In-situ regulation and control oil-rich coal pyrolysis method for oil gas volatile components of associated oil shale
By using the volatile oil and gas generated in the oil shale layer to regulate the pyrolysis reaction of oil-rich coal under the oil shale layer, the problems of low tar yield and high ash coke in the existing technology are solved, and the production of high-quality tar and high-quality coke is achieved, and the economics of the process is improved.
Patent Information
- Application Number
- CN202510150762.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-11
- Publication Date
- 2025-03-28
AI Technical Summary
Among the existing pyrolysis technologies of oil-rich coal, the yield of tar is low and the quality is poor. When oil shale and oil-rich coal are co-pyrolyzed, high-ash coke is easily generated, and the process is complex and economical.
By pyrolysis under the oil shale layer and on the oil-rich coal seam, the oil-gas volatiles generated in the oil shale layer are used to regulate the oil-rich coal pyrolysis reaction in situ, so as to improve the quality of tar and high-quality coke production.
The yield and quality of tars for pyrolysis of oil-rich coal has been significantly improved. The light oil content in tar increases, the heavy oil content decreases, the ash content of coke is effectively controlled, the process is simplified, and the economic benefits are improved.
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Figure CN119709240A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of coal chemical industry, and specifically relates to a method for in-situ regulation of pyrolysis of oil-rich coal by volatile matter of associated oil shale oil and gas. Background Art
[0002] Since the tar yield from direct pyrolysis of oil-rich coal is low and the heavy oil content is high, the quality of the tar obtained is poor. Hydropyrolysis of oil-rich coal can produce high-yield and high-quality tar, but the cost of hydrogenation of "hydrogen-rich" gases such as H2 and CH4 is high, resulting in poor economic benefits of coal hydropyrolysis technology. Oil shale contains rich potential oil and gas resources, and is cheap, high in volatility and high in H / C. It is an ideal solid hydrogen donor for coal hydropyrolysis. By transferring the "hydrogen-rich" components from oil shale to coal, significant changes in the yield and quality of tar and coal gas are achieved.
[0003] Oil shale is a high-ash solid fossil fuel, which is bound to introduce a large amount of ash during the co-pyrolysis process. While improving the yield and quality of oil and gas products, it also leads to the deterioration of coke quality. However, the existing co-pyrolysis of oil-rich coal and oil shale either ignores coke products or performs deashing pretreatments such as extraction, acid washing or flotation on oil shale before co-pyrolysis. Both studies have major problems: on the one hand, coke is the main product of coal pyrolysis, and its quality directly determines its technical and economic feasibility. Therefore, it is not feasible to produce high-ash coke by co-pyrolysis of coal and oil shale, and there is no prospect for technical promotion. At the same time, there is a certain difference in the pyrolysis window temperature between oil-rich coal and oil shale. Direct mixed pyrolysis will also cause over-pyrolysis of oil shale, resulting in secondary cracking reactions of oil shale volatiles, resulting in unnecessary energy and resource waste. On the other hand, although oil shale avoids producing high-ash coke after deashing, the pretreatment of oil shale increases the process flow, prolongs the production cycle, increases the initial investment and later production costs, and reduces the economic efficiency of the co-pyrolysis technology of oil-rich coal and oil shale. Summary of the invention
[0004] In view of the deficiencies and problems in the above-mentioned background technology, the object of the present invention is to provide a method for in-situ regulating the pyrolysis of oil-rich coal by using the volatile matter of associated oil shale oil and gas. The present invention proposes for the first time to use the pyrolysis volatile matter of associated oil shale to in-situ regulate the pyrolysis reaction of oil-rich coal, thereby significantly improving the yield and quality of coal tar from the pyrolysis of oil-rich coal.
[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows: A method for in-situ regulation of volatile matter in associated oil shale oil and gas for pyrolysis of oil-rich coal, comprising the following steps: An oil-rich coal seam is set on the oil shale layer, and then pyrolysis is carried out at 600~800℃, wherein the oil shale layer is in the lower layer and the oil-rich coal seam is in the upper layer, and the mass ratio of the oil shale layer to the oil-rich coal seam is 1:(1~3).
[0006] Preferably, during pyrolysis, shale oil and shale gas are separated out from the oil shale layer.
[0007] Preferably, the shale oil components include aromatic compounds, aliphatic compounds, heteroatom compounds, phenolic compounds and impurities.
[0008] Preferably, in terms of mass percentage, the content of aromatic compounds in shale oil is 10% to 15%, the content of aliphatic compounds is 20% to 25%, the content of heteroatom compounds is 40% to 45%, and the content of phenolic compounds is 15% to 18%.
[0009] Preferably, the O / C ratio in shale oil is between 0.10 and 0.16, and the H / C ratio is between 0.12 and 0.15.
[0010] Preferably, the components of the shale gas include H2, CH4, CO2, CO, hydrocarbons and inevitable impurity gases.
[0011] Preferably, in terms of volume percentage, the contents of H2, CH4, CO2, CO and hydrocarbons in shale gas are 35% to 45%, 20% to 30%, 18% to 22%, 8% to 10% and 2% to 5%, respectively.
[0012] Preferably, the O / C ratio in the shale gas is between 0.6 and 0.8, and the H / C ratio is between 1.2 and 1.5.
[0013] The present invention has the following beneficial effects: In the in-situ regulation of pyrolysis of oil-rich coal by associated oil shale oil and gas volatiles of the present invention, the oil shale layer is in the lower layer, and the oil-rich coal layer is in the upper layer. During the pyrolysis process, the oil and gas volatiles (mainly including shale oil and shale gas) generated in the oil shale layer will pass upward through the oil-rich coal layer, and the oil-rich coal layer can use the oil and gas volatiles generated in the oil shale layer to achieve in-situ quality-enhancing pyrolysis. Therefore, the technical solution of the present invention can make the oil and gas volatiles generated in the oil shale layer rise and be directly used by the oil-rich coal layer during pyrolysis, avoiding the secondary cracking reaction of the oil and gas volatiles generated in the oil shale layer. According to experiments, compared with the prior art, the tar yield obtained by the method of the present invention is 7.8%~10.5%, and the tar yield is relatively high. At the same time, the heavy oil content in the tar is relatively low, and the light oil content can reach 35%~54%, which greatly improves the quality of the obtained tar. In addition, since the oil shale layer is in the lower layer and the oil-rich coal layer is in the upper layer, the coke obtained by pyrolysis of the oil-rich coal layer is easy to separate from the pyrolysis solid residue of the oil shale layer, so the ash content in the coke is effectively controlled, so that the quality of the coke obtained by the method of the present invention is high. In addition, it can be seen from the process of the present invention that the process steps are relatively simple and short, the process cycle is shortened, and the quality of the obtained tar and coke is good, which increases the economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 This is a diagram showing the results of simulated distillation of tar obtained in Examples 1 to 3 of the present invention. DETAILED DESCRIPTION
[0015] The following examples are provided for a better understanding of the present invention, and are not limited to the best implementation mode described, nor are they intended to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the present invention with the features of other prior arts shall fall within the protection scope of the present invention. In addition, the technical features involved in the different implementation modes of the present invention described below may be combined with each other as long as they do not conflict with each other.
[0016] The method for in-situ regulation of pyrolysis of oil-rich coal by volatile matter of associated oil shale gas of the present invention comprises the following steps: An oil-rich coal seam is set on the oil shale layer, and then pyrolysis is carried out at 600~800℃, wherein the oil shale layer is in the lower layer and the oil-rich coal seam is in the upper layer, and the mass ratio of the oil shale layer to the oil-rich coal seam is 1:(1~3).
[0017] The above scheme of the present invention can also directly use oil-rich coal and oil shale associated ore, that is, one side of the associated ore is oil-rich coal and the other side is oil shale, wherein during pyrolysis, the oil shale mineralization layer is located below the oil-rich coal layer.
[0018] In the above scheme of the present invention, oil shale oil and gas volatiles are produced by a pyrolysis method. The oil shale oil and gas volatiles mainly include shale oil and shale gas. During the pyrolysis process, the oil shale oil and gas volatiles pass through the oil-rich coal seam to achieve in-situ quality-improving pyrolysis of the oil-rich coal, significantly improving the yield and quality of coal tar from the pyrolysis of the oil-rich coal.
[0019] Among them, the main components of shale oil are aromatic compounds, aliphatic compounds, heteroatom compounds, phenolic compounds, etc. In terms of mass percentage, aromatic compounds, aliphatic compounds, heteroatom compounds, and phenolic compounds account for 10%-15%, 20%-25%, 40%-45%, and 15%-18% in shale oil, respectively. The O / C ratio in shale oil is between 0.10-0.16, and the H / C ratio is between 0.12-0.15.
[0020] The main components of shale gas are H2, CH4, CO2, CO, hydrocarbons (denoted as C n H m) and inevitable impurity gases, in terms of volume percentage, H2, CH4, CO2, CO and hydrocarbons account for 35%-45%, 20%-30%, 18%-22%, 8%-10% and 2%-5% respectively. The O / C ratio in shale gas is between 0.6-0.8, and the H / C ratio is between 1.2-1.5.
[0021] Example 1 The method for in-situ regulation of volatile matter in associated oil shale oil and gas pyrolysis of oil-rich coal in this embodiment includes the following steps: An oil-rich coal layer is set on the oil shale layer, and then pyrolysis is carried out at 600°C, wherein the oil shale layer is in the lower layer and the oil-rich coal layer is in the upper layer, and the mass ratio of the oil shale layer to the oil-rich coal layer is 1:1. In this embodiment, in terms of mass percentage, in the shale oil precipitated from the oil shale, the proportions of aromatic compounds, aliphatic compounds, heteroatom compounds, and phenolic compounds in the shale oil are 12%, 20%, 45%, and 15%, respectively, and the remainder is unavoidable impurities; the O / C ratio in the shale oil is 0.16, and the H / C ratio is 0.12. In terms of volume percentage, the H2, CH4, CO2, CO and C in shale gas are n H m The proportions are 35%, 30%, 18%, 8% and 5% respectively, and the remainder is inevitable impurity gas; the O / C ratio in shale gas is 0.8 and the H / C ratio is 1.2.
[0022] After the experiment was completed, the yield of coal tar from pyrolysis of oil-rich coal in this embodiment was 7.8%, and the tar composition was shown in Table 1: Table 1
[0023] From the results in Table 1, it can be seen that in the tar obtained in this embodiment, the contents of light oil, medium-quality oil and heavy oil account for 35%, 40% and 25% respectively. The simulated distillation results show that the contents of light oil, phenol oil, naphthalene oil, washing oil anthracene oil and asphalt in the obtained coal tar are 7.9%, 4.1%, 6.2%, 14.8%, 25.3% and 41.7% respectively.
[0024] Example 2 The method for in-situ regulation of volatile matter in associated oil shale oil and gas pyrolysis of oil-rich coal in this embodiment includes the following steps: An oil-rich coal layer is set on the oil shale layer, and then pyrolysis is carried out at 700°C, wherein the oil shale layer is in the lower layer and the oil-rich coal layer is in the upper layer, and the mass ratio of the oil shale layer to the oil-rich coal layer is 1:2. In this embodiment, in terms of mass percentage, in the shale oil precipitated from the oil shale, the proportions of aromatic compounds, aliphatic compounds, heteroatom compounds, and phenolic compounds in the shale oil are 13%, 22%, 42%, and 17%, respectively, and the remainder is unavoidable impurities; the O / C ratio in the shale oil is 0.14, and the H / C ratio is 0.13. In terms of volume percentage, the H2, CH4, CO2, CO and C in shale gas are n H m The proportions are 40%, 26%, 20%, 9% and 4% respectively, and the remainder is inevitable impurity gas; the O / C ratio in shale gas is 0.7 and the H / C ratio is 1.3.
[0025] After the experiment was completed, the yield of coal tar from pyrolysis of oil-rich coal in this embodiment was 8.5%, and the tar composition was shown in Table 2: Table 2
[0026] From the results in Table 2, it can be seen that in the tar obtained in this embodiment, the contents of light oil, medium-quality oil and heavy oil account for 42%, 38% and 20% respectively. The simulated distillation results show that the contents of light oil, phenol oil, naphthalene oil, washing oil anthracene oil and asphalt in the obtained coal tar are 7.4%, 4.1%, 5.4%, 10.4%, 25.8% and 46.8% respectively.
[0027] Example 3 The method for in-situ regulation of volatile matter in associated oil shale oil and gas pyrolysis of oil-rich coal in this embodiment includes the following steps: An oil-rich coal layer is set on the oil shale layer, and then pyrolysis is carried out at 800°C, wherein the oil shale layer is in the lower layer and the oil-rich coal layer is in the upper layer, and the mass ratio of the oil shale layer to the oil-rich coal layer is 1:3. In this embodiment, in terms of mass percentage, in the shale oil precipitated from the oil shale, the proportions of aromatic compounds, aliphatic compounds, heteroatom compounds, and phenolic compounds in the shale oil are 14%, 25%, 40%, and 18%, respectively, and the remainder is unavoidable impurities; the O / C ratio in the shale oil is 0.14, and the H / C ratio is 0.13. In terms of volume percentage, the H2, CH4, CO2, CO and C in shale gas are n H m The proportions are 45%, 20%, 22%, 10% and 2% respectively, and the remainder is inevitable impurity gas; the O / C ratio in shale gas is 0.7 and the H / C ratio is 1.3.
[0028] After the experiment was completed, the yield of coal tar from pyrolysis of oil-rich coal in this embodiment was 10.5%, and the tar composition was shown in Table 3: Table 3
[0029] From the results in Table 3, it can be seen that in the tar obtained in this embodiment, the contents of light oil, medium-quality oil and heavy oil account for 45%, 40% and 15% respectively. The simulated distillation results show that the contents of light oil, phenol oil, naphthalene oil, washing oil anthracene oil and asphalt in the obtained coal tar are 8.5%, 6.5%, 6.5%, 15.3%, 26.3% and 36.9% respectively.
[0030] From the above scheme, it can be seen that the present invention proposes for the first time to use the pyrolysis volatiles of associated oil shale to in-situ control the pyrolysis reaction of oil-rich coal, significantly improving the yield and quality of coal tar from the pyrolysis of oil-rich coal. The technology of the present invention lays the foundation for the in-situ pyrolysis technology of oil-rich coal and oil shale, and is expected to achieve clean, low-carbon and efficient utilization of oil-rich coal and oil shale resources, fully recover the potential oil and gas resources contained therein, and greatly reduce the import volume of oil and gas and external dependence.
[0031] Obviously, the above is only an embodiment of the present invention, and the common knowledge such as the specific structure and characteristics of the scheme is not described in detail. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent.
[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A method for in-situ regulation of volatile matter from associated oil shale oil and gas to pyrolyze oil-rich coal, characterized in that: The process includes the following: An oil-rich coal seam is set on the oil shale layer, and then pyrolysis is carried out at 600~800℃, wherein the oil shale layer is in the lower layer and the oil-rich coal seam is in the upper layer, and the mass ratio of the oil shale layer to the oil-rich coal seam is 1:(1~3).
2. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 1, characterized in that: When pyrolysis is carried out, shale oil and shale gas are separated out from the oil shale layer.
3. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 2, characterized in that: The shale oil components include aromatic compounds, aliphatic compounds, heteroatom compounds, phenolic compounds and impurities.
4. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 3, characterized in that: In terms of mass percentage, the content of aromatic compounds in shale oil is 10%~15%, aliphatic compounds is 20%~25%, heteroatom compounds is 40%~45%, and phenolic compounds is 15%~18%.
5. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 2, characterized in that: The O / C ratio in shale oil is between 0.10 and 0.
16.
6. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 2, characterized in that: The H / C ratio in shale oil is between 0.12 and 0.
15.
7. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 2, characterized in that: The components of the shale gas include H2, CH4, CO2, CO, hydrocarbons and inevitable impurity gases.
8. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 7, characterized in that: In terms of volume percentage, the contents of H2, CH4, CO2, CO and hydrocarbons in shale gas are 35%~45%, 20%~30%, 18%~22%, 8%~10% and 2%~5%, respectively.
9. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 2, characterized in that: The O / C ratio in the shale gas is between 0.6 and 0.
8.
10. The method for in-situ regulation of volatile matter from associated oil shale oil and gas by pyrolysis of oil-rich coal according to claim 2, characterized in that: The H / C ratio in the shale gas is between 1.2 and 1.5.