A sample rapid combustion test device and test method

Abstract

The present invention relates to a sample rapid combustion test device and test method, first ignite a sample of known initial mass; calculate the calorific value of the sample based on a temperature rise curve and a calorific value fitting formula, then obtain the element content corresponding to the sample based on the absorbance of the infrared detected sample and the corresponding element content fitting formula, and finally obtain the ash value of the sample based on the ash value fitting formula; then calculate the comparison calorific value by fusion comparison fitting formula, calculate the difference between the comparison calorific value and the calorific value, and judge whether the difference meets the preset threshold. Using this method, multiple parameters of the sample can be quickly measured in an integrated manner, avoiding the need to switch multiple devices for separate testing during testing, reducing the cost required for testing, and avoiding the need to re-sample each time the device is switched, effectively simplifying the test process, being able to quickly obtain test results, shortening the test cycle, and further adding a post-test fusion comparison technology to effectively improve the test accuracy and avoid abnormal errors.

Description

Technical Field

[0001] The invention relates to the field of coal industry testing, and in particular to a sample rapid combustion testing device and a testing method. Background Art

[0002] When testing combustible materials such as coal, ore, biomass, and medicines, it is necessary to test the various constituent elements, calorific value, and ash content of the samples. For example, for coal, it is necessary to quickly detect the calorific value, ash content, C, H, S and other component indicators before it is burned in the furnace for power generation to achieve the coal ratio before entering the furnace, to ensure that the maximum combustion calorific value efficiency of different coal ratios is exerted to control costs and increase power generation output, and to ensure that tail gas emissions, combustion ash, and coking meet the requirements of regulations. At present, the coal industry mostly uses traditional testing methods. Usually, special equipment is required to test different parameters of samples, but this process may require that the samples be divided into multiple parts for sampling, sample drying, and powdering, and the instruments must be calibrated separately, which increases equipment costs and time costs. In addition, due to the switching between multiple devices, the operation process is cumbersome and the test process is long, which cannot meet the rapid test results, and is not conducive to the timely realization of the actual needs of rapid coal blending and combustion. Summary of the invention

[0003] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a sample rapid combustion test device and a test method, which solves the problems of the prior art in the process of detecting multiple parameter indicators of coal, such as complex operating steps and the need to switch different equipment, resulting in low efficiency and high cost.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A sample rapid combustion test method comprises the following steps:

[0006] Step S1, obtaining the initial mass of the sample and igniting the sample;

[0007] Step S2, obtaining a temperature rise curve of the sample during the combustion process from the start of combustion to the completion of combustion and reaching temperature rise equilibrium, and calculating the calorific value of the sample based on the temperature rise curve;

[0008] Step S3, after the temperature rise is balanced, the mixed gas generated by the combustion is discharged and the absorbance of the mixed gas is obtained by infrared detection, and the absorbance is substituted into the corresponding element content fitting formula to obtain the element content corresponding to the sample, and the elements include at least C, H and S;

[0009] Step S4, obtaining the residual mass of the sample after complete combustion, calculating the mass ratio of the residual mass of the sample to the initial mass, and calculating the air-dry basis mass ratio of the sample based on the mass ratio, substituting the air-dry basis mass ratio into the ash value fitting formula to obtain the ash value of the sample;

[0010] Step S5, substituting the C element content into the fusion comparison fitting formula to calculate the comparison calorific value, performing a difference calculation between the comparison calorific value and the calorific value, and judging whether the difference meets a preset threshold;

[0011] If not, it is judged as an abnormal value and needs to return to step S1 for retesting.

[0012] Furthermore, the fusion alignment fitting formula construction step is also included:

[0013] Calculate the calorific value Q of the reference sample based on the temperature rise curve i , based on infrared detection, the C element content Z of the reference sample is obtained ci Repeat the above steps at least 10 times to obtain the calorific value Q of at least 10 groups of reference samples i and C element content Z ci , and substitute them into the fusion alignment fitting formula Perform fitting to determine m and n, and then determine the fusion comparison fitting formula to calculate the comparison calorific value Q1.

[0014] Furthermore, the step S2 comprises the following steps:

[0015] Step S 21 , obtain the initial temperature before the sample burns;

[0016] Step S 22 2. Obtain the time when the sample starts to burn and heat up to the temperature rise equilibrium according to the temperature rise curve, and calculate the effective temperature rise area. The effective temperature rise area is obtained based on the following formula:

[0017]

[0018] Where: S t —Total temperature rise area; T t —Real-time temperature, unit: °C; t1—Start time of sample combustion, unit: s; t2—Time from complete combustion to temperature rise equilibrium, unit: s; S1—Bottom area; T 初 —initial temperature, unit: °C; S2—effective temperature rise area; i—constant;

[0019] Step S 23 , Substitute the calculated effective temperature rise area into the calorific value fitting formula to obtain the calorific value of the sample.

[0020] Furthermore, the method also includes the step of constructing a calorific value fitting formula:

[0021] The initial temperature is obtained before the reference sample is burned, and the mass, water content on an air-dry basis, hydrogen value and higher heating value on a dry basis of the reference sample are known;

[0022] The air-dry basis higher calorific value of the reference sample is calculated based on the air-dry basis higher calorific value and air-dry basis moisture content of the reference sample, and the air-dry basis lower calorific value Q of the reference sample is calculated based on the air-dry basis higher calorific value of the reference sample net.ad ;

[0023] Calculate the effective temperature rise area S2 based on the temperature rise curve;

[0024] Repeat the above steps at least 10 times to obtain the air-dried lower calorific value Q of at least 10 groups of reference samples. net.ad and effective temperature rise area S2, and substitute them into the calorific value fitting formula respectively , determine k, and then determine the calorific value fitting formula to calculate the calorific value Q2;

[0025] Substitute the effective temperature rise area S2 of at least 10 groups of reference samples into the calorific value fitting formula to calculate the calorific value Q2, and compare the calorific value Q2 with the air-dry basis lower calorific value Q net.ad Calculate the difference and determine whether the difference is within the preset range;

[0026] If not, the calorific value fitting formula needs to be rebuilt.

[0027] Furthermore, step S3 includes the following steps:

[0028] Step S 31 , turn on the infrared detection reference voltage value V0;

[0029] Step S 32 , after the temperature rise is balanced, the mixed gas produced by the combustion is discharged to the infrared detection unit;

[0030] Step S 33 , a voltage signal value V1 of the mixed gas detected by infrared in the infrared detection unit;

[0031] Step S 34 , obtaining the absorbance of the sample based on the voltage signal value and the reference voltage value;

[0032] Step S 35 , substituting the absorbance into the corresponding element content fitting formula to obtain the element content corresponding to the sample, wherein the elements include at least C, H and S.

[0033] Furthermore, it also includes the process of constructing the element content fitting formula:

[0034] Turn on the infrared detection reference voltage value V0; after the temperature rise is balanced, the mixed gas generated by the combustion of the reference sample is discharged to the infrared detection unit. The mass, moisture content and absolute element content of the reference sample are known;

[0035] The element content of the reference sample is calculated by the absolute element content, and the voltage signal value V1 of the mixed gas is detected by the infrared detection unit; the voltage signal value and the reference voltage value are substituted into the absorbance calculation formula Get the absorbance A of the reference sample u ;

[0036] Repeat the above steps at least 5 times to obtain the absorbance and the element content of at least 5 groups of reference samples;

[0037] Obtain the element content fitting formula of the quadratic polynomial fitting

[0038]

[0039] Where: Z-element content; A u —Absorbance, unit A; substitute the absorbance and the element content of at least 5 groups of reference samples into the element content fitting formula for fitting, determine the coefficients a, b and c in the element content fitting formula, and then determine the element content fitting formula.

[0040] Furthermore, a reverse calibration step is also included:

[0041] Turn on the infrared detection reference voltage value; ignite the sample and after the sample burns to the temperature rise equilibrium, discharge the mixed gas generated by the combustion of the counter-calibration sample to the infrared detection unit, and the standard value range of the mass and element content of the counter-calibration sample is known; detect the voltage signal value of the mixed gas through the infrared detection unit; obtain the absorbance of the counter-calibration sample based on the voltage signal value and the reference voltage value;

[0042] Repeat the above steps at least 3 times to obtain the absorbance of at least 3 groups of reverse calibration samples; substitute the absorbance into the element content fitting formula to obtain the element content, and substitute the element content and the sample weight into the unit mass element content calculation formula to calculate the unit mass element content; compare the unit mass element content with the known standard value range of the element content to determine whether the calculated unit mass element content is within the known standard value range of the element content;

[0043] If not, the element content fitting formula needs to be recalibrated and reconstructed.

[0044] Furthermore, the method also includes the step of constructing an ash value fitting formula:

[0045] Weigh the residual mass of the reference sample after complete combustion, wherein the initial mass and the standard ash value of the reference sample are known, and calculate the mass ratio based on the residual mass and the initial mass; calculate the air-dry basis mass ratio of the reference sample according to the reference conversion formula;

[0046] Repeat the above steps at least 10 times to obtain the air-to-dry basis mass ratios of at least 10 groups of reference samples;

[0047] Get the ash value fitting formula , where: Y ad —Ash value, unit: %X ad —air-dry basis mass ratio, unit: %; Substitute the standard ash values ​​and air-dry basis mass ratios of at least 10 groups of reference samples into the ash value fitting formula to determine A, B, and C, and then determine the ash value fitting formula;

[0048] Substituting the air-dry basis mass ratios of at least 10 groups of reference samples into the ash value fitting formula to calculate the ash value, performing difference calculation between the ash value and the standard ash value, and determining whether the differences are within a preset range;

[0049] If not, the ash value fitting formula needs to be rebuilt.

[0050] In order to achieve the above object, the present invention also adopts the following technical solutions:

[0051] A sample rapid combustion test device, comprising a combustion unit, a calorific value detection unit, an infrared detection unit, a weighing unit, a host computer system and an electronic control unit;

[0052] The combustion unit comprises a combustion chamber and an oxygen filling part, and the combustion chamber and the oxygen filling part can be connected in an on-off manner;

[0053] The calorific value detection unit is arranged inside the combustion unit, and is used to detect the temperature in the combustion chamber in real time when the sample is burning, and to provide a temperature rise curve of the sample during the combustion process from the beginning of combustion to the end of combustion until the temperature rise balance is reached;

[0054] The infrared detection unit can be connected to the combustion unit in an on-off manner, and is used to detect the absorbance of the mixed gas generated by the sample after the combustion is completed, and analyze the element content in the sample;

[0055] The weighing unit is located inside the combustion unit and is used to weigh the initial mass of the sample and the residual mass after complete combustion;

[0056] The host computer system is used to analyze and calculate the data in any one of the methods described;

[0057] The electronic control unit is communicatively connected with the combustion unit, the calorific value detection unit, the infrared detection unit, the weighing unit and the host computer system for running any one of the methods described.

[0058] In summary, compared with the prior art, the present invention has at least the following beneficial effects:

[0059] The invention relates to a method for testing rapid combustion of a sample. First, the initial mass of the sample is obtained and the sample is ignited. Then, a temperature rise curve of the sample in a combustion process from the beginning of combustion to the completion of combustion and reaching temperature rise equilibrium is obtained, and the calorific value of the sample is calculated based on the temperature rise curve. After the temperature rise equilibrium is reached, a mixed gas generated by the combustion is discharged and the absorbance of the mixed gas is obtained through infrared detection, and the absorbance is substituted into a corresponding element content fitting formula to obtain the corresponding element content of the sample. The residual mass of the sample after complete combustion is obtained, and the air-dry basis mass ratio of the sample is calculated therefrom, and the air-dry basis mass ratio is substituted into an ash value fitting formula to obtain the ash value of the sample. Finally, the C element content is substituted into a fusion comparison fitting formula to calculate a comparison calorific value, and the comparison calorific value is difference-calorificated with the calorific value to determine whether the difference meets a preset threshold value. If not, it is determined to be an abnormal value and needs to be retested. This method can be used to quickly measure the calorific value, element content and ash value of the sample in an integrated manner, avoiding the need to switch multiple devices for separate testing when testing multiple parameters of a sample, reducing the equipment cost and labor cost required for the test, and avoiding the need to re-prepare samples every time the device is switched. It effectively simplifies the test process, is simple to operate, can quickly obtain test results, and shortens the test cycle. In addition, a post-test fusion comparison technology is further added to effectively improve the test accuracy and avoid abnormal errors.

[0060] The present invention also provides a sample rapid combustion test device corresponding to the above-mentioned sample rapid combustion test method, which has the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0062] Figure 1 The present invention provides a flow chart of the method for rapid combustion testing of samples.

[0063] Figure 2 It is a schematic diagram of the structure of a sample rapid combustion device provided in one embodiment of the present invention.

[0064] Figure 3 This is a schematic diagram of the temperature rise curve provided by the present invention.

[0065] Description of reference numerals:

[0066] 1. Combustion unit; 2. Calorific value detection unit; 3. Infrared detection unit; 4. Weighing unit; 5. Host computer system; 6. Electronic control unit. DETAILED DESCRIPTION

[0067] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0068] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0069] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] As attached Figure 1 As shown, a sample rapid combustion test method comprises the following steps:

[0071] Step S1, obtaining the initial mass of the sample and igniting the sample;

[0072] Step S2, obtaining a temperature rise curve of the sample during the combustion process from the start of combustion to the completion of combustion and reaching temperature rise equilibrium, and calculating the calorific value of the sample based on the temperature rise curve;

[0073] Step S3, after the temperature rise is balanced, the mixed gas generated by the combustion is discharged and the absorbance of the mixed gas is obtained by infrared detection, and the absorbance is substituted into the corresponding element content fitting formula to obtain the element content corresponding to the sample, and the elements include at least C, H and S;

[0074] Step S4, obtaining the residual mass of the sample after complete combustion, calculating the mass ratio of the residual mass of the sample to the initial mass, and calculating the air-dry basis mass ratio of the sample based on the mass ratio, substituting the air-dry basis mass ratio into the ash value fitting formula to obtain the ash value of the sample;

[0075] Step S5, substituting the C element content into the fusion comparison fitting formula to calculate the comparison calorific value, performing a difference calculation between the comparison calorific value and the calorific value, and determining whether the difference meets a preset threshold;

[0076] If not, it is judged as an abnormal value and needs to return to step S1 for retesting.

[0077] Specifically, the sample combustion in the present invention needs to be set in a closed and oxygen-rich container to facilitate the combustion of the sample and the measurement of the sample's composition and characteristic index values. First, the sample is ignited, and then the temperature change generated when the sample is ignited is used to draw a temperature rise curve. The calorific value of the sample is calculated by comprehensively calculating the mass of the burned sample and the temperature rise curve before and after the sample is burned; the mixed gas generated after the sample is completely burned is discharged into the infrared detection unit, so that the infrared detection unit detects the voltage signal value of the mixed gas and obtains the content of each element of the sample by calculation, and then infers its composition; after all the tests are completed, the residual mass of the sample after combustion is obtained, and the ash content of the sample is calculated by the mass ratio before and after combustion; finally, the detected calorific value parameters are verified through the fusion ratio step, and the mutual inspection of the calorific value and the C element content is realized, which effectively improves the test accuracy. This method integrates all the equipment required for testing various parameters into one, and there is no need to use multiple independent devices to test different parameters separately, avoiding the need to re-prepare samples every time the device is switched, reducing the equipment cost and labor cost required for testing, and effectively avoiding human errors and measurement errors between devices that are prone to occur when switching devices in traditional testing methods. It also effectively simplifies the testing process, is simple to operate, can quickly obtain test results, and shortens the testing cycle.

[0078] Furthermore, under the condition of constant combustion volume and the same pressure, the calorific value of the coal sample is proportional to the actual measured C element content. In order to improve the accuracy of the test method, after the test of each parameter of the sample is completed, a fusion comparison step is added, namely step S5, to realize the mutual inspection between the data through the C element content of the sample and the calculated comparison calorific value, thereby verifying the accuracy of the data. Therefore, before starting the fusion comparison calculation, the fusion comparison fitting formula should be constructed in advance, that is, the functional relationship between the parameters should be established through the reference sample, and finally the comparison calorific value of the sample should be determined by the measured C element content through the above functional relationship. In addition, the reference sample needs to have a known weight.

[0079] Therefore, this test method also includes the steps of constructing a fusion comparison fitting formula:

[0080] Calculate the calorific value Q of the reference sample based on the temperature rise curve i , based on infrared detection, the C element content Z of the reference sample is obtained ci Repeat the above steps at least 10 times to obtain the calorific value Q of at least 10 groups of reference samples i and C element content Z ci, and substitute them into the fusion alignment fitting formula Perform fitting to determine m and n, and then determine the fusion comparison fitting formula to calculate the comparison calorific value Q1.

[0081] It should be noted that in order to meet different detection requirements or ensure the accuracy of calculation results, users can also choose to update the fusion comparison fitting formula every time or at intervals, and adjust and optimize according to actual conditions, which is not limited here.

[0082] Specifically, when calculating the calorific value of the reference sample based on the temperature rise curve, step S2 includes the following steps:

[0083] Step S 21 , obtain the initial temperature before the sample burns;

[0084] Step S 22 2. Obtain the time from when the sample starts to burn and heat up to the temperature rise equilibrium according to the temperature rise curve, and calculate the effective temperature rise area. The effective temperature rise area is obtained based on the following formula:

[0085]

[0086] Where: S t —Total temperature rise area; T t —Real-time temperature, unit: °C; t1—Start time of sample combustion, unit: s; t2—Time from complete combustion to temperature rise equilibrium, unit: s; S1—Bottom area; T 初 —initial temperature, unit: °C; S2—effective temperature rise area; i—constant;

[0087] Step S 23 , Substitute the calculated effective temperature rise area into the calorific value fitting formula to obtain the calorific value of the sample.

[0088] Among them, the temperature rise curve is as shown in the attached Figure 3 As shown, the whole process of temperature change of the sample from the beginning of combustion to the complete combustion, i.e., the temperature rise equilibrium, is recorded. In addition, the constant i is the proportional coefficient related to the number of times of time and temperature acquisition, which is obtained according to the time frequency. The user can set the acquisition frequency by himself. For example, it is set to obtain the corresponding temperature at this time once every 0.2s. At this time, the total time of five acquisitions is 1s of combustion time, so the constant i is 5 at this time. The acquisition frequency is set by the user. The higher the acquisition frequency is set, the more accurate the measured temperature is.

[0089] Furthermore, before starting the calorific value calculation, a calorific value fitting formula should be constructed in advance, that is, the functional relationship between the calorific value and the effective temperature rise area should be established through reference samples, and finally the calorific value of the sample should be determined by substituting the effective temperature rise area obtained based on the temperature rise curve into the constructed calorific value fitting formula. Therefore, the steps of constructing the calorific value fitting formula include:

[0090] The initial temperature is obtained before the reference sample is burned, and the mass, water content on an air-dry basis, hydrogen value and higher heating value on a dry basis of the reference sample are known;

[0091] The air-dry basis higher calorific value of the reference sample is calculated based on the air-dry basis higher calorific value and air-dry basis moisture content of the reference sample, and the air-dry basis lower calorific value Q of the reference sample is calculated based on the air-dry basis higher calorific value of the reference sample net.ad ;

[0092] Calculate the effective temperature rise area S2 based on the temperature rise curve; repeat the above steps at least 10 times to obtain the air-dry basis lower calorific value Q of at least 10 groups of reference samples. net.ad and effective temperature rise area S2, and substitute them into the calorific value fitting formula respectively , determine k, and then determine the calorific value fitting formula to calculate the calorific value Q2;

[0093] Substitute the effective temperature rise area S2 of at least 10 groups of reference samples into the calorific value fitting formula to calculate the calorific value Q2, and compare the calorific value Q2 with the air-dry basis lower calorific value Q net.ad Calculate the difference and determine whether the difference is within the preset range;

[0094] If not, the calorific value fitting formula needs to be rebuilt.

[0095] Specifically, the lower calorific value Q of the reference sample on an air-dried basis is net.ad Calculated according to the conversion empirical formula related to coal quality:

[0096]

[0097] Where: Q gr.ad —Higher calorific value on air-dry basis;

[0098] Q gr.d —Higher calorific value on dry basis;

[0099] M ad —Water content on air-dried basis;

[0100] Q net.ad —Lower heating value on air-dry basis;

[0101] H—H element content in the sample.

[0102] It is worth noting that the preset range is set by the user according to the specific application scenario and different requirements for accuracy.

[0103] Specifically, when the element content of the reference sample is calculated based on infrared detection, step S3 includes the following steps:

[0104] Step S 31 , turn on the infrared detection reference voltage value V0;

[0105] Step S 32 , after the temperature rise is balanced, the mixed gas produced by the combustion is discharged to the infrared detection unit;

[0106] Step S 33 , a voltage signal value V1 of the mixed gas detected by infrared in the infrared detection unit;

[0107] Step S 34 , obtaining the absorbance of the sample based on the voltage signal value and the reference voltage value;

[0108] Step S 35 , Substitute the absorbance into the corresponding element content fitting formula to obtain the element content corresponding to the sample, and the elements include at least C, H and S.

[0109] The absorbance is given by the formula get.

[0110] Furthermore, before starting the calculation, the element content fitting formula should be constructed in advance through a quadratic polynomial, that is, the functional relationship between the element content and absorbance should be established through a reference sample, and finally the element content of the sample should be determined by the measured absorbance and the above element content fitting formula. In addition to C, H and S, if the user wants to obtain the content of other elements in the sample, it is also only necessary to construct the corresponding element content fitting formula, substitute the measured absorbance into the fitting formula, and then obtain the corresponding element content.

[0111] Therefore, this test method also includes the process of constructing the element content fitting formula:

[0112] Turn on the infrared detection reference voltage value V0; ignite the sample and after the sample burns to temperature rise equilibrium, discharge the mixed gas generated by the combustion of the reference sample to the infrared detection unit. The mass, moisture content and absolute element content of the reference sample are known; calculate the element content of the reference sample by the absolute element content, and detect the voltage signal value V1 of the mixed gas by the infrared detection unit; substitute the voltage signal value and the reference voltage value into the absorbance calculation formula Get the absorbance A of the reference sample u ;

[0113] Repeat the above steps at least 5 times to obtain the absorbance and element content of at least 5 groups of reference samples;

[0114] Obtain the element content fitting formula of the quadratic polynomial fitting

[0115]

[0116] Where: Z—element content, A u—Absorbance, unit A; substitute the absorbance and element content of at least 5 groups of reference samples into the element content fitting formula for fitting, determine the coefficients a, b and c in the element content fitting formula, and then determine the element content fitting formula.

[0117] That is, the element content fitting formula at least includes

[0118]

[0119] Where: Zc—C element content; a1, b1, c1 are obtained using the above element content fitting formula; and / or

[0120]

[0121] Where: Z H —H element content; a2, b2, c2 are obtained by using the above element content fitting formula; and / or

[0122]

[0123] Where: Z S —S element content; a3, b3, c3 are obtained using the above element content fitting formula. Similarly, if the user wants to test the content of other elements, the corresponding element content fitting formula is also constructed, and the measured absorbance is substituted to obtain the element content.

[0124] It should be noted that the element content test method provided by the present invention pre-builds a model that can be applied to all types of samples to calculate the content of different elements, and has strong versatility. In addition, in order to meet different detection requirements or ensure the accuracy of the calculation results, the user can also choose to update the required element content fitting formula every time or at intervals, and adjust and optimize according to actual conditions, which is not limited here.

[0125] Furthermore, in order to verify the accuracy of the element content fitting formula, the present invention also provides a reverse calibration method, which specifically includes the following steps:

[0126] Turn on the infrared detection reference voltage value; ignite the sample and after the sample burns to the temperature rise equilibrium, discharge the mixed gas generated by the combustion of the counter-calibration sample to the infrared detection unit, and the standard value range of the mass and element content of the counter-calibration sample is known; detect the voltage signal value of the mixed gas through the infrared detection unit; obtain the absorbance of the counter-calibration sample based on the voltage signal value and the reference voltage value;

[0127] Repeat the above steps at least 3 times to obtain the absorbance of at least 3 groups of reverse calibration samples; substitute the absorbance into the element content fitting formula to obtain the element content; substitute the element content and sample weight into the unit mass element content calculation formula to calculate the unit mass element content; compare the unit mass element content with the known standard value range of the element content to determine whether the calculated unit mass element content is within the known standard value range of the element content;

[0128] If not, the element content fitting formula needs to be recalibrated and reconstructed.

[0129] Furthermore, before calculating the ash value of the sample, a fitting formula for the ash value should be constructed in advance using a quartic polynomial, that is, a functional relationship between the ash value and the air-dry basis mass ratio should be established using a reference sample. Finally, the ash value of the sample should be determined by the air-dry basis mass ratio and calculated using the above ash value fitting formula.

[0130] Therefore, this test method also includes the process of constructing the ash value fitting formula:

[0131] Weigh the residual mass of the reference sample after complete combustion, wherein the initial mass and the standard ash value of the reference sample are known, and calculate the mass ratio based on the residual mass and the initial mass; calculate the air-dry basis mass ratio of the reference sample according to the reference conversion formula;

[0132] Repeat the above steps at least 10 times to obtain the air-to-dry basis mass ratios of at least 10 groups of reference samples;

[0133] Get the ash value fitting formula , where: Y ad —Ash value, unit: %X ad —Air-dry basis mass ratio, unit: %; Substitute the standard ash values ​​and air-dry basis mass ratios of at least 10 groups of reference samples into the ash value fitting formula to determine A, B, and C, and then determine the ash value fitting formula;

[0134] Substituting the air-dry basis mass ratios of at least 10 groups of reference samples into the ash value fitting formula to calculate the ash value, performing difference calculation between the ash value and the standard ash value, and determining whether the differences are within the preset range;

[0135] If not, the ash value fitting formula needs to be rebuilt.

[0136] Among them, according to the industrial analysis method of coal in GB / T212-2001, the mass ratio of the sample is obtained by the following formula:

[0137] X=m r / m×100%

[0138] Where, X is mass ratio, unit: %; m r—residual mass, in g; m—initial mass, in g.

[0139] According to the reference conversion formula between different coal quality samples, the air-dry basis mass ratio of the sample is obtained:

[0140]

[0141] Where, X d —Mass ratio of air-dry basis, unit: %; M ad —Water content on air-dry basis, in %.

[0142] In addition, it is worth mentioning that the preset range is set by the user according to the specific application scenario and different requirements for accuracy.

[0143] As attached Figure 2 As shown, in addition to the above-mentioned sample rapid combustion test method, the present invention also provides a sample rapid combustion test device based on the above-mentioned sample rapid combustion test method. The sample rapid combustion test device corresponds to the steps of the above-mentioned sample rapid combustion test method. The sample rapid combustion test device described below and the sample rapid combustion test method described above can be referenced to each other.

[0144] A sample rapid combustion test device, characterized in that it comprises a combustion unit 1, a calorific value detection unit 2, an infrared detection unit 3, a weighing unit 4, a host computer system 5 and an electronic control unit 6;

[0145] The combustion unit 1 comprises a combustion chamber and an oxygenating portion, and the combustion chamber and the oxygenating portion can be connected in an on-off manner;

[0146] The calorific value detection unit 2 is arranged inside the combustion unit 1, and is used to detect the temperature in the combustion chamber in real time when the sample is burning, and provide a temperature rise curve of the sample during the combustion process from the beginning of combustion to the end of combustion until the temperature rise balance is reached;

[0147] The infrared detection unit 3 can be connected to the combustion unit 1 in an on-off manner to detect the absorbance of the mixed gas generated by the sample after the combustion is completed and analyze the element content in the sample;

[0148] The weighing unit 4 is located inside the combustion unit 1 and is used to weigh the initial mass of the sample and the residual mass after complete combustion;

[0149] The host computer system 5 is used to analyze and calculate the data in any one of the methods;

[0150] The electronic control unit 6 is connected to the combustion unit 1, the calorific value detection unit 2, the infrared detection unit 3, the weighing unit 4 and the host computer system 6 for running any one of the methods.

[0151] Specifically, when the sample is tested, the sample is first placed in the combustion chamber. Since the oxygen filling part and the combustion chamber can be connected in an on-off manner, oxygen is introduced into the combustion chamber through the oxygen filling part before the sample is burned, so that the combustion chamber is rich in oxygen to facilitate the combustion of the sample. When the sample is burning, the calorific value detection unit 2 arranged inside the combustion chamber detects the temperature change in the combustion chamber from the beginning of combustion to the temperature rise equilibrium of complete combustion in real time, thereby obtaining the temperature rise curve of the sample combustion process. When the sample is burning, the infrared detection unit 3 is not connected to the combustion chamber, that is, the air outlet of the combustion chamber is closed. At this time, the infrared detection unit 3 synchronously detects the reference voltage value at this time. After the sample is burned, the air outlet of the combustion chamber is opened to allow the mixed gas generated by the sample combustion to enter the infrared detection unit 3 to detect the voltage signal value, and the signal record is transmitted to the upper computer system 5 to analyze and calculate it to obtain the element content and sample composition of the sample. When the element content of the sample is detected, the combustion chamber is vented and depressurized, and the residual mass of the sample after combustion is weighed using the weighing unit 4, and uploaded to the host computer system 5, which calculates the ash value in combination with the ash value test steps mentioned above. It is worth noting that the operation of the above method and the preset test process are all controlled by the electronic control unit. The use of this test device can quickly measure the calorific value, element content and ash value of the sample in an integrated manner, achieving a seamless connection from sample combustion to parameter detection, avoiding the need to switch multiple devices for separate testing when testing multiple parameters of a sample, and greatly improving the test efficiency. The operator does not need to switch between different devices, which reduces the complexity and time cost of the operation, and avoids the need to re-prepare the sample every time the device is switched, effectively simplifying the test process, simple operation, and can quickly obtain test results and shorten the test cycle.

[0152] The present invention is further described in detail below in conjunction with embodiments.

[0153] Example 1

[0154] (1) Pre-construction of calorific value fitting formula

[0155] 10 groups of reference samples were selected and placed in the combustion chamber respectively. The combustion chamber was filled with oxygen and then ignited. The effective temperature rise area was calculated based on the temperature rise curve during combustion. The air-dry basis higher calorific value was calculated based on the known dry basis higher calorific value, air-dry basis water content and H element content, and the air-dry basis lower calorific value was further calculated. The effective temperature rise area, dry basis higher calorific value, air-dry basis water content, H element content, air-dry basis higher calorific value and air-dry basis lower calorific value of the 10 groups of reference samples n1-n10 are shown in Table 1.

[0156] Substitute the effective temperature rise area and air-dry basis lower calorific value of each group of reference samples into the calorific value fitting formula , k is determined to be 7.38, and the calorific value fitting formula is determined as , substitute the effective temperature rise area into the determined calorific value fitting formula to calculate the calorific value; calculate the difference between the calorific value obtained from each group of reference samples and the lower calorific value on an air-dry basis, and judge whether the difference is within the preset range of -700-700J; the calorific value and difference of each group of reference samples are shown in Table 1.

[0157] Table 1

[0158]

[0159] (2) Pre-construction of the fitting formula for C element content

[0160] Select 9 groups of reference samples, place them in the combustion chamber respectively, fill the combustion chamber with oxygen and ignite it, and simultaneously turn on the infrared detection reference voltage value V0; after the sample burns to the temperature rise equilibrium, open the gas outlet to discharge the mixed gas generated by the combustion of the reference sample to the infrared detection unit;

[0161] Calculate the C element content of the reference sample based on the known absolute C element content and moisture value, and detect the voltage signal value V1 of the mixed gas through the infrared detection unit; substitute the voltage signal value and the reference voltage value into the absorbance calculation formula The absorbance Au of the reference sample is obtained; the weight, moisture value, reference voltage value, voltage signal value, absorbance, absolute C element content and C element content of 9 groups of reference samples s1-s9 are shown in Table 2.

[0162] Substitute the C element content and absorbance of each group of reference samples into the C element content fitting formula , determine a1=-30.0531880790, b1=138.5261546447, c1=-12.9337264208. Then determine the fitting formula of C element content: .

[0163] Table 2

[0164]

[0165] (3) Back-calibration verification of the C element content fitting formula

[0166] Ten groups of back-calibration samples v1-v10 with known standard value ranges were selected, and their absorbances were obtained, as shown in Table 3;

[0167] Substitute the absorbance of the reverse calibration sample into the C element content fitting formula in Example 2: , calculate the C content of each counter-calibration sample respectively, and then substitute the C content and sample weight into the calculation formula of C content per unit mass The calculated C element content per unit mass is obtained, and the calculated C element content per unit mass is compared with the known standard value range of the element content to determine whether the calculated C element content per unit mass is within the known standard value range of the C element content. The results are shown in Table 3.

[0168] Table 3

[0169]

[0170] (4) Pre-construction of ash value fitting formula

[0171] Select 10 groups of reference samples with known initial mass, air-dried basis moisture content and standard ash value, put them into the combustion chamber respectively, fill the combustion chamber with oxygen and ignite it. After complete combustion, weigh the residual mass of each group of reference samples after complete combustion through the weighing unit, calculate the mass ratio of each group of samples based on X=mr / m×100%, and use the benchmark conversion formula The air-dry basis mass ratio of each reference sample was calculated; the initial mass, residual mass, mass ratio, air-dry basis mass ratio and air-dry basis moisture content of the 10 reference samples m1-m10 are shown in Table 4. The air-dry basis mass ratio and standard ash value of each reference sample were substituted into the ash value fitting formula , determine A=0.076, B=-0.205, C=10.18. Then determine the ash value fitting formula as: .

[0172] The difference between the ash value obtained for each group of reference samples and the standard ash value is calculated, and it is determined whether the difference is within the preset range of ±1%; the ash value, standard ash value and difference of each group of reference samples are shown in Table 4.

[0173] Table 4

[0174]

[0175] (5) Pre-construction of fusion alignment fitting formula

[0176] Ten groups of reference samples whose calorific values ​​have been calculated through temperature rise curves and whose C element contents have been obtained based on infrared detection are selected. The calorific values ​​and C element contents of the ten groups of reference samples r1-r10 are shown in Table 5. Substitute the calorific value and C element content of each group of reference samples into the fusion comparison fitting formula , determine m=170.2, n=924.0. Then determine the fusion alignment fitting formula as: . Substitute the C element content into the fusion comparison fitting formula again , calculate the comparative calorific value Q1 of each group of reference samples respectively, calculate the difference between the comparative calorific value and the calorific value of each group of reference samples, and judge whether the difference meets the preset threshold value 1200. The results are shown in Table 5.

[0177] Table 5

[0178]

[0179] (6) Sample testing

[0180] Step S1, obtaining 0.5 g of sample, placing the sample in a combustion chamber, introducing oxygen into the combustion chamber through an oxygenating part, and igniting the sample;

[0181] Step S2, obtain the temperature rise curve of the sample during the combustion process from the beginning of combustion to the end of combustion until the temperature rise equilibrium is reached, calculate the effective temperature rise area of ​​the sample 1730.80433 based on the temperature rise curve, and calculate the effective temperature rise area of ​​the sample based on the calorific value fitting formula The calculated calorific value of the sample is 12,773.3359554;

[0182] Step S3, turn on the infrared detection reference voltage value of 2.916915, after the temperature rise is balanced, the mixed gas generated by the combustion is discharged to the infrared detection unit, and the voltage signal value of the infrared detection mixed gas in the infrared detection unit is 1.305978. Based on the voltage signal value 1.305978 and the reference voltage value 2.916915, the absorbance of the sample is 0.348988, and the absorbance 0.348988 is substituted into the C element content fitting formula The C content of the sample is 31.75%, and then the C content 31.75% and the sample weight 0.5g are substituted into the calculation formula of the C content per unit mass. The C content per unit mass is 63.5%;

[0183] Step S4, exhaust and depressurize the combustion chamber, use a weighing unit to weigh the residual mass of the sample after combustion to be 0.0382g, calculate the mass ratio of the residual mass of the sample to the initial mass to be 7.64%, and calculate the air-dry basis mass ratio of the sample to be 7.70% based on the mass ratio, and bring the air-dry basis mass ratio of 7.70% into the ash value fitting formula The ash value of the sample obtained was 13.10%.

[0184] Step S5: Substitute 63.5% of the C element content into the fusion comparison fitting formula The calculated comparison calorific value is 11731.7. The difference between the comparison calorific value 11731.7 and the calorific value 12,773.3359554 is calculated to be 1,041.6359554. It is judged that the difference is within the preset threshold of 1200. All the above measured data are accurate and valid.

[0185] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A sample rapid combustion test method, characterized in that: The following steps are involved: Step S1, obtaining the initial mass of the sample, and igniting the sample in a sealed and oxygen-enriched container; Step S2, obtaining the initial temperature before the sample burns, obtaining the temperature rise curve of the sample during the combustion process from the start of combustion to the end of combustion until the temperature rise balance is reached, obtaining the time from the start of combustion to the temperature rise balance according to the temperature rise curve, and calculating the effective temperature rise area, which is obtained based on the following formula: Where: S t —Total temperature rise area; T t —Real-time temperature, unit: °C; t1—Start time of sample combustion, unit: s; t2—Time from complete combustion to temperature rise equilibrium, unit: s; S1—Bottom area; T 初 —initial temperature, unit: °C; S2—effective temperature rise area; i—constant; Substitute the calculated effective temperature rise area into the calorific value fitting formula to obtain the calorific value of the sample; Wherein, the steps of constructing the calorific value fitting formula are: The initial temperature is obtained before the reference sample is burned, and the mass, air-dry basis water content, hydrogen value and dry basis higher calorific value of the reference sample are known; the air-dry basis higher calorific value of the reference sample is calculated based on the dry basis higher calorific value and air-dry basis water content of the reference sample, and the air-dry basis lower calorific value Q of the reference sample is calculated based on the air-dry basis higher calorific value of the reference sample net.ad , the air-dried basis lower calorific value Q net.ad According to the formula and Get: Where: Q gr.ad —Higher calorific value on air-dry basis; Q gr.d —Higher calorific value on dry basis; M ad —Water content on air-dried basis; Q net.ad — air-dry basis lower calorific value; H—H element content in the sample; calculate the effective temperature rise area S2 based on the temperature rise curve; repeat the above steps at least 10 times to obtain the air-dry basis lower calorific value Q of at least 10 groups of reference samples net.ad and effective temperature rise area S2, and substitute them into the calorific value fitting formula respectively , determine k, and then determine the calorific value fitting formula to calculate the calorific value Q2; substitute the effective temperature rise area S2 of at least 10 groups of reference samples into the calorific value fitting formula to calculate the calorific value Q2, and compare the calorific value Q2 with the air-dry basis lower calorific value Q net.ad Calculate the difference and determine whether the difference is within the preset range; if not, rebuild the calorific value fitting formula; Step S3, after the temperature rise is balanced, the mixed gas generated by the combustion is discharged and the absorbance of the mixed gas is obtained by infrared detection, and the absorbance is substituted into the corresponding element content fitting formula to obtain the element content corresponding to the sample, and the elements include at least C, H and S; Step S4, obtaining the residual mass of the sample after complete combustion, calculating the mass ratio of the residual mass of the sample to the initial mass, and calculating the air-dry basis mass ratio of the sample based on the mass ratio, substituting the air-dry basis mass ratio into the ash value fitting formula to obtain the ash value of the sample; Step S5, substituting the C element content into the fusion comparison fitting formula to calculate the comparison calorific value, performing a difference calculation between the comparison calorific value and the calorific value, and judging whether the difference meets a preset threshold; If not, it is judged as an abnormal value and needs to return to step S1 for retesting; The construction step of the fusion comparison fitting formula is as follows: based on the temperature rise curve, the calorific value Q of the reference sample is calculated. i , based on infrared detection, the C element content Z of the reference sample is obtained ci Repeat the above steps at least 10 times to obtain the calorific value Q of at least 10 groups of reference samples i and C element content Z ci , and substitute them into the fusion alignment fitting formula Perform fitting to determine m and n, and then determine the fusion comparison fitting formula to calculate the comparison calorific value Q1.

2. The sample rapid combustion test method according to claim 1, characterized in that: The step S3 comprises the following steps: Step S 31 , turn on the infrared detection reference voltage value V0; Step S 32 , after the temperature rise is balanced, the mixed gas produced by the combustion is discharged to the infrared detection unit; Step S 33 , a voltage signal value V1 of the mixed gas detected by infrared in the infrared detection unit; Step S 34 , obtaining the absorbance of the sample based on the voltage signal value and the reference voltage value; Step S 35 , substituting the absorbance into the corresponding element content fitting formula to obtain the element content corresponding to the sample, wherein the elements include at least C, H and S.

3. The sample rapid combustion test method according to claim 2, characterized in that: It also includes the process of constructing the element content fitting formula: Turn on the infrared detection reference voltage value V0; ignite the sample and after the sample burns to temperature rise equilibrium, discharge the mixed gas generated by the combustion of the reference sample to the infrared detection unit. The mass, moisture content and absolute element content of the reference sample are known; calculate the element content of the reference sample by the absolute element content, and detect the voltage signal value V1 of the mixed gas by the infrared detection unit; substitute the voltage signal value and the reference voltage value into the absorbance calculation formula Get the absorbance A of the reference sample u ; Repeat the above steps at least 5 times to obtain the absorbance and the element content of at least 5 groups of reference samples; Obtain the element content fitting formula of the quadratic polynomial fitting Where: Z-element content; A u —Absorbance, unit A; substitute the absorbance and the element content of at least 5 groups of reference samples into the element content fitting formula for fitting, determine the coefficients a, b and c in the element content fitting formula, and then determine the element content fitting formula.

4. The sample rapid combustion test method according to claim 3, characterized in that: A back-calibration step is also included: Turn on the infrared detection reference voltage value; ignite the sample and after the sample burns to the temperature rise equilibrium, discharge the mixed gas generated by the combustion of the counter-calibration sample to the infrared detection unit, and the standard value range of the mass and element content of the counter-calibration sample is known; detect the voltage signal value of the mixed gas through the infrared detection unit; obtain the absorbance of the counter-calibration sample based on the voltage signal value and the reference voltage value; Repeat the above steps at least 3 times to obtain the absorbance of at least 3 groups of reverse calibration samples; substitute the absorbance into the element content fitting formula to obtain the element content, and substitute the element content and the sample weight into the unit mass element content calculation formula to calculate the unit mass element content; compare the unit mass element content with the known standard value range of the element content to determine whether the calculated unit mass element content is within the known standard value range of the element content; If not, the element content fitting formula needs to be recalibrated and reconstructed.

5. The sample rapid combustion test method according to claim 1, characterized in that: It also includes the steps of constructing the ash value fitting formula: Weigh the residual mass of the reference sample after complete combustion, wherein the initial mass and the standard ash value of the reference sample are known, and calculate the mass ratio based on the residual mass and the initial mass; calculate the air-dry basis mass ratio of the reference sample according to the reference conversion formula; Repeat the above steps at least 10 times to obtain the air-to-dry basis mass ratios of at least 10 groups of reference samples; Get the ash value fitting formula , where: Y ad —Ash value, unit: %X ad —air-dry basis mass ratio, unit: %; Substitute the standard ash values ​​and air-dry basis mass ratios of at least 10 groups of reference samples into the ash value fitting formula to determine A, B, and C, and then determine the ash value fitting formula; Substituting the air-dry basis mass ratios of at least 10 groups of reference samples into the ash value fitting formula to calculate the ash value, performing difference calculation between the ash value and the standard ash value, and determining whether the differences are within a preset range; If not, the ash value fitting formula needs to be rebuilt.

6. A sample rapid combustion test device, characterized in that: It includes a combustion unit, a calorific value detection unit, an infrared detection unit, a weighing unit, a host computer system and an electronic control unit; The combustion unit comprises a combustion chamber and an oxygen filling part, and the combustion chamber and the oxygen filling part can be connected in an on-off manner; The calorific value detection unit is arranged inside the combustion unit, and is used to detect the temperature in the combustion chamber in real time when the sample is burning, and to provide a temperature rise curve of the sample during the combustion process from the beginning of combustion to the end of combustion until the temperature rise balance is reached; The infrared detection unit can be connected to the combustion unit in an on-off manner, and is used to detect the absorbance of the mixed gas generated by the sample after the combustion is completed, and analyze the element content in the sample; The weighing unit is located inside the combustion unit and is used to weigh the initial mass of the sample and the residual mass after complete combustion; The host computer system is used to analyze and calculate the data in the method described in any one of claims 1 to 5; The electronic control unit is communicatively connected with the combustion unit, the calorific value detection unit, the infrared detection unit, the weighing unit and the host computer system for running the method described in any one of claims 1-5.

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