Process for refining anthracene oil from coal tar

Abstract

The invention belongs to an anthracene oil refining technology, and particularly relates to a process for refining anthracene oil from coal tar. An extraction agent A is injected in a liquid form and is mixed with anthracene oil fractions in a first refining chamber, the extraction agent A and the anthracene oil fractions enter a second refining chamber in a mixed liquid form through a filter screen plate, cooling water is continuously introduced into the second refining chamber through a circulating water jacket to complete crystallization, and an extraction phase is returned to the first refining chamber through the filter screen plate; the method comprises the following steps: introducing an extraction agent A into a first refining chamber, introducing an extraction agent B into a second refining chamber to carry out secondary extraction on an extraction residual phase, after secondary extraction, introducing a secondary extraction phase into the first refining chamber through a filter screen plate to obtain a mixed phase, and carrying out fraction treatment in a separation tower to obtain the extraction agent A, the extraction agent B, phenanthrene-containing oil and carbazole-containing oil, so that the separation efficiency can be greatly improved; the one-tower double-separation operation is completed in the refining tower, so that the process steps are greatly simplified, the system is greatly simplified, and the energy consumption is also effectively reduced.

Description

Technical Field

[0001] The invention belongs to anthracene oil refining technology, and in particular relates to a process for refining anthracene oil from coal tar. Background Art

[0002] The components produced during the distillation and separation of high-temperature coal tar include light oil, phenol oil, naphthalene oil, washing oil, anthracene oil, asphalt and other components. Among them, anthracene oil is the main raw material for extracting fluorene, anthracene and carbazole. A typical composition of mixed anthracene oil is 8.54% fluorene, 24.52% phenanthrene, 7.39% anthracene and 4.14% carbazole. At the same time, since the boiling points of anthracene and phenanthrene are too close, it is difficult to separate the two. To address this problem, the existing processing techniques include solvent extraction and solvent distillation. The present invention improves the solvent extraction method, wherein the solvent extraction method uses crude anthracene as raw material for processing. The main process is: using a first type of solvent (benzene) to separate impurities such as phenanthrene and fluorene from crude anthracene, enriching anthracene and carbazole and completing the first mother liquor regeneration cycle; using a second type of solvent (pyridine) to extract carbazole. The raffinate phase after extraction with the two solvents is refined anthracene, and then centrifugal drying is performed to obtain a refined anthracene solid product containing more than 90% anthracene. Anthracene oil needs to be extracted twice, and each extraction requires a fractionation cycle of the extractant, which leads to problems of cumbersome system, complex process, high energy consumption and high cost. Summary of the invention

[0003] The technical problem to be solved by the present invention is that the existing technology for refining anthracene oil requires two extractions of anthracene oil, and each extraction requires a fraction circulation operation of the extractant, which leads to the problems of cumbersome system, complex process, high energy consumption and high cost.

[0004] In order to solve the above technical problems, the inventors have obtained the technical solution of the present invention through practice and summary. The present invention adopts the following technical solution:

[0005] The process of refining anthracene oil from coal tar has the following steps:

[0006] Step 1: Light oil fraction

[0007] Coal tar is pumped into the light fraction tower through the raw material tank, the light fraction is extracted from the top of the light fraction tower and enters the reflux tank through the condenser, and the anthracene oil-asphalt mixed oil fraction is extracted from the bottom of the tower;

[0008] Step 2, anthracene oil fraction is taken

[0009] The anthracene oil fraction is extracted from the top of the two oil mixing towers and enters the refining tower in liquid form through the condenser;

[0010] Asphalt fractions are extracted from the bottom of the two oil mixing towers;

[0011] Step 3, Refining

[0012] The refining tower is provided with a No. 1 refining chamber, a No. 2 refining chamber and a vertical partition between the two, a filter screen is installed in the middle of the vertical partition, and the No. 1 refining chamber and the No. 2 refining chamber are both variable volume chambers;

[0013] The anthracene oil enters the No. 1 refining chamber of the refining tower, and a suitable amount of extractant A is added into the No. 1 refining chamber to obtain a mixed oil component;

[0014] The mixed oil is separated into the No. 2 refining chamber of the refining tower, cooled and crystallized to obtain a lower solid phase and an upper liquid phase, and the upper liquid phase is returned to the No. 1 refining chamber; an appropriate amount of extractant B is added to the No. 2 refining chamber, mixed and dissolved to obtain a lower anthracene-rich phase and an upper extraction phase, the upper extraction phase is returned to the No. 1 refining chamber and mixed with the upper liquid phase to obtain a mixed phase, and the distillate is fed into the separation tower through a pipeline to obtain extractant A, extractant B, phenanthrene-containing oil, and carbazole-containing oil;

[0015] Step 4, centrifugal drying

[0016] The lower anthracene-rich phase is placed in a centrifuge for centrifugal drying to obtain refined anthracene.

[0017] Preferably, a circulating water jacket is provided on the outer side of the refining tower, a circulating water inlet and a circulating water outlet are provided on the circulating water jacket, and a digital thermometer is provided inside the refining tower.

[0018] Preferably, the interior of the No. 1 refining chamber and the No. 2 refining chamber are both vertically slidably provided with bottom plates, both sides of the bottom plates are provided with sealing strips, a connecting frame is installed on the bottom plates, and a telescopic cylinder is installed on the top of the No. 1 refining chamber and the No. 2 refining chamber, and the output end of the telescopic cylinder is connected to the connecting frame, which is used to drive the bottom plates to move up and down to change the cavity space of the No. 1 refining chamber and the No. 2 refining chamber;

[0019] The inner top of the No. 1 refining chamber is provided with an extractant A filling pipe and an anthracene oil filling pipe.

[0020] Preferably, a snap-fit ​​groove is provided at the bottom of the vertical partition, and a sealing clip is provided at the inner bottom of the refining tower, and the sealing clip and the snap-fit ​​groove are in a sealed state in a socket-and-socket fit.

[0021] Preferably, a rotating plate is installed on the bottom plate of the second refining chamber, and the rotating plate and the injection nozzles are evenly arranged on the rotating plate in the circumferential direction. The injection nozzles are offset at the same angle as the radial direction of the rotating plate, and the injection angles of the injection nozzles are all set obliquely upward and toward the outside. The bottom center of the rotating plate is connected to the extractant B filling pipe through a rotating joint;

[0022] A washing motor is installed on the bottom plate at this location, a gear is installed on the output end of the washing motor, a transmission gear ring is arranged on the outer side of the rotating plate, and the gear and the transmission gear ring are meshed and matched.

[0023] Preferably, an annular groove is provided at the bottom of the rotating plate, a roller is provided in the annular groove, an L-shaped plate is installed at the bottom of the bottom plate, and a spherical rolling groove for accommodating the roller is provided at the top of the horizontal section of the L-shaped plate.

[0024] Preferably, the top of the refining tower is provided with an insertion groove and a horizontal groove, the insertion groove is used for vertically inserting the vertical partition, the horizontal groove is located on one side of the insertion groove, a guide rod is installed inside the horizontal groove, a spring and a plug-in rod are mounted on the outer side of the guide rod, a limiting hole is provided on the top of the vertical partition, and the plug-in rod and the limiting hole are horizontal socket devices.

[0025] Preferably, an extrusion portion is provided at the bottom of the plug-in rod, and the thickness of the extrusion portion gradually increases in a direction away from the vertical partition.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The present invention adopts extractant A to be filled in liquid form, and mixed with anthracene oil fraction in No. 1 refining chamber, the two enter into No. 2 refining chamber in the form of mixed liquid through the filter screen plate, and cooling water is continuously introduced into No. 2 refining chamber through the circulating water jacket to complete crystallization, and the extraction phase is returned to No. 1 refining chamber through the filter screen plate, and then the extraction agent B is introduced into No. 2 refining chamber to perform secondary extraction on the residual phase of the extraction, and after the secondary extraction, the secondary extraction phase enters No. 1 refining chamber through the filter screen plate to obtain a mixed phase, and then enters the internal fraction of the separation tower together to obtain extractant A, extractant B, phenanthrene oil, and carbazole oil, which can greatly improve the separation efficiency, and by completing a double separation operation in a tower in the refining tower, the process steps are greatly simplified, the system is greatly simplified, and the energy consumption is also effectively reduced. The washing of No. 1 refining chamber can be completed by continuing to introduce extractant A, and its washing liquid also enters the fraction tower.

[0028] 2. The present invention adopts a circulating cooling water jacket to complete the cooling crystallization after extraction, and utilizes crystallization and secondary extraction in the No. 2 refining chamber, which can greatly simplify the system and process steps. Multiple secondary extractions can be performed in the No. 2 refining chamber according to actual needs, so that the primary extraction and secondary extraction liquid are mixed in the No. 1 refining chamber, and enter the distillation tower together to complete a separation, thereby realizing the recycling of the extractant.

[0029] 3. The present invention also improves the refining tower by adopting a variable volume chamber, which can effectively separate the internal extract and the residual phase. Secondly, the extraction agent B is added into the second refining chamber and the rotary jet is used to efficiently complete the extraction operation and obtain a higher purity anthracene.

[0030] 4. The present invention also adds a structure inside the refining tower to facilitate the replacement of the filter screen plate, and uses a plug-in rod to socket-fit the limiting holes on the vertical partition plate while plugging and matching the bottom clamping groove and the sealing clamp plate to form a sealed state, thereby ensuring the bottom sealing effect between the No. 1 refining tower and the No. 2 refining tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the system structure of the present invention.

[0032] Figure 2 It is a schematic diagram of the structure inside the refining tower of the present invention.

[0033] Figure 3 for Figure 2 A partial enlarged view of point A in the middle.

[0034] Figure 4 for Figure 2 A partial enlarged view of point B in the middle.

[0035] Figure 5 for Figure 2 A partial enlarged view of point C in the middle.

[0036] Figure 6 A top view of the rotating plate.

[0037] Figure 7 This is a bottom view of the rotating plate.

[0038] Figure 8 This is a diagram showing the position relationship between the rotating plate and the base plate. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0040] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0041] like Figure 1 As shown in the figure, the process of refining anthracene oil from coal tar has the following steps:

[0042] Step 1: Light oil fraction

[0043] Coal tar is pumped into the light fraction tower 20 through the raw material tank 10, and the light fraction is extracted from the top of the light fraction tower 20 and enters the reflux tank 30 through the condenser, and the anthracene oil-asphalt two mixed oil fractions are extracted from the bottom of the tower;

[0044] Step 2, anthracene oil fraction is taken

[0045] The anthracene oil fraction is extracted from the top of the two oil mixing towers 40 and enters the refining tower 50 in liquid form through the condenser;

[0046] Asphalt fraction is extracted from the bottom of two oil mixing towers 40;

[0047] Step 3, Refining

[0048] The refining tower 50 is provided with a first refining chamber 51, a second refining chamber 52 and a vertical partition 53 located therebetween. A filter screen plate 54 is installed in the middle of the vertical partition 53. Both the first refining chamber 51 and the second refining chamber 52 are variable volume chambers.

[0049] The anthracene oil enters the first refining chamber 51 of the refining tower 50, and a suitable amount of extractant A is added into the first refining chamber 51 to obtain a mixed oil component;

[0050] The mixed oil is separated into the second refining chamber 52 of the refining tower 50, cooled and crystallized to obtain a lower solid phase and an upper liquid phase, and the upper liquid phase is returned to the first refining chamber 51; an appropriate amount of extractant B is added to the second refining chamber 52, mixed and dissolved to obtain a lower anthracene-rich phase and an upper extraction phase, and the upper extraction phase is returned to the first refining chamber 51 to mix with the upper liquid phase to obtain a mixed phase, which is distilled into the separation tower 60 through a pipeline to obtain extractant A, extractant B, phenanthrene-containing oil, and carbazole-containing oil;

[0051] Step 4, centrifugal drying

[0052] The lower anthracene-rich phase is placed in a centrifuge 70 for centrifugal drying to obtain refined anthracene.

[0053] In the above scheme, the crystallization operation of the mixed oil is carried out in the second refining chamber 52, such as Figure 2 As shown, a circulating water jacket 501 is provided on the outside of the refining tower 50, and a circulating water inlet 502 and a circulating water outlet 503 are provided on the circulating water jacket 501, and a digital thermometer 504 is provided inside the refining tower 50. The digital thermometer 504 is used to accurately control the temperature to ensure the internal crystallization effect and efficiency, and the method of cooling water inlet at the top and outlet at the bottom is conducive to crystallization.

[0054] In the above scheme, the variable volume effect is achieved in the first refining chamber 51 and the second refining chamber 52, such as Figure 2As shown, the interior of the No. 1 refining chamber 51 and the No. 2 refining chamber 52 are both vertically slidably provided with a bottom plate 55, and sealing strips are provided on both sides of the bottom plate 55. A connecting frame 56 is installed on the bottom plate 55, and a telescopic cylinder 57 is installed on the top of the No. 1 refining chamber 51 and the No. 2 refining chamber 52. The output end of the telescopic cylinder 57 is connected to the connecting frame 56, which is used to drive the bottom plate 55 to move up and down to change the cavity space of the No. 1 refining chamber 51 and the No. 2 refining chamber 52; the bottom plate 55 is driven to move up and down by the telescopic cylinder 57 through the connecting frame 56, and the sealing is ensured to be leak-proof under the action of the sealing strip.

[0055] An extractant A filling pipe 58 and an anthracene oil filling pipe 59 are provided at the inner top of the first refining chamber 51 for quantitative filling.

[0056] A bellows 552 is installed on the bottom plate 55 located inside the No. 1 refining chamber 51, the top of the bellows 552 is connected to the No. 1 refining chamber 51, and the bottom is connected to the mixed phase discharge pipe 554; a bellows 552 is also installed on the bottom plate 55 located inside the No. 2 refining chamber 52, the top of the bellows 552 is connected to the No. 2 refining chamber 52, and the bottom is connected to the refined anthracene discharge pipe 553.

[0057] In the above scheme, to ensure the sealing effect, Figure 5 As shown, a snap-in groove 531 is provided at the bottom of the vertical partition 53, and a sealing snap-in plate 532 is provided at the inner bottom of the refining tower 50. The sealing snap-in plate 532 and the snap-in groove 531 are plug-fitted and sealed.

[0058] In the above scheme, in order to achieve efficient secondary extraction effect, as Figure 3 , 6 As shown, a rotating plate 533 is installed on the bottom plate 55 of the second refining chamber 52, and the rotating plate 533 and the injection nozzles 534 are evenly arranged on the rotating plate 533 in the circumferential direction. The injection nozzles 534 are offset at the same angle as the radial direction of the rotating plate 533, and the injection angles of the injection nozzles 534 are all inclined upward and toward the outside. The bottom center of the rotating plate 533 is connected to the extractant B filling pipe 535 through a rotating joint; the rotating plate 533 is rotated to allow the injection nozzles 534 to rotate and inject in a rotational direction to extract the crystals, and the extraction effect is thorough and efficient.

[0059] A washing motor 537 is installed on the bottom plate 55, and a gear 538 is installed on the output end of the washing motor 537. A transmission gear ring 536 is provided on the outer side of the rotating plate 533, and the gear 538 and the transmission gear ring 536 are meshed and matched.

[0060] In the above scheme, in order to ensure the rotation support of the rotating plate 533, as Figure 2 , 7As shown in FIG. 8 , an annular groove 539 is provided at the bottom of the rotating plate 533, and a roller 5311 is provided in the annular groove 539 . An L-shaped plate 5310 is installed at the bottom of the bottom plate 55, and a spherical rolling groove for accommodating the roller 5311 is provided at the top of the horizontal section of the L-shaped plate 5310.

[0061] In the above scheme, in order to facilitate the vertical disassembly and replacement of the filter screen plate 54 of the vertical partition 53 and the effect of the bottom sealing state after disassembly and assembly, as shown in FIG. Figure 4 As shown, the top of the refining tower 50 is provided with an insertion slot 5312 and a horizontal slot 5313. The insertion slot 5312 is used to vertically insert the vertical partition 53. The horizontal slot 5313 is located on one side of the insertion slot 5312. A guide rod 5315 is installed inside the horizontal slot 5313. A spring and a plug rod 5314 are sleeved on the outer side of the guide rod 5315. A limiting hole 5316 is provided on the top of the vertical partition 53. The plug rod 5314 and the limiting hole 5316 are horizontally inserted. An extrusion portion is provided at the bottom of the plug rod 5314, and the thickness of the extrusion portion gradually increases in the direction away from the vertical partition 53. The filter screen plate 54 on the vertical partition 53 is replaced by separating the plug rod 5314 and the limiting hole 5316, and the extrusion portion at the bottom of the plug rod 5314 is used to ensure the sealing effect.

[0062] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. The replacement can be a replacement of part of the structure, device, method step, or a complete technical solution. The above-mentioned extractants are all commonly used extractants for preparing anthracene oil, and the mixing ratios are all traditional mixing ratios. Equivalent replacements or changes according to the technical solution of the present invention and its inventive concept should be covered within the protection scope of the present invention.

Claims

1. A process for refining anthracene oil from coal tar, characterized in that: The process steps are as follows: Step 1: Light oil fraction Coal tar is pumped into a light fraction tower (20) through a raw material tank (10); a light fraction is extracted from the top of the light fraction tower (20) and enters a reflux tank (30) through a condenser; and anthracene oil-asphalt mixed oil fractions are extracted from the bottom of the tower; Step 2, anthracene oil fraction is taken The anthracene oil fraction is extracted from the top of the two oil mixing towers (40) and enters the refining tower (50) in liquid form through a condenser; Extracting asphalt fraction from the bottom of two oil mixing towers (40); Step 3, Refining A first refining chamber (51), a second refining chamber (52) and a vertical partition (53) located therebetween are arranged in the refining tower (50), a filter screen plate (54) is installed in the middle of the vertical partition (53), and both the first refining chamber (51) and the second refining chamber (52) are variable volume chambers; The anthracene oil enters the first refining chamber (51) of the refining tower (50), and a suitable amount of extractant A is added into the first refining chamber (51) to obtain a mixed oil component; The mixed oil is separated into the second refining chamber (52) of the refining tower (50), cooled and crystallized to obtain a lower solid phase and an upper liquid phase, and the upper liquid phase is returned to the first refining chamber (51); an appropriate amount of extractant B is added to the second refining chamber (52), mixed and dissolved to obtain a lower anthracene-rich phase and an upper extraction phase, the upper extraction phase is returned to the first refining chamber (51) and mixed with the upper liquid phase to obtain a mixed phase, and the mixed phase is distilled into the separation tower (60) through a pipeline to obtain extractant A, extractant B, phenanthrene-containing oil, and carbazole-containing oil; Step 4, centrifugal drying The lower anthracene-rich phase is placed in a centrifuge (70) for centrifugal drying to obtain refined anthracene.

2. The process for refining anthracene oil from coal tar according to claim 1, characterized in that: The outer side of the refining tower (50) is provided with a circulating water jacket (501), and the circulating water jacket (501) is provided with a circulating water inlet (502) and a circulating water outlet (503). The interior of the refining tower (50) is provided with a digital thermometer (504).

3. The process for refining anthracene oil from coal tar according to claim 2, characterized in that: The first refining chamber (51) and the second refining chamber (52) are both provided with a bottom plate (55) for vertical sliding, and sealing strips (551) are provided on both sides of the bottom plate (55). A connecting frame (56) is installed on the bottom plate (55). A telescopic cylinder (57) is installed on the top of the first refining chamber (51) and the second refining chamber (52). The output end of the telescopic cylinder (57) is connected to the connecting frame (56) for driving the bottom plate (55) to move up and down to change the cavity space of the first refining chamber (51) and the second refining chamber (52); The top of the inner side of the first refining chamber (51) is provided with an extractant A filling pipe (58) and an anthracene oil filling pipe (59).

4. The process for refining anthracene oil from coal tar according to claim 3, characterized in that: The bottom of the vertical partition (53) is provided with a clamping groove (531), and the inner bottom of the refining tower (50) is provided with a sealing clamping plate (532), and the sealing clamping plate (532) and the clamping groove (531) are socket-fitted and sealed.

5. The process for refining anthracene oil from coal tar according to claim 4, characterized in that: A rotating plate (533) is installed on the bottom plate (55) of the second refining chamber (52), the rotating plate (533) and injection nozzles (534) uniformly arranged on the rotating plate (533) in the circumferential direction, the injection nozzles (534) are offset at the same angle as the radial direction of the rotating plate (533), the injection angle of the injection nozzles (534) is inclined upward and toward the outside, and the bottom center of the rotating plate (533) is connected to an extractant B filling pipe (535) through a rotating joint; A washing motor (537) is installed on the bottom plate (55) at this location, a gear (538) is installed on the output end of the washing motor (537), a transmission gear ring (536) is arranged on the outer side of the rotating plate (533), and the gear (538) and the transmission gear ring (536) are meshed and matched.

6. The process for refining anthracene oil from coal tar according to claim 5, characterized in that: The bottom of the rotating plate (533) is provided with an annular groove (539), and a roller (5311) is arranged in the annular groove (539). The bottom of the bottom plate (55) is installed with an L-shaped plate (5310), and the top of the horizontal section on the L-shaped plate (5310) is provided with a spherical rolling groove for accommodating the roller (5311).

7. The process for refining anthracene oil from coal tar according to claim 6, characterized in that: The top of the refining tower (50) is provided with an insertion groove (5312) and a horizontal groove (5313), the insertion groove (5312) is used for vertically inserting the vertical partition (53), the horizontal groove (5313) is located on one side of the insertion groove (5312), a guide rod (5315) is installed inside the horizontal groove (5313), a spring and a plug rod (5314) are sleeved on the outer side of the guide rod (5315), a limiting hole (5316) is provided on the top of the vertical partition (53), and the plug rod (5314) and the limiting hole (5316) are horizontal socket devices.

8. The process for refining anthracene oil from coal tar according to claim 7, characterized in that: The bottom of the plug-in rod (5314) is provided with an extrusion portion, and the thickness of the extrusion portion gradually increases in a direction away from the vertical partition (53).

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