A coking coal caking index determination method based on particle size compensation

Abstract

The application discloses a coking coal caking index determination method based on granularity compensation and belongs to the technical field of detection. R.I. When G is 18, the coking coal caking index G is accurately determined through the following formula I: G=G R.I. -a*(35-A) I, wherein A is the proportion of coal samples with a granularity of 0.1mm-0.2mm in the sample, the value of A is 20-35, the value of a is 0.11 or-0.18, G R.I. is the caking index determined according to the coking coal caking index determination method in GB / T 5447-2014, and the formula for determining the coking coal caking index is constructed on the basis of considering the granularity, the G value result is accurately reported, and it is very necessary to reduce the quality abnormality of both supply parties.

Description

Technical Field

[0001] This invention relates to the field of detection technology, and more specifically, to a method for determining the caking index of coking coal based on particle size compensation. Background Technology

[0002] Coking property is a characteristic exhibited by coal during dry distillation, forming a colloid. It is a necessary condition for coking and is closely related to the coking properties of coal. The caking index is a measure of the strength of the bond between coal particles and between coal and inert additive particles after coal is heated in the absence of air; it is the final result of various physical and thermochemical changes. Based on the magnitude of the coal sample's caking index, the main use of the coal can be roughly determined, whether it is suitable for coking, gasification, or other processing technologies.

[0003] Studies have shown that the particle size of coal samples has a significant impact on the caking index, directly affecting the accuracy of the measurement. However, current tests on the viscosity index of coking coal are all conducted using national standards, and the influence of coal sample particle size on the caking index is not taken into account. Therefore, the caking index of the coal sample cannot be accurately reflected.

[0004] With the soaring price of coking coal, it is essential to develop a method to compensate for the impact of particle size on the detection of coking coal caking index, accurately report G-value results, and reduce quality anomalies on both the supply and demand sides.

[0005] Given the aforementioned problems, it is necessary to provide a method for determining the caking index of coking coal based on particle size compensation. Summary of the Invention

[0006] The purpose of this invention is to overcome the defects of the prior art and provide a method for determining the caking index of coking coal based on particle size compensation.

[0007] The technical problem solved by this invention is achieved by the following technical solution.

[0008] This invention provides a method for determining the caking index of coking coal based on particle size compensation. According to the classification of coking coal caking properties, G... R.I. When the caking index G of coking coal is greater than 18, the following formula I is used to accurately determine the caking index G of the coking coal:

[0009] G=G R.I. - a*(35-A) Ⅰ

[0010] Where A% represents the proportion of coal samples with a particle size of 0.1mm-0.2mm in the sample, with A ranging from 20% to 35%, and a ranging from 0.11 to -0.18, G R.I. The caking index is determined according to the GB / T 5447-2014 method for determining the caking index of bituminous coal.

[0011] The present invention has the following beneficial effects:

[0012] This invention provides a method for determining the caking index of coking coal based on particle size compensation. In this invention, based on a fully tested sample particle size, a formula is established to accurately report the G value, which is more objective, accurate, and universal. In practical applications, the accurate reporting of the G value result can reduce quality abnormalities for both suppliers and customers. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0014] The following is a detailed description of a method for determining the caking index of coking coal based on particle size compensation, provided by an embodiment of the present invention.

[0015] This invention provides a method for determining the caking index of coking coal based on particle size compensation. According to the classification of coking coal caking properties, G... R.I. When the caking index G of coking coal is greater than 18, the following formula I is used to accurately determine the caking index G of the coking coal:

[0016] G=G R.I. - a*(35-A) Ⅰ

[0017] Where A% represents the proportion of coal samples with a particle size of 0.1mm-0.2mm in the sample, with A ranging from 20% to 35%, and a ranging from 0.11 to -0.18, G R.I. The caking index is determined according to GB / T 5447-2014, the method for determining the caking index of bituminous coal.

[0018] In an optional implementation, based on the caking properties of coking coal, 18 <G R.I. When the caking index G of coking coal is ≤65, it is accurately determined by the following formula II:

[0019] G=G R.I. +(35-A)*0.18Ⅱ

[0020] Where A% represents the proportion of coal samples with a particle size of 0.1mm-0.2mm in the sample, and the value of A ranges from 20% to 35%. R.I. The caking index is determined according to the GB / T 5447-2014 method for determining the caking index of bituminous coal.

[0021] In an optional implementation, based on the caking properties of coking coal, G R.I. When the caking index is >65, the caking index of coking coal is accurately determined using the following formula (III):

[0022] G=G R.I. -(35-A)*0.11Ⅲ

[0023] Where A% represents the proportion of coal samples with a particle size of 0.1mm-0.2mm in the sample, and the value of A ranges from 20% to 35%. R.I. The caking index is determined according to the GB / T 5447-2014 method for determining the caking index of bituminous coal.

[0024] In an optional implementation, the adhesion index G R.I. The determination method is as follows: Coal samples are prepared by stepwise crushing and reduction according to GB474 to obtain general analytical coal samples with a particle size of less than 0.2 mm, of which the proportion of coal samples with a particle size of 0.1 mm-0.2 mm is 20%-35%. The coal sample and special standard anthracite are mixed in a 1+5 ratio under specified conditions to obtain a sample, which is then rapidly heated to form coke. The resulting coke blocks are tested for strength in a rotating drum. The abrasion resistance of the coke blocks is used to represent the coal's bonding ability. The experimental results are expressed as G. R.I. Indicates the adhesion index G R.I. The calculation formula is as follows:

[0025]

[0026] In the formula, m is the total amount of coke residue after coking treatment of the coal sample, in g; m1 is the mass of the portion remaining on the sieve after the first drum test, in g; m2 is the mass of the portion remaining on the sieve after the second drum test, in g; if G R.I. If the value is less than 18, then another test needs to be conducted using a 3+3 ratio of coal sample and anthracite.

[0027] In an optional implementation, a method for determining the coking coal caking index based on particle size compensation is used to determine the application of the coking coal caking index in auxiliary coal blending.

[0028] The above embodiments of the present invention provide a method for determining the caking index of coking coal based on particle size compensation. For coals with a G value greater than 18, and those with a G value less than 18 (which are considered lean coals), particle size compensation is not very meaningful. This method is derived by fully considering the influence of coking coal particle size on caking properties. This is because multiple studies and practices have found that the particle size of coking coal has a significant impact on the caking index. Currently, the caking index measured according to GB / T 5447-2014 "Method for Determining Caking Index of Bituminous Coal" does not consider the influence of particle size on the caking index.

[0029] Currently, coal is classified according to its caking properties, usually using the caking index: 1-5 indicates non-caking and slightly caking coal, greater than 50-65 indicates moderately to strongly caking coal, and greater than 65 indicates strongly caking coal. Caking Index (G) R.I.The specific testing method is as follows: Coal samples and special standard anthracite are mixed in a 1+5 ratio under specified conditions, rapidly heated to form coke, and the resulting coke blocks are tested for strength in a drum of a certain specification (Roga drum). The abrasion resistance of the coke blocks represents the coal's caking ability, and the experimental results are expressed as G. R.I. Indicates the adhesion index G. R.I. The calculation formula is as follows:

[0030]

[0031] In the formula, m is the total amount of coke residue after coking treatment of the coal sample, in g; m1 is the mass of the portion remaining on the sieve after the first drum test, in g; m2 is the mass of the portion remaining on the sieve after the second drum test, in g; if G R.I. If the value is less than 18, then another test needs to be conducted using a 3+3 ratio of coal sample and anthracite.

[0032] In the above tests, GB / T 5447-2014 specifies that the test coal samples should be prepared by stepwise crushing and reduction according to GB474 to obtain general analytical test coal samples with a particle size of less than 0.2 mm, of which the particle size is 0.1 mm-0.2 mm. The proportion of coal samples with a particle size of 0.1 mm-0.2 mm is between 20% and 35%. In fact, theoretically, the smaller the coal particle size, the higher the caking index. This rule generally applies to bituminous coals with moderate or strong caking properties. For bituminous coals with weak caking properties, because they are prone to oxidation and metamorphism, smaller particle sizes are more prone to oxidation and metamorphism, thus reducing caking properties; for strongly caking coals, the increasing effect is not significant.

[0033] Through long-term practice, the inventors have proposed a method to compensate for the influence of particle size on the detection of coking coal caking index. This method fully considers the influence of particle size on the caking index of coal samples. Compared with improving the accuracy of the caking index by improving the sample preparation process, such as grinding time, grinding amount, mill speed and coking temperature, the method of establishing a formula in this invention accurately reports the G value result, which is more objective, accurate and universal.

[0034] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0035] This invention provides a method for determining the caking index of coking coal based on particle size compensation, the steps of which are as follows:

[0036] Adhesion Index G R.I.The determination method is as follows: Coal samples are prepared by stepwise crushing and reduction according to GB474 to obtain general analytical coal samples with a particle size of less than 0.2 mm, of which the proportion of coal samples with a particle size of 0.1 mm-0.2 mm is 20%-35%. The coal sample and special standard anthracite are mixed in a 1+5 ratio under specified conditions to obtain a sample, which is then rapidly heated to form coke. The resulting coke blocks are tested for strength in a rotating drum. The abrasion resistance of the coke blocks is used to represent the coal's bonding ability. The experimental results are expressed as G. R.I. Indicates the adhesion index G R.I. The calculation formula is as follows:

[0037]

[0038] In the formula, m is the total amount of coke residue after coking treatment of the coal sample, in g; m1 is the mass of the portion remaining on the sieve after the first drum test, in g; m2 is the mass of the portion remaining on the sieve after the second drum test, in g; if G R.I. If the value is less than 18, then another test needs to be conducted using a 3+3 ratio of coal sample and anthracite.

[0039] The proportion of coal samples with a particle size of 0.1 mm to 0.2 mm was determined to be A%.

[0040] For different coking coals, by using different G... R.I. For each sample preparation, coal samples with a particle size of 0.1 mm to 0.2 mm were prepared at a ratio of 20% to 35%, and the samples were tested according to GB / T 5447-2014 to obtain relevant data. Each sample was then compared with GB / T 5447-2014 according to the particle size ratio. R.I. Plot a curve, and based on the slope and slope distance of the curve, establish a formula. The accurate G value can be obtained by using the established formula.

[0041] Example 1

[0042] The proportion of coal samples with a particle size of 0.1 mm to 0.2 mm was determined to be A%.

[0043] For 18 <G R.I. When ≤65, by using 7 different G R.I. For each sample preparation, coal samples with a particle size of 0.1 mm to 0.2 mm were prepared at a ratio of 20% to 35%, and the tests were performed according to GB / T 5447-2014. The relevant data are shown in Table 1 below:

[0044] Table 1

[0045]

[0046] Based on the statistical analysis of the table above, and considering the influence of particle size on the adhesion index detection, we obtain G=G R.I.+ (35-A)*0.18. It should be noted that if the G value is <18, the sample needs to be prepared again and the test needs to be repeated.

[0047] Example 2

[0048] The proportion of coal samples with a particle size of 0.1 mm to 0.2 mm was determined to be A%.

[0049] For G R.I. >65, by using 5 different G R.I. For each sample preparation, coal samples with a particle size of 0.1 mm to 0.2 mm were prepared at a ratio of 20% to 35%, and the tests were performed according to GB / T 5447-2014. The relevant data are shown in Table 2 below:

[0050] Table 2

[0051]

[0052] Based on the statistical analysis of the table above, and considering the influence of particle size on the adhesion index detection, we obtain G=G R.I. -(35-A)*0.11.

[0053] Experimental Example 1

[0054] The following coal samples were tested: Tianhong high-sulfur coking coal (JYP-2208300090), Changlong medium-sulfur No. 1 coking coal (JYP-220824003584), Hunan 1 / 3 coking coal (JYP-2209040025), Bao'e coking coal (JYP-2209030018), and Liangbei lean coal (JYP-2209030125). These samples were mixed and reduced to 3 kg each, and then sent to the Shaogang Coking Laboratory, Shaogang Central Laboratory, Chongqing Steel Laboratory, and Sansteel Laboratory. The laboratories directly used national standards for sample preparation and testing. The test data are shown in Table 3 below.

[0055] Table 3

[0056]

[0057] 18 <G R.I. When the caking index G of coking coal is ≤65, it is accurately determined by the following formula:

[0058] G=G R.I. + (35-A)*0.18

[0059] For G R.I. When the caking index is >65, the caking index of coking coal is accurately determined using the following formula:

[0060] G=G R.I. -(35-A)*0.11

[0061] For the coal samples tested in Table 3 above, the caking index (G value) was calculated using the formula described above, and the results are shown in Table 4 below:

[0062] Table 4

[0063]

[0064] It can be seen that for different types of coal samples, the G values ​​obtained by different testing units after sample preparation and testing according to national standards vary greatly, while the G values ​​obtained by calculation using the formula are basically the same, that is, the formula can accurately report the G value results.

[0065] Experimental Example 2

[0066] A batch of lean coal from Liangbei with inspection batch number JYP-2209120016 was prepared according to national standards by four shifts (A, B, C, and D). The same person in the laboratory conducted the tests on the same equipment according to national standards. The data is shown in Table 5 below.

[0067] Table 5

[0068]

[0069] The caking index G of coking coal is accurately determined by the following formula:

[0070] G=G R.I. + (35-A)*0.18

[0071] For the coal samples prepared by different sample preparation personnel as shown in Table 5 above, the caking index (G value) was calculated using the formula described above, and the results are shown in Table 6 below:

[0072] Table 6

[0073]

[0074] It can be seen that for the same type of coal sample, the G values ​​obtained by different personnel in preparing the sample and testing it according to the national standard vary greatly, while the G values ​​obtained by calculating using the formula are basically the same, that is, the formula can accurately report the G value results.

[0075] As can be seen from the above, the embodiments of the present invention provide a method for determining the caking index of coking coal based on particle size compensation. By constructing a calculation formula for the caking index based on particle size compensation, the G-value result is accurately reported, reducing quality abnormalities for both suppliers and customers.

[0076] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the caking index of coking coal based on particle size compensation, characterized in that, According to the classification of coking coal caking properties, G R.I. When the caking index G of coking coal is greater than 18, the following formula I is used to accurately determine the caking index G of the coking coal: G=G R.I. - a*(35-A) Ⅰ Where A% represents the proportion of coal samples with a particle size of 0.1mm-0.2mm in the sample, with A ranging from 20% to 35%, and a ranging from 0.11 to -0.18, G R.I. The caking index is determined according to the GB / T 5447-2014 method for determining the caking index of bituminous coal.

2. The method for determining the caking index of coking coal based on particle size compensation according to claim 1, characterized in that, According to the classification of coking coal based on its caking properties, 18 <G R.I. When the caking index G of coking coal is ≤65, it is accurately determined by the following formula II: G=G R.I. +(35-A)*0.18Ⅱ Where A% is the proportion of coal sample with a particle size of 0.1mm-0.2mm in the sample, and G R.I. The caking index is determined according to the GB / T 5447-2014 method for determining the caking index of bituminous coal.

3. The method for determining the caking index of coking coal based on particle size compensation according to claim 1, characterized in that, According to the classification of coking coal caking properties, G R.I. When the caking index is >65, the caking index of coking coal is accurately determined using the following formula (III): G=G R.I. -(35-A)*0.11Ⅲ Where A% is the proportion of coal sample with a particle size of 0.1mm-0.2mm in the sample, and G R.I. The caking index is determined according to the GB / T 5447-2014 method for determining the caking index of bituminous coal.

4. The method for determining the caking index of coking coal based on particle size compensation according to any one of claims 1-3, characterized in that, The adhesion index G R.I. The determination method is as follows: Coal samples are prepared by stepwise crushing and reduction according to GB474 to obtain general analytical coal samples with a particle size of less than 0.2 mm, of which the proportion of coal samples with a particle size of 0.1 mm-0.2 mm is 20%-35%. The coal sample and special standard anthracite are mixed in a 1+5 ratio under specified conditions to obtain a sample, which is then rapidly heated to form coke. The resulting coke blocks are tested for strength in a rotating drum. The abrasion resistance of the coke blocks is used to represent the coal's bonding ability. The experimental results are expressed as G. R.I. Indicates the adhesion index G R.I. The calculation formula is as follows: In the formula, m is the total amount of coke residue after coking of the coal sample, in g; m1 is the mass of the sieve residue after the first drum test, in grams; m2 is the mass of the sieve residue after the second drum test, in grams. If G R.I. If the value is less than 18, then another test needs to be conducted using a 3+3 ratio of coal sample and anthracite.

5. The method for determining the coking coal caking index based on particle size compensation according to any one of claims 1-3 determines the application of the coking coal caking index in auxiliary coal blending.

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