Very long distance concentrated phase conveying process for coal fines

Abstract

The invention discloses a process for the over-length distance dense phase transport of coal dust, which is characterized in that: the pressure of a blowing can is between 1450KPa and 1650KPa, and the pressure of the gas acting on a fluidization plate is from 1250KPa to1330KPa; secondary gas supply is carried out concerning the coal dust transport pipe above 500m, secondary gas supply is also carried out between 400m and 500m of the coal dust transport pipe from the blowing can, and the pressure of the secondary gas supply is from 1250KPa to 1330KPa; the temperature of the heat preserving gas of the coal dust is from 170 DEG C to 200 DEG C, and the temperature of the coal dust is from 65 DEG C to 90 DEG C; the internal diameter of the coal dust transport pipe is from 55mm to 76.9mm. The transport process can greatly improve the coal dust blowing and transport capacity and simultaneously meet the needs of two or three blast furnaces; the transport process can completely replace coke with coal, and reduce the fuel cost, the operation cost and iron making cost of the furnaces; the transport process can also reduce the water carried into the furnaces by the coal dust, thereby saving fuel and reducing the iron making cost with remarkable economic benefit.

Description

technical field [0001] The invention relates to a pulverized coal dense-phase conveying technology for smelting blast furnaces, in particular to an ultra-long-distance pulverized coal dense-phase conveying technology. Background technique [0002] The pulverized coal used in smelting blast furnaces is usually transported into the blast furnace by means of coal injection conveying technology, while the dense phase conveying technology is widely used due to its advantages of large conveying capacity, high conveying efficiency, and enhanced smelting effect. The applicant has a set of device that adopts the German "one spray three" dense phase conveying technology, and uses a set of coal injection conveying device to spray coal simultaneously to three blast furnaces. However, in actual use, the applicant found that the farthest conveying distance of the above-mentioned device is within 500 meters (the design limit distance is 500 meters), which is not suitable for ultra-long-dis...

AI Technical Summary

Problems solved by technology

This process also has the disadvantages of small amount of pulverized coal transported per unit time, improper selection of process parameters, high moisture content of pulverized coal into the furnace, and unsuitable system.