Coal blending system and coking method for improving reactivity of coke

Abstract

This invention discloses a coal blending system for improving coke reactivity and a coking method using this coal blending system. The coal blending system comprises Y coal, low-branched fat coal, and high hydrogen-to-oxygen ratio lean coal. Specifically, the Y coal has a drum index for inertia > 86% and an aromaticity fa of 0.70 ≤ fa ≤ 0.77; the low-branched fat coal has a branching degree of 1.31 ≤ CH2 / CH3 ≤ 1.86 and an aliphatic hydrogen / total hydrogen ratio of 0.59 ≤ H2 / CH3. al / H all ≤0.76; Hydrogen content H of lean coal with high hydrogen-to-oxygen ratio daf ≥4.24%, oxygen content O daf The content of coking coal particles is ≤3.78%, and the hydrogen-to-oxygen ratio (H / O) is ≥1.53. In the mixed coal formed by pulverizing Y-coal, low-branched fat coal, and high-hydrogen-to-oxygen-ratio lean coal, the proportion of particles larger than 1.5 mm and smaller than 1.0 mm is controlled as follows: ≤21% for particles larger than 1.5 mm and ≤61% for particles smaller than 1.0 mm. This invention can effectively improve the reactivity of coke, thereby creating favorable conditions for reducing the coke ratio in blast furnaces, significantly reducing the amount of high-quality coking coal used, and lowering the coal blending costs for coking enterprises.

Description

Technical Field

[0001] This invention belongs to the field of coking coal blending technology, and particularly relates to a coal blending system and coking method for improving the reactivity of coke. Background Technology

[0002] In recent years, with the development and application of large-scale blast furnaces, high-quality coke has become the foundation for the efficient and low-carbon operation of large blast furnaces. Large blast furnaces place higher demands on the reactivity of coke. Coke reactivity reflects the ability of coke to chemically react with CO2, O2, and water vapor under high-temperature conditions, and has a significant impact on the stable and smooth operation of the blast furnace. Low coke reactivity makes it prone to carbon melting reaction and cracking in the blast furnace, reduces the coke's crushing and abrasion resistance, and allows coke powder to enter the slag, reducing the slag's fluidity and decreasing the permeability of the burden column in the furnace, resulting in fluctuations in furnace conditions.

[0003] Coke reactivity is calibrated by the CRI value; the lower the CRI value, the better (higher) the coke reactivity, which is more conducive to the stable and smooth operation of the blast furnace. To improve coke reactivity and reduce the CRI value, existing coking coal blending technologies are mainly improved in the following two aspects:

[0004] One method involves adding non-coal materials that enhance caking properties. Chinese invention patent application number 201110177991.7 discloses a method for coking coal blending. In this method, 0.5%–5% hard pitch is added by weight percentage based on the weight percentage of the blended coal or a single type of coal. The mixture is then thoroughly mixed, pulverized, and coked. The hard pitch has a softening point of 105–115℃, a toluene-insoluble content of 15%–25%, a quinoline-insoluble content of 3%–6%, a β-resin content of 12%–20%, a coking value of 45%–65%, an ash content ≤0.3%, and a moisture content ≤1.0%. However, according to the embodiments of this patent, the blending scheme uses a certain proportion of high-volatile gas coal or 100 parts of 1 / 3 coking coal. This results in a very high volatile content in the blended coal, significant shrinkage of the semi-coke, numerous pores inside the coke, and reduced coke reactivity, failing to meet the requirements for 4000m³ coking. 3 Requirements for the use of large blast furnaces of grade A and above.

[0005] Second, a special element passivating agent is added. Chinese invention patent application No. 201810947340.3 discloses a coke with excellent thermal properties and its preparation method. The composition of the blended coal by weight is as follows: 45-55 parts of 1 / 3 coking coal, 10-20 parts of lean coal, 15-25 parts of prime coking coal, 3-8 parts of mixed coal, and 10-15 parts of fat coal. By weight, the blended coal also includes 0.03-0.05 parts of aluminum fluoride, 0.01-0.02 parts of yttrium chloride, 0.1-0.2 parts of boric acid, 0.1-0.2 parts of borax, 0.1-0.2 parts of boron oxide, 0.4-0.5 parts of titanium boride, and 1-3 parts of titanium dioxide. However, according to claim 1 of the patent, step 2 of the method for preparing coke with excellent thermal properties employs a special restrictive process of "tamping"; according to claim 1 of the patent, step 3 of the method for preparing coke with excellent thermal properties contains 5-10% sodium chloride and 50-60% surfactant in its quenching water, and the surfactant component includes 60% sodium dodecylbenzenesulfonate, indicating that its quenching water contains a large amount of free sodium. + Na during coke quenching + It will enter the pore structure of coke and adhere to the surface of the pore structure of coke. As is well known, Na... + As an alkali metal element, it has a positive catalytic effect on the reactivity of coke, thus reducing its reactivity. Furthermore, the coal blending scheme in this patent application has a proportion of over 45% coking coal (1 / 3), along with a certain percentage of lean coal. The large proportion of high-volatile coking coal increases the volatile matter content of the blended coal and the porosity of the coke, failing to significantly improve its reactivity. Lean coal has poor caking properties and contains more inert substances, increasing the internal crack structure of the coke, reducing its size, and increasing the specific surface area of ​​the coke of the same mass. This intensifies the carbon-fusion reaction with CO2, leading to decreased reactivity. Moreover, this patent requires numerous steps, making the process complex and requiring a variety of chemical reagents, resulting in high production costs.

[0006] Therefore, it is necessary to develop an easy-to-implement coal blending system and coking method that can improve the reactivity of coke, for 4000m³ 3 Creating favorable conditions for reducing the coke ratio in blast furnaces of 800 blast furnaces and above, and reducing the coal blending costs of coking enterprises, are important technical problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0007] To address the technical problems existing in the prior art, the present invention provides a coal blending system and a coking method for improving the reactivity of coke.

[0008] In one aspect of the present invention, the provided coal blending system for improving coke reactivity comprises: Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal, wherein the inertia capacity drum index of the Y coal is... The aromaticity fa is 0.70 ≤ fa ≤ 0.77; the branching degree of the low-branched coking coal is 1.31 ≤ CH2 / CH3 ≤ 1.86, and the aliphatic hydrogen / total hydrogen ratio is 0.59 ≤ H. al / H all ≤0.76.

[0009] Furthermore, in the aforementioned coal blending system for improving coke reactivity, the hydrogen content H of the high hydrogen-to-oxygen ratio lean coal is... daf ≥4.24%, oxygen content O daf ≤3.78%, H / O ratio ≥1.53.

[0010] Furthermore, in the above-mentioned coal blending system for improving coke reactivity, the weight ratio of the Y coal, the low-branched fat coal, and the high hydrogen-oxygen ratio lean coal is 24-36:16-25:14-19.

[0011] Furthermore, in the aforementioned coal blending system for improving coke reactivity, the coal blending system also includes 1 / 3 coking coal and coke.

[0012] Furthermore, in the aforementioned coal blending system for improving coke reactivity, the weight percentages of the Y coal, the low-branched fat coal, the high hydrogen-oxygen ratio lean coal, the 1 / 3 coking coal, and the coking coal are respectively: Y coal 24-36%, low-branched fat coal 16-25%, high hydrogen-oxygen ratio lean coal 14-19%, 1 / 3 coking coal 11-17%, and coking coal 12-16%.

[0013] Furthermore, in the aforementioned coal blending system for improving coke reactivity, the proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal formed by pulverizing the Y coal, the low-branched fat coal, and the high hydrogen-oxygen ratio lean coal is controlled as follows: the proportion of particles larger than 1.5 mm ≤ 21%, and the proportion of particles smaller than 1.0 mm ≤ 49% ≤ 61%.

[0014] In another aspect of the invention, the coking method for improving the reactivity of coke includes: coking using the above-described coal blending system.

[0015] Furthermore, the aforementioned coking methods for improving coke reactivity specifically include:

[0016] Step 1: Mix and crush Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal to obtain mixed coal;

[0017] Step 2: Mix the mixed coal with 1 / 3 coking coal and coke to obtain blended coal;

[0018] Step 3: Use the aforementioned blended coal to produce coke.

[0019] Furthermore, in the above-mentioned coking method for improving coke reactivity, in step one, the proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm ≤ 21%, and the proportion of particles smaller than 1.0 mm ≤ 49% ≤ 61%.

[0020] Furthermore, in the above-mentioned coking method for improving coke reactivity, in step three, the coking heating regime adopted is as follows: coking time 24.6-25.3h, standard temperature 1312-1321℃, and dry quenching method.

[0021] The coal blending system and coking method for improving coke reactivity of the present invention have the following advantages and beneficial effects:

[0022] The coal blending system and coking method of the present invention for improving coke reactivity control the CRI value of coke to 18.2%–22.3% by incorporating a certain proportion of Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal into the coal blending system. This effectively improves the coke reactivity, thereby enabling coke to achieve a reactivity of 4000m³. 3 The reduction of coke ratio in blast furnaces of 1000 and above creates favorable conditions, significantly reducing the amount of high-quality coking coal resources used and lowering the coal blending cost of coking enterprises. Moreover, the coal blending system and coking method of the present invention for improving coke reactivity only require the selection of single coking coal, adjustment of coal blending structure and control of blended coal particle size. There is no need to add additional strongly binding non-coal substances or special element passivating agents. It has no special restrictions on production process conditions, is easy to organize and implement in production, and does not increase coal blending cost or production and manufacturing cost. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0024] In general, the coal blending system for improving coke reactivity and the coking method using this coal blending system of the present invention improve coke reactivity and reduce the CRI value by incorporating a certain proportion of Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal into the coal blending system. Specifically, the coal blending system for improving coke reactivity of the present invention includes: Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal, wherein the Y coal is selected based on its inertia drum index. Its aromaticity fa is 0.70≤fa≤0.77; the low-branched coking coal selected is characterized by a branching degree of 1.31≤CH2 / CH3≤1.86 and an aliphatic hydrogen / total hydrogen ratio of 0.59≤H. al / H all ≤0.76; high hydrogen-to-oxygen ratio lean coal is selected based on its hydrogen content H. daf ≥4.24%, its oxygen content O daf ≤3.78%, with a hydrogen-to-oxygen ratio (H / O) ≥1.53.

[0025] As a specific implementation method, in the above-mentioned coal blending system for improving coke reactivity, the weight ratio of Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal is 24-36:16-25:14-19.

[0026] Furthermore, the aforementioned coal blending system for improving coke reactivity also includes 1 / 3 coking coal and coke.

[0027] As a specific implementation method, in the above-mentioned coal blending system for improving coke reactivity, the weight percentages of Y coal, low-branched fat coal, high hydrogen-oxygen ratio lean coal, 1 / 3 coking coal, and coking coal are as follows: Y coal 24-36%, low-branched fat coal 16-25%, high hydrogen-oxygen ratio lean coal 14-19%, 1 / 3 coking coal 11-17%, and coking coal 12-16%.

[0028] Furthermore, in the aforementioned coal blending system for improving coke reactivity, the proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal formed by pulverizing Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal is controlled as follows: the proportion of particles larger than 1.5 mm ≤ 21%, and the proportion of particles smaller than 1.0 mm ≤ 49% ≤ 61%.

[0029] In another aspect of the invention, the coking method for improving the reactivity of coke includes: coking using the above-described coal blending system.

[0030] Furthermore, the aforementioned coking methods for improving coke reactivity specifically include:

[0031] Step 1: Mix and crush Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal to obtain mixed coal;

[0032] Step 2: Mix the blended coal with 1 / 3 coking coal and coke to obtain blended coal;

[0033] Step 3: Use the above-mentioned blended coal to produce coke.

[0034] Furthermore, in the above-mentioned coking method for improving coke reactivity, in step one, the proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm ≤ 21%, and the proportion of particles smaller than 1.0 mm ≤ 49% ≤ 61%.

[0035] Furthermore, in the above-mentioned coking method for improving coke reactivity, in step three, the coking heating regime adopted is as follows: coking time 24.6-25.3h, standard temperature 1312-1321℃, and dry quenching method.

[0036] The above-mentioned test method for inertia tolerance is as follows: using the drum index The change value was used as the judgment criterion. Referring to YB / T4526-2016 "Technical Specification for Small Coke Ovens for Coking Tests", 15% inert material (non-caking lean coal) was added to the coking coal to conduct a 40kg test coke oven coking experiment. Then, the drum index of the coke was determined according to JIS K2151-2004 "Test Methods for Coke". This is used to determine the inertia tolerance.

[0037] In the coal blending system and coking method for improving coke reactivity of the present invention, by blending Y coal, high hydrogen-oxygen ratio lean coal, and low-branched fat coal and mixing and pulverizing the three, while controlling their particle size distribution, the latent defects in coke structure can be reduced, thereby improving coke reactivity. Specifically: Y coal is a high-capacity inert coal, which can produce more stable and strongly binding liquid phase substances during coking pyrolysis; low-branched fat coal is a coking coal with low aliphatic branch content, low branching degree, and long aliphatic chain length, and has a more stable molecular structure. During the pyrolysis plastic stage of coking pyrolysis, the degree of pyrolysis is low, and a stable liquid intermediate phase can be formed; high hydrogen-oxygen ratio lean coal is a high-hydrogen, low-oxygen, and highly inert coal. The low oxygen content indicates that it has fewer oxygen-containing functional groups, which is beneficial for coking. During pyrolysis, it is not easy to generate volatile substances and consumes less hydrogen free radicals. Due to its high hydrogen-to-oxygen ratio, lean coal has more inert substances, which can provide more condensation nuclei for the plastic liquid intermediate phase after being mixed with it, thus playing a role in the organizational structure. Y coal has a strong inertness tolerance, low branching degree of low-branched fat coal and long aliphatic chain length. After being mixed with lean coal with a high hydrogen-to-oxygen ratio, by controlling the proportion of particles >1.5mm and <1.0mm, Y coal can impregnate and encapsulate the inert substances of lean coal with a high hydrogen-to-oxygen ratio, forming stable interfacial molecular carbon bridges. The hydrogen free radicals of lean coal with a high hydrogen-to-oxygen ratio can generate more non-volatile plastics with the long aliphatic chains of low-branched fat coal. During the coking process, the coke layer is dense with thick pore walls and low porosity, with fewer hidden defects in the coke structure and high coke reactivity.

[0038] According to GB / T 4000-2014 "Test Methods for Coke Reactivity and Post-Reaction Strength", the coke produced by the method of improving coke reactivity of the present invention was tested for coke reactivity. The CRI value was only 18.2% to 22.3%, which shows that the coal blending system and coking method of the present invention can effectively improve coke reactivity.

[0039] The following describes the coal blending system and coking method for improving coke reactivity of the present invention with reference to specific embodiments and comparative examples. The coke ovens used in the following comparative examples and embodiments are all 7.63m coke ovens.

[0040] Example 1

[0041] The specific implementation process of Example 1 includes:

[0042] I. Preparation of blended coal

[0043] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 24%, low-branched fat coal 25%, high-hydrogen-ratio lean coal 19%, 1 / 3 coking coal 17%, and coking coal 15%. The blended coal preparation included:

[0044] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 21% and the proportion of particles smaller than 1.0 mm is 61%.

[0045] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0046] II. Smelting coke

[0047] The coking process using the above-mentioned blended coal is as follows: coking time 25.3h, standard temperature 1313℃, and dry quenching method.

[0048] Actual testing showed that the CRI value of the coke prepared using Example 1 was 22.3%, indicating that the reactivity of the coke was effectively improved.

[0049] Example 2

[0050] The specific implementation process of Example 2 includes:

[0051] I. Preparation of blended coal

[0052] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-to-oxygen ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 36%, low-branched fat coal 22%, high-hydrogen-to-oxygen ratio lean coal 16%, 1 / 3 coking coal 13%, and coking coal 13%. The blended coal preparation included:

[0053] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 17% and the proportion of particles smaller than 1.0 mm is 57%.

[0054] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0055] II. Smelting coke

[0056] The coking process using the above-mentioned blended coal is as follows: coking time 25.1h, standard temperature 1315℃, and dry quenching method.

[0057] Actual testing showed that the CRI value of the coke prepared using Example 2 was 19.7%, indicating that the reactivity of the coke was effectively improved.

[0058] Example 3

[0059] The specific implementation process of Example 3 includes:

[0060] I. Preparation of blended coal

[0061] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 36%, low-branched fat coal 16%, high-hydrogen-ratio lean coal 15%, 1 / 3 coking coal 17%, and coking coal 16%. The blended coal preparation included:

[0062] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 15% and the proportion of particles smaller than 1.0 mm is 55%.

[0063] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0064] II. Smelting coke

[0065] The coking process using the above-mentioned blended coal is as follows: coking time 25.0 h, standard temperature 1318 ℃, and dry quenching method.

[0066] Actual testing showed that the CRI value of the coke prepared using Example 3 was 20.4%, indicating that the reactivity of the coke was effectively improved.

[0067] Example 4

[0068] The specific implementation process of Example 4 includes:

[0069] I. Preparation of blended coal

[0070] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 35%, low-branched fat coal 24%, high-hydrogen-ratio lean coal 14%, 1 / 3 coking coal 11%, and coking coal 16%. The blended coal consisted of:

[0071] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 10% and the proportion of particles smaller than 1.0 mm is 49%.

[0072] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0073] II. Smelting coke

[0074] The coking process using the above-mentioned blended coal is as follows: coking time 24.6h, standard temperature 1321℃, and dry quenching method.

[0075] Actual testing showed that the CRI value of the coke prepared using Example 4 was 19.3%, indicating that the reactivity of the coke was effectively improved.

[0076] Example 5

[0077] The specific implementation process of Example 5 includes:

[0078] I. Preparation of blended coal

[0079] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 30%, low-branched fat coal 20%, high-hydrogen-ratio lean coal 17%, 1 / 3 coking coal 17%, and coking coal 16%. The blended coal preparation included:

[0080] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 13% and the proportion of particles smaller than 1.0 mm is 59%.

[0081] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0082] II. Smelting coke

[0083] The coking process using the above-mentioned blended coal is as follows: coking time 24.8h, standard temperature 1319℃, and dry quenching method.

[0084] Actual testing showed that the CRI value of the coke prepared using Example 5 was 21.1%, indicating that the reactivity of the coke was effectively improved.

[0085] Example 6

[0086] The specific implementation process of Example 6 includes:

[0087] I. Preparation of blended coal

[0088] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 36%, low-branched fat coal 25%, high-hydrogen-ratio lean coal 14%, 1 / 3 coking coal 11%, and coking coal 14%. The blended coal preparation included:

[0089] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 7% and the proportion of particles smaller than 1.0 mm is 60%.

[0090] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0091] II. Smelting coke

[0092] The coking process using the above-mentioned blended coal is as follows: coking time 25.3h, standard temperature 1312℃, and dry quenching method.

[0093] Actual testing showed that the CRI value of the coke prepared using Example 6 was 18.2%, indicating that the reactivity of the coke was effectively improved.

[0094] Example 7

[0095] The specific implementation process of Example 7 includes:

[0096] I. Preparation of blended coal

[0097] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 34%, low-branched fat coal 24%, high-hydrogen-ratio lean coal 18%, 1 / 3 coking coal 12%, and coking coal 12%. The blended coal preparation included:

[0098] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 5% and the proportion of particles smaller than 1.0 mm is 53%.

[0099] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0100] II. Smelting coke

[0101] The coking process using the above-mentioned blended coal is as follows: coking time 25.1h, standard temperature 1315℃, and dry quenching method.

[0102] Actual testing showed that the CRI value of the coke prepared using Example 7 was 18.5%, indicating that the reactivity of the coke was effectively improved.

[0103] Example 8

[0104] The specific implementation process of Example 8 includes:

[0105] I. Preparation of blended coal

[0106] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 28%, low-branched fat coal 23%, high-hydrogen-ratio lean coal 18%, 1 / 3 coking coal 16%, and coking coal 15%. The blended coal consisted of:

[0107] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 9% and the proportion of particles smaller than 1.0 mm is 51%.

[0108] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0109] II. Smelting coke

[0110] The coking process using the above-mentioned blended coal is as follows: coking time 24.9h, standard temperature 1319℃, and dry quenching method.

[0111] Actual testing showed that the CRI value of the coke prepared using Example 8 was 20.8%, indicating that the reactivity of the coke was effectively improved.

[0112] Example 9

[0113] The specific implementation process of Example 9 includes:

[0114] I. Preparation of blended coal

[0115] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 29%, low-branched fat coal 19%, high-hydrogen-ratio lean coal 19%, 1 / 3 coking coal 17%, and coking coal 16%. The blended coal consisted of:

[0116] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 8% and the proportion of particles smaller than 1.0 mm is 58%.

[0117] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0118] II. Smelting coke

[0119] The coking process using the above-mentioned blended coal is as follows: coking time 24.7h, standard temperature 1320℃, and dry quenching method.

[0120] Actual testing showed that the CRI value of the coke prepared using Example 9 was 21.3%, indicating that the reactivity of the coke was effectively improved.

[0121] Example 10

[0122] The specific implementation process of Example 10 includes:

[0123] I. Preparation of blended coal

[0124] A blended coal was prepared using Y-coal, low-branched fat coal, high-hydrogen-ratio lean coal, 1 / 3 coking coal, and coking coal as raw materials. The weight percentages of each raw material in the blended coal were controlled as follows: Y-coal 27%, low-branched fat coal 21%, high-hydrogen-ratio lean coal 19%, 1 / 3 coking coal 17%, and coking coal 16%. The blended coal consisted of:

[0125] (1) Mix Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal and then crush them to obtain mixed coal. The proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm in the mixed coal is controlled as follows: the proportion of particles larger than 1.5 mm is 19% and the proportion of particles smaller than 1.0 mm is 56%.

[0126] (2) The prepared mixed coal is mixed with 1 / 3 coking coal and coke to prepare blended coal;

[0127] II. Smelting coke

[0128] The coking process using the above-mentioned blended coal is as follows: coking time 25.2h, standard temperature 1314℃, and dry quenching method.

[0129] Actual testing showed that the CRI value of the coke prepared using Example 10 was 21.8%, indicating that the reactivity of the coke was effectively improved.

[0130] The coal quality data for Y coal, high hydrogen-oxygen ratio lean coal, low-branched fat coal, 1 / 3 coking coal, and coking coal used in Examples 1 to 10 above are shown in Table 1:

[0131] Table 1

[0132]

[0133] The inertia capacity drum index of Y coal used in Examples 1 to 10 above For the aromaticity fa, please refer to Table 2:

[0134] Table 2

[0135]

[0136] The degree of branching and the ratio of aliphatic hydrogen to total hydrogen used in Examples 1 to 10 above are shown in Table 3:

[0137] Table 3

[0138]

[0139] The high hydrogen-to-oxygen ratio lean coal used in Examples 1 to 10 above has a hydrogen content H daf Oxygen content O daf For the hydrogen-to-oxygen ratio (H / O), please refer to Table 4:

[0140] Table 4

[0141]

[0142] Comparative Example 1

[0143] The specific implementation process of Comparative Example 1 is as follows:

[0144] (1) A blended coal is obtained by mixing 51% coking coal, 32% fat coal, 7% 1 / 3 coking coal and 10% lean coal by weight.

[0145] (2) Coking, the coking heating regime is as follows: coking time 24.3h, standard temperature 1325℃, and coking quenching method is dry quenching.

[0146] Actual testing showed that the CRI value of the coke prepared using Comparative Example 1 was 26.9%, which was higher than the CRI value of the coke prepared using Examples 1 to 10 of this invention, indicating that the coke had lower reactivity.

[0147] Comparative Example 2

[0148] The specific implementation process of Comparative Example 2 is as follows:

[0149] (1) A blended coal is obtained by mixing 41% coking coal, 12% fat coal, 22% 1 / 3 coking coal and 25% lean coal by weight.

[0150] (2) Coking, the coking heating regime is as follows: coking time 24.1h, standard temperature 1329℃, and coking quenching method is dry quenching.

[0151] Actual testing showed that the CRI value of the coke prepared using Comparative Example 2 was 27.2%, which was higher than the CRI value of the coke prepared using Examples 1 to 10 of this invention, indicating that the coke had lower reactivity.

[0152] Comparative Example 3

[0153] The specific implementation process of Comparative Example 3 is as follows:

[0154] (1) A blended coal is obtained by mixing 43% coking coal, 34% fat coal, 5% 1 / 3 coking coal, 6% lean coal and 12% gas coal by weight.

[0155] (2) Coking, the coking heating regime is as follows: coking time 25.7h, standard temperature 1308℃, and coking quenching method is dry quenching.

[0156] Actual testing showed that the CRI value of the coke prepared using Comparative Example 3 was 26.4%, which was higher than the CRI value of the coke prepared using Examples 1 to 10 of this invention, indicating that the coke had lower reactivity.

[0157] Comparative Example 4

[0158] The specific implementation process of Comparative Example 4 is as follows:

[0159] (1) A blended coal is obtained by mixing 20% ​​coking coal, 29% fat coal, 6% 1 / 3 coking coal, 9% lean coal, 17% gas coal and 19% gas-fat coal by weight.

[0160] (2) Coking, the coking heating regime is as follows: coking time 26.4h, standard temperature 1301℃, and coking quenching method is dry quenching.

[0161] Actual testing showed that the CRI value of the coke prepared using Comparative Example 4 was 27.6%, which was higher than the CRI value of the coke prepared using Examples 1 to 10 of this invention, indicating that the coke had lower reactivity.

[0162] In summary, the coal blending system and coking method of the present invention for improving coke reactivity, by incorporating a certain proportion of Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal into the coal blending system, controls the CRI value of coke to 18.2%–22.3%, which is far lower than the 26.4%–27.6% of the prior art. This effectively improves coke reactivity, thereby providing high-reactivity, high-quality metallurgical coke for large blast furnaces. More specifically, the method for improving coke reactivity of the present invention has the following advantages and beneficial effects:

[0163] 1. Effectively improves the reactivity of coke to 4000m 3 The reduction of coke ratio in blast furnaces of 1000 and above creates favorable conditions, significantly reducing the amount of high-quality coking coal used and lowering the coal blending costs for coking enterprises.

[0164] 2. Only the selection of a single type of coking coal, the adjustment of the coal blending structure, and the control of the particle size of the blended coal are required. There is no need to add additional non-coal substances with strong binding properties or special element passivating agents. There are no special restrictions on the production process conditions. It is easy to organize and implement production and does not increase the cost of coal blending or production.

[0165] It should be noted that, unless otherwise expressly stated, the technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention pertains. For example, the following references provide basic guidance for those skilled in the art regarding the technical terms used herein:

[0166] He Xuanming, Coal Chemistry, Metallurgical Industry Press, 2nd edition, 2010;

[0167] Pan Lihui, Q&A on Coking Technology, Metallurgical Industry Press, 2013;

[0168] Yao Zhaozhang, Coking Science, 3rd edition, Metallurgical Industry Press, 2010;

[0169] Xu Zhengang, Clean Coal Technology in China, Coal Industry Press, 2012;

[0170] Lin Cong, Encyclopedia of Chinese Metallurgy, Metallurgical Industry Press, 1998;

[0171] Ma Shichang, Dictionary of Chemical Substances, Shaanxi Science and Technology Press, 1999;

[0172] China Coal Classification Standard GB / T5751-2009; General Table of China Coal Classification, 1989.

[0173] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the present invention.

Claims

1. A coal blending system for improving the reactivity of coke, characterized in that, The coal blending system includes Y coal, low-branched fat coal, and high hydrogen-oxygen ratio lean coal, wherein the Y coal is the inertia drum index. High-volume inert coal with an aromaticity (fa) of >86% and an aroma content (fa) of 0.70 ≤ fa ≤ 0.77; the low-branched fat coal has a branching degree of 1.31 ≤ CH2 / CH3 ≤ 1.86 and an aliphatic hydrogen / total hydrogen ratio of 0.59 ≤ H. al / H all ≤0.76; the high hydrogen-to-oxygen ratio lean coal refers to coal with a hydrogen content of H... daf ≥4.24%, oxygen content O daf High-hydrogen, low-oxygen, highly inert coal with a hydrogen-to-oxygen ratio (H / O) ≥ 1.53 and a content of ≤ 3.78%, including: The weight ratio of the Y coal, the low-branched fat coal, and the high hydrogen-oxygen ratio lean coal is 24~36 : 16~25 : 14~19; In the mixed coal formed by pulverizing the Y coal, the low-branched fat coal, and the high hydrogen-oxygen ratio lean coal, the proportion of particles larger than 1.5 mm and particles smaller than 1.0 mm is controlled as follows: the proportion of particles larger than 1.5 mm ≤ 21%, and the proportion of particles smaller than 1.0 mm ≤ 49% ≤ 61%.

2. The coal blending system for improving coke reactivity according to claim 1, characterized in that, The coal blending system also includes 1 / 3 coking coal and coke.

3. The coal blending system for improving coke reactivity according to claim 2, characterized in that, The weight percentages of Y coal, low-branched fat coal, high hydrogen-oxygen ratio lean coal, 1 / 3 coking coal, and coking coal are as follows: Y coal 24-36%, low-branched fat coal 16-25%, high hydrogen-oxygen ratio lean coal 14-19%, 1 / 3 coking coal 11-17%, and coking coal 12-16%.

4. A coking method for improving the reactivity of coke, characterized in that, include: Coking is carried out using the coal blending system described in claim 3.

5. The coking method for improving coke reactivity according to claim 4, characterized in that, include: Step 1: Mix and crush Y coal, low-branched fat coal and high hydrogen-oxygen ratio lean coal to obtain mixed coal; Step 2: Mix the mixed coal with 1 / 3 coking coal and coke to obtain blended coal; Step 3: Use the aforementioned blended coal to produce coke.

6. The coking method for improving coke reactivity according to claim 5, characterized in that, In step three, the coking heating regime adopted is as follows: coking time 24.6~25.3h, standard temperature 1312~1321℃, and coking quenching method is dry quenching.

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