Direct blowing type coal pulverizing system and method taking flue gas as drying medium

Abstract

The invention provides a direct blowing type coal pulverizing system and method taking flue gas as a drying medium. The structure is simple, arrangement is reasonable, the boiler flue gas is fully utilized, and the requirement of milling high-moisture coal can be met. The system comprises a coal pulverizing device and a flue gas extracting device; the coal pulverizing device comprises a coal feeder, a coal mill and a coarse pulverized coal separator which are sequentially connected; a pulverized coal outlet of the coarse pulverized coal separator is connected with a pulverized coal inlet of aboiler; a coal economizer is arranged in a flue of the boiler, and an induced draft fan is arranged at a flue outlet; and the flue gas extracting device comprises a high-temperature flue gas way connected with an inlet flue of the coal economizer, a middle-temperature flue gas way connected with an outlet flue of the coal economizer and a low-temperature flue gas way connected with an outlet flueof the induced draft fan, the three flue gas ways are connected to the mixed pipeline input end separately, the mixed pipeline output end is connected with the coal mill through a flue gas fan sequentially, and mixed flue gas is introduced to serve as a drying and explosion preventing medium.

Description

technical field [0001] The invention belongs to the technical field of coal-fired power generation, and specifically relates to a direct-blown pulverization system and method using furnace smoke as a drying medium. Background technique [0002] The pulverizing system is an important part of the combustion system of the pulverized coal boiler in the power station. Its main function is the preparation and transportation of pulverized coal, providing the boiler with a mixture of pulverized coal of qualified fineness and air powder at a suitable temperature. Pulverized coal boilers can be divided into lean coal anthracite boilers, bituminous coal boilers and lignite boilers according to the different properties of the fuel. The design and selection of the pulverizing system is carried out according to the different types of coal. Usually, a pulverizing system is only suitable for one type of coal. type of coal. [0003] Under the situation of complex changes in the coal market ...

AI Technical Summary

Problems solved by technology

[0003] Under the situation of complex changes in the coal market and frequent fluctuations in coal prices, the prices of lignite, lean coal, anthracite and bituminous coal often have large gaps and large fluctuations. Significantly affects coal procurement economics and fuel supply security for power plants

[0004] The traditional positive pressure direct blowing pulverizing system power plant boiler often has insufficient drying output of the pulverizing system when grinding high-moisture coal, which seriously affects the load capacity of the boiler

Images