阅读说明：本技术 改善捣固焦配合煤细度和粒度组成的方法 (Method for improving fineness and granularity composition of tamping coke blended coal ) 是由 任华伟 杨洪庆 郎莹 王华东 李建莉 孙振满 翟记川 晋常兵 刘利园 于 2020-06-03 设计创作，主要内容包括：本发明涉及一种改善捣固焦配合煤的细度和粒度组成的方法。所述方法结合哈氏可磨指数和原始细度,对一些难磨煤或原始颗粒也较粗的煤进行预粉碎,使预粉碎更有针对性；通过取配合煤中>3mm的部分进行煤岩相分析,根据镜质组各反射率区间分布比例判断是到底是哪类煤造成粒度不合格,能快速找到配合煤粒度不达标的原因,针对性调整,避免目前为了提高配合煤细度,对所有预粉碎煤或配合煤提高粉碎水平,既会造成部分煤粉碎过细,又造成能耗增加；通过针对性粉碎,控制>5mm部分和＜0.5mm部分的比例,达到了入炉煤最佳粒度组成。通过该方法使炼焦所得焦炭达到高强度、大块度,提升质量水平。(The invention relates to a method for improving fineness and granularity composition of tamping coke blended coal. The method combines the Hardgrove grindability index and the original fineness to pre-crush coal which is difficult to grind or has thicker original particles, so that the pre-crushing is more targeted; the method comprises the steps of performing coal-rock phase analysis on a part with the size larger than 3mm in the blended coal, judging which type of coal is unqualified in granularity according to the distribution proportion of each reflectivity interval of a vitrinite, quickly finding out the reason that the granularity of the blended coal does not reach the standard, performing targeted adjustment, and avoiding the problems that the crushing level of all pre-crushed coal or blended coal is improved in order to improve the fineness of the blended coal at present, so that part of coal is crushed to be too fine, and the energy consumption is increased; the optimal granularity composition of the coal as fired is achieved by the targeted pulverization and the control of the proportion of the part of more than 5mm and the part of less than 0.5 mm. The method ensures that the coke obtained by coking has high strength and large lumpiness and improves the quality level.)

1. A method for improving the fineness and the granularity composition of the tamping coke blended coal comprises the following steps:

1) coal with Hardgrove grindability index less than 60% in each single coal is taken as coal difficult to grind;

2) coal with original fineness of less than 60 percent in each single coal is taken as coarse-grained coal, wherein the original fineness refers to the weight percentage of parts with grain diameters of less than 3mm in the total weight of the coal;

3) the coal difficult to grind or coarse coal is sent to a pre-grinding section to be respectively and independently pre-ground, the fineness and the granularity are required to be less than 5mm and reach 100 percent, and less than 3mm accounts for more than 87 percent;

4) mixing the pre-crushed coal and other coals according to a ratio to form blended coal, and crushing and uniformly mixing the blended coal and the blended coal;

5) the fineness and the granularity composition of the blended coal are measured, and if the proportion of the part with the particle size of 3mm is more than 90 percent and the proportion of the part with the particle size of 5mm is 0, and the proportion of the part with the particle size of 0.5mm is less than 40 percent, the process requirement is met;

6) if it can not satisfy "<The 3mm proportion accounts for more than 90 percent>5mm ofTaking the mixture into the blended coal according to the process requirement of the proportion of 0>Performing coal-rock phase analysis on the 3mm part, and analyzing the obtained maximum vitrinite reflectivity R_maxDetermining the coal types causing the fineness and the granularity composition not to meet the process requirements according to the table 1;

table 1: the maximum vitrinite reflectance corresponds to the possible coal types:

R_max/％ possible coal classes arranged by frequency of occurrence <0.5 Lignite, long flame coal 0.5～<0.6 Long flame coal, non-stick coal and gas coal 0.6～<0.7 Gas coal, long flame coal, non-stick coal, gas fat coal 0.7～<0.8 Gas coal, gas fat coal, weak caking coal, non-caking coal, 1/2 medium caking coal 0.8～<0.9 1/3 coking coal, gas coal, weakly caking coal, non-caking coal, fat coal, and gas fat coal 0.9～<1.0 1/3 coking coal, fat coal, gas coal, 1/2 medium-viscosity coal, and gas fat coal 1.0～<1.1 Fat coal, 1/3 coking coal 1.1～<1.2 Fat coal, 1/3 coking coal and coking coal 1.2～<1.3 Coking coal, fat coal, 1/3 coking coal 1.3～<1.4 Coking coal, fat coal 1.4～<1.5 Coking coal 1.5～<1.6 Coking coal, lean coal and poor lean coal 1.6～<1.7 Lean coal, coking coal and poor lean coal 1.7～<1.8 Lean coal, poor lean coal, coking coal and lean coal 1.8～<1.9 Lean coal, lean coal and lean coal 1.9～<2.0 Lean coal, lean coal and lean coal 2.0～<2.5 Lean coal >＝2.5 Anthracite and lean coal

7) According to the judgment result of 6), improving the fineness level of the coal causing unqualified fineness and granularity composition, for example, improving the fineness level of the coal by adjusting pre-crushing equipment and operation, such as increasing the hammer head of the pre-crushing equipment, adjusting the distance and the like; or increasing the pre-crushing times by 1-2 times, and improving the fineness level of the coal by repeatedly crushing;

8) if the requirement is not met, properly widening the definition parameter range of the difficult-to-grind coal or the coarse-grained coal by 5 to 10 percent to add 1 to 2 kinds of coal for pre-grinding;

9) if the process requirement of <0.5mm proportion is less than 40% "cannot be met, the coal with caking index G value of more than 70 in the coal difficult to grind or coarse coal is not separately pre-crushed;

10) and detecting the fineness and the granularity composition of the blended coal, and if the fineness and the granularity composition of the blended coal do not meet the requirements, repeatedly adjusting according to the steps to finally meet the process requirements.

2. The method of improving the fineness and particle size composition of stamp-charged coke-blended coal according to claim 1, further comprising the step of measuring the Hardgrove grindability index of each individual coal prior to step 1).

3. The method of improving the fineness and particle size composition of stamp-charged coke-blended coal according to claim 1, further comprising the step of measuring the original fineness of each individual coal prior to step 2).

4. A coking production process, comprising:

(1) the method for improving the fineness and the grain size composition of the stamp-charging coke blended coal according to any one of claims 1 to 3 is adopted to obtain the blended coal with the fineness and the grain size composition of more than 90% of the part with the fineness and the grain size composition of more than 3mm and 0 of the part with the fineness and the grain size composition of less than 40% of the part with the fineness and the grain size composition of more than 5 mm;

(2) the blended coal is used for tamping coking.

Technical Field

The invention belongs to the field of coking in the coking industry, and particularly relates to a method for improving fineness and granularity composition of tamping coke blended coal.

Background

The influence of the crushing fineness and the granularity of the coal on the coke quality is great, and researches show that the caking capacity of the blended coal can be improved by optimizing the fineness of the blended coal, so that the coke quality is improved. However, the compositions of the particle sizes of the coal as fired with the same fineness are greatly different, and the quality of the produced coke is also greatly different. The coking property and the crushing property of different lithofacies compositions in different kinds of raw material coal and the same kind of raw material coal are different, the low-metamorphic-degree coal such as common long flame coal, weakly caking coal, gas coal and the like and the high-metamorphic-degree coal such as lean coal, poor lean coal, lean coal and the like belong to coal which is difficult to grind, and the original particles are thick and need to be finely crushed; while some fat coal and coking coal are easy-to-grind coal, the original particles are also coarse, so fine crushing is also needed. The prior domestic coke-oven plant generally adopts a process of 'mixing before pulverizing', the process flow is simple, the investment is small, but the defects of uneven pulverization, insufficient fineness and the like exist.

Although pre-crushing equipment is also arranged in the tamping coke process to pre-crush part of coal, the crushing fineness (<3 mm) of the coal as fired is generally between 85 and 90 percent, the requirement that the design is more than or equal to 90 percent cannot be met, and the part with the particle size of less than 0.5mm in the blended coal is more than 40 percent. The large fineness of coal can cause coke cracks, which leads to the reduction of the cold strength of the coke and the small lumpiness, while the coking deterioration of the pulverized coal less than 0.5mm leads to the reduction of the coke strength.

Disclosure of Invention

Aiming at the technical problems, the invention provides a method for improving the granularity and components of the tamping coke mixed with coal. The method ensures that the coke obtained by coking has high strength and large lumpiness and improves the quality level.

The method for improving the fineness and the granularity composition of the tamping coke blended coal comprises the following steps:

1) coal with Hardgrove Grindability Index (HGI) of less than 60 percent in each single coal is taken as difficult-to-grind coal;

2) coal with original fineness of less than 60 percent in each single coal is taken as coarse-grained coal, wherein the original fineness refers to the weight percentage of parts with grain diameters of less than 3mm in the total weight of the coal;

3) the coal difficult to grind or coarse coal is sent to a pre-grinding section to be respectively and independently pre-ground, the fineness and the granularity are required to be less than 5mm and reach 100 percent, and less than 3mm accounts for more than 87 percent;

4) mixing the pre-crushed coal and other coals according to a ratio to form blended coal, and crushing and uniformly mixing the blended coal and the blended coal;

5) the fineness and the granularity composition of the blended coal are measured, and if the proportion of the part with the particle size of 3mm is more than 90 percent and the proportion of the part with the particle size of 5mm is 0, and the proportion of the part with the particle size of 0.5mm is less than 40 percent, the process requirement is met;

6) if it can not satisfy "<The 3mm proportion accounts for more than 90 percent>Taking the 5mm coal blend according to the process requirement of 0 ″>Performing coal-rock phase analysis on the 3mm part, and analyzing the obtained maximum vitrinite reflectivity R_maxDetermining the coal types causing the fineness and the granularity composition not to meet the process requirements according to the table 1;

table 1: the maximum vitrinite reflectance corresponds to the possible coal types:

Rmax/％	possible coal classes arranged by frequency of occurrence
		<0.5	Lignite, long flame coal
0.5～<0.6	Long flame coal, non-stick coal and gas coal
		0.6～<0.7	Gas coal, long flame coal, non-stick coal, gas fat coal
0.7～<0.8	Gas coal, gas fat coal, weak caking coal, non-caking coal, 1/2 medium caking coal
		0.8～<0.9	1/3 coking coal, gas coal, weakly caking coal, non-caking coal, fat coal, and gas fat coal
0.9～<1.0	1/3 coking coal, fat coal, gas coal, 1/2 medium-viscosity coal, and gas fat coal
		1.0～<1.1	Fat coal, 1/3 coking coal
1.1～<1.2	Fat coal, 1/3 coking coal and coking coal
		1.2～<1.3	Coking coal, fat coal, 1/3 coking coal
1.3～<1.4	Coking coal, fat coal
		1.4～<1.5	Coking coal
1.5～<1.6	Coking coal, lean coal and poor lean coal
		1.6～<1.7	Lean coal, coking coal and poor lean coal
1.7～<1.8	Lean coal, poor lean coal, coking coal and lean coal
		1.8～<1.9	Lean coal, lean coal and lean coal
1.9～<2.0	Lean coal, lean coal and lean coal
		2.0～<2.5	Lean coal
>＝2.5	Anthracite and lean coal

7) According to the judgment result of 6), improving the fineness level of the coal causing unqualified fineness and granularity composition, for example, improving the fineness level of the coal by adjusting pre-crushing equipment and operation, such as increasing the hammer head of the pre-crushing equipment, adjusting the distance and the like; or increasing the pre-crushing times by 1-2 times, and improving the fineness level of the coal by repeatedly crushing;

8) if the requirement is not met, properly widening the definition parameter range of the difficult-to-grind coal or the coarse coal by 5-10 percent to add 1-2 kinds of coal for pre-grinding, for example, adjusting the Hardgrove grindability index HGI to be less than 70 percent to be used as the difficult-to-grind coal; coal with fineness less than 70% is taken as coarse-grained coal;

9) if the process requirement of <0.5mm proportion is less than 40% "cannot be met, the coal with caking index G value of more than 70 in the coal difficult to grind or coarse coal is not separately pre-crushed;

10) and detecting the fineness and the granularity composition of the blended coal, and if the fineness and the granularity composition of the blended coal do not meet the requirements, repeatedly adjusting according to the steps to finally meet the process requirements.

The method for improving the fineness and the granularity composition of the stamp-charging coke blended coal can also comprise the step of measuring the Hardgrove Grindability Index (HGI) of each single coal before the step 1).

The method for improving the fineness and the granularity composition of the stamp-charging coke blended coal can also comprise the step of measuring the original fineness of each single coal before the step 2).

The Hardgrove Grindability Index (HGI) was used to determine the degree of difficulty of crushing a single coal, and was determined according to the method specified in MT/T230-2005 "Universal technical conditions for Hardgrove grindability index measurement apparatus". The original fineness refers to the fineness of each single coal<The 3mm particles, as a weight percentage of the total weight of the coal, were measured according to the method specified in GB/T477-2008 "coal screening test methods". Maximum reflectance R of vitrinite_maxThe method is characterized in that a coal rock microscopic testing method is used, and the maximum reflectance value of a vitrinite is measured by rotating an objective table under single polarization; the measurement was carried out according to the method defined in GB/T6948-2008 "microscopic reflectance measurement method for coal".

After the blended coal meeting the process requirements is obtained, the blended coal can be used for coking.

Accordingly, the present invention also relates to a coking production process comprising:

(1) the method for improving the fineness and the granularity composition of the tamping coke blended coal is adopted to obtain the blended coal with the fineness and the granularity composition of more than 90 percent of the part with the fineness and the granularity composition of more than 3mm and 0 of the part with the fineness and the granularity composition of less than 40 percent of the part with the fineness and the granularity composition of more than 5 mm;

(2) the blended coal is used for tamping coking.

The step of using the blended coal for stamp-charging coking is not particularly limited, and may be performed by any method available in the art. For example, tamping coking can be carried out at a predetermined temperature, for example 1000 ± 50 ℃, for a certain coking time according to a coking curve set by the coke oven used.

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

innovatively provides that the Hardgrove grindability index and the original fineness are combined, and the coal which is difficult to grind or has thicker original particles is pre-ground, so that the pre-grinding is more targeted.

The method comprises the steps of taking a part with the size of more than 3mm in the blended coal to perform coal-rock phase analysis, judging which type of coal is unqualified in granularity according to the distribution proportion of each reflectivity interval of a vitrinite, and quickly finding out the reason that the granularity of the blended coal does not reach the standard.

By targeted pulverization, control>The proportion of the 5mm part and the less than 0.5mm part achieves the optimal granularity composition of the coal as fired. Under the dry quenching condition of a tamping coke oven with more than 4.3 meters and without coal moisture control, briquette and additives, the coke obtained by the method has the thermal strength CRI of 25-30 percent, the CSR of 62-70 percent and the cold strength M₂₅90-95%, M₁₀3 to 6 percent of the coke, and the average particle size of the coke is more than 47 mm.

In the present invention, unless explicitly indicated otherwise, the percentages (%) refer to weight percentages.

Detailed Description

The above description is only an overview of the technical solutions of the present invention, and the technical means of the present invention can be more clearly understood and implemented according to the content of the description, and the present invention will be further described below by specifically referring to the embodiments of the present invention. However, the present invention is not limited thereto.

Test method

Bonding index (G value): the method is determined according to GB/T50047-2014 method for determining the bituminous coal caking index.

Y value: the measurement is carried out according to GB/T479-2016 method for measuring the colloidal layer index of bituminous coal.

Original fineness: the determination is carried out according to GB/T477-2008 'coal screening test method'.

Hardgrove Grindability Index (HGI): the determination is carried out according to MT/T230-2005 Universal technical conditions for the Hardgrove grindability index determinator.

The cold strength of the coke comprises crushing strength (M)₂₅) And abrasion resistance (M)₁₀): the measurement was carried out according to the first method in GB/T2006 + 2008 "method for measuring mechanical Strength of Coke".

The thermal strength includes Coke Reactivity (CRI) and post-reaction strength (CSR): the determination is carried out according to GB/T4000-2017 'test method for coke reactivity and strength after reaction'.

Average particle size: the screening particle size composition proportion of the coke is measured according to GB/T2005-1994 method for measuring the coke powder content and screening composition of metallurgical coke, and is calculated according to the following formula:

average particle size 90 × S_≥80+70×S_≥80-60+50×S_≥60-40+32.5×S_≥40-25+17.5×S_≤25

In the formula S_≥80、S_≥80-60、S_≥60-40、S_≥40-25、S_≤25Respectively the proportion of more than 80mm, the proportion of 60-80mm, the proportion of 40-60mm, the proportion of 25-40mm and the proportion of less than 25 mm.