pulverizing system dries the pulverized coal in the pulverizer, and then sends the pulverized coal into the furnace through the pulverizing pipeline for combustion. The ventilation volume of the pulverizing system is the same as that of the powder feeding system, and the outlet temperature of the pulverizing system is the same as that of the powder feeding system. When the volatile matter, moisture, and boiler load of the actual coal entering the boiler change greatly, the ventilation volume of the pulverizing system and the outlet air temperature of the pulverizing system are require...

AI Technical Summary

Problems solved by technology

To meet the air temperature and air volume requirements of the pulverizing and powder feeding systems at the same time, it is often necessary to mix the pulverizing system with cold air, sacrificing the economy of boiler operation

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