A production method and a production system of impregnated bitumen

Abstract

The application discloses a production method and a production system of impregnated pitch, and the production method comprises the following steps: (1) separating raw oil to obtain light fraction, middle fraction and heavy fraction; (2) reacting the light fraction in a first reaction unit to obtain a first stream; (3) reacting the heavy fraction in a second reaction unit to obtain a second stream; (4) mixing the middle fraction, the first stream and the second stream into a third reaction unit to react, and obtaining light components and impregnated pitch after the reaction. The production system comprises a first separation unit, a second separation unit, a first reaction unit, a second reaction unit and a third reaction unit. The production method has the advantages of high product yield and low quinoline insoluble content of the impregnated pitch, and solves the problems of complex production process and low product yield in the prior art.

Description

Technical Field

[0001] This invention belongs to the field of petrochemical technology and relates to a method for producing asphalt, particularly a method for producing impregnated asphalt. Background Technology

[0002] Impregnating bitumen is a common densifying and reinforcing agent in carbon material production, mainly used in the impregnation process of high-power and ultra-high-power graphite electrodes and high-tech carbon products such as aerospace and military special graphite. The impregnating bitumen is required to have good rheological and penetrating properties to smoothly penetrate into the material pores, while also possessing a good coking value to improve the impregnation uniformity and weight gain of the carbon material. The intrinsic properties of bitumen are low quinoline insoluble matter, low softening point, and high coking value. Impregnating bitumen can be prepared using physical and chemical methods. Physical methods utilize filtration, centrifugation, sedimentation, flocculation, distillation, and extraction to directly remove quinoline insoluble matter from the raw bitumen, resulting in low-quinoline-insoluble impregnating bitumen. Chemical methods utilize high-temperature polymerization of aromatic components, generally using anthracene oil and other materials free of quinoline insoluble matter as raw materials. By controlling process conditions such as polymerization temperature, pressure, and time, low-quinoline-insoluble impregnating bitumen is obtained.

[0003] The quality of impregnating bitumen directly affects the production cost and material properties of high-performance carbon materials. However, due to raw material and technical reasons, most industries in China currently use ordinary medium-temperature bitumen instead of impregnating bitumen, resulting in unstable product quality, high energy consumption, and difficulty in meeting high-level application requirements. This seriously hinders the product upgrading and replacement in industries such as graphite, metallurgy, machinery, nuclear, and military. Therefore, there is a need to provide a method for large-scale production of high-quality impregnating bitumen.

[0004] Chinese patent CN105271168A discloses a method for the continuous preparation of mesophase carbon microspheres and the co-production of impregnating agent pitch and coated pitch. The method uses medium-temperature coal tar pitch as raw material, adds a stabilizer, mixes it, first heats it at a low temperature, then performs a short-term high-temperature polymerization reaction, cools it down, mixes it with an extractant for extraction, centrifuges it, and then feeds it into a reactor for a modification reaction. This process requires both stabilizers and extractants, involves an extractant recovery process, is complex, and poses potential environmental pollution risks.

[0005] Chinese patent CN110540855 A discloses a petroleum-based impregnated bitumen and its preparation method. The method involves solvent deasphalting of catalytic cracking slurry, mixing purified reduced-triple-line furfural extract oil or reduced-quadruple-line furfural extract oil with the purified catalytic cracking slurry in a certain proportion, and then carrying out a thermal polymerization reaction. The resulting product is distilled to remove light components, thus obtaining the impregnated bitumen. This process requires the use of solvents for deasphalting experiments, involves solvent use and recovery processes, is complex, and poses potential environmental pollution risks.

[0006] Chinese Patent CN106701134 A discloses a method for producing petroleum-based impregnated bitumen. The method uses heavy oils such as catalytic cracking slurry and ethylene cracking tar as raw materials, and then processes them through purification, blending, thermal polymerization, refining, and molding to obtain high-quality petroleum-impregnated bitumen products. The production process involves multiple solvents, which poses potential environmental pollution risks. Furthermore, the production process is complex and difficult to scale up. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the main objective of this invention is to provide a method and system for producing impregnated bitumen. The impregnated bitumen produced by this method has the advantages of high product yield and low quinoline insoluble content, and it is easy to achieve large-scale production of high-quality impregnated bitumen. This solves the problems of complex production processes, low product yield, and potential environmental pollution risks in existing technologies.

[0008] The technical solution of this invention includes the following aspects:

[0009] The first aspect of this invention provides a method for producing impregnated bitumen, the method comprising the following steps:

[0010] (1) The feedstock enters the first separation unit and is separated to obtain light fraction, middle fraction and heavy fraction;

[0011] (2) The light fraction obtained in step (1) enters the first reaction unit and the first feed stream is obtained after the reaction;

[0012] (3) The heavy fraction obtained in step (1) enters the second reaction unit and a second feed stream is obtained after the reaction;

[0013] (4) The intermediate fraction obtained in step (1), the first feed stream obtained in step (2), and the second feed stream obtained in step (3) are mixed and fed into the third reaction unit for reaction. After the reaction, light components and impregnated asphalt are obtained.

[0014] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the feedstock oil can be petroleum-based feedstock and / or coal-based feedstock. The petroleum-based feedstock can be one or a mixture of two or more of ethylene tar, thermal cracking residue oil, wax oil, catalytic cracking slurry oil, etc., and the coal-based feedstock can be one or a mixture of two or more of low-temperature coal tar, medium-temperature coal tar, and high-temperature coal tar.

[0015] Furthermore, in the above-mentioned method for producing impregnated asphalt, as a preferred embodiment, the raw material oil is first purified. The purified raw material oil has an ash content of no more than 0.2 wt%, preferably no more than 0.1 wt%, more preferably no more than 0.05 wt%; a sulfur content of no more than 1 wt%, preferably no more than 0.5 wt%; and an asphaltene content of no more than 5.0 wt%, preferably no more than 2.0 wt%. The purification treatment can employ any one or more of the existing purification methods in the art, specifically solvent extraction, positive pressure filtration, centrifugal separation, etc.

[0016] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the cutting temperature of the light fraction and the middle fraction in step (1) is 300-400°C, preferably 340-380°C.

[0017] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the cutting temperature of the middle fraction and the heavy fraction in step (1) is 430-530°C, preferably 460-500°C.

[0018] Furthermore, in the above-mentioned method for producing impregnated asphalt, as a preferred embodiment, the reaction conditions of the first reaction unit in step (2) are: temperature of 200-400℃, preferably 320-380℃, reaction pressure of 1.0-10.0MPa, preferably 4.0-8.0MPa, and material residence time of 1-10h, preferably 5-9h.

[0019] Furthermore, in the above-mentioned method for producing impregnated asphalt, as a preferred embodiment, when the light fraction obtained in step (1) enters the first reaction unit for reaction in step (2), an auxiliary agent is introduced at the same time. The auxiliary agent can be selected from one or more of paraformaldehyde, p-toluenesulfonic acid, and diethylenetriamine. The weight ratio of the auxiliary agent to the light fraction is 5% to 15%, preferably 6% to 10%.

[0020] Furthermore, in the above-mentioned method for producing impregnated asphalt, as a preferred embodiment, the reaction conditions of the second reaction unit in step (3) are as follows: the reaction temperature is 380-430℃, preferably 390-420℃, the reaction pressure is 1.0-5.0MPa, preferably 2.0-4.0MPa, and the material residence time is 5-20h, preferably 10-15h.

[0021] Furthermore, in the above-mentioned method for producing impregnated asphalt, as a preferred embodiment, the reaction conditions of the third reaction unit in step (4) are as follows: the reaction temperature is 350-450℃, preferably 380-420℃, the reaction pressure is 0.5-8.0MPa, preferably 3.0-6.0MPa, and the material residence time is 1-18h, preferably 6-15h.

[0022] Furthermore, in the above-mentioned method for producing impregnated asphalt, as a preferred embodiment, the light component obtained in step (4) is further separated to obtain a third stream and gas, wherein the third stream is returned to the first reaction unit for processing together with the light fraction. The separation can be carried out using a flash distillation tower, with an operating temperature of 300-400°C, preferably 350-380°C.

[0023] Furthermore, in the above-mentioned production method of impregnated asphalt, the softening point of the obtained impregnated asphalt is not lower than 80℃, the quinoline insoluble content is not higher than 2wt%, the toluene insoluble content is not lower than 8wt%, the coking value is not lower than 47%, and the ash content is less than 0.1wt%.

[0024] A second aspect of the present invention provides a production system for impregnated bitumen, the production system comprising:

[0025] The first separation unit is used to receive and separate the feed oil, and obtain light fraction, middle fraction and heavy fraction after separation;

[0026] The first reaction unit is used to receive light fractions and optional additives from the first separation unit, and the reaction yields the first feed stream;

[0027] The second reaction unit is used to receive the heavy fraction from the first separation unit and react it to obtain the second feed stream;

[0028] The third reaction unit is used to receive the intermediate fraction from the first separation unit, the first feed stream from the first reaction unit, and the second feed stream from the second reaction unit, and to obtain light components and impregnated bitumen after the reaction.

[0029] Furthermore, in the above-mentioned impregnated bitumen production system, as a preferred embodiment, the impregnated bitumen production system further includes a second separation unit, which is used to receive light components from the third reaction unit, and separate them to obtain a third material stream and gas; the third material stream obtained after separation by the second separation unit enters the first reaction unit through a pipeline.

[0030] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the first separation unit includes at least one device capable of cutting materials according to the distillation range, specifically a fractionating tower, and particularly preferably a vacuum distillation tower.

[0031] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the first reaction unit can be a batch reactor or a tank reactor.

[0032] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the second reaction unit can be at least one of a tower reactor, a tank reactor, or a batch reactor.

[0033] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the third reaction unit may be at least one of a tower reactor, a tank reactor, or a batch reactor.

[0034] Furthermore, in the above-mentioned method for producing impregnated bitumen, as a preferred embodiment, the second separation unit includes at least one device capable of cutting materials according to the distillation range, specifically at least one of a vacuum distillation tower and a flash distillation tower.

[0035] Furthermore, in the above-mentioned production system for impregnated bitumen, as a preferred embodiment, the production system includes a purification device, which can be at least one of a filtration device and a centrifuge device.

[0036] Compared with the prior art, the production method and system for impregnated bitumen provided by the present invention have the following beneficial effects:

[0037] 1. The impregnated bitumen production method provided by this invention involves separating the feedstock oil into three different fractions, then processing the light and heavy fractions separately, and finally mixing the middle fraction with the processed light and heavy fractions to produce impregnated bitumen. An additive is introduced in the first reaction unit, and the separated third stream is recycled back to the first reaction unit. Through the combined effect of these methods, the toluene-insoluble and quinoline-insoluble content of the impregnated bitumen product is optimally controlled. The impregnated bitumen production method provided by this invention can achieve maximum production of impregnated bitumen and significantly improves the effective utilization rate of raw materials.

[0038] 2. The impregnated bitumen production method provided by this invention does not introduce highly corrosive liquid or gas catalysts, nor does it use extractants, which is conducive to large-scale industrialization and promotion. Moreover, the resulting impregnated bitumen product has a high yield, low quinoline insoluble content, high toluene insoluble content, and high product quality. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the production method of impregnated bitumen provided by the present invention.

[0040] Wherein: 1-Federal feedstock, 2-First separation unit, 3-Light fraction, 4-Middle fraction, 5-Heavy fraction, 6-First reaction unit, 7-Second reaction unit, 8-First feed stream, 9-Second feed stream, 10-Third reaction unit, 11-Light component, 12-Impregnated bitumen, 13-Second separation unit, 14-Gas, 15-Third feed stream, 16-Auxiliary agent. Detailed Implementation

[0041] The specific embodiments of the present invention will be described in detail below. However, it should be noted that the scope of protection of the present invention is not limited to these specific embodiments, but is determined by the claims in the appendix.

[0042] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0043] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0044] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0045] In the context of this specification, for ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” “above,” “upper,” etc., may be used to describe the relationship of one element or feature to another element or feature in the accompanying drawings. It should be understood that spatial relative terms are intended to encompass different orientations of an object in use or operation, other than those depicted in the figures. For example, if an object in the figure is flipped, an element described as “below” or “under” another element or feature would be oriented “above” said element or feature. Thus, the exemplary term “below” can encompass both the downward and upward orientations. An object may also have other orientations (e.g., rotated 90 degrees or other orientations), and the spatial relative terms used herein should be interpreted accordingly.

[0046] In the context of this specification, the terms "first," "second," etc., are used to distinguish two different elements or parts, and are not used to define a specific position or relative relationship. In other words, in some embodiments, the terms "first," "second," etc., can also be used interchangeably.

[0047] In the context of this specification, all numeric values ​​of parameters (e.g., quantities or conditions) should be understood to be modified by the term “about” in all cases, regardless of whether “about” actually appears before the numeric value.

[0048] In the context of this specification, the ash content of the oil is determined by method GB / T 508, and the sulfur content is determined by method SH / T0689.

[0049] In the context of this specification, the ash content of impregnated bitumen is determined by method GB / T 1429, and the sulfur content is determined by method GB / T 24526. The coking value is determined by method GB / T 8727-2008.

[0050] Unless otherwise specified, all percentages, parts, ratios, etc. mentioned in this instruction manual are based on weight, and the pressure is gauge pressure.

[0051] In the context of this specification, any two or more embodiments of the present invention can be arbitrarily combined, and the resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0052] like Figure 1 The specific process flow of the impregnated bitumen production method provided by the present invention is as follows: Raw material oil 1 enters the first separation unit 2, and after separation, light fraction 3, middle fraction 4 and heavy fraction 5 are obtained; wherein the light fraction 3 obtained from the first separation unit 2 and optional additive 16 enter the first reaction unit 6, and after reaction, a first feed stream 8 is obtained; the heavy fraction 5 obtained from the first separation unit 2 enters the second reaction unit 7, and after reaction, a second feed stream 9 is obtained; the middle fraction 4 obtained from the first separation unit, the first feed stream 8 obtained from the first reaction unit and the second feed stream 9 obtained from the second reaction unit enter the third reaction unit 10 for reaction, and after reaction, light component 11 and impregnated bitumen 12 are obtained; the light component 11 enters the second separation unit 13 for separation, and after separation, gas 14 and a third feed stream 15 are obtained, and the third feed stream 15 is returned to the first reaction unit 6.

[0053] Example 1

[0054] Example 1 uses the raw materials listed in Table 1. Figure 1 The process flow is as follows: in the first separation unit, the cutoff point between the light and middle fractions is 340℃, and the cutoff point between the middle and heavy fractions is 460℃. The reaction conditions in the first reaction unit are: reaction temperature 320℃, pressure 6 MPa, residence time 6 h, without the use of any additives. The reaction conditions in the second reaction unit are: reaction temperature 430℃, pressure 1 MPa, residence time 11 h. The reaction conditions in the third reaction unit are: reaction temperature 350℃, pressure 4 MPa, residence time 15 h. The operating condition of the second separation unit is 350℃. The third feed stream is not returned to the first reaction unit. The reaction results are shown in Table 2.

[0055] Example 2

[0056] Example 2 uses the raw materials listed in Table 1. Figure 1 The process flow is as follows: in the first separation unit, the cutoff point between the light and middle fractions is 300℃, and the cutoff point between the middle and heavy fractions is 510℃. The reaction conditions in the first reaction unit are: reaction temperature 230℃, pressure 8 MPa, residence time 9 h, using paraformaldehyde as an additive. The reaction conditions in the second reaction unit are: reaction temperature 390℃, pressure 3 MPa, residence time 15 h. The reaction conditions in the third reaction unit are: reaction temperature 450℃, pressure 3 MPa, residence time 10 h. The operating condition of the second separation unit is: temperature 380℃. The third feed stream is returned to the first reaction unit. The reaction results are shown in Table 2.

[0057] Example 3

[0058] Example 3 uses the raw materials listed in Table 1. Figure 1 The process flow is as follows: in the first separation unit, the cutoff point between the light and middle fractions is 380℃, and the cutoff point between the middle and heavy fractions is 430℃. The reaction conditions in the first reaction unit are: reaction temperature 400℃, pressure 2 MPa, residence time 1 h, using p-toluenesulfonic acid as an auxiliary agent. The reaction conditions in the second reaction unit are: reaction temperature 415℃, pressure 2 MPa, residence time 5 h. The reaction conditions in the third reaction unit are: reaction temperature 385℃, pressure 0.5 MPa, residence time 18 h. The operating conditions in the second separation unit are: temperature 360℃. The third feed stream is returned to the first reaction unit. The reaction results are shown in Table 2.

[0059] Example 4

[0060] Example 2 uses the raw materials listed in Table 1. Figure 1 The process flow is as follows: in the first separation unit, the cutoff point between the light and middle fractions is 400℃, and the cutoff point between the middle and heavy fractions is 470℃. The reaction conditions in the first reaction unit are: reaction temperature 380℃, pressure 10 MPa, residence time 5 h, using diethylenetriamine as an adjuvant. The reaction conditions in the second reaction unit are: reaction temperature 385℃, pressure 5 MPa, residence time 20 h. The reaction conditions in the third reaction unit are: reaction temperature 365℃, pressure 6 MPa, residence time 4 h. The operating condition of the second separation unit is: temperature 370℃. The third feed stream is returned to the first reaction unit. The reaction results are shown in Table 2.

[0061] Comparative Example 1

[0062] The reaction was basically the same as in Example 1, except that the light fraction did not enter the first reaction unit, the heavy fraction did not enter the second reaction unit, and only the middle fraction entered the third reaction unit for reaction. The reaction results are shown in Table 2.

[0063] Table 1 Analysis of Raw Material Properties

[0064]

[0065] Table 2 Reaction Results

[0066]

Claims

1. A method for producing impregnated bitumen, the method comprising the following steps: (1) The feed oil enters the first separation unit and is separated to obtain light fraction, middle fraction and heavy fraction; the cut temperature of light fraction and middle fraction is 300-400℃, and the cut temperature of middle fraction and heavy fraction is 430-530℃. (2) The light fraction obtained in step (1) enters the first reaction unit and the first feed stream is obtained after the reaction; the reaction conditions of the first reaction unit are: temperature of 200~400℃ and reaction pressure of 1.0~10.0MPa; (3) The heavy fraction obtained in step (1) enters the second reaction unit and a second feed stream is obtained after the reaction; the reaction conditions of the second reaction unit are: the reaction temperature is 380~430℃ and the reaction pressure is 1.0~5.0MPa; (4) The intermediate fraction obtained in step (1), the first feed stream obtained in step (2), and the second feed stream obtained in step (3) are mixed and fed into the third reaction unit for reaction. After the reaction, light components and impregnated bitumen are obtained. The light components are further separated to obtain the third feed stream and gas. The third feed stream is returned to the first reaction unit for processing together with the light fraction.

2. The method for producing impregnated bitumen according to claim 1, characterized in that: The feedstock is a petroleum-based feedstock and / or a coal-based feedstock, wherein the petroleum-based feedstock is one or a mixture of two or more of ethylene tar, thermal cracking residue oil, wax oil, and catalytic cracking slurry, and the coal-based feedstock is one or a mixture of two or more of low-temperature coal tar, medium-temperature coal tar, and high-temperature coal tar.

3. The method for producing impregnated bitumen according to claim 1, characterized in that: The crude oil is first purified. The purified crude oil has an ash content of no more than 0.2 wt%, a sulfur content of no more than 1 wt%, and an asphaltene content of no more than 5.0 wt%.

4. The method for producing impregnated bitumen according to claim 1, characterized in that: The crude oil is first purified. The purified crude oil has an ash content of no more than 0.1 wt%, a sulfur content of no more than 0.5 wt%, and an asphaltene content of no more than 2.0 wt%.

5. The method for producing impregnated bitumen according to claim 1, characterized in that: The crude oil is first purified, and the ash content of the purified crude oil is no more than 0.05 wt%.

6. The method for producing impregnated bitumen according to claim 1, characterized in that: The cutting temperature of the light and middle fractions in step (1) is 340-380℃.

7. The method for producing impregnated bitumen according to claim 1, characterized in that: The cutting temperature of the middle distillate and heavy distillate in step (1) is 460-500℃.

8. The method for producing impregnated bitumen according to claim 1, characterized in that: The reaction conditions of the first reaction unit in step (2) are: temperature of 320-380℃, reaction pressure of 4.0-8.0MPa, and material residence time of 1-10h.

9. The method for producing impregnated bitumen according to claim 8, characterized in that: The material residence time is 5 to 9 hours.

10. The method for producing impregnated bitumen according to claim 1, characterized in that: When the light fraction obtained in step (1) enters the first reaction unit for reaction as described in step (2), an auxiliary agent is introduced at the same time. The auxiliary agent is selected from one or more of paraformaldehyde, p-toluenesulfonic acid, and diethylenetriamine. The weight ratio of the auxiliary agent to the light fraction is 5% to 15%.

11. The method for producing impregnated bitumen according to claim 1, characterized in that: When the light fraction obtained in step (1) enters the first reaction unit for reaction as described in step (2), an auxiliary agent is introduced at the same time. The auxiliary agent is selected from one or more of paraformaldehyde, p-toluenesulfonic acid, and diethylenetriamine. The weight ratio of the auxiliary agent to the light fraction is 6% to 10%.

12. The method for producing impregnated bitumen according to claim 1, characterized in that: The reaction conditions for the second reaction unit in step (3) are: reaction temperature of 390-420℃, reaction pressure of 2.0-4.0MPa, and material residence time of 5-20h.

13. The method for producing impregnated bitumen according to claim 12, characterized in that: The material residence time is 10-15 hours.

14. The method for producing impregnated bitumen according to claim 1, characterized in that: The reaction conditions for the third reaction unit in step (4) are: reaction temperature of 350-450℃, reaction pressure of 0.5-8.0MPa, and material residence time of 1-18h.

15. The method for producing impregnated bitumen according to claim 1, characterized in that: The reaction conditions for the third reaction unit in step (4) are: reaction temperature of 380-420℃, reaction pressure of 3.0-6.0MPa, and material residence time of 6-15h.

16. A production system for implementing the method for producing impregnated bitumen according to any one of claims 1-15, the production system comprising: The first separation unit is used to receive and separate the feed oil, and obtain light fraction, middle fraction and heavy fraction after separation; The first reaction unit is used to receive light fractions and optional additives from the first separation unit, and the reaction yields the first feed stream; The second reaction unit is used to receive the heavy fraction from the first separation unit and react it to obtain the second feed stream; The third reaction unit is used to receive the intermediate fraction from the first separation unit, the first feed stream from the first reaction unit, and the second feed stream from the second reaction unit, and after the reaction, light components and impregnated bitumen are obtained. The second separation unit is used to receive the light components from the third reaction unit, and after separation, obtains a third feed stream and gas; the third feed stream enters the first reaction unit through a pipeline.

17. The production system for impregnated bitumen according to claim 16, characterized in that: The production system for impregnated bitumen includes a purification device, which is at least one of a filtration device and a centrifuge device.

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