Coal calorific value calculation method and system

Abstract

The invention relates to the field of coal, in particular to a coal heat calculation method and system. The method comprises the following steps: based on a known coal sample database, optimizing and pre-storing organic matter molecular structure model parameter sets corresponding to different coal types; when the calorific value of the to-be-measured coal sample is calculated, acquiring the coal type, element content and ash content data of the to-be-measured coal sample; calling a corresponding pre-stored parameter set according to the coal type; high-sulfur coal or low-sulfur coal is divided according to the substance amount relation of the sulfur element and Fe / Ti, and the mineral substance heat absorption amount Q mineral substance is calculated according to the fact that mineral substance elements are distributed to a preset chemical reaction library; determining the number of core structure units and alkyl side chains in the organic matter through an amount conservation equation of organic carbon and hydrogen substances, and calculating the calorific value Q of the organic matter; calculating a comprehensive calorific value based on a formula Qv = Q organic matter-Q mineral; the defects that a traditional method is poor in universality and does not consider influences of sulfur and mineral substances are overcome, errors are small, and the industrial coal sample heat calculation requirement is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of coal, in particular to a coal calorific value calculation method and system. BACKGROUND

[0002] Coal, as an important energy resource, its calorific value is a core index to measure the value of coal energy and economic properties, directly affecting coal quality classification, combustion efficiency, cost accounting and environmental protection indicators. At present, the methods for determining the calorific value of coal mainly include experimental measurement method, empirical formula method and statistical analysis method. However, these methods have obvious limitations: the experimental measurement method has high accuracy, but requires professional equipment and a long test period; the use of multiple linear regression, artificial neural network method to study the correlation between ash content, volatile matter and other industrial analysis data and calorific value, the empirical formula obtained lacks universality, and is only applicable to specific regions, coal mines or coal types.

[0003] Therefore, it is of great significance to develop a coal calorific value calculation method that can comprehensively consider the influence of mineral chemical reaction, organic matter molecular structure and sulfur form, to improve the efficiency and accuracy of industrial coal quality analysis. SUMMARY

[0004] The present application provides a coal calorific value calculation method and system, which can comprehensively consider the organic matter molecular structure, mineral element composition and chemical reaction type of coal, and has high accuracy and universality.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions: A coal calorific value calculation method, comprising the following steps: Data acquisition step: acquiring the basic data of the coal sample to be measured, including coal type, carbon (C), hydrogen (H), sulfur (S) element mass content, and ash content and mass percentage of oxides in ash; Parameter calling step: according to the coal type of the coal sample to be measured, calling the pre-stored corresponding organic matter molecular structure model parameter set, the parameter set including core structure unit parameters (RN, a, b), average number of carbon atoms L1 of alkyl side chain and its corresponding combustion heat value G5, and average number of bridging bonds L2; Heat absorption calculation step: according to the amount-of-substance relationship of sulfur (S), iron (Fe) and titanium (Ti) elements in coal, high-sulfur coal or low-sulfur coal is divided; the mineral elements are distributed to the preset chemical reaction library, the heat of each reaction and the amount of substance are calculated to obtain the total heat absorption Q of the mineral elements 矿物质 ; Heat calculation step: using the called organic matter molecular structure model parameter set, through the amount of substance conservation equation of organic carbon and organic hydrogen, the number of core structure units x and the number of alkyl side chains y are determined, and the heat of combustion of the core structure unit and the heat of combustion of the alkyl side chain G5 are added to obtain the heat of organic matter Q 有机质 ; The comprehensive heat calculation step is based on the formula: Q v =Q 有机质 -Q 矿物质 , the comprehensive heat Q v is obtained.

[0006] Further, the pre-stored organic matter molecular structure model parameter set is called, and the establishment of the parameter set includes: Sample database establishment step: obtaining the basic data of a plurality of groups of dry basis coal samples with known heat; Parameter optimization step: traversing the preset value combination of core structure unit parameters (RN, a, b), average number of carbon atoms L1 of alkyl side chain, and average number of bridging bonds L2; for each parameter combination, calculate the heat calculation value of each coal sample in the sample database; taking the absolute error, root mean square error (RMSE) and multiple determination coefficient (R 2 ) between the calculated value and the measured value as evaluation indexes, the optimal parameter combination is screened out; Parameter storage step: storing the optimal parameter combination and the corresponding coal type to form the parameter set.

[0007] Further, the coal type includes anthracite, bituminous coal and lignite; the mass content of carbon (C), hydrogen (H) and sulfur (S) elements is represented by B1, B2 and D1 respectively, and the mass content of ash is represented by A0; the oxides in the ash include silicon dioxide, aluminum oxide, iron oxide, calcium oxide, magnesium oxide, sodium oxide, potassium oxide, phosphorus pentoxide, titanium dioxide and sulfur trioxide, and the mass percentage of the oxides in the ash is represented by A1-A 10 .

[0008] Further, the high-sulfur coal or low-sulfur coal is divided according to the amount of substance relationship of sulfur (S), iron (Fe) and titanium (Ti) in coal; specifically including: The Fe and Ti elements in the coal preferentially form the compound FeTiO3, and the remaining Fe and S form the compound FeS2. Comparing the amount of substance of Fe and S at this time, if the amount of substance of S is higher than that of Fe: (n Fe -n FeTiO3 )<0.5n S , it is divided into high-sulfur coal, and the remaining S is distributed to organic S; If the amount of substance of S is lower than that of Fe: (n Fe -n FeTiO3 )>0.5nS , the remaining Fe forms compound FeCO3.

[0009] Further, the reactions in the chemical reaction library include: kaolinite Al2Si2O5(OH)4 decomposes into SiO2, Al2O3 and H2O, illite K 0.8 Al2(Si, Al)4O 10 (OH)2 decomposes into K2O, Al2O3, SiO2 and H2O, FeS2 is oxidized to Fe2O3 and SO2, CaCO3 decomposes into CaO and CO2, MgCO3 decomposes into MgO and CO2, FeTiO3 is oxidized to Fe2O3 and TiO2.

[0010] Further, the core unit structure is composed of RNbenzene rings, including (a-(y / x+L2)) -CH (aromatic) functional groups, (b+(y / x+L2)) -C- (aromatic) functional groups, (a-(y / x+L2)) H atoms; the combustion heat value of the core structure unit is calculated according to the combustion heat value of its functional groups as follows: Δ c H m =(-544.59)kJ / mol×(a-(y / x+L2))+(-393.51)kJ / mol×(b+(y / x+L2) =-[(544.59a+393.51b)-151.08(y / x+L2)]kJ / mol, Where: RN represents the number of benzene rings forming the core structure unit, a represents the number of -CH (aromatic) functional groups in each core structure unit, b represents the number of -C- (aromatic) functional groups in each core structure unit; y is the total number of alkyl side chains, x is the total number of core structure units, y / x represents the average number of alkyl side chains connected to each core structure unit; L2 represents the average number of bridging bonds in each core structure unit; the number of benzene rings RN takes an integer value of 1 to 12.

[0011] Further, each alkyl side chain is composed of L1C atoms and (2L1+1) H atoms; each core structure unit contains (a+b) C atoms, (a-(y / x+L2)) H atoms; the amount of substance conservation equation of organic carbon and hydrogen elements includes: The amount of substance B of organic carbon in coal 11 =n C B 12 =(0.08333B1-B12 ) mol = (a + b) x + L1y, The amount of substance n of organic hydrogen in coal H = B2 mol = (a - (y / x + L2)) x + (2L1 + 1) y, Wherein, a represents the number of -CH (aromatic) functional groups in each core structural unit, b represents the number of -C- (aromatic) functional groups in each core structural unit; y is the total number of alkyl side chains, x is the total number of core structural units; L1 represents the average number of carbon atoms of alkyl side chains in each core structural unit; L2 represents the average number of bridging bonds in each core structural unit; L1 is 0.5-1, 1.5-2, 2.5-3, 3.5-4, 4.5-5, 5.5-6, 6.5-7, and the value is accurate to one decimal place.

[0012] The application also provides a coal calorific value calculation system, comprising: A data acquisition module is configured to acquire basic data of a coal sample to be measured, including coal type, mass content of carbon (C), hydrogen (H), and sulfur (S) elements, and mass content of ash and mass percentage of oxides in ash; A parameter calling module is configured to call a pre-stored corresponding organic matter molecular structure model parameter set according to the coal type of the coal sample to be measured, wherein the parameter set includes core structural unit parameters (RN, a, b), average number of carbon atoms L1 of alkyl side chains, and corresponding combustion heat value G5, and average number of bridging bonds L2; A heat absorption calculation module is configured to divide high-sulfur coal or low-sulfur coal according to the amount of substance relationship of sulfur (S), iron (Fe), and titanium (Ti) elements in coal; distribute mineral elements to a pre-set chemical reaction library; calculate the heat of each mineral according to the combustion heat and amount of substance of each reaction; and sum up to obtain total heat absorption Q of mineral substances. 矿物质 ; A calorific value calculation module is configured to determine the number of core structural units x and the number of alkyl side chains y by using the called organic matter molecular structure model parameter set and through the amount of substance conservation equation of organic carbon and organic hydrogen; and add the combustion heat value of the core structural unit and the combustion heat value G5 of the alkyl side chain to obtain the calorific value Q of organic matter. 有机质 ; A comprehensive calorific value module is configured to obtain the comprehensive calorific value Q based on the formula: Q v = Q 有机质 - Q 矿物质 . v .

[0013] Further, the coal calorific value calculation system of the application comprises a parameter storage module configured to store organic matter molecular structure model parameter sets corresponding to different coal types. And further comprising an establishing module for constructing the parameter set of the organic matter molecular structure model, the establishing of the parameter set comprising: Sample database establishment: obtaining basic data of a plurality of groups of dry base coal samples with known heat release; Parameter optimization: traversing preset value combinations of core structure unit parameters (RN, a, b), average number of carbon atoms L1 of alkyl side chains, and average number L2 of bridging bonds; for each parameter combination, calculating the heat release calculation value of each coal sample in the sample database; taking the absolute error, root mean square error (RMSE), and multiple determination coefficient (R 2 ) between the calculation value and the measured value as evaluation indexes, and screening the optimal parameter combination; Parameter storage: storing the optimal parameter combination in association with the corresponding coal type to form the parameter set.

[0014] Further, the core unit structure is composed of RN benzene rings, including (a-(y / x+L2)) -CH (aromatic) functional groups, (b+(y / x+L2)) -C- (aromatic) functional groups, and (a-(y / x+L2)) H atoms. Wherein: RN represents the number of benzene rings in the core structure unit, a represents the number of -CH (aromatic) functional groups in each core structure unit, b represents the number of -C- (aromatic) functional groups in each core structure unit; y is the total number of alkyl side chains, x is the total number of core structure units, y / x represents the average number of alkyl side chains connected to each core structure unit; L2 represents the average number of bridging bonds in each core structure unit; the number of benzene rings RN takes an integer from 1 to 12.

[0015] Beneficial effects: High accuracy: The method comprehensively considers the organic matter molecular structure model of coal, the composition of mineral elements and the chemical reaction type, not only considers the heat release of organic matter of coal, but also analyzes the heat absorption of mineral matter in the combustion process and the influence of sulfur element, which can more accurately calculate the heat release of coal, with small measured absolute error, meeting the requirements of industrial coal sample heat calculation.

[0016] Strong universality: Through different core structure unit and average carbon atom number matching rules of alkyl side chains, the chemical composition and structural characteristics of different coal types can be adapted, and the method is basically applicable to coal samples with carbon content of more than 40%.

[0017] The coal heat release calculation system provided by the application has systematic design, and through the collaborative work of the data acquisition module, the heat absorption calculation module, the heat release calculation module and the comprehensive heat release module, the automatic calculation of the coal heat release is realized, and the calculation efficiency and accuracy are improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only constitute some of the embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0019] Fig. 1 The flow chart of the coal calorific value calculation method of the present application is shown in the figure. Fig. 2 The schematic diagram of the core structure unit with straight chain arrangement of benzene ring and the core structure unit with the most compact arrangement of benzene ring when RN is 3 is shown in the figure. DETAILED DESCRIPTION

[0020] In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0021] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly disposed on the other element; when an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0022] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0023] In addition, the terms "first", "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of", "several" is two or more, unless otherwise specifically limited.

[0024] It is to be understood that the structures, proportions, sizes, etc. shown in the drawings accompanying the present specification are shown by way of illustration only and are meant to be exemplary in nature, and are not to be taken in a limiting sense. Any modification in structure, change in proportions, combination of elements or parts, and / or substitution of elements or parts, and the like, which do not depart from the spirit of the present application, are intended to be within the scope of the present application.

[0025] The embodiments of the present application are written in a progressive manner.

[0026] Referring to Figs. 1-2 A coal calorific value calculation method, comprising the following steps: Data acquisition step: acquiring the basic data of the coal sample to be measured, including the type of coal, the mass content of carbon (C), hydrogen (H), sulfur (S) elements, and the mass content of ash and the mass percentage of oxides in the ash; Parameter calling step: according to the type of the coal sample to be measured, calling a pre-stored corresponding organic matter molecular structure model parameter set, the parameter set including core structure unit parameters (RN, a, b), average number of carbon atoms L1 of alkyl side chain and its corresponding combustion heat value G5, and average number of bridging bonds L2; Heat absorption calculation step: according to the amount-of-substance relationship of sulfur (S), iron (Fe), and titanium (Ti) elements in the coal, high-sulfur coal or low-sulfur coal is divided; the mineral elements are distributed to a pre-set chemical reaction library, the heat of each mineral is calculated according to the combustion heat and the amount of substance of each reaction, and the total heat absorption Q of the mineral is summed up. 矿物质 ; Calorific value calculation step: using the called organic matter molecular structure model parameter set, the number of core structure units x and the number of alkyl side chains y are determined through the amount-of-substance conservation equation of organic carbon and organic hydrogen, and the calorific value of the organic matter Q is obtained by adding the combustion heat value of the core structure unit and the combustion heat value G5 of the alkyl side chain. 有机质 ; Comprehensive calorific value calculation step, based on the formula: Q v =Q 有机质 -Q 矿物质 , the comprehensive calorific value Q v is obtained.

[0027] The method has high calculation accuracy and strong universality; the molecular structure model of organic matter, the composition of mineral elements and the chemical reaction type are comprehensively considered, not only the heat value of the organic matter of the coal is considered, but also the heat absorption of the mineral matter in the combustion process and the influence of the sulfur element are analyzed in detail, so that the heat value of the coal can be more accurately calculated, the absolute error is small in actual measurement, and the industrial coal sample heat calculation requirements are met; in addition, through the matching rules of different core structure unit and average carbon atom number of alkyl side chain, the chemical composition and structural characteristics of different coal types can be adapted, and the method is basically applicable to the calculation of coal samples with carbon content of more than 40%.

[0028] Further, a pre-stored organic matter molecular structure model parameter set is called, and the establishment of the parameter set includes: A sample database establishment step: obtaining basic data of a plurality of groups of dry base coal samples with known heat values; A parameter optimization step: traversing a preset value combination of core structure unit parameters (RN, a, b), average carbon atom number L1 of alkyl side chain and average number L2 of bridging bonds; for each parameter combination, calculating the heat value calculation value of each coal sample in the sample database; taking the absolute error, root mean square error (RMSE) and multiple determination coefficient (R 2 ) between the calculation value and the measured value as evaluation indexes, and screening the optimal parameter combination; A parameter storage step: storing the optimal parameter combination in association with the corresponding coal type to form the parameter set.

[0029] Further, the coal type includes anthracite, bituminous coal and lignite; the mass content of carbon (C), hydrogen (H) and sulfur (S) elements is respectively represented by B1, B2 and D1, and the mass content of ash is represented by A0; the oxides in the ash include silicon dioxide, di-aluminum trioxide, di-iron trioxide, calcium oxide, magnesium oxide, sodium oxide, potassium oxide, di-phosphorus pentoxide, titanium dioxide and sulfur trioxide, and the mass percentage of the oxides in the ash is represented by A1-A 10 .

[0030] Further, the high-sulfur coal or low-sulfur coal is divided according to the amount-of-substance relationship of sulfur (S), iron (Fe) and titanium (Ti) elements in the coal; specifically including: The Fe and Ti elements in the coal preferentially form a compound FeTiO3, the remaining Fe and S form a compound FeS2, and the amount-of-substance of Fe and S is compared, if the amount-of-substance of S is higher than that of Fe: (n Fe -n FeTiO3 )<0.5n S , the coal is divided into high-sulfur coal, and the remaining S is distributed to organic S; If the amount-of-substance of S is lower than that of Fe: (n Fe -n FeTiO3 )>0.5n S, the remaining Fe forms the compound FeCO3.

[0031] Further, the reactions in the chemical reaction library include: Decomposition of kaolinite Al2Si2O5(OH)4 into SiO2, Al2O3 and H2O, Decomposition of illite K 0.8 Al2(Si,Al)4O 10 (OH)2 into K2O, Al2O3, SiO2 and H2O, Oxidation of FeS2 into Fe2O3 and SO2, Decomposition of CaCO3 into CaO and CO2, Decomposition of MgCO3 into MgO and CO2, Oxidation of FeTiO3 into Fe2O3 and TiO2.

[0032] Further, the core structure unit consists of RN number of benzene rings, including (a-(y / x+L2)) -CH (aromatic) functional groups, (b+(y / x+L2)) -C- (aromatic) functional groups, (a-(y / x+L2)) H atoms; the combustion heat value of the core structure unit is calculated according to the combustion heat value of its functional groups as follows: Δ c H m =(-544.59)kJ / mol×(a-(y / x+L2))+(-393.51)kJ / mol×(b+(y / x+L2) =-[(544.59a+393.51b)-151.08(y / x+L2)]kJ / mol, Where: RN represents the number of benzene rings forming the core structure unit, a represents the number of -CH (aromatic) functional groups in each core structure unit, b represents the number of -C- (aromatic) functional groups in each core structure unit; y is the total number of alkyl side chains, x is the total number of core structure units, y / x represents the average number of alkyl side chains connected to each core structure unit; L2 represents the average number of bridging bonds in each core structure unit.

[0033] Further, the mass conservation equation of organic carbon and organic hydrogen includes: The mass of organic carbon in coal B 11 =n C -B 12 =(0.08333B1-B 12 ) mol = (a+b)x+L1y, The mass of organic hydrogen in coal n H =B2 mol = (a-(y / x+L2))x+(2L1+1)y, wherein a represents the number of -CH (aromatic) functional groups in each core structural unit, b represents the number of -C- (aromatic) functional groups in each core structural unit; y is the total number of alkyl side chains, x is the total number of core structural units; L1 is the average number of carbon atoms of alkyl side chains in each core structural unit; L2 represents the average number of bridging bonds in each core structural unit.

[0034] As a feasible way, the present application obtains the mass content of mineral elements in coal from the way of "oxide in ash" to calculate the coal calorific value. The representation method of each mass content is shown in Table 1:

[0035] The carbon element in coal includes organic carbon and inorganic carbon; the sulfur element includes organic sulfur and inorganic sulfur; the object of calculation is a dry basis coal sample, so the mass content of hydrogen element is equal to the mass content of organic hydrogen.

[0036] For the convenience of understanding the present embodiment, the calculation of the calorific value of 1g dry basis coal sample is taken as an example for illustration: If the mass content of carbon in 1g coal is equal to 80%, then B1=0.80g; if the mass content of SiO2 in coal ash is equal to 50%, then A1=0.5; in the calculation process, other letters such as B2, D1, A1 are used similarly.

[0037] The amount of substance n of element C C =B1g÷12g / mol=0.08333B1mol=B 11 +B 12 ; The amount of substance n of element H H =B2g÷1g / mol=B2mol, the object of calculation is a dry basis coal sample, and the amount of substance of element hydrogen is equal to that of organic hydrogen; The amount of substance n of element S S =D1g÷32g / mol=0.03125D1mol=D3+D2; The mass m of ash A =1g×A0=A0g; The amount of substance n of SO3 in coal ash SO3 =A0g×A 10 ÷80.06g / mol=0.01249A0A 10 mol, the amount of substance n of SO2 converted into SO3 SO2 =0.01249A0A 10 mol; During the combustion of coal sample at 815℃, a part of alkali metals Na and K will be volatilized, so the amount of substance n of Na element in coalNa = 0.01613 A0A6 x 2 x (1 + 30%) = 0.04194 A0A6 mol; The amount of substance n of K element in coal K = 0.01062 A0A7 x 2 x (1 + 30%) = 0.02762 A0A7 mol; Based on the law of conservation of elements, the content conversion between oxides and elements is shown in Table 2: Table 2

[0038] There are mainly five categories of mineral matter in coal: clay minerals (about 60%-80% of the total amount of mineral matter, mainly kaolinite Al2Si2O5(OH)4, illite K 0.8 Al2(Si,Al)4O 10 (OH)2, and sericite K{Al2[Si3AlO 10 ](OH)2}), sulfides (pyrite FeS2, marcasite FeS and magnetite Fe 1-x S, a small amount of flash zinc ore ZnS, galena PbS and chalcopyrite CuFeS2 in most coal seams), phosphates (apatite Ca5F(PO4)3, Ca5OH(PO4)3, Ca5Cl(PO4)3), carbonates (mainly for the same mineral siderite FeCO3, dolomite CaMg(CO3)2, metamorphic stage mainly for calcite CaCO3, iron dolomite (Fe, Ca, Mg)CO3), sulfates (alkali metal, alkaline earth metal and iron sulfate and complex salt); According to the composition of mineral matter in coal, the types of chemical reactions that may occur when the mineral matter is burned at high temperature are inferred, for example, kaolinite loses crystal water at 327°C to convert to metakaolin, and decomposes into needle-shaped r -Al2O3 and mullite (3Al2O3·2SiO2); the thermal decomposition of calcite (CaCO3, MgCO3) includes two independent reactions, calcium carbonate begins to decompose into calcium oxide and carbon dioxide at 650°C, and magnesium carbonate begins to decompose into magnesium oxide and carbon dioxide at 590°C.

[0039] The composition of mineral matter is simplified in this application, for example, K 0.8 Al2(Si,Al)4O 10(OH)2 represents the chemical composition of illite (in fact, illite represents a silicate mineral with a similar mica layer structure, and there is no accurate molecular formula). At the same time, the chemical reactions that occur during high-temperature combustion are also complex, and the chemical reactions of various minerals are mutually influenced and difficult to distinguish. The present application defines that the chemical reactions that occur during the combustion of various minerals are independent of each other, and the reaction products are common stable oxides, so that the types of chemical reactions in which each mineral is involved and their combustion heat values are determined.

[0040] The chemical reactions of minerals in coal during combustion and the combustion heat values are shown in Table 3. Since kaolinite Al2Si2O5(OH)4 and illite K 0.8 Al2(Si,Al)4O 10 (OH)2 is a mixture, only the range value of the combustion heat thereof is obtained; the chemical reaction library is shown in Table 3: Table 3

[0041] Table 3 shows that if each element is in a different compound, different chemical reactions will occur during combustion, and the combustion heat is different. In particular, the sulfur element in coal is a complex existence, including organic sulfur and inorganic sulfur. According to the different mass contents of S elements, the coal samples are divided into high-sulfur coal and low-sulfur coal.

[0042] In the present application, it is defined that the Fe and Ti elements in coal preferentially form the compound FeTiO3, and the remaining Fe and S form the compound FeS2. The amount of substance of Fe and S at this time is compared.

[0043] If the amount of substance of S is higher than that of Fe (high-sulfur coal), the remaining S is distributed to organic S, that is, (n Fe -n FeTiO3 )=<0.5n S , (0.01252A0A3-0.01252A0A9) mol=<0.01562D1 mol; If the amount of substance of S is lower than that of Fe (low-sulfur coal), the remaining Fe forms the compound FeCO3; that is, (n Fe -n FeTiO3 )>0.5n S , (0.01252A0A3-0.01252A0A9) mol>0.01562D1 mol; specifically, (i) high-sulfur coal, (n Fe -n FeTiO3 )=<0.5n S The Ti in coal is attributed to the compound FeTiO3, and the amount of substance thereof is 0.01252A0A9 mol; Fe in coal due to compounds FeTiO3 and FeS2, the amount of substance of FeS2 = (0.01252A0A3 - 0.01252A0A9) mol; S in coal due to compounds FeS2 and organic S, The amount of substance of organic S = (0.03125D1 - 0.02504A0A3 + 0.02504A0A9) mol; Si in coal due to mixture Al2Si2O5(OH)4 (kaolinite), the amount of substance of SiO2 in clay = 0.01664A0A1 mol; Al in coal due to mixture Al2Si2O5(OH)4 (kaolinite), the amount of substance of Al2O3 in clay = 0.00981A0A2 mol; P in coal due to compound Ca5(PO4)3F, the amount of substance thereof = 0.004697A0A8 mol; Ca in coal due to compounds Ca5(PO4)3F and CaCO3, The amount of substance of CaCO3 = (0.01783A0A4 - 0.02348A0A8) mol; Mg in coal due to compound MgCO3, the amount of substance thereof = 0.02481A0A5 mol; Na in coal due to compound Na2CO3, the amount of substance thereof = 0.02097A0A6 mol; K in coal due to compound K2CO3, the amount of substance thereof = 0.01381A0A7 mol; The amount of substance of SO3 in coal ash n SO3 = A0g x A 10 ÷ 80.06 g / mol = 0.01249A0A 10 mol, the amount of substance of SO2 converted into SO3 n SO2 = 0.01249A0A 10 mol; Inorganic carbon in coal is derived from CaCO3, MgCO3, Na2CO3 and K2CO3, the amount of substance thereof: B 12 = (0.01783A0A4 - 0.02348A0A8) + 0.02481A0A5 + 0.02097A0A6 + 0.01381A0A7 mol; According to the heat value of combustion of the chemical reactions of the mineral substances in Table 3, Table 4 shows the change in heat generated by the chemical reactions of each compound:

[0044]

[0045] From Table 4 above, the heat absorption of coal is equal to the heat change generated by the chemical reaction of minerals and element S, and the heat absorption of coal is: Q 矿物质 = 2.496A0A1+1.4715A0A2-(10.4442A0A3-10.4442A0A9) +(3.1826A0A4-4.1912A0A8)+2.8928A0A5+6.7356A0A6+5.4688A0A7 +5.2216A0A8+0.5321A0A9-1.2365A0A 10 -(9.25D1-7.4118A0A3+7.4118A0A9)kJ.

[0046] (ii) low-sulfur coal, (n Fe -n FeTiO3 )>0.5n S Ti in coal is due to the compound FeTiO3, and the amount of substance thereof = 0.01252A0A9 mol; S in coal is due to the compound FeS2, and the amount of substance thereof = 0.01562D1 mol; Fe in coal is due to the compounds FeTiO3, FeS2, and FeCO3, the amount of substance of FeCO3 = (0.01252A0A3-0.01252A0A9-0.01562D1) mol; Si in coal is due to the mixture Al2Si2O5(OH)4 (kaolinite), and the amount of substance of SiO2 in clay = 0.01664A0A1 mol; Al in coal is due to the mixture Al2Si2O5(OH)4 (kaolinite), and the amount of substance of Al2O3 in clay = 0.00981A0A2 mol; P in coal is due to the compound Ca5(PO4)3F, and the amount of substance thereof = 0.004697A0A8 mol; Ca in coal is due to the compounds Ca5(PO4)3F and CaCO3, the amount of substance of CaCO3 = (0.01783A0A4-0.02348A0A8) mol; Mg in coal is due to the compound MgCO3, and the amount of substance thereof = 0.02481A0A5 mol; Na in coal is due to the compound Na2CO3, and the amount of substance thereof = 0.02097A0A6 mol; The K in coal is attributed to the compound K2CO3, and the amount of substance thereof = 0.01381A0A7 mol; The inorganic carbon in coal is derived from CaCO3, MgCO3, Na2CO3, K2CO3 and FeCO3, and the amount of substance thereof is: B 12 = (0.01783A0A4-0.02348A0A8) + 0.02481A0A5 + 0.02097A0A6 + 0.01381A0A7 + (0.01252A0A3-0.01252A0A9-0.01562D1) mol; According to the combustion heat value of the mineral chemical reaction in Table 3, Table 5 shows the heat change generated by the chemical reaction of each compound: Table 5

[0047] From the above Table 5, the heat absorption of coal is equal to the heat change generated by the chemical reaction of minerals, and the heat absorption of coal is: Q 矿物质 = 2.496A0A1 + 1.4715A0A2-13.0302D1 + (3.1826A0A4-4.1912A0A8) + 2.8928A0A5 + 6.7356A0A6 + 5.4688A0A7 + 5.2216A0A8 + 0.5321A0A9-1.2365A0A 10 - (0.7212A0A3-0.7212A0A9-0.8997D1) kJ; In the above manner of the present application, the coal is divided into high-sulfur coal and low-sulfur coal for separate treatment, thereby improving the accuracy of the calculation of the heat absorption of minerals.

[0048] The heat of coal is mainly provided by C and H in organic matter. From the perspective of the molecular structure of coal (the precise molecular structure of coal is unknown, and the present application is expressed by means of an organic matter molecular structure model), carbon atoms in different chemical environments have different combustion heats. Based on the combustion heat and the Gay-Lussac law, the heat of organic matter is calculated in combination with the molecular structure of coal. Coal has the characteristics of a polymer, and is a mixture of a series of "similar compounds" with similar but not completely identical molecular weights and molecular structures. The "similar compounds" are referred to as "basic structural units", which include regular parts and irregular parts. The regular parts are referred to as core structural units, which are composed of several or ten benzene rings, aliphatic rings, hydrogenated aromatic rings and heterocyclic rings (containing nitrogen, oxygen and sulfur). The irregular parts refer to alkyl side chains and various functional groups connected around the core structural units.

[0049] The present application simplifies the organic matter structure of coal, and only core structure units and alkyl side chains constitute the organic matter structure. The core structure units are connected with the alkyl side chains, the core structure units are connected through bridging bonds to form a two-dimensional structure, and the two-dimensional layers are connected through intermolecular forces to form a three-dimensional structure.

[0050] The present application constructs a series of core structure units, each of which is a derivative composed of different numbers of benzene rings. Define RN as the number of benzene rings in the core structure unit, RN is an integer from 1 to 12; the number of -CH (aromatic) functional groups in each core structure unit is a, and the number of -C- (aromatic) functional groups is b.

[0051] For example, the core structure unit composed of 3 benzene rings has RN=3. If the 3 benzene rings are freely combined without considering the stability of the chemical structure, 2 isomers can be formed, as shown in Fig. 2 . Fig. 2 The left core structure unit has 10 -CH (aromatic) functional groups and 4 -C- (aromatic) functional groups, i.e. a=10 and b=4. Fig. 2 The right core structure unit has 9 -CH (aromatic) functional groups, i.e. a=9; the carbon atom at the center point in the defined structure is classified as a -C- (aromatic) functional group, i.e. there are only two types of functional groups, -CH (aromatic) and -C- (aromatic), in a core structure unit, and the number of -C- (aromatic) functional groups is equal to the total number of carbon atoms minus the number of -CH (aromatic) functional groups; the total number of carbon atoms in this core structure unit is 13, so the number of -C- (aromatic) functional groups is 4, i.e. b=4.

[0052] The 76 core structure units can be expressed by three parameters: the number of benzene rings (RN), the number of -CH (aromatic) functional groups (a), and the number of -C- (aromatic) functional groups (b). For example, 5 benzene rings are freely combined to form a core structure unit (RN=5). The number of -CH (aromatic) functional groups in the straight-chain core structure unit is 14 (a=14), and the number of -C- (aromatic) functional groups is 8 (b=8). The number of -CH (aromatic) functional groups in the most compact core structure unit formed by 5 benzene rings is 11 (a=11), and the number of -C- (aromatic) functional groups is 8 (b=8). Therefore, the number of core structure units formed by 5 benzene rings is 4 (=14-11+1). The number of -C- (aromatic) functional groups in the straight-chain core structure unit and the most compact core structure unit is the same, so the number of -C- (aromatic) functional groups in the other two core structure units between the straight-chain core structure unit and the most compact core structure unit is also 8 (b=8), and the number of -CH (aromatic) functional groups decreases to 13 and 12, respectively. Therefore, the four core structure units can be represented by the parameters RN=5, a=14, b=8; RN=5, a=13, b=8; RN=5, a=12, b=8; and RN=5, a=11, b=8.

[0053] Therefore, the number of core structure units formed by different numbers of benzene rings is related to the number of -CH (aromatic) functional groups in the straight-chain core structure unit and the most compact core structure unit, i.e., the number of core structure units is equal to the difference between the a values of the two core structure units plus one.

[0054] The method for representing the number of -CH (aromatic) functional groups (a) and the number of -C- (aromatic) functional groups (b) in a core structure unit is as follows: when the value of RN is specified, the number of -CH (aromatic) functional groups (a) and the number of -C- (aromatic) functional groups (b) in the straight-chain core structure unit and the most compact core structure unit can be obtained from Table 6. The a values of the other core structure units between the straight-chain core structure unit and the most compact core structure unit decrease from the a value of the straight-chain core structure unit to the a value of the most compact core structure unit. The a value is an integer, and the b value is equal to the b value of the straight-chain core structure unit or the most compact core structure unit. The number of core structure units corresponding to each RN and the a values and b values of the 76 core structure units are shown in Table 6.

[0055] Table 6

[0056] The average number of carbon atoms in the alkyl side chain is defined as L1, and the value of L1 and its corresponding alkyl side chain functional group and heat of combustion G5 are shown in Table 7, for example, when L1 = 0.5 or L1 = 0.9, the corresponding alkyl side chain functional group is both methyl (-CH3), and the heat of combustion G5 is both -672.46 kJ / mol; the average number of bridging bonds is L2 (L2 >= 2); the sum of L1 and L2 is less than the number of -CH (aromatic) functional groups (a).

[0057] The heat of combustion of the organic functional group is estimated by the average value of the heat of combustion of simple compounds or the difference between the heat of combustion of two compounds, for example: The heat of combustion of the -CH (aromatic) functional group is equal to one-sixth of the heat of combustion of benzene, that is, Δ c H m = -3267.54 kJ / mol ÷ 6 = -544.59 kJ / mol; The heat of combustion of the -C- (aromatic) functional group is equal to the heat of combustion of graphene, Δ c H m = -393.51 kJ / mol; The heat of combustion of the -CH3 functional group is equal to the difference between the heat of combustion of toluene and benzene, that is, Δ c H m = (-3940) kJ / mol - (-3267.54) kJ / mol = -672.46 kJ / mol; The heat of combustion corresponding to the alkyl side chain is G5, and the heat of combustion values of the organic functional groups are shown in Table 7: Table 7

[0058] It can be understood that the coal organic matter is defined as having x core structure units and y alkyl side chains, the core structure units form a two-dimensional layer through bridging bonds, and the two-dimensional layers form a three-dimensional structure through intermolecular forces. Assuming that the H atoms in the core structure unit are not substituted by alkyl side chains and bridging bonds, it has a-CH (aromatic) functional group and a-C- (aromatic) functional group. In fact, the core structure unit will be connected to the alkyl side chain and the bridging bond, so each core structure unit has an average of y / x alkyl side chains, so the core structure unit has (a-(y / x+L2)) -CH (aromatic) functional groups and (b+(y / x+L2)) -C- (aromatic) functional groups. When the core structure unit forms a two-dimensional structure through bridging bonds, the core structure unit loses L2 (L2 >= 2) H atoms in two spatial dimensions, i.e. L2 -CH (aromatic) functional groups are converted to -C- (aromatic) functional groups. Its heat of combustion: Δ c Hm = (-544.59) kJ / mol x (a - (y / x + L2)) + (-393.51) kJ / mol x (b + (y / x + L2)) = -[(544.59a + 393.51b) - 151.08(y / x + L2)] kJ / mol The heat of combustion of the organic matter is calculated as follows: The average number of carbon atoms in the alkyl side chain is L1, and the molecular formula is C L1 H 2L1+1 Each alkyl side chain consists of L1 C atoms and (2L1 + 1) H atoms. Each core structural unit contains (a + b) C atoms and (a - (y / x + L2)) H atoms. The organic matter contains x core structural units and y alkyl side chains, and thus the following binary equation is obtained: The amount of substance B of the organic carbon in the coal 11 = n C -B 12 = (0.08333B1 - B 12 ) mol = (a + b)x + L1y The amount of substance n of the organic hydrogen in the coal H = B2 mol = (a - (y / x + L2))x + (2L1 + 1)y x = (2B 11 -B2) / (a + 2b + L2), y = B 11 / L1 - [(2a + 2b)B 11 - (a + b)B2] / [(a + 2b)L1 + L1L2] The heat of combustion of the organic matter is equal to the heat of combustion of the core structural units and the heat of combustion of the alkyl side chains, i.e. Q 有机质 = [(544.59a + 393.51b) - 151.08(y / x + L2)] kJ / mol x x mol + G5 kJ / mol x y mol = (544.59a + 393.51b - 151.08L2)x + (G5 - 151.08)y kJ The heat of combustion of the organic matter is related to the number of benzene rings (RN) in the core structural units, the number of -CH (aromatic) functional groups (a), the number of -C- (aromatic) functional groups (b), the average number of carbon atoms in the alkyl side chain (L1), the heat of combustion of the functional groups of the alkyl side chain (G5), the average number of bridging bonds (L2), and the like.

[0059] A set of parameters is determined as follows: ① According to Table 6, all values of RN, a, and b are input, i.e. 76 structures are input as follows: RN=1, a=6, b=0; RN=2, a=8, b=2; RN=3, a=10, b=4; RN=3, a=9, b=4; ... RN=7, a=18, b=12; RN=7, a=17, b=12; RN=7, a=16, b=12; RN=7, a=15, b=12; ... RN=12, a=19, b=22; RN=12, a=18, b=22; RN=12, a=17, b=22; RN=12, a=16, b=22.

[0060] ②According to Table 7, input all values of L1, which are 0.5~1, 1.5~2, 2.5~3, 3.5~4, 4.5~5, 5.5~6, 6.5~7 (take one decimal place, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0) and the corresponding G5; ③Input all values of L2, which are 2=<L2<=(a-L1), take one decimal place, for example, 2, 2.1, 2.2,..., 3, 3.1, 3.2,..., (a-L1-2), (a-L1-1), (a-L1); ④Input the proximate analysis (calorific value, ash content and oxide content in ash) and elemental analysis data (carbon, hydrogen and sulfur content) of n groups (n>0) of dry and anthracite coal samples. The n groups of anthracite coal data should include coal sample data in Northeast, North China, East China, Northwest, Southwest and Central South regions, and the coal sample data in each region should be divided into intervals of no more than 0.3 kJ / g of calorific value, and each interval should contain at least 5 coal sample data.

[0061] ⑤Input the organic matter calorific value calculation equation: Q 有机质 =[(544.59a+393.51b)-151.08(y / x+L2)]kJ / mol×xmol+G5kJ / mol×ymol =(544.59a+393.51b-151.08L2)x+(G5-151.08)ykJ; x=(2B 11 -B2) / (a+2b+L2), y=B 11 / L1-[(2a+2b)B 11 -(a+b)B2] / [(a+2b)L1+L1L2]; ⑥Input the mineral matter heat absorption calculation equation: High-sulfur coal: Q 矿物质 = 2.496A0A1+1.4715A0A2-(10.4442A0A3-10.4442A0A9)+(3.1826A0A4-4.1912A0A8)+2.8928A0A5+6.7356A0A6+5.4688A0A7+5.2216A0A8+0.5321A0A9-1.2365A0A 10 -(9.25D1-7.4118A0A3+7.4118A0A9)kJ; Low-sulfur coal: Q 矿物质 =2.496A0A1+1.4715A0A2-13.0302D1+(3.1826A0A4-4.1912A0A8)+2.8928A0A5+6.7356A0A6+5.4688A0A7+5.2216A0A8+0.5321A0A9-1.2365A0A 10 -(0.7212A0A3-0.7212A0A9-0.8997D1)kJ; ⑦Calculate the heat of n groups of dry basis anthracite Q v =Q 有机质 -Q 矿物质 ; Each group of parameters (RN, a, b, L1, G5, L2) will obtain the heat of n groups of dry basis coal samples, and the difference between the calculated heat and the oxygen bomb calorimeter measured heat is calculated, that is, the absolute error. The root mean square error (RMSE) and the complex correlation coefficient (R 2 ) are introduced to evaluate the calculation accuracy of the heat calculation model. The closer the RMSE is to 0, the smaller the deviation between the calculated heat and the measured heat; the closer the R 2 is to 1, the better the linearity of the heat calculation model, and the higher the model fitting degree. Record which group of parameters has the smallest root mean square error (RMSE) and the highest complex correlation coefficient (R 2 ), that is, the parameters for calculating the heat of anthracite.

[0062] Root mean square error: ; Complex correlation coefficient: ; Residual sum of squares: ; Total sum of squares: ; y i : the measured heat of the i-th coal sample; : the calculated heat of the i-th coal sample; : the average value of the measured heat of n coal samples; n: the total number of coal samples; (8) input the proximate analysis (ash content and oxide content in ash) and elemental analysis data (carbon, hydrogen, and sulfur content) of the unknown dry basis anthracite sample; (9) bring the anthracite heat calculation parameters (RN, a, b, L1, G5, L2) into step (5) to calculate the heat of organic matter, and bring the data in (8) into (6) to calculate the heat absorption of mineral matter.

[0063] The heat of the unknown dry basis anthracite sample Q v = Q 有机质 - Q 矿物质 ; The method for determining the parameters (RN, a, b, L1, G5, L2) for calculating the heat of bituminous coal and lignite is the same as that for anthracite.

[0064] In summary, the scheme can calculate the heat change of mineral matter and S element in coal, which is not only related to the content of mineral matter metal elements (Si, Al, Fe, Ca, Mg, Na, K, Ti) and non-metal elements (S, P) in coal, but also related to the specific chemical reaction in which the element participates; and can calculate the heat change of organic matter in coal, which is not only related to the average number of carbon atoms of the core structure unit and the alkyl side chain, but also affected by mineral matter elements (inorganic carbon). At the same time, based on the idea of "the heat of coal is equal to the heat of organic matter minus the heat absorption of mineral matter", the heat of coal under constant volume (constant volume high heat) is: Q v = Q 有机质 - Q 矿物质 ; Specifically, based on the heat calculation formula of coal, the heat of 30 groups of dry basis bituminous coal in various places in China is calculated, and the proximate analysis and elemental analysis information of the 30 groups of coal samples are as shown in Table 8: Table 8

[0065] The oxide content in the coal ash is shown in Table 9:

[0066] A group of bituminous coal parameters RN=5, a=11, b=8, L1=3.9, G5=2562.46 kJ / mol, L2=5.5 are used to calculate the heat of organic matter. At the same time, the sulfur (organic sulfur and inorganic sulfur) in the coal is classified, and the heat absorption of mineral matter is calculated. The heat of the 30 groups of bituminous coal, the absolute error, and the relative error are shown in Table 10. The maximum absolute error, the maximum relative error, and the correlation coefficient (R 2) is 0.9927, and the root mean square error (RMSE) is 0.30 kJ / g. The actual test case verifies that the scheme design of the application has no significant error compared with the national standard test method.

[0067]

[0068] The application also provides a coal calorific value calculation system, comprising: A data acquisition module is configured to acquire basic data of a coal sample to be measured, including coal type, mass content of carbon (C), hydrogen (H), and sulfur (S) elements, and mass content of ash and mass percentage of oxides in the ash; A parameter calling module is configured to call a pre-stored corresponding organic matter molecular structure model parameter set according to the coal type of the coal sample to be measured, wherein the parameter set comprises core structure unit parameters (RN, a, b), average number of carbon atoms L1 of alkyl side chains, and corresponding combustion heat value G5, and average number of bridging bonds L2; A heat absorption calculation module is configured to divide high-sulfur coal or low-sulfur coal according to the amount-of-substance relationship of sulfur (S), iron (Fe), and titanium (Ti) elements in the coal; distribute mineral elements to a pre-set chemical reaction library; calculate the heat of each mineral according to the combustion heat and amount of substance of each reaction; and sum the heat to obtain total heat absorption Q of the minerals. 矿物质 ; A calorific value calculation module is configured to determine the number of core structure units x and the number of alkyl side chains y by using the called organic matter molecular structure model parameter set, the amount-of-substance conservation equation of organic carbon and organic hydrogen, and the combustion heat value of the core structure unit and the combustion heat value G5 of the alkyl side chain, and add the values to obtain the calorific value Q of the organic matter. 有机质 ; A comprehensive calorific value module is configured to obtain the comprehensive calorific value Q based on the formula: Q v = Q 有机质 -Q 矿物质 . v

[0069] Further, the coal calorific value calculation system of the application comprises a parameter storage module configured to store organic matter molecular structure model parameter sets corresponding to different coal types. Further, the coal calorific value calculation system of the application comprises a parameter storage module configured to store organic matter molecular structure model parameter sets corresponding to different coal types. Sample database establishment: acquiring basic data of a plurality of dry base coal samples with known calorific values; ​Parameter optimization: traverse preset value combinations of core structure unit parameters (RN, a, b), average number of carbon atoms L1 of alkyl side chains, and average number of bridging bonds L2; for each parameter combination, calculate the calculated calorific value of each coal sample in the sample database; take the absolute error, root mean square error (RMSE), and multiple determination coefficient (R 2 ) between the calculated value and the measured value as evaluation indexes, and screen out the optimal parameter combination; Parameter storage: store the optimal parameter combination in association with the corresponding coal type to form the parameter set.

[0070] Further, the core unit structure is composed of RN benzene rings, including (a-(y / x+L2)) -CH (aromatic) functional groups, (b+(y / x+L2)) -C- (aromatic) functional groups, and (a-(y / x+L2)) H atoms. wherein RN represents the number of benzene rings in the core structure unit, a represents the number of -CH (aromatic) functional groups in each core structure unit, b represents the number of -C- (aromatic) functional groups in each core structure unit, y is the total number of alkyl side chains, x is the total number of core structure units, y / x represents the average number of alkyl side chains connected to each core structure unit, and L2 represents the average number of bridging bonds in each core structure unit; the number of benzene rings RN takes an integer from 1 to 12.

[0071] The above description of disclosed embodiments enables one of ordinary skill in the art to make or use the application. Various modifications to these embodiments will be readily apparent to those of ordinary skill in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Accordingly, the application is not to be limited to the embodiments shown herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of calculating the calorific value of coal, characterized by, The method comprises the following steps: A data acquisition step: acquiring the basic data of the coal sample to be tested, including the type of coal, the mass content of carbon (C), hydrogen (H), and sulfur (S) elements, and the mass content of ash and the mass percentage of oxides in the ash; A parameter calling step: calling a pre-stored corresponding organic matter molecular structure model parameter set according to the type of the coal sample to be tested, wherein the parameter set comprises core structure unit parameters (RN, a, b), the average number of carbon atoms L1 of an alkyl side chain and the corresponding combustion heat value G5, and the average number of bridging bonds L2; The heat absorption amount calculation step: according to the amount of substance relation of sulfur (S), iron (Fe) and titanium (Ti) elements in the coal, high-sulfur coal or low-sulfur coal is divided; the mineral elements are distributed to the preset chemical reaction library, the heat of each reaction and the amount of substance are calculated to obtain the total heat absorption amount Q of the mineral elements 矿物质 ; Heat calculation step: using the called organic matter molecular structure model parameter set, through the amount of substance conservation equation of organic carbon and organic hydrogen, the number of core structure units x and the number of alkyl side chains y are determined, and based on the combustion heat value of the core structure unit and the combustion heat value G5 of the alkyl side chain, the heat value Q of the organic matter is obtained by adding 有机质 ; The total heat generation is calculated based on the formula: Q v = Q 有机质 - Q 矿物质 , to obtain the total heat generation Q v .

2. The coal calorific value calculation method according to claim 1, characterized by, The pre-stored organic matter molecular structure model parameter set is established by the following steps: A sample database establishment step: acquiring the basic data of a plurality of groups of dry base coal samples with known heat generation; Parameter optimization step: traverse the preset core structure unit parameters (RN, a, b), the average number of carbon atoms L1 of alkyl side chain, and the average number L2 of bridging bonds; for each set of parameter combination, calculate the calculated calorific value of each coal sample in the sample database; take the absolute error, root mean square error (RMSE) and complex determination coefficient (R 2 ) between the calculated value and the measured value as the evaluation index, and screen out the optimal parameter combination; A parameter storage step: storing the optimal parameter combination in association with the corresponding coal type to form the parameter set.

3. The coal calorific value calculation method according to claim 2, characterized by, The coal type includes anthracite, bituminous coal and lignite; the mass content of carbon (C), hydrogen (H) and sulfur (S) elements is respectively represented by B1, B2 and D1, and the mass content of ash is represented by A0; the oxides in the ash include silicon dioxide, di-aluminum trioxide, di-iron trioxide, calcium oxide, magnesium oxide, sodium oxide, potassium oxide, di-phosphorus pentoxide, titanium dioxide and sulfur trioxide, and the mass percentage of the oxides in the ash is respectively represented by A1-A 10 .

4. The coal calorific value calculation method according to any one of claims 1 to 3, characterized by, The high-sulfur coal or low-sulfur coal is divided according to the amount-of-substance relationship of sulfur (S), iron (Fe), and titanium (Ti) elements in the coal, and specifically comprises: Fe and Ti elements in the coal preferentially form the compound FeTiO3, and the remaining Fe and S form the compound FeS2. Comparing the amounts of Fe and S at this time, if the amount of S is higher than that of Fe: (n Fe -n FeTiO3 )=<0.5n S , it is classified as high-sulfur coal, and the remaining S is distributed to organic S; If S is lower than the amount of substance of Fe: (n Fe -n FeTiO3 )>0.5n S , the coal is classified as low-sulfur coal, and the remaining Fe forms the compound FeCO3.

5. The coal calorific value calculation method according to claim 4, characterized by, The reactions in the chemical reaction library include: Decomposition of kaolinite Al2Si2O5(OH)4 into SiO2, Al2O3, and H2O, Illite K 0.8 Al2(Si,Al)4O 10 (OH)2decomposes into K2O, Al2O3, SiO2and H2O, Oxidation of FeS2 into Fe2O3 and SO2, Decomposition of CaCO3 into CaO and CO2, Decomposition of MgCO3 into MgO and CO2, Oxidation of FeTiO3 into Fe2O3 and TiO2.

6. The coal calorific value calculation method according to claim 5, characterized by, The core unit structure is composed of RN benzene rings, including (a-(y / x+L2)) -CH (aromatic) functional groups, (b+(y / x+L2)) -C- (aromatic) functional groups, and (a-(y / x+L2)) H atoms; and the combustion heat value of the core structure unit is calculated according to the combustion heat value formula of the functional groups as follows: Δ c H m = (-544.59) kJ / mol x (a - (y / x + L2)) + (-393.51) kJ / mol x (b + (y / x + L2)) =-[(544.59a+393.51b)-151.08(y / x+L2)] kJ / mol, wherein RN represents the number of benzene rings in the formation of the core structure unit, a represents the number of -CH (aromatic) functional groups in each core structure unit, b represents the number of -C- (aromatic) functional groups in each core structure unit, y is the total number of alkyl side chains, x is the total number of core structure units, y / x represents the average number of alkyl side chains connected to each core structure unit, and L2 represents the average number of bridging bonds in each core structure unit; the number of benzene rings RN takes an integer from 1 to 12.

7. The method of calculating the calorific value of coal according to claim 6, characterized by, Each alkyl side chain is composed of L1 C atoms and (2L1+1) H atoms; each core structure unit contains (a+b) C atoms and (a-(y / x+L2)) H atoms; and the amount-of-substance conservation equation of organic carbon and hydrogen elements comprises: amount of substance B of organic carbon in coal 11 = n C -B 12 = (0.08333B1-B 12 ) mol = (a + b)x + L1y, Amount of substance n of organic hydrogen in coal H = B2 mol = (a - (y / x + L2)) x + (2L1 + 1) y, Wherein, a represents the number of -CH (aromatic) functional groups in each core structural unit, b represents the number of -C- (aromatic) functional groups in each core structural unit; y is the total number of alkyl side chains, x is the total number of core structural units; L1 represents the average number of carbon atoms of alkyl side chain in each core structural unit; L2 represents the average number of bridging bonds in each core structural unit; L1 is valued at 0.5~1, 1.5~2, 2.5~3, 3.5~4, 4.5~5, 5.5~6, 6.5~7, and the value is accurate to one decimal place.

8. A coal calorific value calculation system characterized by comprising: Comprise: Data acquisition module, for acquiring the basic data of the coal sample to be measured, including coal type, carbon (C), hydrogen (H), sulfur (S) element mass content, and ash content and mass percentage of oxides in ash; Parameter calling module, for calling the pre-stored corresponding organic matter molecular structure model parameter set according to the coal type of the coal sample to be measured, the parameter set comprising core structural unit parameters (RN, a, b), average carbon atom number L1 of alkyl side chain and its corresponding combustion heat value G5, average number L2 of bridging bonds; The heat absorption amount calculation module is used for dividing high-sulfur coal or low-sulfur coal according to the amount-of-substance relationship of sulfur (S), iron (Fe) and titanium (Ti) elements in coal; distributing mineral elements to a preset chemical reaction library, calculating the heat of each mineral according to the combustion heat and amount of substance of each reaction, and summing to obtain the total heat absorption amount Q of the mineral 矿物质 ; The heat release calculation module is used for determining the number of core structure units x and the number of alkyl side chains y by using the called parameter set of the organic matter molecular structure model, through the amount of substance conservation equation of organic carbon and organic hydrogen, and adding the combustion heat value of the core structure units and the combustion heat value G5 of the alkyl side chains to obtain the heat release Q of the organic matter 有机质 ; A comprehensive heat generation module for obtaining a comprehensive heat generation Q v =Q 有机质 -Q 矿物质 , based on the formula: v .

9. The coal calorific value calculation system according to claim 8, characterized by, Comprise parameter storage module, for storing the organic matter molecular structure model parameter set corresponding to different coal types; And also include the establishment module, the establishment module is used for the construction of the organic matter molecular structure model parameter set, the establishment of the parameter set comprises: Sample database establishment: acquiring the basic data of a plurality of groups of dry base coal samples with known calorific value; Parameter optimization: traverse the preset core structure unit parameters (RN, a, b), the average number of carbon atoms L1 of alkyl side chain, the average number L2 of bridging bonds; for each parameter combination, calculate the calorific value of each coal sample in the sample database; take the absolute error, root mean square error (RMSE) and complex determination coefficient (R 2 ) between the calculated value and the measured value as the evaluation index, and select the optimal parameter combination; Parameter storage: storing the optimal parameter combination in association with the corresponding coal type to form the parameter set.

10. The coal calorific value calculation system according to claim 9, wherein The core unit structure is composed of RN benzene rings, including (a-(y / x+L2)) -CH (aromatic) functional groups, (b+(y / x+L2)) -C- (aromatic) functional groups, and (a-(y / x+L2)) H atoms; Wherein: RN represents the number of benzene rings forming the core structural unit, a represents the number of -CH (aromatic) functional groups in each core structural unit, b represents the number of -C- (aromatic) functional groups in each core structural unit; y is the total number of alkyl side chains, x is the total number of core structural units, and y / x represents the average number of alkyl side chains connected to each core structural unit; L2 represents the average number of bridging bonds in each core structural unit; the number of benzene rings RN is an integer from 1 to 12.

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