A rapid method for industrial analysis of coal and coke

Abstract

The present invention relates to a method for rapidly performing industrial analysis of coal and coke, which includes the steps of: 1) setting temperature and atmosphere control levels in the industrial analysis process using a thermogravimetric analyzer; 2) placing an empty crucible in the thermogravimetric analyzer to conduct a blank control experiment; 3) weighing the experimental sample and loading it into the crucible; 4) placing the crucible containing the sample in the thermogravimetric analyzer to conduct experiments for the experimental group; 5) processing the experimental results and automatically subtracting the results of the blank control experiment to obtain the thermogravimetric analysis results for the sample itself; and 6) calculating and analyzing the contents of moisture, ash, volatile matter, and fixed carbon to obtain the industrial analysis results. This method has the advantages of enabling rapid industrial analysis of organic carbon materials such as coal, coke, and biomass, allowing repeated experiments to be performed in a short period of time, and achieving more reliable results due to more accurate mass measurement by the thermogravimetric analyzer, higher sensitivity of the balance, more accurate temperature control, and smaller error.

Description

[Technical Field]

[0001] The present invention relates to the field of coal and coke analysis, and in particular to a method for rapid industrial analysis of coal and coke. [Background technology]

[0002] The specific procedure of the Chinese national standard GB / T 2001-2013 used in conventional coke industrial analysis measurement methods is as follows. In the conventional measurement method, a predetermined amount of air-dried sample is weighed, placed in an oven at 105–110°C, and dried in an air stream until the mass becomes constant. The moisture content (%) of the coal sample is calculated from the mass loss of the coal sample. For the volatile content test, a predetermined amount of air-dried sample is weighed, placed in a ceramic crucible with a lid, and heated at 900±10°C for 7 minutes while blocking air. The volatile content of the coal sample is calculated by subtracting the moisture content calculated from the mass loss (%) relative to the mass of the coal sample. For the ash content test (rapid ashing method), the sample is gradually transferred from the outside of the furnace into a muffle furnace preheated to 815±10°C and calcined for 1 hour. The ash content is calculated as the percentage of the mass of the residue relative to the mass of the coal sample (%). Because the test conditions for ash content and volatile matter are significantly different, the tests for ash content and volatile matter are usually performed independently and sequentially, which takes a long time and results in low work efficiency, making it impossible to meet the demands for rapid online analysis in industrial sites.

[0003] Among the prior art, Patent Publication No. CN1514226A discloses a discontinuous measurement method and analytical device for industrial analysis of coal-based materials. The test furnace is divided into a cylindrical furnace and a well furnace. In the analytical device, the cylindrical furnace has a built-in sample supply rod that can be raised and lowered, and the well furnace has a built-in sample mounting stage that can be raised and lowered and rotated to hold the sample crucible, as well as an electronic balance. A computer is connected to the sample supply rod, the lifting and rotating mechanism for the sample mounting stage, and the electronic balance via a control circuit to control their operation, and is also connected to the heating resistors and thermocouples in both furnaces to control the furnace temperature. The measurement method involves placing a coal sample crucible on a sample holder, heating it in a well furnace with nitrogen gas flow at 105-110°C until the mass becomes constant, automatically calculating the moisture content (%), then switching to oxygen gas and heating it at 815°C + / -10°C until the mass becomes constant, calculating the ash content. Next, the crucible for measuring volatile matter and the coal sample are loaded into a cylindrical furnace at 900°C ±10°C and heated for 7 minutes to measure the volatile matter content. This technical method allows for automatic measurement of four industrial analysis indicators of organic matter such as coal and coke: moisture, ash content, volatile matter, and fixed carbon. The measurement process does not require supervision, is fast, and highly efficient. However, this method is complicated because the furnace bodies are connected, making it difficult to ensure atmosphere control, and the ash and volatile matter measurement areas are interchanged.

[0004] Patent Publication No. CN101377483A discloses an industrial coal analysis method for simultaneously measuring the ash and volatile content of air-dried coal samples in the same high-temperature furnace to obtain ash and volatile content values. The specific steps are as follows: Prior to testing, the high-temperature furnace is heated to 400-500°C and maintained at that temperature. The air-dried coal sample for ash content measurement is then loaded into the high-temperature furnace, where it is heated to 920±10°C at a predetermined rate of 20-30°C / min and maintained at that temperature; the air-dried coal sample for volatile content measurement is then loaded into the high-temperature furnace where the ash content test is being performed. The high-temperature furnace temperature, which was lowered upon sample loading, is then returned to 900±10°C within three minutes and maintained at that temperature; and after the test of the air-dried coal sample for volatile content measurement is completed and removed from the high-temperature furnace, the furnace temperature is either maintained at that temperature or the high-temperature furnace temperature is lowered to 815±10°C at a predetermined rate of 10-15°C / min and maintained at that temperature until the ash content test is completed. An automated analyzer was used in the experiment, significantly shortening the total test time compared to conventional methods. However, the entire process, from weighing, loading, heating, and removing the sample to weighing after the test, still requires time and manpower, so there is a need for a faster and more accurate industrial analytical measurement method. Summary of the Invention [Problem to be solved by the invention]

[0005] The purpose of this invention is to provide a method for rapid industrial analysis of coal and coke. By using a thermogravimetric analyzer (TGA), industrial analysis of organic carbon samples such as coal and coke can be performed more sensitively and accurately. By controlling the temperature changes and reaction atmosphere in the process, the moisture, ash, volatile matter, and fixed carbon contents of the sample can be analyzed, shortening the overall experimental time, improving work efficiency, and reducing various errors caused by human operation. Furthermore, the experimental equipment is highly accurate, making it possible to meet the demand for rapid analysis in industrial sites. [Means for solving the problem]

[0006] In order to achieve the above object, the present invention employs the following technical means. A quick method for industrial analysis of coal and coke, including the following steps: 1) Setting the temperature control system and atmosphere control system in the industrial analysis process using a thermogravimetric analyzer; Temperature control: increase the temperature to 105±5°C at a rate of 10-20°C / min and keep at this temperature for 10-15 minutes, then increase the temperature to 900±5°C at a rate of 10-20°C / min and keep at this temperature for 30-60 minutes, then decrease the temperature to 815±5°C at a rate of 10-20°C / min and keep at this temperature for 30-60 minutes, then decrease the temperature to 25±5°C at a rate of 10-20°C / min; Atmosphere control system: At the start of the experiment, nitrogen was introduced at a flow rate of 60-100 ml / min. When the temperature dropped to 815±10°C, the gas was switched to air at a flow rate of 60-100 ml / min. When the temperature reached 815±10°C, the gas was switched back to nitrogen. 2) placing an empty crucible into the thermogravimetric analyzer to perform a blank control experiment; 3) weighing the experimental sample and placing it in the crucible; 4) placing the crucible containing the sample into a thermogravimetric analyzer to perform the experiments of the experimental group; 5) Data processing the experimental results and automatically subtracting the results of the blank control experiment to obtain the thermogravimetric analysis results of the sample itself; and 6) A step of calculating and analyzing the contents of moisture, ash, volatile matter, and fixed carbon to obtain the results of proximate analysis.

[0007] The crucible is made of Al2O3. The test sample is an organic carbonaceous material, and the particle size of the test sample is 100 to 400 μm. The organic carbonaceous material is coal and / or coke. Regarding step 4), record the net mass of the sample before conducting the experiment, and perform the experiment according to the temperature control system and atmosphere control system set in step 1). The temperature control and atmosphere control procedures employed in step 4) are the same as those in step 1). In step 5), the data of the experimental group are baseline corrected based on the results of the blank control group to obtain the thermogravimetric loss curve of the experimental sample.

[0008] The calculation in step 6) is as follows: After the start of the experiment, the temperature was raised to 105±5°C and kept at this temperature for 10-15 minutes. In the first stage, the dehydration step, the relative proportion of water (M) was calculated when the weight loss stabilized;

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[0009] In the second stage, the temperature is raised to 900±5°C and kept at that temperature for 30-60 minutes to decompose the volatile matter. When the weight loss stabilizes, the relative proportion of the volatile matter (V) is calculated.

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[0010] In the third stage, the temperature is lowered to 815±5°C and kept at that temperature for 30-60 min in an air atmosphere to burn the fixed carbon. When the weight loss stabilizes, the relative proportion of fixed carbon (C) is calculated;

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[0011] After the experiment is completed, the relative ash percentage A is calculated.

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[0012] The present invention has the following advantageous effects compared to the prior art. The method of the present invention enables rapid industrial analysis of organic carbon materials such as coal, coke, and biomass, allowing repeated experiments in a short time. The method also improves the reliability of results due to the more accurate mass measurement by the thermogravimetric analyzer, the higher sensitivity of the balance, the more accurate temperature control, and the smaller error. Furthermore, it significantly reduces the measurement costs of industrial analysis (such as the energy consumption of crucibles and high-temperature muffle furnaces) by significantly saving human and material resources. This method is particularly suitable for simultaneously measuring and comparing a large number of samples.

[0013] The method of the present invention can shorten the overall experimental time, thereby significantly improving work efficiency and reducing various errors caused by human operation. Moreover, the experimental equipment is highly accurate, allowing it to meet the rapid analytical requirements of industrial sites. Since all calculation parameters are obtained by the equipment, errors caused by human operation are reduced and a foundation for coke evaluation is established. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram of temperature and atmosphere control settings. [Figure 2] FIG. 1 is a diagram for quickly performing industrial analysis of metallurgical coke fines in Example 1. [Figure 3] FIG. 1 is a diagram showing the rapid industrial analysis of coal powder in Example 2. [Figure 4] FIG. 1 is a diagram showing rapid industrial analysis of biomass in Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention will be described in detail below with reference to the drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments. As shown in Figure 1, the rapid method for industrial analysis of coal and coke is specifically carried out in the following steps: 1. Temperature control system in the process: After the program starts, the temperature is increased to 105±5°C at a rate of 10~20°C / min and kept at this temperature for 10~15 minutes, then increased to 900±5°C at a rate of 10~20°C / min and kept at this temperature for 30~60 minutes, then decreased to 815±3°C at a rate of 10~20°C / min and kept at this temperature for 30~60 minutes, then decreased to 25±5°C at a rate of 10~20°C / min. 2. Atmosphere setting during the process: At the start of the experiment, nitrogen is introduced in advance with a gas flow rate of 60-100 ml / min. When the temperature drops to 815°C, the gas is switched to air and the gas flow rate is set to the same flow rate of 60-100 ml / min. When the temperature is maintained at 815°C, the gas is switched back to nitrogen. 3. Blank control group: A blank control experiment was carried out using an empty Al2O3 crucible. 4. Experimental group: The experimental sample (organic carbonaceous material) was dried in air and crushed to 100-400 μm. 5-15 mg of sample powder was then weighed out and placed in the same Al2O3 crucible as the blank control group, ensuring that the sample volume did not exceed 2 / 3 of the crucible volume and that the sample spread to the bottom of the crucible (reducing the sample volume as much as possible while ensuring that the sample spreads to the bottom of the crucible). The crucible containing the sample was then placed in the thermogravimetric analyzer. 5. Conduct experiments on the experimental group according to the prescribed procedures using the same temperature and atmosphere regimes as those of the blank control group. 6. After the experiment is completed, the data of the experimental group are baseline corrected based on the results of the blank control group. 7. Calculation process: After the experiment begins, the first stage is the dehydration stage, and the relative proportion of moisture is calculated when the weight loss stabilizes; the second stage is the thermal decomposition stage of volatile matter, and the relative proportion of volatile matter is calculated when the weight loss stabilizes; the third stage is the combustion stage of fixed carbon in an air atmosphere, and the relative proportion of fixed carbon is calculated when the weight loss stabilizes; and the relative proportion of ash is calculated from the amount of solid remaining after the experiment is completed. [Example]

[0016] Example 1 The proximate analysis of metallurgical coke breeze from a coke manufacturing plant was carried out using a thermogravimetric analyzer, and the specific procedure was as follows: 1. Setting the temperature control system and atmosphere control system of the thermogravimetric analyzer Temperature control during the process: After the program started, the temperature was increased to 105°C at a rate of 15°C / min and maintained at this temperature for 10 minutes, then increased to 900°C at a rate of 15°C / min and maintained at this temperature for 30 minutes, then decreased to 815°C at a rate of 15°C / min and maintained at this temperature for 30 minutes, and then decreased to 25°C at a rate of 15°C / min. Atmosphere setting during the process: At the start of the experiment, nitrogen was introduced at a gas flow rate of 60 ml / min. When the temperature dropped to 815°C, the gas was switched to air at the same flow rate of 60 ml / min. When the temperature reached 815°C, the gas was switched back to nitrogen. 2. Blank control group: A blank control experiment was carried out using an empty Al2O3 crucible of a predetermined volume. 3. Experimental group: The coke was dried in air and crushed to 200 μm. 10 mg of sample powder was weighed out and placed in the Al2O3 crucible used for the blank control group so that the sample volume did not exceed two-thirds of the crucible volume and the sample was spread at the bottom of the crucible. The crucible containing the sample was then placed in the thermogravimetric analyzer. 4. The same temperature and atmosphere control systems as those used for the blank control group were used, and the net mass of the sample (10.85 mg) was recorded before the start of the experiment, and the experiment was carried out according to the specified procedures. 5. After the experiment was completed, the data of the experimental group were baseline corrected based on the results of the blank control group, and the results shown in Figure 2 were obtained. 6. Calculation process: After extracting and calculating the data for each stage, the mass percentages were: moisture 1.84%, ash 13.18%, volatile matter 5.6%, and fixed carbon 79.35%.

[0017] Example 2 The proximate analysis of the coal powder was carried out using a thermogravimetric analyzer, and the specific procedure was as follows. 1. Setting the temperature control system and atmosphere control system of the thermogravimetric analyzer Temperature control during the process: After the program started, the temperature was increased to 105°C at a rate of 15°C / min and maintained at this temperature for 10 minutes, then increased to 900°C at a rate of 15°C / min and maintained at this temperature for 30 minutes, then decreased to 815°C at a rate of 15°C / min and maintained at this temperature for 30 minutes, and then decreased to 25°C at a rate of 15°C / min. Atmosphere setting during the process: At the start of the experiment, nitrogen was introduced at a gas flow rate of 60 ml / min. When the temperature dropped to 815°C, the gas was switched to air at the same flow rate of 60 ml / min. When the temperature reached 815°C, the gas was switched back to nitrogen. 2. Blank control group: A blank control experiment was carried out using an empty Al2O3 crucible of a predetermined volume. 3. Experimental group: The coke was dried in air and crushed to 200 μm. Approximately 5 mg of sample powder was weighed out and placed in the Al2O3 crucible used for the blank control group so that the sample volume did not exceed two-thirds of the crucible volume and the sample was spread at the bottom of the crucible. The crucible containing the sample was then placed in the thermogravimetric analyzer. 4. The same temperature and atmosphere control systems as those used for the blank control group were used, and the net mass of the sample, 6.16 mg, was recorded before the start of the experiment, and the experiment was carried out according to the specified procedures. 5. After the experiment was completed, the data of the experimental group were baseline corrected based on the results of the blank control group, and the results shown in Figure 3 were obtained. 6. Calculation process: After extracting and calculating the data for each stage, the mass percentages were: moisture 1.14%, ash 8.45%, volatile matter 19.67%, and fixed carbon 70.73%.

[0018] Example 3 Using a thermogravimetric analyzer, industrial analysis measurements of the biomass charcoal treated by the hydrothermal method were carried out, and the specific procedures were as follows. 1. Setting the temperature control system and atmosphere control system of the thermogravimetric analyzer Temperature control during the process: After the program started, the temperature was increased to 105°C at a rate of 15°C / min and maintained at this temperature for 10 minutes, then increased to 900°C at a rate of 15°C / min and maintained at this temperature for 30 minutes, then decreased to 815°C at a rate of 15°C / min and maintained at this temperature for 30 minutes, and then decreased to 25°C at a rate of 15°C / min. Atmosphere setting during the process: At the start of the experiment, nitrogen was introduced at a gas flow rate of 60 ml / min. When the temperature dropped to 815°C, the gas was switched to air at the same flow rate of 60 ml / min. When the temperature reached 815°C, the gas was switched back to nitrogen. 2. Blank control group: A blank control experiment was carried out using an empty Al2O3 crucible of a predetermined volume. 3. Experimental group: Biomass charcoal was dried in air and crushed to 200 μm. Approximately 6 mg of sample powder was weighed out and placed in the Al2O3 crucible used for the blank control group so that the sample volume did not exceed two-thirds of the crucible volume and the sample was spread at the bottom of the crucible. The crucible containing the sample was then placed in the thermogravimetric analyzer. 4. The same temperature and atmosphere control systems as those used for the blank control group were used, and the net mass of the sample (6.35 mg) was recorded before the start of the experiment, and the experiment was carried out according to the specified procedures. 5. After the experiment was completed, the data of the experimental group were baseline corrected based on the results of the blank control group, and the results shown in Figure 4 were obtained. 6. Calculation process: After extracting and calculating the data for each stage, the mass percentages were: moisture 1.11%, ash 2.68%, volatile matter 43.00%, and fixed carbon 52.22%.

Claims

1. A method for rapidly performing industrial analysis of coal and coke, comprising the steps of: 1) setting the temperature control accuracy and atmosphere control accuracy in the industrial analysis process using a thermogravimetric analyzer; Temperature control: increase the temperature at a rate of 10-20°C / min to 105±5°C, and maintain this temperature for 10-15 minutes. Then increase the temperature at a rate of 10-20°C / min to 900±5°C, and maintain this temperature for 30-60 minutes. Then decrease the temperature at a rate of 10-20°C / min to 815±5°C, and maintain this temperature for 30-60 minutes. Then decrease the temperature at a rate of 10-20°C / min to 25±5°C; Atmosphere control: At the start of the experiment, nitrogen was introduced at a flow rate of 60-100 ml / min. When the temperature dropped to 815±10°C, the gas was switched to air at a flow rate of 60-100 ml / min. When the temperature reached 815±10°C, the gas was switched back to nitrogen. 2) placing an empty crucible into the thermogravimetric analyzer to perform a blank control experiment; 3) weighing the experimental sample and placing it in the crucible; 4) placing the crucible containing the sample into a thermogravimetric analyzer to perform the experiments of the experimental group; 5) Data processing of the experimental results and automatically subtracting the results of the blank control experiment to obtain the thermogravimetric analysis results of the sample itself; and 6) A step of calculating and analyzing the contents of moisture, ash, volatile matter, and fixed carbon to obtain the results of proximate analysis.

2. The crucible is made of Al ２ O ３ 2. The method for rapidly carrying out industrial analysis of coal and coke according to claim 1, wherein the crucible is a crucible of 1000 kJ / cm2.

3. 2. The method for rapidly performing industrial analysis of coal / coke according to claim 1, wherein the experimental sample is an organic carbonaceous material and has a particle size of 100 to 400 μm.

4. 4. The method for rapid industrial analysis of coal and coke according to claim 3, wherein the organic carbonaceous material is coal and / or coke.

5. 2. The method for rapid industrial analysis of coal / coke according to claim 1, wherein, in step 4), the net mass of the sample is recorded before the experiment, and the experiment is carried out in accordance with the temperature control regime and atmosphere control regime set in step 1).

6. 2. The method for rapid industrial analysis of coal and coke according to claim 1, wherein the temperature control and atmosphere control adopted in step 4) are the same as those in step 1).

7. 2. The method for rapid industrial analysis of coal and coke according to claim 1, wherein in step 5), the data of the experimental group are baseline corrected based on the results of the blank control group to obtain the thermogravimetric loss curve of the experimental sample.

8. 2. The method for rapid industrial analysis of coal and coke according to claim 1, wherein the calculation in step 6) is as follows: After the start of the experiment, the temperature was raised to 105±5°C and kept at this temperature for 10 to 15 minutes. In the first stage, which is the dehydration stage, the relative proportion of water, M, was calculated when the weight loss stabilized; [Equation 1] [In formula (1), m １ (unit: g) is the mass of the experimental sample recorded before the start of the experiment, and m ２ (Unit: g) is the mass of the experimental sample recorded when the weight loss stabilizes in the first stage.] In the second stage, the temperature is raised to 900±5°C and kept at that temperature for 30 to 60 minutes to thermally decompose the volatile matter. When the weight loss stabilizes, the relative proportion V of the volatile matter is calculated; [Equation 2] [In formula (2), m ３ (Unit: g) is the mass of the experimental sample recorded when the weight loss stabilizes in the second stage.] In the third stage, the temperature is lowered to 815±5°C and the temperature is maintained for 30 to 60 minutes in an air atmosphere to burn the fixed carbon. When the weight loss becomes stable, the relative proportion of fixed carbon (C) is calculated; [Equation 3] [In formula (3), m ４ (Unit: g) is the mass of the experimental sample recorded when the weight loss stabilizes in the third stage.] After the experiment is completed, the relative ash percentage A is calculated. [Equation 4] [In formula (4), m ５ (unit: g) is the mass of the residual solid recorded at the end of the experiment.]

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