Process method for improving yield of light phase pitch

Abstract

The invention relates to the field of light-phase pitch separation process optimization, and discloses a process method for improving the yield of light-phase pitch, which comprises the following steps: fully mixing a coal-series maltha raw material and a mixed solvent in a pipeline according to a preset proportion to form a uniform mixed solution; heating the mixed solution to enable the mixed solution to reach a preset temperature interval; enabling the heated mixed solution to enter a settling tank, and standing in the settling tank according to an optimal load for a preset optimal standing time; light-phase asphalt is continuously extracted from a liquid outlet of a light-phase solution tank at the upper part of the settling tank, heavy-phase asphalt is continuously extracted from the bottom of the settling tank through a heavy-phase pump in the extraction process, and anthracene oil is continuously supplemented into the settling tank from the lower part of the settling tank of a heavy-phase asphalt solution in the process of extracting the light-phase asphalt and the heavy-phase asphalt; and the heavy-phase pitch and anthracene oil are blended and then conveyed to a back-end process, and solvent recycling and retreatment are carried out. Therefore, the light-phase asphalt with high yield and low impurity content is stably separated from the coal-series maltha raw material.

Description

Technical Field

[0001] The present invention relates to the field of light phase asphalt separation process optimization, and in particular to a process method for improving the yield of light phase asphalt. Background Art

[0002] Light-phase asphalt refers to the low-density, low-impurity asphalt fraction separated from raw materials during the processing of coal-based soft asphalt through mixed solvent extraction and sedimentation separation techniques. Its key characteristics are as follows: light-phase asphalt is liquid or semi-solid, has a low density, and is typically found in the upper layer of the sedimentation tank. Compared to heavy-phase asphalt, light-phase asphalt has lower viscosity and greater fluidity, and its primary components are soluble components of asphaltenes (such as aromatic hydrocarbons and resins). It is a high-value-added product in coal tar deep processing and can be used to produce high-quality carbon materials, including needle coke and carbon fiber, as well as waterproofing materials. Impurities affecting the purity of light-phase asphalt are primarily quinoline insolubles (QI) and toluene insolubles (TI). Its purity directly impacts the conductivity, mechanical strength, and other properties of subsequent products.

[0003] The current extraction of light phase asphalt has the following problems: 1. The combined process of solvent extraction and centrifugal separation is mainly complex and requires large equipment. The solvent extraction method mainly uses a mixed solvent to extract the active ingredients and then settles them in large equipment. After the sedimentation is completed, separation is directly performed to achieve light phase asphalt extraction; 2. The yield of light phase asphalt is low. Under the current production process, the yield of light phase asphalt is generally 80%-85%; 3. Due to the combined process of solvent extraction and centrifugal separation, the quality control of light-phase asphalt is difficult and the stability of the finished product is relatively poor; 4. The solvents used in the current process are difficult to recycle and reuse. Summary of the Invention

[0004] This summary is intended to briefly introduce concepts that will be described in detail in the detailed description below. This summary is not intended to identify key features or essential features of the claimed technical solution, nor is it intended to limit the scope of the claimed technical solution.

[0005] The present invention proposes a process for improving the yield of light phase asphalt, which is used to solve one or more of the technical problems mentioned in the above background technology part.

[0006] The present invention provides a process for improving the yield of light phase asphalt, which is characterized by comprising the following steps: Step 1: Fully mixing the coal-based soft asphalt raw material and the mixed solvent in a pipeline according to a preset ratio to form a uniform mixed liquid, wherein the mixed solvent is a mixed solvent of dephenolized oil and aviation kerosene, and the aromatic-to-lipid ratio of the mixed solvent is 0.96 to 1.85:1; Step 2: heating the mixed solution to a predetermined temperature. Step 3: The heated mixed liquid enters the sedimentation tank and is allowed to stand in the sedimentation tank according to the optimal load for a preset optimal standing time; Step 4: continuously extracting light phase asphalt from the drain port of the light phase solution tank at the upper part of the settling tank, and continuously extracting heavy phase asphalt containing QI residue from the bottom of the settling tank through a heavy phase pump during the extraction process. During the extraction of light phase asphalt and heavy phase asphalt, anthracene oil is continuously added to the settling tank at the lower part of the settling tank of the heavy phase asphalt solution; Step 5: The heavy phase asphalt and anthracene oil are mixed and transported to the back-end process for solvent recovery and reprocessing.

[0007] Optionally, the mixed solvent is a mixed solvent of dephenolized oil and aviation kerosene.

[0008] Optionally, the dephenolized oil is a mixture of one or more of aromatic hydrocarbons, trimethylbenzene, tetramethylbenzene, indene, naphthalene, and methylnaphthalene.

[0009] Optionally, the aviation kerosene includes different fractions of alkanes, aromatic hydrocarbons and olefinic hydrocarbons, wherein the mass content of aromatic hydrocarbons is less than 20% and the mass content of olefins is less than 3%.

[0010] Optionally, the preset ratio of coal-based soft asphalt raw material to mixed solvent is 0.7:1.

[0011] Optionally, the aromatic ester ratio of dephenolized oil to aviation kerosene in the mixed solvent is 0.96 to 1.26:1.

[0012] Optionally, the aromatic ester ratio of dephenolized oil to aviation kerosene in the mixed solvent is 1±0.04:1.

[0013] Optionally, the preset temperature range is 125°C to 135°C.

[0014] Optionally, the optimal load is 8t / h.

[0015] Optionally, the preset optimal standing time is 5.5 to 5.9 hours.

[0016] Optionally, the heavy phase asphalt and anthracene oil are mixed and transported to the back-end process for solvent recovery and reprocessing, which also includes separating the solvent from the recovered anthracene oil and heavy phase asphalt and returning them to the solvent recycling tank, using a distillation system to recover the anthracene oil, and the remaining residual liquid is evenly mixed with coal tar in an appropriate proportion to form other industrial raw materials.

[0017] Optionally, the optimal aromatic-lipid ratio is mainly determined by the yield of light phase asphalt and the QI impurity ratio under different working conditions in the experiment.

[0018] The present invention has the following beneficial effects: 1. By adjusting the selected solvent and the solvent ratio, a solvent extraction method can be used to directly produce light phase asphalt, specifically by continuously injecting anthracene oil to continuously produce light phase asphalt, while continuously producing light phase asphalt from the drain port of the light phase solution tank at the upper part of the settling tank and continuously producing heavy phase asphalt containing QI residue from the bottom of the settling tank through a heavy phase pump; in the process of producing light phase asphalt and heavy phase asphalt, anthracene oil is continuously added to the settling tank at the lower part of the settling tank of the heavy phase asphalt solution, so that the production valve is prevented from being blocked, and the viscosity of the solution system is reduced by continuously adding anthracene oil, thereby reducing the proportion of impurities in the light phase asphalt, thereby ensuring the continuous production of light phase asphalt and heavy phase asphalt at the lower end while improving the yield of light phase asphalt and reducing QI impurities; 2. By adjusting the solvent selection and solvent ratio for continuous light phase asphalt extraction, the light phase asphalt yield has been stably increased to over 90% over a long period of time; 3. By adjusting the selected solvent and solvent ratio, the light phase asphalt can be directly extracted using the solvent extraction method. The one-time extraction of the light phase asphalt using the solvent extraction method can stably produce high-quality light phase asphalt with QI impurities below 0.1% (QI impurities can be below 0.03% in experiments); 4. The extracted heavy phase asphalt raw materials can be recycled to achieve a comprehensive utilization rate of 100% for pre-treated raw materials. The heavy phase asphalt and anthracene oil are mixed and transported to the back-end process for solvent recovery and reprocessing. The recovered anthracene oil and heavy phase asphalt are separated from the solvent and returned to the solvent reuse tank. The anthracene oil is recovered using a distillation system, and the remaining residual liquid is evenly mixed with coal tar in an appropriate proportion to form other industrial raw materials, which can achieve full utilization of the pre-treated raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other features, advantages, and aspects of the various embodiments of the present invention will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and that the elements are not necessarily drawn to scale.

[0020] Figure 1 The present invention is a process flow chart of a process method for improving the yield of light phase asphalt. DETAILED DESCRIPTION

[0021] The present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0022] It should also be noted that, for ease of description, only the parts related to the invention are shown in the drawings. In the absence of conflict, the embodiments and features of the embodiments of the present invention may be combined with each other.

[0023] It should be noted that the concepts of "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0024] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0025] The names of the messages or information exchanged between multiple devices of the present invention are only used for illustrative purposes and are not used to limit the scope of these messages or information.

[0026] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0027] In one embodiment, Figure 1 As shown, a process for improving the yield of light phase asphalt is characterized by comprising the following steps: S101: fully mixing the coal-based soft asphalt raw material and the mixed solvent in a pipeline according to a preset ratio to form a uniform mixed liquid, wherein the mixed solvent is a mixed solvent of dephenolized oil and aviation kerosene, and the aromatic-to-lipid ratio of the mixed solvent is 0.96 to 1.85:1; In this embodiment, the coal-based soft asphalt raw material is coal-based soft asphalt with a softening point between 35.1°C and 42.3°C and a QI (quinoline insoluble matter) content between 1.92% and 2.86%. The QI impurity particles in the soft asphalt are very small. During movement within the viscous oil system, the outer surface of the particles is continuously coated by the heavier TI-QS (TI-QS is a composite coating composed of toluene-insoluble matter TI and quinoline-soluble matter QS, which hinders the settling of QI particles) and other oil components in the soft asphalt with which it comes into contact. QI itself has no adhesion and will not agglomerate. However, during movement within the viscous oil system, it may agglomerate due to the action of the outer coating, causing the particle size to increase. However, because the outer coating is itself an oil with viscosity and is mixed with the viscous oil system, the density difference between the QI particles and the system cannot overcome the viscosity resistance between the outer coating surface and the system, making it difficult to settle. S102: heating the mixed liquid to a predetermined temperature range; In this embodiment, the commonly used heating method in the field is heating through a heating furnace. The working principle of this step is that the viscosity of the local system is greatly reduced at the moment when the soft asphalt comes into contact with the mixed solvent of the above ratio in an environment with a temperature of 125°C-135°C, which is conducive to overcoming the viscosity resistance of the coal-based soft asphalt raw material and the mixed solvent system and facilitating the sedimentation of the mixed liquid; S103 allows the heated mixed liquid to enter a sedimentation tank and to stand in the sedimentation tank according to an optimal load for a preset optimal standing time; In this embodiment, the principle for determining the optimal standing time in this step is that, under reasonable heavy phase asphalt yield conditions, when the minimum settling time of the mixed liquid is less than the effective residence time provided by the settling device, the light phase asphalt yield and quality can be guaranteed. The greater the time difference between the two overlapping areas, the greater the margin, and the greater the room for increasing the processing load. When the minimum settling time of the mixed liquid is equal to (or close to) the effective residence time provided by the settling device, the light phase asphalt quality is acceptable, but the stability will be affected to a certain extent. At this time, the effective residence time within the settling device corresponding to the critical quality point of the light phase asphalt QI is equal to the minimum settling time of the mixed liquid. When the minimum settling time of the mixed liquid is greater than the effective residence time provided by the settling device, the light phase asphalt quality is unacceptable. S104 continuously extracts light phase asphalt from the drain port of the light phase solution tank at the upper part of the settling tank, and continuously extracts heavy phase asphalt containing QI residue from the bottom of the settling tank through a heavy phase pump during the extraction process. During the extraction of light phase asphalt and heavy phase asphalt, anthracene oil is continuously added to the settling tank at the lower part of the settling tank of the heavy phase asphalt solution; In this embodiment, light phase asphalt is continuously extracted from the discharge port of the light phase solution tank at the upper part of the settling tank, and heavy phase asphalt containing QI residue is continuously extracted from the bottom of the settling tank by a heavy phase pump during the extraction process. In the process of extracting light phase asphalt and heavy phase asphalt, anthracene oil is continuously added to the settling tank at the lower part of the settling tank of the heavy phase asphalt solution. These three steps are carried out simultaneously. The effect of continuously adding anthracene oil to the settling tank at the lower part of the settling tank of the heavy phase asphalt solution is to prevent the extraction valve from being blocked, and the viscosity of the solution system is reduced by continuously adding anthracene oil, thereby reducing the proportion of impurities in the light phase asphalt, thereby ensuring the continuous extraction of light phase asphalt and heavy phase asphalt at the lower end while increasing the yield of light phase asphalt and reducing QI impurities. S105 heavy phase asphalt is mixed with anthracene oil and then transported to the back-end process for solvent recovery and reprocessing.

[0028] In this embodiment, the removal rate of QI impurities is shown in Table 1.

[0029]

[0030] Table 1: QI data of light phase asphalt solution during the experiment of a process for improving light phase asphalt yield; Beneficial effects: This method significantly improves the yield and quality of light-phase asphalt in coal-based soft asphalt by optimizing the mixed solvent ratio and the process of continuously extracting light-phase asphalt, so that the yield of light-phase asphalt can be stably achieved at more than 90% (maximum 91.67%, see Table 2), the quinoline insoluble matter (QI) content is controlled below 0.1% for a long time, and the toluene insoluble matter (TI) content is maintained within a controllable range of 3.3% to 9.5%. By adjusting the selected solvent and solvent ratio, high-quality light-phase asphalt can be directly produced using the solvent extraction method, which significantly enhances the process stability and ensures the continuity of industrial production.

[0031] In one embodiment, the mixed solvent is a mixed solvent of dephenolized oil and aviation kerosene.

[0032] In this embodiment, the dephenolized oil serves primarily to rapidly dissolve the QI particles, stripping and extracting the QI particles and the outer coating that is insoluble in the dephenolized oil. The aviation kerosene component serves to reduce the viscosity of the system, rapidly reducing the volume of the QI particles from which the outer coating has been stripped. Since the QI particles themselves have a higher density than other components in the system, they can rapidly settle in the mixture with reduced viscosity.

[0033] In one embodiment, the preset ratio of the coal-based soft asphalt raw material to the mixed solvent is 0.7:1.

[0034] In this embodiment, as shown in Table 2, 0.7:1 is the optimal mixing ratio of the coal-based soft asphalt raw material and the mixed solvent determined during the test process.

[0035]

[0036] Table 2: Mixed solvent ratios and main quality data at important points during the test period of a process for improving the yield of light phase asphalt; In one embodiment, the aromatic ester ratio of dephenolized oil to aviation kerosene in the mixed solvent is 0.96 to 1.26:1.

[0037] In this embodiment, the 0.96-1.26:1 is the suboptimal aromatic ester ratio of dephenolized oil to aviation kerosene. Within this range, the viscosity of the solution system in the sedimentation device increases but does not exceed the critical amount of the effective residence time of the sedimentation device.

[0038] In one embodiment, the aromatic ester ratio of dephenolized oil to aviation kerosene in the mixed solvent is 1±0.04:1.

[0039] In this embodiment, the aromatic-lipid ratio of the dephenolized oil to aviation kerosene is 1±0.04:1, which is the optimal aromatic-lipid ratio determined by experiments. The process for determining the optimal aromatic-lipid ratio is shown in Table 2. The principle is that the optimal mixed solvent ratio for settling QI separation in each complex mixed component system is not a single point, but a range. Under the conditions that the settling equipment, temperature environment, load, and solvent ratio remain unchanged, and the original mixed solvent ratio itself is within the optimal applicable range, as the aromatic-lipid ratio gradually increases, the dephenolized oil's ability to dissolve the TI-QS components coated on the outer surface of QI particles is simultaneously enhanced. At the same time, the reduction in kerosene content simultaneously weakens the kerosene's ability to reduce the system viscosity. Under these combined effects, the system viscosity increases simultaneously, and the dissolving power gradually increases within the optimal applicable range, which strengthens its ability to strip the TI-QS components coated on the outer surface of QI particles and is beneficial to the separation efficiency of QI. As the viscosity increases further, the required settling time is also extended. Because it is still within the applicable range and does not exceed the critical amount of the effective retention time of the settling equipment, the quality and yield of the light phase asphalt are not affected, but the ratio is no longer optimal.

[0040] When the aromatic-lipid ratio continues to increase until it leaves the applicable range, the actual reduction in the amount of kerosene components in the mixed solvent makes the viscosity of the system itself insufficient to support the effective sedimentation of QI particles; the excess dephenolized oil not only satisfies the need to strip the TI-QS components wrapped around the outside of the QI particles, but also exhibits excess extraction capacity, extracting a portion of the TI-QS components that already exist in the soft asphalt system into the dephenolized oil solvent layer. The extraction of the TI-QS components in the soft asphalt system on its contact surface by the excessive locally concentrated dephenolized oil is marginal, layered homogeneous extraction, and a sedimentation oil film will be formed in the dephenolized oil layer. The density of the TI-QS component is higher than that of the dephenolized oil. During the rapid sedimentation process, the QI impurity particles therein regenerate the oil film. As the dephenolized oil gradually disperses in the soft asphalt system, the QI particles cannot be stripped after regenerating the oil film, resulting in an increase in particle size and an increase in sedimentation resistance, which in turn prolongs the sedimentation time. At the same time, whether the QI particles re-wrapped with TI-QS components can settle in the new system is related to the thickness of its outer layer and the viscosity difference between the surface and the system. When the density difference cannot overcome the surface tension, it will require an infinitely long theoretical sedimentation time, which is reflected in the decrease in yield and quality until it cannot settle.

[0041] In one embodiment, the heavy phase asphalt and anthracene oil are mixed and transported to the back-end process for solvent recovery and reprocessing, which also includes separating the solvent from the recovered anthracene oil and heavy phase asphalt and returning them to the solvent recycling tank, using a distillation system to recover the anthracene oil, and the remaining residual liquid is evenly mixed with coal tar in an appropriate proportion to form other industrial raw materials.

[0042] In order to further solve the technical problem described in the background technology section, namely, "the solvents used in the current process are difficult to recycle and reuse", in some embodiments of the present invention, the recovered anthracene oil and heavy phase asphalt can be separated from the solvent and returned to the solvent recycling tank, and the anthracene oil can be recovered using a distillation system. The remaining residual liquid containing unseparated colloids and a small amount of QI can be evenly mixed with coal tar in an appropriate proportion and used as a high-quality raw material for the production of modified asphalt in a tar device, which can achieve a comprehensive utilization rate of 100% for the pretreated raw materials.

[0043] In one embodiment, the optimal aromatic-to-lipid ratio is mainly determined by the yield of light phase asphalt and the QI impurity ratio under different working conditions in the experiment.

[0044] Some specific embodiments are provided below to illustrate the present invention: Example 1: Soft asphalt raw material was added, and the initial operating conditions were a mixed solvent with an aromatic-resin ratio of 0.98 to 1.0, a solvent ratio of 0.8, and a soft asphalt feed rate of 8 t / h. The continuous production volume of the heavy phase asphalt solution was adjusted to adjust the QI of the light phase asphalt solution. At the same time, anthracene oil was continuously added after the production valve of the heavy phase asphalt solution to prevent blockage. In this embodiment, the QI of the light phase asphalt was 0.04%, and the light phase asphalt yield was 78.59%.

[0045] Example 2: Soft asphalt raw material was added to test the maximum possible yield of light phase asphalt under the conditions of a solvent ratio of 0.7 and an aromatic resin ratio of 1.0. The soft asphalt feed rate was 8 t / h as the initial operating condition. The continuous production of heavy phase asphalt solution was adjusted to adjust the QI of the light phase asphalt solution. At the same time, anthracene oil was continuously added after the production valve of the heavy phase asphalt solution to prevent blockage. On the premise of maintaining the stable and qualified QI of the light phase asphalt solution, the production ratio of heavy phase asphalt was gradually reduced to increase the yield of light phase asphalt. The daily production of heavy phase asphalt was gradually reduced from 22.52% of soft asphalt to 7.29% of soft asphalt. During this period, no abnormalities were found in the QI quality inspection data of light phase asphalt. The yield of light phase asphalt was gradually increased from 77.30% to 90.16% and then stabilized.

[0046] Example 3: Soft asphalt raw material was added, with a solvent ratio of 0.7 and a soft asphalt feed rate of 8 t / h as the initial operating conditions. The continuous extraction rate of the heavy phase asphalt solution was adjusted to adjust the QI of the light phase asphalt solution. At the same time, anthracene oil was continuously added after the extraction valve of the heavy phase asphalt solution to prevent blockage. The aromatic-resin ratio was continuously increased to 1.26. During this period, a flow sample of the asphalt solution was taken before the inlet of the sedimentation tank for observation. The appearance speed of the sand-like fine particles that were quickly separated from the solution under the aromatic-resin ratio of 1.0 gradually slowed down with the increase of the aromatic-resin ratio until they disappeared and were replaced by visible coarse particles. The theoretical time required for sedimentation was extended. During this period, the quality of the light phase asphalt solution continued to be qualified. The aromatic-resin ratio was increased from 1.26 to 1.6 to start the QI of the light phase asphalt solution. % began to show a trend towards unqualified (0.03%), with the highest peak value of 0.14% on the day; based on the sedimentation tank structure model, the effective sedimentation time in the sedimentation tank on September 17 was calculated to be 5.3h. Based on this, it can be inferred that the upper limit critical value of the applicable range of the aromatic-resin ratio under the conditions of a solvent ratio of 0.7 and a processing capacity load of 8t / h is close to 1.26. When this critical value is exceeded, the effective retention time that the sedimentation tank can provide will be lower than the actual sedimentation time required for QI separation of the mixed liquid; while maintaining the solvent ratio at 0.7, the aromatic-resin ratio was continued to be increased from 1.6 to 1.81. The current effective retention time was calculated as 5.3h, and the QI% of the light phase asphalt solution increased significantly by 1.02%, and then remained around 0.7% thereafter. According to the data analysis, the amount of kerosene added in this state is seriously insufficient, and it cannot meet the requirements either in reducing the viscosity of the system or assisting in the stripping of the coating layer. The viscosity increases, and it is not enough to achieve effective separation within the existing effective residence time; the aromatic-resin ratio is rapidly increased from the original 2.04 to 2.58, the solvent ratio is increased from 0.7 to 1.0, and the QI of the light phase asphalt solution is 0.96%. During this period, the light phase asphalt produced solution continued to be unqualified; it is calculated that the effective residence time of the mixed liquid in the sedimentation tank is 4.5h; the aromatic-resin ratio is reduced from 2.52 to 2.4, and the volume ratio remains unchanged at 1.0; the load is reduced to 6t / h, and the QI of the light phase asphalt is unqualified during this period.

[0047] This embodiment mainly observes by taking asphalt solution flow samples before the sedimentation tank inlet. When the QI particles in the solution appear as fine oil sand-like particles, the sedimentation rate is fast and the instantaneous separation is complete. This is the optimal range of aromatic-to-lipid ratio. On this basis, by further reducing the recovery ratio of the heavy phase asphalt solution, a higher light phase asphalt yield can be explored, and the actual quality turning point can be found. The QI particles appear to be wrapped by external oil, the sedimentation rate is significantly slowed, and they are suspended in the system. There is no sign of instantaneous separation. The quality of the light phase asphalt solution continues to be qualified, which is the second best aromatic-to-lipid ratio. When the QI of the light phase asphalt solution begins to show a trend towards unqualified, it is within the usable aromatic-to-lipid ratio range. When the QI of the light phase asphalt solution is unqualified, the aromatic-to-lipid ratio is unusable.

[0048]

[0049]

[0050] Table 3: Yields of the main products obtained in Examples 1 to 3 of a process for improving the yield of light phase asphalt; Table 3 shows the yields of the main products prepared in Examples 1 to 3. As can be seen from the yields in the figure, the solvent ratio is 0.7, the aromatic lipid ratio is 1±0.04, and the load is 8 t / h. This condition is the optimal applicable range of the mixed solvent ratio. The solvent ratio is 0.7, the aromatic lipid ratio is 1.19-1.26, and the load is 8 t / h. This condition is close to the optimal applicable range. During this period, the regulation of the aromatic lipid ratio of the mixed solvent did not deviate from the applicable range.

[0051] The above descriptions are merely some preferred embodiments of the present invention and illustrate the underlying technical principles. Those skilled in the art should understand that the scope of the present invention is not limited to technical solutions formed by specific combinations of the aforementioned technical features. It also encompasses other technical solutions formed by any combination of the aforementioned technical features or their equivalents, without departing from the aforementioned inventive concept. For example, a technical solution formed by replacing the aforementioned features with (but not limited to) technical features with similar functions disclosed in this invention.

Claims

1. A process for improving the yield of light phase asphalt, characterized in that: The following steps are involved: Step 1: Fully mixing the coal-based soft asphalt raw material and the mixed solvent in a pipeline according to a preset ratio to form a uniform mixed liquid, wherein the mixed solvent is a mixed solvent of dephenolized oil and aviation kerosene, and the aromatic-to-lipid ratio of the mixed solvent is 0.96 to 1.85:1; Step 2: heating the mixed solution to a predetermined temperature. Step 3: The heated mixed liquid enters the sedimentation tank and is allowed to stand in the sedimentation tank according to the optimal load for a preset optimal standing time; Step 4: continuously extracting light phase asphalt from the drain port of the light phase solution tank at the upper part of the settling tank, and continuously extracting heavy phase asphalt containing QI residue from the bottom of the settling tank through a heavy phase pump during the extraction process. During the extraction of light phase asphalt and heavy phase asphalt, anthracene oil is continuously added to the settling tank at the lower part of the settling tank of the heavy phase asphalt solution; Step 5: The heavy phase asphalt and anthracene oil are mixed and transported to the back-end process for solvent recovery and reprocessing.

2. A process for improving the yield of light phase asphalt according to claim 1, characterized in that: The dephenolized oil is one or a mixture of more than one of aromatic hydrocarbons, trimethylbenzene, tetramethylbenzene, indene, naphthalene and methylnaphthalene.

3. A process for improving the yield of light phase asphalt according to claim 1, characterized in that: The aviation kerosene comprises alkanes, aromatic hydrocarbons and olefin hydrocarbons of different fractions, wherein the mass content of aromatic hydrocarbons is below 20% and the mass content of olefins is below 3%.

4. A process for improving the yield of light phase asphalt according to claim 1, characterized in that: The preset ratio of coal-based soft asphalt raw material to mixed solvent is 0.7:

1.

5. A process for improving the yield of light phase asphalt according to claim 1, characterized in that: The aromatic ester ratio of the dephenolized oil to the aviation kerosene in the mixed solvent is 0.96-1.26:

1.

6. A process for increasing the yield of light phase asphalt according to any one of claim 1, characterized in that: The aromatic ester ratio of the dephenolized oil to the aviation kerosene in the mixed solvent is 1±0.04:

1.

7. A process for improving the yield of light phase asphalt according to claim 1, characterized in that: The preset temperature range is 125°C to 135°C.

8. A process for improving the yield of light phase asphalt according to claim 1, characterized in that: The optimal load is 8t / h.

9. A process for improving the yield of light phase asphalt according to claim 1, characterized in that: The preset optimal standing time is 5.5 to 5.9 hours.

10. A process for increasing the yield of light phase asphalt according to any one of claims 1 to 9, characterized in that: After the heavy phase asphalt and anthracene oil are mixed, they are transported to the back-end process for solvent recovery and reprocessing, which also includes separating the solvent from the recovered anthracene oil and heavy phase asphalt and returning them to the solvent reuse tank, using a distillation system to recover the anthracene oil, and evenly mixing the remaining residual liquid with coal tar in an appropriate proportion to produce other industrial raw materials.

11. A process for increasing the yield of light phase asphalt according to any one of claims 1, 2, 3, 5 and 6, characterized in that: The optimal aromatic-to-lipid ratio is mainly determined by the yield of light phase asphalt and the QI impurity ratio under different working conditions in the experiment.

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