CN109540828B - Infrared structural parameter method for coal quality analysis - Google Patents
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- RHZUVFJBSILHOK-UHFFFAOYSA-N anthracen-1-ylmethanolate Chemical compound C1=CC=C2C=C3C(C[O-])=CC=CC3=CC2=C1 RHZUVFJBSILHOK-UHFFFAOYSA-N 0.000 description 1
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Abstract
The invention relates to an infrared structural parameter method for coal quality analysis, which mainly solves the problems that the conventional coal quality analysis method at present cannot effectively characterize the macromolecular bonding structure of coal, so that the reactivity of the coal in the thermochemical conversion process cannot be effectively predicted and evaluated, and is a convenient, stable, reasonable, comprehensive and universal coal quality analysis method for characterizing the real macromolecular bonding structure of the coal; firstly, coal samples are 4000-400 cm‑1Dividing an original infrared spectrogram in a wave number range into six wave bands, then defining a base line of each wave band, carrying out curve fitting treatment on the original spectral line of each wave band, decomposing out a plurality of fitting sub-peaks, then calculating the area of each fitting sub-peak, determining the attribution of each fitting sub-peak, finally constructing and calculating a series of scientific, reasonable and clear-meaning infrared structure parameters, and carrying out comprehensive analysis and evaluation on the coal quality characteristics of each coal sample from the level of a molecular structure by comparing the relative height of the infrared structure parameter values of different coal samples.
Description
Technical Field
The invention belongs to the technical field of energy and environment, relates to supplement and innovation of a coal quality analysis method widely applied at present, and particularly relates to an infrared structural parameter method for coal quality analysis.
Background
The relationship between the structure and reactivity of coal is a core problem in the field of coal chemistry research, and is not only an important extension of relevant basic research of chemical science, but also a theoretical basis for development and progress of a plurality of coal processing and conversion technologies, such as gasification, coking and liquefaction technologies. The relationship between the structure and the reactivity of the coal is explored, and the fundamental premise is to realize effective characterization of the structure and the reactivity of the coal. However, due to the complexity of the coal components and the diversity of the coal types, there is no method for effectively resolving the real coal structure at the molecular level. For a long time, coal quality analysis technologies such as industrial analysis, elemental analysis, and lithofacies analysis constitute a conventional method system for characterizing coal structures in the fields of scientific research and industrial application. Although these coal quality analysis techniques and methods play an important role in the production process flow and reactor design using coal as a raw material, guidance of process systems and equipment operating parameters, and the like, they also have significant drawbacks and deficiencies.
The industrial analysis obtains the moisture, volatile components, fixed carbon and ash content of the whole coal under the test conditions, does not provide effective data about the chemical structure of the coal, strictly speaking, belongs to the test category of reactivity, and has very limited meaning for representing the coal structure. Elemental analysis provides C, H, O, N, S five-element content of the constituent coal, which seems to be a quantitative characterization of the coal chemical composition, however, the result is only a macroscopic average of the contents of several atoms of the heterogeneous coal, ignoring the chemical bond information that determines the bonding mode between the various atoms, and thus not effectively reflecting the macromolecular structure of the coal. Petrographic analysis, based on the differences in optical properties between the different components in coal, divides coal into several organic and mineral subgroups and gives the respective contents, which obviously does not give any clear chemical information. In summary, the coal quality analysis techniques and methods that are widely used today are based on certain external features, average properties, or macroscopic properties of coal, and lack characterization of the macromolecular bonding structure of coal.
The nature of any chemical reaction is the breaking and recombination of chemical bonds. Thus, the fundamental factor determining the reactivity of coal is the distribution characteristics of the chemical bonds between the various atoms that make up the coal. Therefore, effective characterization of the macromolecular bonding structure of coal is a fundamental prerequisite for predicting and evaluating the reactivity of coal in thermochemical conversion processes, and is also the final objective and ideal target of coal quality analysis. Particularly, for the thermal conversion technologies mainly based on pyrolysis reaction, such as direct coal liquefaction, indirect coal liquefaction, coking and the like, the distribution characteristics of macromolecular chemical bonds of the raw material coal can be effectively represented and evaluated, and the most direct scientific basis can be provided for the quality prediction of chemical products and byproducts.
Infrared spectroscopy, as a test analysis technique, has been used almost immediately for the characterization of coal chemical compositions since the last 40 th century as soon as it was developed. The infrared spectrum can give structural information of various functional groups in the coal, and the information is a direct description of the distribution characteristics of macromolecular chemical bonds of the coal. While this analytical technique has provided rich information about coal extraction, maturation, oxidation, liquefaction, and carbonization processes, it has long been a drawback of some methodologies that limit the rationality and breadth of its application in characterizing coal quality characteristics. Specifically, the following can be divided into:
1. lack of coal redThe full-band analysis of the outer spectrogram, therefore, the characterization of the coal quality characteristics is not sufficient and complete. At present, all analysis of coal macromolecule chemical structures by infrared spectroscopy in the world is only developed for a certain local waveband in an infrared spectrogram of coal, and the local waveband is not developed based on 4000-400 cm-1Analysis of the full-band range of infrared spectra of (1). Therefore, at present, all infrared spectroscopy analysis cannot realize complete characterization of coal quality characteristics.
2. The characterization method for the coal quality characteristics has defects. In some infrared spectroscopy analyses using KBr sheeting, the height or area of some absorption peaks is used directly to characterize the abundance of the corresponding functional group structure in coal. According to the Beer-Lambert principle, if each KBr pellet contains the same concentration of coal sample and has the same thickness, the intensity (i.e., height or area) of the absorption peak is proportional to the amount of functional group that causes absorption there. However, in the actual KBr pellet fabrication process, the preconditions for the Beer-Lambert principle application described above become nearly impossible to achieve due to errors in the weighing step, inadequate mixing in the grinding step, and imperfect flatness in the pellet step. Therefore, direct comparison of the absorption peak intensities of different coal samples is of very limited significance.
3. The method has insufficient universality and convenience. In some quantitative analysis of certain components of coal by infrared spectroscopy, workers have used standard substances. However, there is no clear guideline for the selection of suitable standard substances, and many times standard substances and spectra thereof are difficult to obtain. In addition, the infrared quantitative analysis process is also influenced by errors of each link of preparation of KBr tablets, and an additional chemical analysis means is also needed as an aid. The factors weaken the universality and convenience of the infrared analysis methods in the field of coal quality analysis.
4. The used infrared structural parameters are not rich enough and need to be supplemented urgently. The infrared structural parameters are constructed by utilizing the ratio of the area/height of certain specific absorption peaks in the infrared spectrogram of the coal, so that the infrared structural parameters are used for representing the coal quality characteristics, and the influence of errors of each link of KBr tablet preparation on an analysis result can be effectively avoided. While in some infrared spectroscopy, workers have used some infrared structural parameters (e.g., aliphatic hydrogen ratio, aromatic hydrogen ratio, aliphatic hydrogen/aromatic hydrogen ratio, aliphatic hydrogen + aromatic hydrogen ratio, etc.) to do this, these parameters are not sufficient to fully characterize the macromolecular structure of coal. For example, the aliphatic hydrogen and aromatic hydrogen ratios are descriptive of the partition ratio of hydrogen atoms in coal between aliphatic and aromatic structures, however, aliphatic chains of different lengths and degrees of branching, as well as aromatic ring systems of different degrees of condensation, have significantly different thermal stabilities and pyrolytic reactivities. Therefore, it is necessary to supplement parameters capable of effectively characterizing the internal characteristics of the fatty and aromatic structures for the comprehensive characterization of the coal quality.
5. Some infrared structural parameters are not reasonably constructed. In most of the work using structural parameters in the infrared for coal quality characterization, 1600cm in the infrared spectrum-1The most intense absorption peaks on the left and right are considered the most stable peaks, and their height/area is used as the denominator to construct the infrared structural parameters to characterize the relative content of certain functional groups. However, in some cases, the intensity of this absorption peak will be changed by the influence of the structure of other functional groups. For example, phenolic hydroxyl groups, methylene bridges, and ether linkages attached to aromatic ring structures increase the intensity of this peak, while an increase in the number of rings in a condensed aromatic system decreases the intensity of this peak. Therefore, the infrared structural parameters constructed by using the peak intensity as the denominator may be interfered by some errors and the characterization significance may be weakened.
In summary, no reasonable, effective, comprehensive and universal method for representing the real coal macromolecule bonding structure is formed in the world to date. The coal quality analysis method which can effectively and comprehensively characterize and describe the distribution characteristics of chemical bonds in real coal and has universality is developed, and has very important theoretical significance for the field of basic scientific research and very outstanding practical significance for the field of practical engineering application.
Disclosure of Invention
In order to solve the technical problems in the background art, the invention provides a coal quality analysis method which takes a Fourier transform infrared spectrometer as a testing instrument and can conveniently, reasonably, effectively, comprehensively and universally represent a real coal macromolecule bonding structure.
In order to achieve the aim, the invention provides an infrared structural parameter method for coal quality analysis, which has the technical key points that: the specific operation steps are as follows:
(1) preparing a coal sample meeting infrared spectrum testing conditions, adjusting a Fourier transform infrared spectrometer to meet testing parameters, and finally obtaining the coal sample of 4000-400 cm-1Raw IR spectra with high signal-to-noise ratio in the wavenumber range.
(2) Dividing the original infrared spectrogram into 3720-3581 cm by taking the lowest point of the corresponding trough of the original spectral line as a boundary point according to specific wave number ranges of different functional groups in different vibration modes-1、3099～2800cm-1、1874～1365cm-1、1334～950cm-1、950～671cm-1、622～439cm-1Six wave bands. According to the specific situation of different coal samples, the position of the dividing point is slightly deviated.
(3) And respectively selecting a series of base points on the original spectral lines of the various wave bands to define the base lines of the various wave bands. The base point is selected according to the following steps and principles: a. selecting demarcation points at two ends of a wave band; b. selecting the lowest point (if any) of characteristic wave troughs on the original spectral line of the wave band, and ensuring that similar selection is made at the similar position of the original spectral line for all coal samples; c. connecting each pair of adjacent base points by line segments, wherein all the line segments form a base line of the wave band; d. if the lowest valley point (namely the valley negative point) below the baseline appears on the original spectral line, selecting the lowest valley point as a base point, and then re-determining the baseline according to the step c; if a non-valley point (i.e., a common negative point) occurs on the original spectral line below the baseline, its value is zeroed.
(4) And (4) performing curve fitting processing on the original spectral lines of all wave bands according to the principle that each wave trough of the second derivative of the original spectral line corresponds to a hidden wave peak in the original spectral line. And separating the overlapped parts among the peaks by adopting a Voigt distribution function and a mode of fixing peak positions of the sub-peaks, and decomposing a plurality of fitting sub-peaks.
(5) The area of each fitted sub-peak is calculated and its attribution is determined.
(6) And constructing and calculating a series of infrared structure parameters representing the relative content of a certain type of functional group structure by taking the sum of the areas of all fitting sub-peaks of all wave bands as a reference, and constructing and calculating two infrared structure parameters representing the internal characteristics of the fatty component and the aromatic component respectively. The above infrared structural parameters include:
Ia1the ratio of the sum of the areas of the vibration peaks of the inorganic mineral to the sum of the areas of the peaks of all the fitter sub-peaks, i.e. AInorganic mineral/AGeneral assemblyCharacterizing the relative content of inorganic mineral substances in the coal;
Ia2the ratio of the sum of the areas of the vibrating peaks of the clay minerals to the sum of the areas of the peaks of all the fitter sub-peaks is AClay mineral/AGeneral assemblyCharacterizing the relative content of clay minerals in the coal;
Ib1the ratio of the sum of the areas of the fatty hydrogen oscillation peaks to the sum of the areas of all the fitted daughter peaks, namely AAliphatic hydrogen/AGeneral assemblyCharacterizing the relative content of fatty structures in the coal;
Ib2the ratio of the sum of the areas of the aromatic hydrogen oscillation peaks to the sum of the areas of all the fitted daughter peaks, i.e. AAromatic hydrogen/AGeneral assemblyCharacterizing the relative content of aromatic structures in the coal;
Ib3the ratio of the sum of the areas of the aliphatic hydrogen and aromatic hydrogen oscillation peaks to the sum of the areas of all fitted daughter peaks, i.e. Ib1+Ib2Characterizing the relative content of total hydrogen in the coal;
Ib4the ratio of the sum of the areas of the aliphatic hydrogen vibration peaks to the sum of the areas of the aromatic hydrogen vibration peaks, i.e. Ib1/Ib2The relative degree of the distribution proportion of hydrogen atoms in the coal between the aliphatic structure and the aromatic structure is represented;
Ic1the ratio of the sum of the C-O vibration peak areas of the carbon-oxygen single bond to the sum of the peak areas of all fitters, i.e. AC—O/AGeneral assemblyRepresenting the relative content of carbon-oxygen single bond structure in the coal;
Ic2the ratio of the sum of the areas of the C-O double bonds and the sum of the areas of all the fitter peaks, i.e. AC＝O/AGeneral assemblyRepresenting the relative content of the carbon-oxygen double bond structure in the coal;
Ic3-ratio of sum of areas of vibrating peaks of carboxylic acid groups COOH to sum of areas of peaks of all fitter groups, i.e. ACOOH/AGeneral assemblyCharacterizing the relative content of carboxylic acid groups in the coal;
Ic4the ratio of the sum of the areas of the vibration peaks of the C-O single bond and the C-O double bond to the sum of the areas of the peaks of all the fitter peaks, i.e. Ic1+Ic2Characterizing the relative content of total oxygen in the coal;
Ic5the ratio of the sum of C-O vibration peak areas of the C-O single bonds to the sum of C-O vibration peak areas of the C-O double bonds, i.e. Ic1/Ic2The relative proportion of oxygen atoms in the coal between carbon-oxygen single bond C-O and carbon-oxygen double bond C ═ O structures is represented;
Id1-CH in the fatty Structure2Peak area of vibration and CH3Ratio of vibration peak area, i.e. ACH2/ACH3Characterizing the length or branching degree of the fatty side chain and the bridge bond in the coal, wherein the larger the parameter value is, the longer the fatty side chain and the bridge bond are, or the lower the branching degree is;
Id2the ratio of the sum of the vibration peak areas of the isolated or two adjacent hydrogen in the aromatic structure to the telescopic vibration peak area of the aromatic hydrogen is A1H+2H/AExpansion of aromatic hydrogenThe relative proportion of rings that characterize the degree of high substitution or condensation in an aromatic ring system.
(7) And comparing the relative height of the infrared structural parameter values of different coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of each coal sample according to the characterization significance of each parameter.
Compared with the prior art, the invention has the following beneficial effects:
1. the method can realize effective characterization of a real coal macromolecular bonding structure which cannot be realized by the conventional coal quality analysis method, thereby providing a direct basis for predicting and evaluating the reactivity of the coal in the thermochemical conversion process. In particular, for the thermal conversion technologies mainly based on the pyrolysis reaction, such as direct coal liquefaction, indirect coal liquefaction, coking and the like, the most direct scientific basis can be provided for the quality prediction of chemical products and byproducts.
2. Can realize 4000-400 cm of coal infrared spectrogram-1And (3) performing full-band analysis of the range, thereby realizing full and complete characterization of the coal quality characteristics.
3. The infrared structural parameters are constructed according to the specific ratio of specific absorption peak areas in the infrared spectrogram of the coal sample, so that the infrared structural parameters are used for representing the coal quality characteristics, and the influence of errors in each link of KBr tablet preparation of the coal sample on an analysis result can be effectively avoided.
4. Standard substances and additional chemical analysis means are not needed, so that the universality and the convenience of the application of the coal quality analysis method are ensured.
5. The sum of the areas of all absorption peaks in the coal infrared spectrogram is used as a reference to construct the infrared structure parameter, so that the condition that a single peak (such as 1600 cm) is used as an effective avoidance mode-1Off-peak) area as a reference, interference and errors may be introduced due to poor stability of individual peaks when constructing infrared structural parameters.
6. And abundant infrared structural parameters are introduced, so that comprehensive characterization of coal quality characteristics can be realized.
7. For the infrared spectrogram of the same coal sample, the repeatability of the obtained infrared structural parameter calculation result is excellent, and the stability and the scientificity of the coal quality analysis method are ensured.
8. For infrared spectrograms of different coal samples, the obtained fitting sub-peak representing the same functional groups and the same vibration forms has small peak position deviation, and the reasonability and universality of the coal quality analysis method are ensured.
Drawings
FIG. 1 is a raw IR spectrum of a first embodiment of the present invention;
FIG. 2 is a result of peak-splitting fitting for each band according to the first embodiment of the present invention;
FIG. 3 is a raw IR spectrum of example two of the present invention;
FIG. 4 is a result of peak-splitting fitting for each band according to the second embodiment of the present invention;
FIG. 5 is a raw IR spectrum of example III of the present invention;
FIG. 6 is a result of peak-splitting fitting for each band according to the third embodiment of the present invention;
FIG. 7 is a raw IR spectrum of example four of the present invention;
FIG. 8 is a result of peak-splitting fitting for each band according to the fourth embodiment of the present invention;
FIG. 9 is a raw IR spectrum of example V of the present invention;
FIG. 10 shows the peak-splitting fitting results of the bands according to the fifth embodiment of the present invention;
FIG. 11 is a raw IR spectrum of example six of the present invention;
FIG. 12 shows the peak-to-peak fitting results of the various bands according to the sixth embodiment of the present invention;
FIG. 13 is a raw IR spectrum of example VII of the present invention;
FIG. 14 shows the peak-splitting fitting results of each band according to the seventh embodiment of the present invention;
FIG. 15 shows examples I of the first to seventh embodiments of the present inventiona1Value and dry base ash value A in Industrial analysisdThe correlation between them;
FIG. 16 shows examples I of the first to seventh embodiments of the present inventionb3Value and dry-based hydrogen content H in elemental analysisdThe correlation between them;
FIG. 17 shows examples I of the first to seventh embodiments of the present inventionc4Value and dry oxygen content in elemental analysis OdThe correlation between them.
The above embodiments represent the application of the infrared structural parameter method for coal quality analysis to different coal types, which is a process of analyzing infrared structural parameters of 7 coal samples with coal rank from low to high, in the present invention, and the specific data processing and analyzing steps will be described in detail below.
Detailed Description
The invention is further described with reference to the following figures and specific examples.
As shown in fig. 1 to 17, the invention provides an infrared structural parameter method for coal quality analysis, which comprises the following specific operation steps:
(1) and preparing a coal sample meeting infrared spectrum testing conditions by adopting a proper sample preparation method, and adjusting the Fourier transform infrared spectrometer to proper testing parameters to finally obtain the original infrared spectrogram of the coal sample with high signal-to-noise ratio.
(2) And dividing the original infrared spectrogram into six wave bands by taking the lowest point of the corresponding wave trough of the original spectral line as a demarcation point according to the specific wave number ranges of different functional groups in different vibration modes.
(3) And respectively selecting a series of base points on the original spectral lines of the various wave bands to define the base lines of the various wave bands.
(4) And (3) according to the principle that each trough of the second derivative of the original spectral line corresponds to a hidden peak in the original spectral line, performing curve fitting treatment on the original spectral line of each wave band, separating the overlapped part between the peaks, and decomposing into a plurality of fitting sub-peaks.
(5) The area of each fitted sub-peak is calculated and its attribution is determined.
(6) Establishing and calculating a series of infrared structure parameters representing the relative content of a certain type of functional group structure by taking the sum of the areas of all fitting sub-peaks of all wave bands as a reference; and simultaneously constructing and calculating two infrared structure parameters respectively representing the internal characteristics of the fatty component and the aromatic component.
(7) And comparing the relative height of the infrared structural parameter values of different coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of each coal sample according to the characterization significance of each parameter.
The wave number range of the original infrared spectrogram of the coal sample is 4000-400 cm-1。
The six wave bands are 3720-3581 cm respectively-1、3099～2800cm-1、1874～1365cm-1、1334～950cm-1、950～671cm-1、622～439cm-1(ii) a According to the specific situation of different coal samples, the positions of the wave band dividing points are slightly deviated.
The base point is selected according to the following steps and principles: a. selecting demarcation points at two ends of a wave band; b. the lowest point of the characteristic trough, if any, on the original spectral line of the band is chosen and it is ensured that for all coal samples a similar choice is made in the close position of the original spectral line.
The baseline is determined according to the following steps and principles: a. connecting each pair of adjacent base points by line segments, wherein all the line segments form a base line of the wave band; b. if the lowest valley point (namely the valley negative point) below the baseline appears on the original spectral line, selecting the lowest valley point as a base point, and then re-determining the baseline according to the step a; if a non-valley point (i.e., a common negative point) occurs on the original spectral line below the baseline, its value is zeroed.
The curve fitting treatment is carried out by adopting a Voigt distribution function and a fixer peak position mode.
The infrared structural parameters comprise:
Ia1-the ratio of the sum of the areas of the inorganic mineral vibratory peaks to the sum of the areas of all of said fitted sub-peaks, namely AInorganic mineral/AGeneral assemblyCharacterizing the relative content of inorganic mineral substances in the coal;
Ia2-the ratio of the sum of the areas of the vibrating peaks of the clay minerals to the sum of the areas of the peaks of all said fitter peaks, i.e. AClay mineral/AGeneral assemblyCharacterizing the relative content of clay minerals in the coal;
Ib1-the ratio of the sum of the areas of the fatty hydrogen oscillation peaks to the sum of the areas of all of the fitted daughter peaks, namely AAliphatic hydrogen/AGeneral assemblyCharacterizing the relative content of fatty structures in the coal;
Ib2-the ratio of the sum of the areas of the aromatic hydrogen oscillation peaks to the sum of the areas of all of said fitted daughter peaks, namely AAromatic hydrogen/AGeneral assemblyCharacterizing the relative content of aromatic structures in the coal;
Ib3the ratio of the sum of the areas of the aliphatic hydrogen and aromatic hydrogen oscillation peaks to the sum of the areas of all of the fitted daughter peaks, i.e. Ib1+Ib2Characterizing the relative content of total hydrogen in the coal;
Ib4the ratio of the sum of the areas of the aliphatic hydrogen vibration peaks to the sum of the areas of the aromatic hydrogen vibration peaks, i.e. Ib1/Ib2The relative degree of the distribution proportion of hydrogen atoms in the coal between the aliphatic structure and the aromatic structure is represented;
Ic1the ratio of the sum of the C-O vibration peak areas of the carbon-oxygen single bond to the sum of the peak areas of all the fitter peaks, i.e. AC—O/AGeneral assemblyRepresenting the relative content of carbon-oxygen single bond structure in the coal;
Ic2the ratio of the sum of the areas of the C-O double bond peaks to the sum of the areas of all the fitter peaks, i.e. AC＝O/AGeneral assemblyRepresenting the relative content of the carbon-oxygen double bond structure in the coal;
Ic3-ratio of sum of areas of vibrating peaks of carboxylic acid groups COOH to sum of areas of peaks of all said fitter groups, namely ACOOH/AGeneral assemblyCharacterizing the relative content of carboxylic acid groups in the coal;
Ic4the ratio of the sum of the areas of the peaks of the C-O single bond and C-O double bond to the sum of the areas of all the peak regions of said fitter, i.e. Ic1+Ic2Characterizing the relative content of total oxygen in the coal;
Ic5the ratio of the sum of C-O vibration peak areas of the C-O single bonds to the sum of C-O vibration peak areas of the C-O double bonds, i.e. Ic1/Ic2The relative proportion of oxygen atoms in the coal between carbon-oxygen single bond C-O and carbon-oxygen double bond C ═ O structures is represented;
Id1-CH in the fatty Structure2Peak area of vibration and CH3Ratio of vibration peak area, i.e. ACH2/ACH3Characterizing the length or branching degree of the fatty side chain and the bridge bond in the coal, wherein the larger the parameter value is, the longer the fatty side chain and the bridge bond are, or the lower the branching degree is;
Id2the ratio of the sum of the vibration peak areas of the isolated or two adjacent hydrogen in the aromatic structure to the telescopic vibration peak area of the aromatic hydrogen is A1H+2H/AExpansion of aromatic hydrogenCharacterised by the degree of high substitution or condensation in the aromatic ring systemRelative proportion of rings.
Example 1
The dry-based industrial and elemental analysis data for a sample of lignite is shown in table 1.
Table 1 example 1 dry-based industrial and elemental analysis data for coal samples
aCalculated by difference subtraction
According to the specific operation steps (1) to (7) in the invention, the infrared structural parameter analysis of the coal sample is completed according to the following method by combining the specific situation of the coal sample:
(1) the infrared spectrum test coal sample is prepared by a KBr tablet pressing method. The sample and KBr are firstly fully mixed in a mass ratio of 1:200, then 200mg of the mixture is made into an infrared tablet under the pressure of 10-12 MPa, and finally the tablet is dried in a thermostat at 50 ℃ for at least 48 hours to prepare for testing. The test wave number range of the Fourier transform infrared spectrometer is 4000-400 cm-1Resolution of 4cm-1The number of scans was 32. The final obtained original infrared spectrum of the coal sample is shown in fig. 1.
(2) Dividing an original infrared spectrogram into 3716-3586 cm-1、3099～2809cm-1、1874～1365cm-1、1334～952cm-1、950～673cm-1、617～439cm-1Six wave bands.
(3) A series of base points are selected on the original spectral lines of the respective bands to define a baseline of the respective bands. The baseline definition results were as follows:
a.3716～3586cm-1wave band: 3716-3681-3663-3586;
b.3099～2809cm-1wave band: 3099-2995-2809;
c.1874～1365cm-1wave band:
1874—1805—1787—1777—1764—1744—1669—1483—1387—1365；
d.1334～952cm-1wave band: 1334-952;
e.950～673cm-1wave band: 950-892-849-716-673;
f.617～439cm-1wave band: 617-439.
(4) And carrying out curve fitting treatment on the original spectral lines of all wave bands to decompose a plurality of fitting sub-peaks, wherein the result of peak-splitting fitting is shown in figure 2.
(5) The area of each fitted sub-peak was calculated and assigned, and the results are shown in table 2.
(6) The following infrared structural parameters were constructed and calculated:
Ia1＝Ainorganic mineral/AGeneral assembly
＝(A1+A2+A3+A12+A13+A14+A15+A16+A17+A18+A19+A20+A55+
A56+A57+A58+A59+A60+A61+A62+A63+A64+A65+A66+A67+
A68)/A1～68；
Ia2＝AClay mineral/AGeneral assembly
＝(A3+A12+A13+A14+A15+A16+A17+A20+A55+A56+A57+A58+A59+
A60+A61+A62+A63+A64+A65+A66+A67+A68)/A1～68；
Ib1＝AAliphatic hydrogen/AGeneral assembly＝(A49+A50+A51+A52+A53)/A1～68；
Ib2＝AAromatic hydrogen/AGeneral assembly＝(A9+A10+A11+A54)/A1～68；
Ib3＝Ib1+Ib2；
Ib4＝Ib1/Ib2；
Ic1＝AC—O/AGeneral assembly＝(A23+A24+A25+A26)/A1～68；
Ic2＝AC＝O/AGeneral assembly
＝(A37+A38+A39+A40+A41+A42+A43+A44+A45+A46+A47+
A48)/A1～68；
Ic3＝ACOOH/AGeneral assembly＝A39/A1～68；
Ic4＝Ic1+Ic2；
Ic5＝Ic1/Ic2；
Id1＝ACH2/ACH3＝A52/A53；
Id2＝A1H+2H/AExpansion of aromatic hydrogen＝(A9+A10+A11)/A54。
The results of the calculation of the respective infrared structural parameters are shown in table 3.
(7) And comparing the relative height of the infrared structural parameter values of the coal sample with that of other coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of the coal sample according to the characterization significance of each parameter.
Table 2 area and assignment of each of the fitted sub-peaks of example 1
Table 3 calculated values of various infrared structural parameters of example 1
Example 2
The dry-based industrial and elemental analysis data for a sample of bituminous coal is shown in table 4.
Table 4 example 2 dry-based industrial and elemental analysis data for coal samples
aCalculated by difference subtraction
According to the specific operation steps (1) to (7) in the invention, the infrared structural parameter analysis of the coal sample is completed according to the following method by combining the specific situation of the coal sample:
(1) the infrared spectrum test coal sample is prepared by a KBr tablet pressing method. The sample and KBr are firstly fully mixed in a mass ratio of 1:200, then 200mg of the mixture is made into an infrared tablet under the pressure of 10-12 MPa, and finally the tablet is dried in a thermostat at 50 ℃ for at least 48 hours to prepare for testing. The test wave number range of the Fourier transform infrared spectrometer is 4000-400 cm-1Resolution of 4cm-1The number of scans was 32. The final original infrared spectrum of the obtained coal sample is shown in fig. 3.
(2) Dividing an original infrared spectrogram into 3716-3586 cm-1、3099～2809cm-1、1874～1365cm-1、1334～950cm-1、950～682cm-1、622～453cm-1Six wave bands.
(3) A series of base points are selected on the original spectral lines of the respective bands to define a baseline of the respective bands. The baseline definition results were as follows:
a.3716～3586cm-1wave band: 3716-3681-3663-3586;
b.3099～2809cm-1wave band: 3099-2991-2809;
c.1874～1365cm-1wave band:
1874—1805—1787—1777—1669—1483—1387—1365；
d.1334～950cm-1wave band: 1334-950;
e.950～682cm-1wave band: 950-932-682;
f.622～453cm-1wave band: 622-453.
(4) The curve fitting treatment is carried out on the original spectral lines of all wave bands, a plurality of fitting sub-peaks are decomposed, and the peak-splitting fitting result is shown in figure 4.
(5) The area of each fitted sub-peak was calculated and assigned, and the results are shown in table 5.
(6) The following infrared structural parameters were constructed and calculated:
Ia1＝Ainorganic mineral/AGeneral assembly
＝(A1+A2+A12+A13+A14+A15+A16+A17+A18+A19+A54+A55+A56+
A57+A58+A59+A60+A61+A62+A63+A64+A65+A66+A67)/A1～67；
Ia2＝AClay mineral/AGeneral assembly
＝(A2+A12+A13+A14+A15+A16+A19+A54+A55+A56+A57+A58+A59+
A60+A61+A62+A63+A64+A65+A66+A67)/A1～67；
Ib1＝AAliphatic hydrogen/AGeneral assembly＝(A48+A49+A50+A51+A52)/A1～67；
Ib2＝AAromatic hydrogen/AGeneral assembly＝(A9+A10+A11+A53)/A1～67；
Ib3＝Ib1+Ib2；
Ib4＝Ib1/Ib2；
Ic1＝AC—O/AGeneral assembly＝(A22+A23+A24+A25)/A1～67；
Ic2＝AC＝O/AGeneral assembly
＝(A36+A37+A38+A39+A40+A41+A42+A43+A44+A45+A46+
A47)/A1～67；
Ic3＝ACOOH/AGeneral assembly＝A38/A1～67；
Ic4＝Ic1+Ic2；
Ic5＝Ic1/Ic2；
Id1＝ACH2/ACH3＝A51/A52；
Id2＝A1H+2H/AExpansion of aromatic hydrogen＝(A9+A10+A11)/A53。
The results of the calculation of the respective infrared structural parameters are shown in table 6.
(7) And comparing the relative height of the infrared structural parameter values of the coal sample with that of other coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of the coal sample according to the characterization significance of each parameter.
TABLE 5 area and assignment of each of the fitted sub-peaks of example 2
Table 6 calculated values of various infrared structural parameters of example 2
Example 3
Dry-based industrial and elemental analysis data for a sample of a low-order bituminous coal are shown in table 7.
Table 7 example 3 dry-based industrial and elemental analysis data for coal samples
aCalculated by difference subtraction
According to the specific operation steps (1) to (7) in the invention, the infrared structural parameter analysis of the coal sample is completed according to the following method by combining the specific situation of the coal sample:
(1) the infrared spectrum test coal sample is prepared by a KBr tablet pressing method. The sample and KBr are firstly fully mixed in a mass ratio of 1:200, then 200mg of the mixture is made into an infrared tablet under the pressure of 10-12 MPa, and finally the tablet is dried in a thermostat at 50 ℃ for at least 48 hours to prepare for testing. The test wave number range of the Fourier transform infrared spectrometer is 4000-400 cm-1Resolution of 4cm-1The number of scans was 32. The final original infrared spectrum of the obtained coal sample is shown in fig. 5.
(2) Dividing an original infrared spectrogram into 3716-3586 cm-1、3099～2809cm-1、1874～1365cm-1、1334～950cm-1、950～671cm-1、619～441cm-1Six wave bands.
(3) A series of base points are selected on the original spectral lines of the respective bands to define a baseline of the respective bands. The baseline definition results were as follows:
a.3716～3586cm-1wave band: 3716-3681-3663-3586;
b.3099～2809cm-1wave band: 3099-2993-2809;
c.1874～1365cm-1wave band:
1874—1805—1787—1777—1764—1744—1669—1483—1387—1365；
d.1334～950cm-1wave band: 1334-950;
e.950～671cm-1wave band: 950-930-671;
f.619～441cm-1wave band: 619-441.
(4) The curve fitting treatment is carried out on the original spectral lines of all wave bands, a plurality of fitting sub-peaks are decomposed, and the peak-splitting fitting result is shown in figure 6.
(5) The area of each fitted sub-peak was calculated and assigned, and the results are shown in table 8.
(6) The following infrared structural parameters were constructed and calculated:
Ia1＝Ainorganic mineral/AGeneral assembly
＝(A1+A2+A12+A13+A14+A15+A16+A17+A18+A19+A54+A55+A56+
A57+A58+A59+A60+A61+A62+A63+A64+A65+A66+A67)/A1～67；
Ia2＝AClay mineral/AGeneral assembly
＝(A2+A12+A13+A14+A15+A16+A19+A54+A55+A56+A57+A58+A59+
A60+A61+A62+A63+A64+A65+A66+A67)/A1～67；
Ib1＝AAliphatic hydrogen/AGeneral assembly＝(A48+A49+A50+A51+A52)/A1～67；
Ib2＝AAromatic hydrogen/AGeneral assembly＝(A8+A9+A10+A11+A53)/A1～67；
Ib3＝Ib1+Ib2；
Ib4＝Ib1/Ib2；
Ic1＝AC—O/AGeneral assembly＝(A22+A23+A24+A25)/A1～67；
Ic2＝AC＝O/AGeneral assembly
＝(A36+A37+A38+A39+A40+A41+A42+A43+A44+A45+A46+
A47)/A1～67；
Ic3＝ACOOH/AGeneral assembly＝A38/A1～67；
Ic4＝Ic1+Ic2；
Ic5＝Ic1/Ic2；
Id1＝ACH2/ACH3＝A51/A52；
Id2＝A1H+2H/AExpansion of aromatic hydrogen＝(A8+A9+A10+A11)/A53。
The results of the calculation of the respective infrared structural parameters are shown in table 9.
(7) And comparing the relative height of the infrared structural parameter values of the coal sample with that of other coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of the coal sample according to the characterization significance of each parameter.
TABLE 8 EXAMPLE 3 area and assignment of each of the fitted sub-peaks
TABLE 9 calculated values of various infrared structural parameters of example 3
Example 4
Dry-based industrial and elemental analysis data for a sample of bituminous coal are shown in table 10.
Table 10 example 4 dry-based industrial and elemental analysis data for coal samples
aCalculated by difference subtraction
According to the specific operation steps (1) to (7) in the invention, the infrared structural parameter analysis of the coal sample is completed according to the following method by combining the specific situation of the coal sample:
(1) the infrared spectrum test coal sample is prepared by a KBr tablet pressing method. The sample and KBr were first mixed well in a mass ratio of 1:200And then making 200mg of the mixture into an infrared tablet under the pressure of 10-12 MPa, and finally drying the tablet in a thermostat at 50 ℃ for at least 48 hours for testing. The test wave number range of the Fourier transform infrared spectrometer is 4000-400 cm-1Resolution of 4cm-1The number of scans was 32. The final obtained original infrared spectrum of the coal sample is shown in fig. 7.
(2) Dividing an original infrared spectrogram into 3716-3586 cm-1、3099～2800cm-1、1874～1365cm-1、1334～950cm-1、950～671cm-1、595～439cm-1Six wave bands.
(3) A series of base points are selected on the original spectral lines of the respective bands to define a baseline of the respective bands. The baseline definition results were as follows:
a.3716～3586cm-1wave band: 3716-3663-3629-3586;
b.3099～2800cm-1wave band: 3099-2991-2800;
c.1874～1365cm-1wave band:
1874—1833—1814—1787—1777—1764—1754—1744—1669—1529—1365；
d.1334～950cm-1wave band: 1334-950;
e.950～671cm-1wave band: 950-930-903-671;
f.595～439cm-1wave band: 595 to 439.
(4) The curve fitting treatment is carried out on the original spectral lines of all wave bands, a plurality of fitting sub-peaks are decomposed, and the peak-splitting fitting result is shown in figure 8.
(5) The area of each fitted sub-peak was calculated and assigned, and the results are shown in table 11.
(6) The following infrared structural parameters were constructed and calculated:
Ia1＝Ainorganic mineral/AGeneral assembly
＝(A1+A2+A3+A15+A16+A17+A18+A19+A20+A21+A22+A57+A58
+A59+A60+A61+A62+A63+A64+A65+A66+A67+A68+A69+
A70)/A1～70；
Ia2＝AClay mineral/AGeneral assembly
＝(A3+A15+A16+A17+A18+A19+A22+A57+A58+A59+A60+A61+
A62+A63+A64+A65+A66+A67+A68+A69+A70)/A1～70；
Ib1＝AAliphatic hydrogen/AGeneral assembly＝(A51+A52+A53+A54+A55)/A1～70；
Ib2＝AAromatic hydrogen/AGeneral assembly＝(A11+A12+A13+A14+A56)/A1～70；
Ib3＝Ib1+Ib2；
Ib4＝Ib1/Ib2；
Ic1＝AC—O/AGeneral assembly＝(A25+A26+A27+A28)/A1～70；
Ic2＝AC＝O/AGeneral assembly
＝(A39+A40+A41+A42+A43+A44+A45+A46+A47+A48+A49+
A50)/A1～70；
Ic3＝ACOOH/AGeneral assembly＝A41/A1～70；
Ic4＝Ic1+Ic2；
Ic5＝Ic1/Ic2；
Id1＝ACH2/ACH3＝A54/A55；
Id2＝A1H+2H/AExpansion of aromatic hydrogen＝(A11+A12+A13+A14)/A56。
The results of the calculation of the respective infrared structural parameters are shown in table 12.
(7) And comparing the relative height of the infrared structural parameter values of the coal sample with that of other coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of the coal sample according to the characterization significance of each parameter.
TABLE 11 area and assignment of each of the fitted sub-peaks of example 4
TABLE 12 calculated values of various infrared structural parameters of example 4
Example 5
Dry-based industrial and elemental analysis data for a sample of bituminous coal are shown in table 13.
Table 13 example 5 dry-based industrial and elemental analysis data for coal samples
aCalculated by difference subtraction
According to the specific operation steps (1) to (7) in the invention, the infrared structural parameter analysis of the coal sample is completed according to the following method by combining the specific situation of the coal sample:
(1) the infrared spectrum test coal sample is prepared by a KBr tablet pressing method. The sample and KBr are firstly fully mixed in a mass ratio of 1:200, then 200mg of the mixture is made into an infrared tablet under the pressure of 10-12 MPa, and finally the tablet is dried in a thermostat at 50 ℃ for at least 48 hours to prepare for testing. The test wave number range of the Fourier transform infrared spectrometer is 4000-400 cm-1Resolution of 4cm-1The number of scans was 32. The final original infrared spectrum of the obtained coal sample is shown in fig. 9.
(2) Dividing an original infrared spectrogram into 3716-3586 cm-1、3099～2800cm-1、1874～1365cm-1、1334～950cm-1、950～671cm-1、619～441cm-1Six wave bands.
(3) A series of base points are selected on the original spectral lines of the respective bands to define a baseline of the respective bands. The baseline definition results were as follows:
a.3716～3586cm-1wave band: 3716-3682-3663-3586;
b.3099～2800cm-1wave band: 3099-2991-2800;
c.1874～1365cm-1wave band:
1874—1805—1787—1777—1764—1744—1669—1365；
d.1334～950cm-1wave band: 1334-950;
e.950～671cm-1wave band: 950-928-671;
f.619～441cm-1wave band: 619-441.
(4) Curve fitting processing is carried out on the original spectral lines of all wave bands, a plurality of fitting sub-peaks are decomposed, and the result of peak-splitting fitting is shown in figure 10.
(5) The area of each fitted sub-peak was calculated and assigned, and the results are shown in table 14.
(6) The following infrared structural parameters were constructed and calculated:
Ia1＝Ainorganic mineral/AGeneral assembly
＝(A1+A2+A3+A14+A15+A16+A17+A18+A19+A20+A55+A56+A57+
A58+A59+A60+A61+A62+A63+A64+A65+A66+A67+A68+
A69)/A1～69；
Ia2＝AClay mineral/AGeneral assembly
＝(A3+A14+A15+A16+A17+A18+A55+A56+A57+A58+A59+A60+
A61+A62+A63+A64+A65+A66+A67+A68+A69)/A1～69；
Ib1＝AAliphatic hydrogen/AGeneral assembly＝(A49+A50+A51+A52+A53)/A1～69；
Ib2＝AAromatic hydrogen/AGeneral assembly＝(A10+A11+A12+A13+A54)/A1～69；
Ib3＝Ib1+Ib2；
Ib4＝Ib1/Ib2；
Ic1＝AC—O/AGeneral assembly＝(A23+A24+A25+A26)/A1～69；
Ic2＝AC＝O/AGeneral assembly
＝(A37+A38+A39+A40+A41+A42+A43+A44+A45+A46+A47+
A48)/A1～69；
Ic3＝ACOOH/AGeneral assembly＝A39/A1～69；
Ic4＝Ic1+Ic2；
Ic5＝Ic1/Ic2；
Id1＝ACH2/ACH3＝A52/A53；
Id2＝A1H+2H/AExpansion of aromatic hydrogen＝(A10+A11+A12+A13)/A54。
The results of the calculation of the respective infrared structural parameters are shown in table 15.
(7) And comparing the relative height of the infrared structural parameter values of the coal sample with that of other coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of the coal sample according to the characterization significance of each parameter.
TABLE 14 area and assignment of each of the fitted sub-peaks of example 5
TABLE 15 calculated values of various infrared structural parameters of example 5
Example 6
Dry-based industrial and elemental analysis data for a sample of a high rank bituminous coal are shown in table 16.
Table 16 example 6 dry-based industrial and elemental analysis data for coal samples
aCalculated by difference subtraction
According to the specific operation steps (1) to (7) in the invention, the infrared structural parameter analysis of the coal sample is completed according to the following method by combining the specific situation of the coal sample:
(1) the infrared spectrum test coal sample is prepared by a KBr tablet pressing method. The sample and KBr are firstly fully mixed in a mass ratio of 1:250, then 200mg of the mixture is made into an infrared tablet under the pressure of 10-12 MPa, and finally the tablet is dried in a thermostat at 50 ℃ for at least 48 hours to prepare for testing. The test wave number range of the Fourier transform infrared spectrometer is 4000-400 cm-1Resolution of 4cm-1The number of scans was 32. The final original infrared spectrum of the obtained coal sample is shown in fig. 11.
(2) Dividing an original infrared spectrogram into 3716-3586 cm-1、3099～2800cm-1、1874～1365cm-1、1334～950cm-1、950～671cm-1、619～441cm-1Six wave bands.
(3) A series of base points are selected on the original spectral lines of the respective bands to define a baseline of the respective bands. The baseline definition results were as follows:
a.3716～3586cm-1wave band: 3716-3586;
b.3099～2800cm-1wave band: 3099-2988-2800;
c.1874～1365cm-1wave band:
1874—1805—1787—1777—1764—1755—1744—1726—1690—1681—1669—1514—1502—1492—1483—1389—1365；
d.1334～950cm-1wave band: 1334-950;
e.950～671cm-1wave band: 950-712-671;
f.619～441cm-1wave band: 619-441.
(4) Curve fitting processing is carried out on the original spectral lines of all wave bands, a plurality of fitting sub-peaks are decomposed, and the peak-splitting fitting result is shown in figure 12.
(5) The area of each fitted sub-peak was calculated and assigned, and the results are shown in table 17.
(6) The following infrared structural parameters were constructed and calculated:
Ia1＝Ainorganic mineral/AGeneral assembly
＝(A1+A2+A3+A13+A14+A15+A16+A17+A18+A19+A20+A27+A57+
A58+A59+A60+A61+A62+A63+A64+A65+A66+A67+A68+A69+
A70)/A1～70；
Ia2＝AClay mineral/AGeneral assembly
＝(A3+A13+A14+A15+A16+A17+A20+A57+A58+A59+A60+A61+
A62+A63+A64+A65+A66+A67+A68+A69+A70)/A1～70；
Ib1＝AAliphatic hydrogen/AGeneral assembly＝(A51+A52+A53+A54+A55)/A1～70；
Ib2＝AAromatic hydrogen/AGeneral assembly＝(A9+A10+A11+A12+A56)/A1～70；
Ib3＝Ib1+Ib2；
Ib4＝Ib1/Ib2；
Ic1＝AC—O/AGeneral assembly＝(A23+A24+A25)/A1～70；
Ic2＝AC＝O/AGeneral assembly
＝(A37+A38+A39+A40+A41+A42+A43+A44+A45+A46+A47+A48+
A49+A50)/A1～70；
Ic3＝ACOOH/AGeneral assembly＝(A39+A40+A41)/A1～70；
Ic4＝Ic1+Ic2；
Ic5＝Ic1/Ic2；
Id1＝ACH2/ACH3＝A54/A55；
Id2＝A1H+2H/AExpansion of aromatic hydrogen＝(A9+A10+A11+A12)/A56。
The results of the calculation of the respective infrared structural parameters are shown in table 18.
(7) And comparing the relative height of the infrared structural parameter values of the coal sample with that of other coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of the coal sample according to the characterization significance of each parameter.
TABLE 17 area and assignment of each of the fitted sub-peaks of example 6
TABLE 18 calculated values of various infrared structural parameters of example 6
Example 7
The dry-based industrial and elemental analysis data for a sample of anthracite coal is shown in Table 19.
Table 19 example 7 dry-based industrial and elemental analysis data for coal samples
aCalculated by difference subtraction
According to the specific operation steps (1) to (7) in the invention, the infrared structural parameter analysis of the coal sample is completed according to the following method by combining the specific situation of the coal sample:
(1) the infrared spectrum test coal sample is prepared by a KBr tablet pressing method. Fully mixing a sample and KBr in a mass ratio of 1:300, preparing 200mg of mixture into an infrared tablet under the pressure of 10-12 MPa, and finally drying the tablet in a thermostat at 50 ℃ to at least48 hours before testing. The test wave number range of the Fourier transform infrared spectrometer is 4000-400 cm-1Resolution of 4cm-1The number of scans was 32. The final original infrared spectrum of the obtained coal sample is shown in fig. 13.
(2) Dividing an original infrared spectrogram into 3720-3581 cm-1、3097～2807cm-1、1658～1365cm-1、1334～958cm-1、958～671cm-1、622～445cm-1Six wave bands.
(3) A series of base points are selected on the original spectral lines of the respective bands to define a baseline of the respective bands. The baseline definition results were as follows:
a.3720～3581cm-1wave band: 3720-3581;
b.3097～2807cm-1wave band: 3097-3088-2988-2926-2807;
c.1658～1365cm-1wave band: 1658-1630-1483-1365;
d.1334～958cm-1wave band: 1334-958;
e.958～671cm-1wave band: 958-888-844-722-671;
f.622～445cm-1wave band: 622-445.
(4) Curve fitting processing is carried out on the original spectral lines of all wave bands, a plurality of fitting sub-peaks are decomposed, and the result of peak-splitting fitting is shown in figure 14.
(5) The area of each fitted sub-peak was calculated and assigned, and the results are shown in table 20.
(6) The following infrared structural parameters were constructed and calculated:
Ia1＝Ainorganic mineral/AGeneral assembly
＝(A1+A2+A11+A12+A13+A14+A15+A16+A17+A18+A39+A40+A41+
A42+A43+A44+A45+A46+A47+A48+A49)/A1～49；
Ia2＝AClay mineral/AGeneral assembly
＝(A2+A11+A12+A13+A14+A15+A18+A39+A40+A41+A42+A43+A44+
A45+A46+A47+A48+A49)/A1～49；
Ib1＝AAliphatic hydrogen/AGeneral assembly＝(A33+A34+A35+A36+A37)/A1～49；
Ib2＝AAromatic hydrogen/AGeneral assembly＝(A8+A9+A10+A38)/A1～49；
Ib3＝Ib1+Ib2；
Ib4＝Ib1/Ib2；
Ic1＝AC—O/AGeneral assembly＝0；
Ic2＝AC＝O/AGeneral assembly
＝(A30+A31+A32)/A1～49；
Ic3＝ACOOH/AGeneral assembly＝0；
Ic4＝Ic1+Ic2；
Ic5＝Ic1/Ic2；
Id1＝ACH2/ACH3＝A36/A37；
Id2＝A1H+2H/AExpansion of aromatic hydrogen＝(A8+A9+A10)/A38。
The calculation results of the respective infrared structural parameters are shown in table 21.
(7) And comparing the relative height of the infrared structural parameter values of the coal sample with that of other coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of the coal sample according to the characterization significance of each parameter.
TABLE 20 area and assignment of each of the fitted sub-peaks of example 7
TABLE 21 calculated values of various infrared structural parameters of example 7
I of embodiments one to seven of the present inventiona1Value and dry base ash content Ad、Ib3Value and dry basis hydrogen content HdAnd Ic4Value and dry oxygen content OdThe correlation between them is shown in fig. 15, 16 and 17, respectively. It can be seen that the calculated value of the infrared structural parameter introduced by the invention has a significant positive correlation with the current conventional coal quality analysis data, and the linear correlation coefficient r of the three groups of data20.9651, 0.9648 and 0.9202 are respectively reached, so that the reasonableness and the accuracy of the curve fitting data processing method adopted by the invention and the determined fitting sub-peak attribution are proved.
The embodiments described above are intended to enable those skilled in the art to fully understand and effectively use the invention. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above-mentioned embodiments, and modifications made by those skilled in the art according to the teachings of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.
Claims (4)
1. An infrared structural parameter method for coal quality analysis comprises the following steps:
(1) preparing a coal sample meeting infrared spectrum testing conditions, and adjusting a Fourier transform infrared spectrometer to meet testing parameters to finally obtain a coal sample original infrared spectrogram with a high signal-to-noise ratio;
(2) dividing an original infrared spectrogram into six wave bands by taking the lowest point of a corresponding wave trough of an original spectral line as a demarcation point according to specific wave number ranges of different functional groups in different vibration modes;
(3) respectively selecting a series of base points on the original spectral lines of the wave bands to define the base lines of the wave bands;
the base point is selected according to the following steps and principles: a. selecting demarcation points at two ends of a wave band; b. if the lowest point of the characteristic wave trough on the wave band original spectral line exists, selecting the lowest point of the characteristic wave trough on the wave band original spectral line, and ensuring that all coal samples are selected similarly at the similar positions of the original spectral line;
the baseline is determined according to the following steps and principles: a. connecting each pair of adjacent base points by line segments, wherein all the line segments form a base line of the wave band; b. if the lowest point of the trough below the baseline appears on the original spectral line, selecting the lowest point as a base point, and then re-determining the baseline according to the step a; if a non-valley point below the baseline appears on the original spectral line, zeroing the value;
(4) according to the principle that each trough of the second derivative of the original spectral line corresponds to a hidden peak in the original spectral line, curve fitting processing is carried out on the original spectral line of each wave band, overlapping parts among the peaks are separated, and a plurality of fitting sub-peaks are decomposed;
(5) calculating the area of each fitting sub-peak and determining the attribution of each fitting sub-peak;
(6) establishing and calculating a series of infrared structure parameters representing the relative content of a certain type of functional group structure by taking the sum of the areas of all fitting sub-peaks of all wave bands as a reference; simultaneously constructing and calculating two infrared structure parameters respectively representing the internal characteristics of the fatty component and the aromatic component;
(7) and comparing the relative height of the infrared structural parameter values of different coal samples, and comprehensively analyzing and evaluating the coal quality characteristics of each coal sample according to the characterization significance of each parameter.
2. The infrared structural parameter method for coal quality analysis according to claim 1, characterized in that: the wave number range of the original infrared spectrogram of the coal sample is 4000-400 cm-1(ii) a The six wave bands are 3720-3581 cm respectively-1、3099～2800cm-1、1874～1365cm-1、1334～950cm-1、950～671cm-1、622～439cm-1。
3. The infrared structural parameter method for coal quality analysis according to claim 1, characterized in that: the curve fitting treatment is carried out by adopting a Voigt distribution function and a way of fixing the peak position of the peak.
4. The infrared structural parameter method for coal quality analysis according to claim 3, characterized in that: the infrared structural parameters comprise:
ia1 ratio of the sum of the areas of the inorganic mineral vibratory peaks to the sum of the areas of all of the fitter peaks, i.e. AInorganic mineral/AGeneral assemblyCharacterizing the relative content of inorganic mineral substances in the coal;
ia2 ratio of sum of areas of vibrational peaks of clay-like minerals to sum of areas of peaks of all said fitter peaks, i.e. AClay mineral/AGeneral assemblyCharacterizing the relative content of clay minerals in the coal;
ib 1-ratio of the sum of the areas of the peaks of the aliphatic Hydrogen oscillation peaks to the sum of the areas of all of the fitted daughter peaks, namely AAliphatic hydrogen/AGeneral assemblyCharacterizing the relative content of fatty structures in the coal;
ib2 ratio of sum of areas of aromatic Hydrogen vibratory peaks to sum of areas of all of the fitted daughter peaks, AAromatic hydrogen/AGeneral assemblyCharacterizing the relative content of aromatic structures in the coal;
ib 3-ratio of sum of areas of aliphatic and aromatic hydrogen vibrational peaks to sum of areas of all of the fitter peaks, i.e. Ib1+Ib2Characterizing the relative content of total hydrogen in the coal;
ib4 ratio of sum of aliphatic hydrogen oscillation peak areas to sum of aromatic hydrogen oscillation peak areas, i.e. Ib1/Ib2The relative degree of the distribution proportion of hydrogen atoms in the coal between the aliphatic structure and the aromatic structure is represented;
ic 1-ratio of the sum of C-O vibrational peak areas for C-O single bonds to the sum of peak areas of all said fitters, i.e. AC—O/AGeneral assemblyRepresenting the relative content of carbon-oxygen single bond structure in the coal;
ic 2-ratio of the sum of the areas of the C-O vibrational peaks to the sum of the areas of all the fitter peaks, i.e. AC＝O/AGeneral assemblyRepresenting the relative content of the carbon-oxygen double bond structure in the coal;
ic 3-ratio of the sum of the areas of the vibrating peaks of the carboxylic acid groups COOH to the sum of the areas of the peaks of all said fitter molecules, i.e. ACOOH/AGeneral assemblyCharacterizing the relative content of carboxylic acid groups in the coal;
ic4, i.e. the ratio of the sum of the areas of the vibration peaks of C-O and C-O double bonds to the sum of the areas of the peaks of all the fitted sub-peaks, i.e. Ic1+ Ic2, characterizes the relative content of total oxygen in coal;
ic5, i.e. Ic1/Ic2, is the ratio of the sum of C-O vibration peak areas and C-O vibration peak areas, i.e. the relative proportion of oxygen atoms in coal between C-O and C-O structures;
id 1-ratio of CH2 vibratory peak area to CH3 vibratory peak area in fatty structures, i.e., ACH2/ACH3Characterizing the length or branching degree of the fatty side chain and the bridge bond in the coal, wherein the larger the parameter value is, the longer the fatty side chain and the bridge bond are, or the lower the branching degree is;
id2 ratio of sum of isolated or adjacent hydrogen oscillation peak area to aromatic hydrogen stretching oscillation peak area in aromatic structure, namely A1H+2H/AExpansion of aromatic hydrogenThe relative proportion of rings that characterize the degree of high substitution or condensation in an aromatic ring system.
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