Method for calculating direct coal liquefaction capacity
By constructing a basic coal quality database and combining indicators such as hydrogen-carbon atomic ratio, volatile matter, and ash content to screen liquefiable coals, the problem of large calculation errors in the direct coal liquefaction capacity of existing technologies has been solved, and accurate assessment of resource quantity and liquefaction conversion capacity has been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA COAL GEOLOGY GRP CO LTD
- Filing Date
- 2026-03-18
- Publication Date
- 2026-07-10
AI Technical Summary
The existing technology lacks a systematic and standardized calculation process for calculating the direct coal liquefaction capacity, resulting in large errors in the calculation results, which cannot meet the needs of industrialization and make it difficult to accurately select liquefiable coal and calculate resource quantities.
A basic coal quality database is constructed, and coals suitable for liquefaction are screened using indicators such as hydrogen-carbon atomic ratio, volatile matter, and ash content. Resource quantity and liquefaction conversion capacity are calculated by combining coal seam thickness and apparent density, and a standardized calculation method is provided.
It enables precise screening and resource calculation of liquefiable coal, reduces calculation errors, and improves the accuracy and reliability of calculation results. It is applicable to the assessment of direct coal liquefaction capacity in different regions and coal types.
Smart Images
Figure CN122369701A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of direct coal liquefaction technology, and in particular to a method for calculating the direct coal liquefaction capacity. Background Technology
[0002] Direct coal liquefaction (DCL) is a process that converts coal into liquid fuels through hydrocracking. It utilizes hydrogen and catalysts under high temperature and pressure conditions to crack coal into products such as gasoline and diesel. It is also known as the hydrocracking method for coal. Accurately calculating the direct liquefaction capacity of coal in a specific region is a core prerequisite for rationally planning resource utilization and improving the economics and stability of projects during the industrial layout, process optimization, and project feasibility studies for direct coal liquefaction.
[0003] In existing technologies, the calculation of direct coal liquefaction capacity mostly relies on empirical estimation or judgment based on a single coal quality index. A systematic, standardized, and highly operable calculation process has not been formed. In particular, there is a lack of precise screening standards for liquefiable coal and a linkage calculation logic between resource quantity and liquefaction conversion capacity. This results in large errors in the calculation results, which cannot provide reliable data support for resource assessment and process parameter setting for direct coal liquefaction projects. It is difficult to meet the needs of large-scale industrial plants for accurate resource accounting, thus limiting the large-scale promotion and optimized application of direct coal liquefaction technology.
[0004] Therefore, this invention is proposed. Summary of the Invention
[0005] The purpose of this invention is to provide a method for calculating the direct liquefaction capacity of coal. This method has a standardized process, is highly operable, and can accurately screen liquefiable coal, scientifically calculate the amount of liquefiable coal resources and liquefaction conversion capacity, thereby improving the accuracy and reliability of the calculation results.
[0006] This invention provides a method for calculating the direct coal liquefaction capacity, comprising the following steps: S1. Select the area for planar research and collect sample analysis and testing data at each stage within the research area; S2. Organize all coal seam test data in the study area and construct a basic coal quality database, which shall include at least industrial analysis data and elemental analysis data; S3. Filter the coal seam data in the coal quality database according to the criteria for coal suitable for liquefaction, and select the coals that can be liquefied; S4. Based on the sample distribution points corresponding to the liquefiable coal selected in step S3, delineate the distribution range S of the liquefiable coal, in units of 10,000 m³. 2 ; S5. Calculate the amount of liquefiable coal resources Q1, Q1 = S × H × D; where H is the average thickness of the coal seam in meters; and D is the average apparent density of the coal seam in tons per cubic meter (t / m³). 3; S6. Calculate the coal liquefaction conversion capacity Q, Q=Q1×r; where r is the yield of liquid products per 100 million tons.
[0007] Furthermore, the sample analysis and testing data in step S1 are the test data corresponding to coal samples from different coal seams, different depths, and different sampling points within the study area.
[0008] Furthermore, the industrial analysis data in step S2 includes moisture, ash, and volatile matter.
[0009] Furthermore, the elemental analysis data in step S2 includes carbon content and hydrogen content.
[0010] Furthermore, the coal quality database in step S2 also includes the sampling location, sampling depth, and coal seam number information of the coal samples.
[0011] Furthermore, in step S2, if the collected test data is insufficient to support subsequent calculations, relevant data is supplemented to the coal quality database through sampling and testing.
[0012] Furthermore, the screening criteria in step S3 are: hydrogen-to-carbon atomic ratio > 0.75, volatile matter Vdaf ≥ 35%, and ash content Ad ≤ 12%.
[0013] The essence of direct coal liquefaction is the cracking and hydrogenation of large hydrocarbon molecules in coal under external conditions, transforming them into small liquid products. The hydrogen-to-carbon ratio (H / C) directly reflects the hydrogenation potential and liquefaction feasibility of coal. If H / C ≤ 0.75, it indicates that the coal has a low hydrogen content and is rich in carbon, making hydrogenation difficult and difficult to transform into liquid products, or even unable to undergo an effective liquefaction reaction. Therefore, it is used as a basic indicator for determining whether coal is suitable for liquefaction.
[0014] Volatile matter is a gaseous and liquid product produced by the decomposition of coal at high temperatures. Its content is directly related to the complexity of the coal's molecular structure. When the volatile matter content is ≥35%, the proportion of easily cracked small molecular components in the coal is moderate, and cracking reactions are likely to occur during liquefaction, generating intermediate products that can be converted into liquid products. If the volatile matter content is <35%, the coal is hard and has a dense molecular structure, making cracking difficult and liquefaction efficiency extremely low, which does not meet the core requirements for liquefiable coal.
[0015] Ash, consisting of non-combustible inorganic impurities in coal such as quartz and clay, not only does not participate in the liquefaction process but also poses two major problems: first, it covers the active sites of the catalyst, reducing its catalytic efficiency and increasing energy consumption and costs; second, it easily deposits in the reaction system, causing equipment wear, pipeline blockage, and affecting production continuity. Controlling the ash content to ≤12% can minimize the interference of inorganic impurities on the liquefaction reaction, ensuring the stable and efficient operation of the liquefaction process.
[0016] This invention clarifies the precise screening criteria for liquefiable coal, and combines industrial analysis and elemental analysis data for dual control, which can accurately distinguish between liquefiable and non-liquefiable coal, avoid interference from ineffective coal resources in the calculation results, and lay a precise data foundation for subsequent calculation of resource quantity and liquefaction capacity.
[0017] Furthermore, in step S5, the average thickness and average apparent density of coal seams within the distribution range of liquefiable coal are obtained by surveying or consulting relevant geological data.
[0018] Furthermore, in step S6, the value of r ranges from 12.8% to 33%.
[0019] The lower limit of 12.8% for r corresponds to an extremely reasonable scenario of low liquefaction efficiency in industrial production. This mainly targets low-activity coal types, such as some lean coals and semi-lean coals, with an H / C ratio close to 0.75, volatile matter slightly higher than 35%, conventional liquefaction processes, and ordinary catalysts. In this case, the coal cracking and hydrogenation conversion rates are low, and the liquid product yield is at the industry-recognized reasonable lower limit. This value is derived from measured data from existing industrial demonstration plants. Below 12.8%, liquefaction is economically unfeasible and has no practical application value; therefore, it is used as the lower limit.
[0020] The upper limit of 33% for r corresponds to an optimized scenario with high liquefaction efficiency in industrial production. This mainly targets highly reactive coal types, such as bituminous coal and lignite, with a high H / C ratio, sufficient volatile matter, optimized liquefaction processes, and efficient catalysts. In this case, the coal cracking and hydrogenation reactions are more complete, and the liquid product yield can reach a relatively high level in the industry. This value is also based on industrial measured data. Above 33%, due to the limitations of the coal's own molecular structure, even under optimal conditions, some large carbon molecules in the coal cannot be completely converted into liquid products. In addition, due to the constraints of reaction thermodynamics and kinetics, it is impossible to achieve a higher liquefaction yield. Therefore, this value is used as the upper limit.
[0021] The universality of the r value range: The yield of direct coal liquefaction is affected by three core factors: coal type, process parameters, and catalyst activity, and the yield varies greatly under different scenarios. A range of 12.8% to 33% can comprehensively cover the actual yield range of existing industrial and demonstration plants, including both ordinary yields under normal conditions and the upper and lower limits under extreme optimization or normal scenarios. This is suitable for the calculation needs of different research areas and different liquefiable coals in this invention, avoiding the inability to adapt to multiple scenarios due to an overly narrow value range, or the distortion of calculation results due to an overly wide value range.
[0022] This invention clarifies a reasonable range for the yield r of liquid products and determines specific values based on coal type, process conditions, and catalyst type. It balances the universality and specificity of the calculation method, and can adapt to the calculation needs of direct coal liquefaction capacity in different regions and for different coal types, thus having a wide range of applications.
[0023] In summary, compared with the prior art, the present invention has the following beneficial effects: The technical solution provided by this invention fills the gap in the existing technology for calculating the direct coal liquefaction capacity, which lacks a systematic and standardized process. It constructs a complete linkage process of "data collection - database construction - screening of liquefiable coal - delineation of distribution range - resource quantity calculation - liquefaction capacity calculation". The process has clear logic and strong operability, gets rid of the limitations of traditional experience estimation or single indicator judgment, ensures the standardization and uniformity of the calculation process, significantly reduces calculation errors, and improves the accuracy of calculating the amount of liquefiable coal resources and liquefaction conversion capacity. Attached Figure Description
[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0025] Figure 1 This is a flowchart illustrating the calculation process in an embodiment of the present invention. Detailed Implementation
[0026] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0027] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0028] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0029] Example A method for calculating the direct coal liquefaction capacity, such as... Figure 1 As shown, the specific steps are as follows: S1. The selected area for the planar study is a coal mine field with clear geographical boundaries. By reviewing the geological exploration report and sampling records of the coal mine, we collect coal sample analysis data from different coal seams (coal seam No. 3, coal seam No. 5, coal seam No. 8), different stages, different depths, and different sampling points within the study area to ensure that the data covers all major mineable coal seams and areas at different depths within the study area.
[0030] S2. All collected coal seam test data were categorized and organized, and abnormal data such as those with excessive detection errors and missing sampling point information were removed to construct a basic coal quality database. This database includes industrial analysis data and elemental analysis data. The industrial analysis data includes moisture, ash, and volatile matter, while the elemental analysis data includes carbon and hydrogen content. Supplementary information such as sampling point coordinates, sampling depth, and coal seam number was also entered to facilitate subsequent traceability and analysis. Upon review, it was found that sampling data was missing in some areas of coal seam No. 5, insufficient to support the screening of liquefiable coal in that area. Borehole sampling was used to supplement the sampling, and the data was tested according to GB / T 212-2008 "Industrial Analysis Methods for Coal" and GB / T 476-2001 "Elemental Analysis Methods for Coal". The supplemented test data was then entered into the basic coal quality database to ensure the accuracy and completeness of the data.
[0031] S3. Screen all coal seam data in the coal quality database one by one to screen coals that can be liquefied. The screening criteria are hydrogen-to-carbon atomic ratio > 0.75, volatile matter Vdaf ≥ 35%, and ash content Ad ≤ 12%. The hydrogen-to-carbon atomic ratio is calculated by the ratio of the mass fraction of hydrogen to the mass fraction of carbon in the elemental analysis data. Volatile matter is based on dry ash-free volatile matter, and ash content is based on air-dried ash content.
[0032] S4. Extract all sample distribution points corresponding to the liquefiable coal screened in step S3, and delineate the distribution range S of the liquefiable coal. After measurement and calculation, the distribution range S of the liquefiable coal is 8.6 million m³. 2 .
[0033] S5. By investigating the coal mine's production reports and reviewing the geological survey report, the average thickness H and average apparent density D of the coal seams within the distribution range of liquefiable coal were obtained. Specifically, the average thickness of coal seam No. 3 was 4.2m, No. 5 was 3.8m, and No. 8 was 5.1m. Based on these calculations, the average thickness H of the coal seams within the distribution range of liquefiable coal was determined to be 4.3m. The average apparent density D of the coal seams, determined through sampling and measurement combined with geological data, was 1.35 t / m³. 3 The amount of liquefiable coal resources Q1 is calculated using the formula Q1=S×H×D. Substituting the data, we get: Q1=860×4.3×1.35=49.923 million t≈0.5 billion tons.
[0034] S6. Calculate the coal liquefaction conversion capacity Q. The calculation formula is Q=Q1×r, where r is the yield of liquid products in 100 million tons. Combining the characteristics of the coal type that can be liquefied in this embodiment, the selected direct coal liquefaction process, and the catalyst used, the value of r is determined to be 30%. Substituting the data, we can calculate: Q=0.50×30%=0.15 billion tons, that is, the direct coal liquefaction capacity in this study area is 0.15 billion tons of liquid products.
[0035] It should be noted that the value of r in this embodiment is only an example. In actual applications, it can be flexibly adjusted according to the specific coal type, liquefaction process parameters, catalyst type, etc., and the value range can be controlled within 12.8%~33%. At the same time, the selection of the planar study range can be adjusted according to actual needs, and the sampling and testing standards must strictly follow the relevant national standards to ensure the standardization and accuracy of the data.
[0036] The technical solution provided by this invention ensures the integrity, accuracy, and consistency of coal quality data by constructing a basic coal quality database. Combined with a scientific resource quantity calculation formula, it significantly reduces calculation errors and improves the accuracy of calculating liquefiable coal resources and liquefaction conversion capacity. This invention fills the gap in existing technologies regarding the lack of a systematic and standardized process for calculating direct coal liquefaction capacity. It constructs a complete and interconnected process of "data collection - database construction - liquefiable coal screening - distribution range delineation - resource quantity calculation - liquefaction capacity calculation." The process logic is clear and highly operable, overcoming the limitations of traditional experience-based estimations or single-indicator judgments, and ensuring the standardization and uniformity of the calculation process.
[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for calculating the direct coal liquefaction capacity, characterized in that, Includes the following steps: S1. Select the area for planar research and collect sample analysis and testing data at each stage within the research area; S2. Organize all coal seam test data in the study area and construct a basic coal quality database, which shall include at least industrial analysis data and elemental analysis data; S3. Filter the coal seam data in the coal quality database according to the criteria for coal suitable for liquefaction, and select the coals that can be liquefied; S4. Based on the sample distribution points corresponding to the liquefiable coal selected in step S3, delineate the distribution range S of the liquefiable coal, in units of 10,000 m³. 2 ; S5. Calculate the amount of liquefiable coal resources Q1, Q1 = S × H × D; where H is the average thickness of the coal seam in meters; and D is the average apparent density of the coal seam in tons per cubic meter (t / m³). 3 ; S6. Calculate the coal liquefaction conversion capacity Q, Q=Q1×r, where r is the yield of liquid products per 100 million tons.
2. The calculation method according to claim 1, characterized in that, The sample analysis and testing data in step S1 are the test data corresponding to coal samples from different coal seams, different depths, and different sampling points within the study area.
3. The calculation method according to claim 1, characterized in that, The industrial analysis data in step S2 includes moisture, ash, and volatile matter.
4. The calculation method according to claim 1, characterized in that, The elemental analysis data in step S2 includes carbon content and hydrogen content.
5. The calculation method according to claim 1, characterized in that, The coal quality database in step S2 also includes the sampling location, sampling depth, and coal seam number information of the coal samples.
6. The calculation method according to claim 1, characterized in that, In step S2, if the collected test data is insufficient to support subsequent calculations, relevant data will be supplemented to the coal quality database through sampling and testing.
7. The calculation method according to claim 1, characterized in that, The screening criteria in step S3 are: hydrogen-to-carbon atomic ratio > 0.75, volatile matter Vdaf ≥ 35%, and ash content Ad ≤ 12%.
8. The calculation method according to claim 1, characterized in that, In step S5, the average thickness and average apparent density of coal seams within the distribution range of liquefiable coal are obtained by surveying or consulting relevant geological data.
9. The calculation method according to claim 1, characterized in that, In step S6, the value of r ranges from 12.8% to 33%.