Coking coal blending method

Abstract

The invention discloses a coking coal blending method. The method comprises the following steps: 1) controlling the quality of major coking coal; 2) selecting strong fat coal; 3) matching the coals for use. According to the method, the wear resistance M10 of the coke of the small coke oven is taken as a control index, the coal type ratio is adjusted by controlling the quality of the 1# major coking coal and the 2# major coking coal and distinguishing strong fat coal, and under the condition that the total ratio of the major coking coal in a coal blending structure is less than 40%; in addition, under the process conditions of no graded crushing, coal briquette process or tamping coking and the like, the the abrasion resistance M10 of coke smelted by the full-dry quenching coke oven is smaller than 6.5% (4.3 m high, 6 m top load).

Description

technical field [0001] The invention belongs to the technical field of metallurgical coking coal blending, and in particular relates to a coking coal blending method in which a low main coking coal blending structure controls coke wear resistance strength. [0002] technical background [0003] Coke is one of the important raw materials for blast furnace ironmaking. With the enlargement of the blast furnace and the increase of the amount of coal injected, the requirements for coke quality indicators are getting higher and higher. Coke quality indicators include chemical work points (Ad%, St, d%, Vdaf%), cold strength (M40%, M10%), thermal properties (CRI%, CSR%) and lumpiness, among which the cold strength index M10% That is, the wear resistance of coke. The definition of coke wear resistance is: when the friction force on the outer surface of coke exceeds the strength of the pore wall, the phenomenon of surface thin layer separation occurs, forming debris and powder, and t...

AI Technical Summary

Problems solved by technology

[0006] 1) Improve coke wear resistance M10 by increasing the proportion of main coking coal and reducing the proportion of 1 / 3 coking coal and lean coal. The disadvantage of this method is not only to increase the cost of coal blending, but also the quality of main coking coal is complex and mixed, sometimes it cannot be improved M10;

[0007] 2) Improve the coke wear resistance M10 by increasing the proportion of strong fat coal and reducing the proportion of coking coal and lean coal by 1 / 3. The disadvantage of this method is also to increase the cost of coal blending. The increase in the proportion of strong fat coal will also lead to coke M40 index Get worse and lose sight of the other;

[0008] 3) By prolonging the coking time and increasing the standard temperature, the M10 index of coke wear resistance can be improved to a certain extent. The shortcomings of this method have been shown to be insignificant, and it will reduce coke production and increase gas consumption.

[0009] 4) CN 104678075 "Prediction method of coke abrasion resistance strength for coal blending" needs to measure coal ash composition mineral index MCI, single coal coking optical structure, blending coal reflectance Rmax≥1.65% lean coal blending ratio etc. to predict and control the wear resistance of coke. This method requires many indicators and complex calculations, and it is difficult to implement in general coking plants lacking relevant technologies.

[0010] 5) CN 104845650 "Coking Coal Blending Method for Controlling Coke M10 Index", this method refers to when the gas-coal ratio reaches 10% to 15%, by controlling the proportion of gas-rich coal and high-volatile fat coal in the coal blending structure To control the wear resistance of coke, and its main coking coal ratio is above 40%, this method is not suitable for coking plants with low main coking coal ratio

[0011] 6) CN 105131995 "Coal blending method for controlling coke wear resistance", in this method, the proportion of weakly caking coal with low degree of metamorphism is high (0-20), and the proportion of weakly caking coal with high metamorphism degree is high (18-5), Moreover, the proportion of main coking coal is above 40%, and the wear resistance of coke is controlled by increasing the proportion of fat coal and reducing the proportion of coking coal by 1 / 3. This method is not suitable for coking plants with a low proportion of main coking coal.