Coal calorific value calculation method

Abstract

The invention discloses a coal calorific value calculation method which comprises the following steps: establishing a theoretical calculation formula of coal sample as received basis lower calorific value Y and the sum X of total moisture and as received basis ash: Y = AX + B, where A and B are constants; the method comprises the following steps: determining the total moisture, as received basis ash content and as received basis lower calorific value of a coal sample of a target mine by a standard method, and performing linear regression fitting to determine the values of constants A and B; in actual detection, on the premise of measuring total moisture, only one parameter of as received basis ash content and as received basis low calorific value needs to be measured, and the other parameter which is not directly measured is calculated in combination with the theoretical formula. According to the method, the as-received basis lower calorific value or the as-received basis ash content can be calculated only under the condition that the total moisture and the as-received basis lower calorific value are measured, and the error between the calculation result and the measured value meets the requirement of a standard method.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermal power generation and coal chemical industry, and particularly relates to a coal calorific value calculation method. BACKGROUND

[0002] Currently, coal quality detection mainly relies on national standard methods, and complete determination of three indexes of total moisture, ash content and calorific value needs to be independently performed, and repeated sample processing leads to superposition of human and time costs, and detection cost is high. Traditional offline detection process (sampling -> sample preparation -> laboratory analysis) takes about 4-8 hours, and cannot provide real-time data support for production links such as coal blending and boiler optimization. The three indexes are determined in the laboratory respectively, and there is a lack of internal logical checking mechanism, when some data is abnormal (such as sample preparation representation problem, operator error, instrument control condition difference, etc.), the data reliability cannot be quickly identified. SUMMARY

[0003] Based on this, the purpose of the present application is to provide a coal calorific value calculation method, which can calculate received base low calorific value or received base ash content under the condition of only determining total moisture and received base ash content, or only determining total moisture and received base low calorific value, and the calculation result error meets the standard method requirement.

[0004] To achieve the above purpose, the present application adopts the following technical scheme: The present application provides a coal calorific value calculation method, which comprises the following steps: S1. A theoretical calculation formula of received base low calorific value Y of a coal sample and a sum X of total moisture and received base ash content is established: Y=AX+B, wherein A and B are constants; S2. The values of constants A and B are determined by performing linear regression fitting on the basis of standard method determination of total moisture, received base ash content and received base low calorific value of a target coal sample of a mine; S3. In actual detection, only one of received base ash content and received base low calorific value needs to be determined under the premise of determining total moisture, and the other parameter not directly determined is calculated by combining the theoretical formula.

[0005] As a further improvement of the above scheme of the present application, in step S2, the determination method of the constants A and B comprises: Standard method determination of total moisture, received base ash content and received base low calorific value is performed on multiple batches of coal samples of the same mine; Linear regression is performed with the sum X of total moisture and received base ash content as the abscissa and received base low calorific value Y as the ordinate to obtain the values of constants A and B.

[0006] As a further improvement of the above-mentioned scheme of the present application, in step S3, when the coal is crushed to a particle size of ≤6 mm, the on-line total moisture meter is used to obtain the total moisture data in real time. When the coal is crushed to a particle size of ≤6 mm or ≤3 mm, the on-line ash content meter is used to obtain the received basis ash content data in real time. The real-time obtained total moisture and received basis ash content data are input into the formula Y=AX+B, and the received basis low calorific value is dynamically calculated in real time.

[0007] As a further improvement of the above-mentioned scheme of the present application, the obtained received basis low calorific value, total moisture and received basis ash content data are used for: Generating a batch coal quality fluctuation curve to judge the uniformity of incoming coal or the stability of calorific value; Taking the average of the continuous determination data as the batch coal quality parameter result; Guiding the coal blending and calorific value control in the production process of coal-fired or chemical raw coal.

[0008] As a further improvement of the above-mentioned scheme of the present application, the on-line total moisture determination uses light wave rapid determination technology, and the on-line ash content determination uses spectrum analysis technology.

[0009] As a further improvement of the above-mentioned scheme of the present application, the theoretical calculation formula is used to judge whether the coal sample determination data is normal, specifically: The determined total moisture, ash content and calorific value data are substituted into the Y=AX+B theoretical calculation formula, and if the error of the calculation result and the actual determination value exceeds the range required by the standard method, it is judged that the ash content and calorific value data of the coal sample determination are abnormal.

[0010] As a further improvement of the above-mentioned scheme of the present application, the deviation of the calculated received basis low calorific value and the measured value is ≤72 kcal / kg. The ash content (Aad%) deviation meets the requirements of the national standard GBT 30732, when Aad%<15%, the deviation is ≤0.3%; when 15%≤Aad%≤30%, the deviation is ≤0.5%; when Aad%>30%, the deviation is ≤0.7%. Generally, the absolute value average of the ash content deviation of multiple batches of coal samples of the same mine is less than 0.27%, and the absolute value average of the ash content deviation of multiple batches of coal slurry samples is less than 0.34%.

[0011] Compared with the prior art, the present application has the following beneficial effects: The present application can calculate and obtain the received basis low calorific value or the received basis ash content only when the total moisture and the received basis ash content are determined, or only when the total moisture and the received basis low calorific value are determined, and the error of the calculation result and the measured value meets the requirements of the standard method.

[0012] Theoretical calculation formula established by the application, the coal research institute or the user, only needs to measure the total moisture, ash content and calorific value of a certain coal, and then the constants A and B of the calculation formula can be obtained, and other users or daily testing do not need to measure the ash content or calorific value by instruments to obtain the data, which greatly saves the equipment, energy, manpower and time resource cost.

[0013] The simple quantitative relationship between the coal quality determination parameters of the coal of the application is Y = AX + B, which can be calculated instead of measured, and the instruments and methods conforming to the national and international standards for measuring total moisture, ash content and calorific value can be used to meet the requirements without additional investment; 30%-50% of the cost of 3 items can be saved, the work efficiency can be improved by 30%-50%, and the prospect of technical application space breakthrough is achieved. DETAILED DESCRIPTION

[0014] In order to facilitate the understanding of the application, the application will be described more fully below with reference to specific embodiments. However, the application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the application more thorough and comprehensive.

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application belongs. The terms used in the specification of the application herein are only for the purpose of describing the specific embodiments and are not intended to limit the application.

[0016] The embodiment provides a coal calorific value calculation method, which comprises the following steps: S1. Establishing a theoretical calculation formula of the received base low calorific value Y of the coal sample and the sum X of the total moisture and the received base ash content: Y = AX + B, wherein A and B are constants.

[0017] S2. Determining the values of the constants A and B by linear regression fitting through standard method determination of the total moisture, received base ash content and received base low calorific value of the target coal sample. Specifically: The total moisture, received base ash content and received base low calorific value of the coal sample are determined by the standard method. The values of the constants A and B are obtained by linear regression with the sum X of the total moisture and the received base ash content as the abscissa and the received base low calorific value Y as the ordinate.

[0018] S3. In actual testing, only one of the received base ash content and the received base low calorific value needs to be measured under the premise of measuring the total moisture, and the other parameter not directly measured is calculated by combining the theoretical formula.

[0019] For example, in combination with water spectroscopy rapid determination, ash spectroscopy analysis technology and the application of transformation of coal mechanical automatic sampling machine, when the coal is crushed to ≤6 mm particle size, the online total moisture tester is used to obtain real-time total moisture data; when the coal is crushed to ≤6 mm or ≤3 mm particle size, the online ash tester is used to obtain real-time ash data; the real-time total moisture and received base ash data are input into the formula Y=AX+B, and the received base low calorific value is dynamically calculated in real time.

[0020] With the online real-time coal received base low calorific value, total moisture and received base ash data parameters, a batch coal quality fluctuation curve can be generated, and the uniformity of incoming coal or the stability of the calorific value of the furnace can be determined; the average value of the continuous determination data is used as the batch coal quality parameter result, which is used as the production and operation calculation data; and the coal blending and calorific value control in the production process of the coal-fired or chemical raw coal is guided.

[0021] Using the theoretical calculation formula established in the embodiment, the received base low calorific value or the received base ash can be calculated and obtained under the condition of only determining the total moisture and the received base ash, or only determining the total moisture and the received base low calorific value. The error of the calculation result and the actual measured value meets the standard method requirement: the total moisture, the received base ash and the received base low calorific value data determined are substituted into the Y=AX+B theoretical calculation formula, if the error of the calculation result and the actual measured value exceeds the standard method requirement range, it is determined that the received base ash and the received base low calorific value data of the coal sample determined are abnormal. The deviation of the calculated received base low calorific value and the actual measured value is ≤72 kcal / kg, the deviation of the ash content (Aad%) of the coal sample is less than the reproducibility requirement value of the corresponding different concentration range of the national standard GBT30732, when Aad%<15%, the deviation is ≤0.3%; when 15%≤Aad%≤30%, the deviation is ≤0.5%; when Aad%>30%, the deviation is ≤0.7%. Generally, the absolute value average of the ash content deviation of multiple batches of coal samples of the same mine is less than 0.27%, and the absolute value average of the ash content deviation of multiple batches of coal slime samples is less than 0.34%.

[0022] Using the theoretical calculation formula, the mine party, the coal research institute or the user only needs to perform pre-determination of the total moisture, ash content and calorific value of a certain coal type, and then the A and B constants of the calculation formula can be obtained. Other users or daily detection do not need to perform instrument determination of the ash content or the calorific value to calculate the data, which greatly saves the equipment, energy, manpower and time resource cost.

[0023] With the theoretical calculation formula, combined with water spectroscopy rapid determination, ash spectroscopy analysis technology and the transformation application of coal mechanical automatic sampling machine, online total water determination can be carried out when the coal sample is broken to 6 mm, online ash determination can be carried out when the coal sample is broken to 6 mm or 3 mm, and online calorific value calculation can be realized. With the online real-time coal calorific value, moisture and ash data parameters, the uniformity of incoming coal or the fluctuation of the calorific value of the furnace can be judged by the batch coal determination curve, which can more effectively guide production, and the average value measured can be used as the batch project parameter result and the production and operation calculation data.

[0024] A simple quantitative relationship Y = AX + B between the coal quality determination parameters of the mineral species established by the embodiment can be applied for calculation instead of determination, and the instruments and methods conforming to the national and international standards for determining total water, ash and calorific value can be used to meet the requirements without additional investment; 30%-50% of the determination cost of 3 items can be saved, the work efficiency can be improved by 30%-50%, and there is a prospect of technical application space breakthrough.

[0025] It should be noted that the total moisture, received base ash and received base low calorific value parameter data of the organic product with stable composition structure also conform to the Y = AX + B theoretical calculation formula.

[0026] The embodiment will be further described below in combination with specific mineral coal quality.

[0027] Table 1 Theoretical calculation formula of different coal species

[0028] Table 2

[0029] As can be seen from the above, with the theoretical calculation formula established by the embodiment, the received base low calorific value or the received base ash can be calculated and obtained under the condition of only determining the total moisture or the received base ash, or only determining the total water and the received base low calorific value, the calculation result meets the standard method requirement, the deviation of the calculated received base low calorific value from the measured value is ≤72 kcal / kg, the ash content (Aad%) of the coal sample has a deviation less than the reproducibility requirement value of the national standard GBT 30732 corresponding to different concentration ranges, when Aad% < 15%, the deviation is ≤0.3%; when 15%≤ Aad% ≤30%, the deviation is ≤0.5%; when Aad% > 30%, the deviation is ≤0.7%. Generally, the absolute value average of the ash content deviation of multiple batches of coal samples of the same mineral species is less than 0.27%, and the absolute value average of the ash content deviation of multiple batches of coal slurry samples is less than 0.34%.

[0030] Any combination of the technical features in the above-described embodiments can be made, and for the sake of brevity, not all possible combinations are described, however, as long as there is no conflict, any combination of the technical features should be considered within the scope of the present disclosure.

[0031] The above-described embodiments only express several embodiments of the present application, which are described in a more specific and detailed manner, but should not be understood as limiting the scope of the patent. It should be noted that for ordinary skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, which are all within the scope of protection of the present application. Therefore, the scope of protection of the present patent should be subject to the appended claims.

Claims

1. A method of calculating a coal heat value, characterized by, It comprises the following steps: S1. Establishing a theoretical calculation formula of the received base low heat value Y and the sum of the total moisture and the received base ash X: Y=AX+B, wherein A and B are constants; S2. Determining the values of the constants A and B by linear regression fitting based on the total moisture, the received base ash and the received base low heat value of the target coal sample determined by the standard method; S3. In actual detection, only one of the received base ash and the received base low heat value needs to be determined under the premise of determining the total moisture, and the other parameter not directly determined is calculated by the theoretical formula.

2. The coal heat value calculation method according to claim 1, characterized by, In step S2, the determination method of the constants A and B comprises: Performing standard method determination of the total moisture, the received base ash and the received base low heat value of multiple batches of coal samples of the same mine; Taking the sum of the total moisture and the received base ash X as the abscissa and the received base low heat value Y as the ordinate to perform linear regression and obtain the values of the constants A and B.

3. The coal heat value calculation method according to claim 1, characterized by, In step S3, when the coal is crushed to a particle size of ≤6 mm, the total moisture data is obtained in real time by using an online total moisture tester; When the coal is crushed to a particle size of ≤6 mm or ≤3 mm, the received base ash data is obtained in real time by using an online ash tester; The real-time obtained total moisture and received base ash data are input into the formula Y=AX+B to obtain the received base low heat value in real time and dynamically.

4. The coal calorific value calculation method according to claim 3, characterized by, The obtained received base low heat value, total moisture and received base ash data are used for: Generating a batch coal quality fluctuation curve to judge the uniformity or heat value stability of incoming coal; Taking the average value of the continuous determination data as the batch coal quality parameter result; Guiding the coal blending and heat value control in the production process of coal-fired or chemical raw coal.

5. The coal heat value calculation method according to claim 3, characterized by, The online total moisture determination adopts light wave rapid determination technology, and the online ash determination adopts spectrum analysis technology.

6. The coal heat value calculation method according to claim 1, characterized by, The theoretical calculation formula is used to judge whether the coal sample determination data is normal, specifically: The total moisture, received base ash and received base low heat value data determined are substituted into the Y=AX+B theoretical calculation formula, and if the error of the calculation result and the actual determination value exceeds the range required by the standard method, it is judged that the received base ash and received base low heat value data of the coal sample determination are abnormal.

7. The coal heat value calculation method of claim 1, wherein, The deviation of the calculated received base low heat value and the measured value is ≤72 kcal / kg, and the coal sample ash deviation meets the requirements of the national standard GBT 30732.

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