CN113845932A

CN113845932A - Method for blending and coking lean coke coal in Shanxi province

Info

Publication number: CN113845932A
Application number: CN202110896096.4A
Authority: CN
Inventors: 付利俊; 李晓炅; 李春燕
Original assignee: Baotou Iron and Steel Group Co Ltd
Current assignee: Baotou Iron and Steel Group Co Ltd
Priority date: 2021-08-05
Filing date: 2021-08-05
Publication date: 2021-12-28

Abstract

The invention discloses a method for blending and coking lean coking coal in Shanxi province, which adopts the following blending ratio in percentage by mass: 30-55% of coking coal, 10-25% of fat coal, 5-20% of 1/3 coking coal, 5-15% of gas coal and 10-25% of lean coking coal. The method utilizes the characteristics of low volatile component and high thermal property of lean coking coal in Shanxi province, enlarges the coal consumption with low metamorphism degree by adjusting the coal blending structure, saves high-quality coking coal, and can effectively improve the strength of coke. The method has strong practical operability, obvious economic benefit, strong practical applicability and wide popularization and application prospect.

Description

Method for blending and coking lean coke coal in Shanxi province

Technical Field

The invention relates to the field of coking and coal blending, in particular to a method for coking by blending lean coking coal in Shanxi province.

Background

The dry ash-free base volatile component Vdaf of the lean coking coal is more than 10-20%, the caking index G is more than 65, the colloidal layer thickness index Y is less than 25mm, and a certain amount of colloidal bodies can be generated during coking. The coke produced by single coal coking has the advantages of general meltability, small abrasion resistance, easy crushing, and large coke lumpiness. The additive is commonly used as a thinning agent for coal blending coking, and the lean coking coal in the coking blended coal can play a role in skeleton and shrinkage stress, so that the lump size of the coke is increased. However, the lean coking coal cannot be blended in a large amount, otherwise the coke strength is affected. Therefore, how to effectively utilize the lean coking coal for coking by blending coal, improve the coke quality and reduce the coal blending cost becomes a focus of the coking and coal blending industry.

The prior lean coking coal blending method mainly comprises the following steps:

1) CN 105623697A "a coking coal blending method with participation of lean coking coal" mainly provides a lean coking coal blending ratio of up to 30%, thereby enlarging the coking coal blending variety, and utilizes vitrinite reflectance distribution diagram to blend coal, but the coking coal in actual use at present is almost mixed coal, and vitrinite reflectance guidance for mixed coal blending is very poor, and the coal blending property can not be truly reflected.

2) CN 112080311A "coking coal blending and coking method for producing first-class metallurgical coke by blending a large amount of lean coal" proposes a coking coal blending and coking method for producing first-class metallurgical coke by blending a large amount of lean coal. The method mainly causes serious pollution to coal blending, and seriously affects physical and mental health of workers in the first-line production.

3) CN 112094662A entitled "a coking and coal blending method" provides a coking and coal blending method with a low main coke coal blending structure for controlling coke wear resistance, and the method uses the coke wear resistance M10 of a small coke oven as a control index. The method mainly focuses on the abrasion resistance M10 of the coke, and cannot comprehensively reflect the strength index of the coke, particularly the thermal property of the coke.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a method for blending and coking lean coke coal in Shanxi province.

In order to solve the technical problems, the invention adopts the following technical scheme:

the invention relates to a coking and coal blending method by utilizing Shanxi lean coking coal, which adopts the following coal blending ratio in percentage by mass: 30-55% of coking coal, 10-25% of fat coal, 5-20% of 1/3 coking coal, 5-15% of gas coal and 10-25% of lean coking coal.

Further, the coking and coal blending method adopts the following coal blending ratio in percentage by mass: 30% of coking coal, 25% of fat coal, 7% of 1/3 coking coal, 13% of gas coal and 25% of lean coking coal.

Further, the coking and coal blending method adopts the following coal blending ratio in percentage by mass: 42% of coking coal, 18% of fat coal, 13% of 1/3 coking coal, 10% of gas coal and 17% of lean coking coal.

Further, the coking and coal blending method adopts the following coal blending ratio in percentage by mass: 53% of coking coal, 11% of fat coal, 18% of 1/3 coking coal, 8% of gas coal and 10% of lean coking coal.

Further, the resulting coke is produced: the crushing strength M40 is more than 90%, M10 is less than 6%, and CSR is more than 65%.

Compared with the prior art, the invention has the beneficial technical effects that:

the invention provides a coking and coal blending method of Shanxi lean coke coal, which utilizes the characteristics of low volatile matter and high thermal property of the Shanxi lean coke coal, enlarges the coal consumption with low metamorphic grade by adjusting the coal blending structure, saves high-quality coking coal and can effectively improve the strength of coke. The method has strong practical operability, obvious economic benefit, strong practical applicability and wide popularization and application prospect.

Drawings

The invention is further illustrated in the following description with reference to the drawings.

FIG. 1 is a lithofacies map of lean coke coal from Shanxi.

Detailed Description

In order to effectively utilize lean coal in Shanxi province to coke and mix coal, the invention carries out test coke oven coking, including coal industrial analysis, coal rock analysis, caking property and coke performance analysis. And (3) formulating a plurality of coal blending ratio schemes according to various properties of lean coking coals in Shanxi, and finally determining a reasonable coal blending ratio for use in production according to the quality effect of the test coke.

The present invention will be described in detail with reference to specific examples.

Example 1: shanxi lean coke coal performance analysis

Carrying out test coke oven coking on Shanxi lean coke coal, and carrying out various performance analyses on coal types, including coal industrial analysis, caking property analysis, coal rock analysis and coke strength analysis.

The research results of the coke oven in the Shanxi lean coke coal test are shown in Table 1.

TABLE 1 results of various indexes of lean coke coal in Shanxi province

According to the data result analysis of the table 1, the ash content and the sulfur content of the coal are moderate, the volatile component is low, the lumpiness of the coke can be improved, the crushing strength of the coke is improved, the CSR of 40kg test coke is high, and the thermal performance of the coke can be improved.

Example 2: carrying out analysis of different coal blending ratios according to production requirements

The coal blending scheme in this example consisted of lean coke, coking coal, fat coal, 1/3 coking coal, and gas coal, and the various coals were crushed to a fineness of 78 + -2% (-200 mesh), then mixed and blended according to the coal blending ratio listed in table 2 below, and the blended coals were coked in the test coke oven. According to the coke quality and coal blending cost of different schemes, the coal blending scheme with high selectivity price ratio is adopted. In the coal blending production process, the precise coal blending operation ensures the accuracy of the coal blending ratio and cannot miss blending or mismatch.

Table 2: according to the different coal blending ratio (%) of the production requirements

Coal blending ratio	Coking coal	Fat coal		1/3 coking coal	Gas coal	Lean coke coal
							Coal blending ratio of 1	30	25	7	13	25
Coal blending ratio 2	42	18	13	10	17
						Coal blending ratio 3	53	11	18	8	10

In the coking process, various heating systems and operation methods of the coke oven are ensured to be normal and stable. When the central temperature of the coke cake reaches 950-1050 ℃, the coke is confirmed to be matured. When the coke cake is determined to be mature, the coke is pushed out for quenching (quenching process comprises a dry quenching method or a wet quenching method). Then crushing, screening and grading are carried out to obtain coke products with different particle sizes, and the coke products are respectively sent to users such as a blast furnace, sintering and the like for use.

The coke quality obtained from the above coal ratios is shown in table 3 below.

Table 3: actual coke quality results

Coal blending ratio	Ash (%)	Sulfur content (%)	M₄₀(％)	M₁₀(％)	CRI(％)	CSR(％)
							Coal blending ratio of 1	12.37	0.86	90.13	5.58	24.31	65.24
Coal blending ratio 2	12.58	0.87	90.39	5.62	23.51	66.29
							Coal blending ratio 3	12.61	0.88	90.84	5.06	23.06	67.13

From the coke quality data analysis in Table 3, the crushing strengths M40 are all greater than 90%, M10 is less than 6%, CRI is less than 25%, and CSR is more than 65%. After the thin coke coal in Shanxi province is added, the coke can meet the production requirement of the blast furnace, and the stable and smooth operation of the blast furnace is ensured.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.

Claims

1. A method for blending and coking lean coke coal in Shanxi is characterized in that: the following coal blending ratio in percentage by mass is adopted: 30-55% of coking coal, 10-25% of fat coal, 5-20% of 1/3 coking coal, 5-15% of gas coal and 10-25% of lean coking coal.

2. The method for blending and coking the lean coke coal in Shanxi according to claim 1, wherein: the following coal blending ratio in percentage by mass is adopted: 30% of coking coal, 25% of fat coal, 7% of 1/3 coking coal, 13% of gas coal and 25% of lean coking coal.

3. The method for blending and coking the lean coke coal in Shanxi according to claim 1, wherein: the following coal blending ratio in percentage by mass is adopted: 42% of coking coal, 18% of fat coal, 13% of 1/3 coking coal, 10% of gas coal and 17% of lean coking coal.

4. The method for blending and coking the lean coke coal in Shanxi according to claim 1, wherein: the following coal blending ratio in percentage by mass is adopted: 53% of coking coal, 11% of fat coal, 18% of 1/3 coking coal, 8% of gas coal and 10% of lean coking coal.

5. The method for blending and coking the lean coke coal in Shanxi according to any one of claims 1 to 4, wherein: production of the resulting coke: the crushing strength M40 is more than 90%, M10 is less than 6%, and CSR is more than 65%.