Perforated disc type liquid phase splitter for cyclohexanone oxime liquid phase rearrangement product

Abstract

The invention provides a porous disc type liquid phase splitter for cyclohexanone oxime liquid phase rearrangement products, the porous disc type liquid phase splitter is arranged in the middle in a phase splitting tower and used for liquid phase splitting, the porous disc type liquid phase splitter comprises a liquid distribution disc and a liquid guide pipe, and the liquid guide pipe is composed of a supporting pipe and a phase splitting structure which are connected with each other; and the liquid guide pipe is vertical to the liquid distribution disc. According to the phase splitter, mass transfer can be enhanced through the designed special liquid guide pipe, and feed liquid can be efficiently mixed; a uniform split-phase space is formed in each stage of liquid distribution disc space, so that the purpose of multi-stage extraction is achieved, and separation work such as extraction, back extraction and ion exchange can be completed by a single extraction tower; meanwhile, the mixing efficiency and the mass transfer performance of the feed liquid can be improved, the occupied space is smaller, the installation is convenient, and the levelness is easy to adjust.

Description

Technical Field

[0001] The invention relates to the technical field of nylon 66 preparation, and in particular to a perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products. Background Art

[0002] Caprolactam is an important intermediate in the nylon industry chain. At present, the mainstream production process of caprolactam is to first use benzene to make cyclohexanone, then react with hydroxylamine to prepare cyclohexanone oxime, and then use fuming sulfuric acid to perform Beckmann rearrangement to generate a caprolactam sulfuric acid mixture, and then generate a crude caprolactam liquid containing ammonium sulfate through neutralization and crystallization, and then purify the crude caprolactam liquid through a refining unit. Among them, 60%-70% of the crude caprolactam liquid is caprolactam, and the rest is impurities such as ammonium sulfate, water, cyclohexanone, benzene, toluene, and cyclohexanol. The current research hotspot in related fields is the efficient refining method of crude caprolactam liquid.

[0003] Some researchers have studied the process flow of crude caprolactam liquid refining. For example, patent CN201620239506.2 reports a caprolactam refining device, which consists of an extraction tower, a refining tower, a hydrogenation reactor, a light removal tower, a distillation and other devices. The method simplifies the process flow relatively. Patent CN201711000196.4 reports a method for refining caprolactam; the process includes extraction, hydrogen peroxide washing, back extraction, ion exchange, etc.; the method prolongs the life of the ion exchange resin. Patent CN201621187626.9 reports a low-energy consumption caprolactam refining device; compared with the traditional caprolactam refining process, an alkali washing tower, an acid washing tower, and a heavy removal tower are added, and water extraction, evaporation and other processes are reduced, reducing the generation of wastewater. However, limited by the efficiency of the extraction unit, the refining effect of the above design is poor.

[0004] In addition, the laboratory found in the process of refining process optimization that the efficient separation of caprolactam, water and ammonium sulfate in the extraction step can effectively reduce the refining process and reduce the proportion of polymerization side reactions of caprolactam. The key to efficient separation in the extraction step is the design of the phase separator of the extraction tower. Patents have been published to optimize the structure of the stirring paddle and enhance mass transfer. For example, CN220758739U reports an efficient liquid dispersion device, but the mass transfer enhancement effect of this patent is still limited. Analyzing the reasons, the above-mentioned extraction improvement device does not take into account strong mass transfer disturbance and multi-stage extraction. Therefore, it is necessary to further optimize the structure of the extraction device.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The object of the present invention is to provide a perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products, wherein the phase separator can enhance mass transfer and efficiently mix feed liquid through a liquid guide tube in a special perforated disc phase separator; secondly, multiple liquid distribution plates are evenly distributed to form a phase separation space, thereby achieving the purpose of multi-stage extraction, thereby realizing that a single tower can complete traditional extraction, back extraction, ion exchange and other separation tasks.

[0007] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted: The present invention provides a perforated disc type liquid phase separator for cyclohexanone oxime liquid phase rearrangement products. The perforated disc type liquid phase separator is arranged in the middle of a phase separation tower for liquid phase separation, and comprises: a liquid distribution disc and a liquid guide tube, wherein the liquid guide tube is composed of a supporting tube and a phase separation structure connected to each other; and the liquid guide tube is arranged perpendicular to the liquid distribution disc.

[0008] The perforated disc phase separator is provided with a supporting device, which can support the perforated disc phase separator in the phase separation tower. The supporting device can also drive the perforated disc phase separator to rotate. The rotation rate of the perforated disc phase separator is 0-400rpm, and different rotation rates can be selected according to the properties of the liquid to be separated. When the viscosity of the liquid is large, a smaller rotation rate is selected, and when the viscosity is small, a larger rotation rate is selected. The perforated disc phase separator is arranged in the middle of the body of the phase separation tower, which is convenient for the extraction or back extraction of liquids with different properties. The perforated disc phase separator is opposite to the center of the phase separation tower, which is convenient for the rotation of the perforated disc phase separator in the phase separation tower without touching the tower wall, and is convenient for disassembly and assembly; at the same time, it is convenient for better phase separation.

[0009] The perforated disc phase separator is mainly composed of a liquid distribution plate and a conduit. The design of the liquid distribution plate and the conduit allows liquids of different properties to pass through, thereby achieving phase separation. The liquid conduit is divided into a heavy phase descending tube and a light phase ascending tube. The heavy phase descending tube is inverted and set on the liquid distribution plate, opposite to the light phase ascending tube.

[0010] Preferably, as a further specific implementation, the phase separation structure is mainly composed of a diffusion zone and a mixing zone, and the diffusion zone connects the mixing zone and the support tube; the diffusion zone is a truncated cone structure, and the portion connected to the mixing zone is expanded.

[0011] Preferably, as a further specific implementation, the phase separation structure further includes a plurality of disturbance plates, and the disturbance plates are disc-shaped structures with a central opening, and are arranged on the mixing zone through the central opening.

[0012] The support tube of the liquid guide tube is connected to the diffusion zone, and the connection part between the diffusion zone and the mixing zone is expanded; the diffusion zone presents a frustum structure, and the diameter gradually increases. On the one hand, the slow increase in diameter can gradually slow down the flow rate of the liquid, so that the liquid can be decelerated in the diffusion zone and enter the mixing zone, and under the action of the disturbance plate, it can be quickly and efficiently separated; on the other hand, the diffusion angle of the diffusion zone is set at 10°-60°, which can also better ensure the dispersion and mixing of the rising or falling liquid.

[0013] A plurality of disturbance plates are arranged on the mixing zone of the liquid guiding tube. The disturbance plates can rotate under the action of the phase separation driving force to separate the liquid to be separated, so that the extraction liquid and the liquid to be separated are fully separated and fully extracted.

[0014] Preferably, as a further specific implementation, the liquid distribution tray is divided into an upper tray surface and a lower tray surface, and the liquid guide tubes are evenly distributed in the upper tray surface and the lower tray surface.

[0015] Preferably, as a further specific implementation, the pipe openings of the mixing zone located on the upper disk surface and the pipe openings of the mixing zone located on the lower disk surface are opposite to each other.

[0016] The two liquid phases are mixed at the outlet of the mixing zone. When the mixing zones are one-to-one opposite to each other, the raw material moving from top to bottom and the extract moving from bottom to top can be fully mixed at the outlet of the mixing zone.

[0017] Preferably, as a further specific implementation, the support tube passes through the upper disk surface or the lower disk surface, and the bottom of the support tube is flush with the surface of the liquid distribution tray.

[0018] In the present invention, the distance between the upper and lower disks of the liquid distribution disk is 0.2-1.5 times the diameter of the phase separation tower. The distance between the upper and lower disks cannot be too large or too small. When the distance between the upper and lower disks is too small, incomplete phase separation may result. During the phase separation process, low-density liquid moves upward under the action of the phase separation driving force. When the distance between the liquid distribution disks is too large, low-density liquid may not be able to accurately enter the corresponding liquid guide tube, thereby causing loss.

[0019] The diameter of the liquid distribution plate is 0.5-0.98 times the diameter of the phase separation tower. The thickness of the upper plate surface and the lower plate of all the liquid distribution plates in the perforated disc phase separator are equal, about 5mm-40mm. The diameter of the liquid distribution plate is smaller than the overall diameter of the phase separation tower, and at the same time larger than 0.5 times the diameter of the phase separation tower, ensuring that the volume of the perforated disc phase separator occupies a larger position in the phase separation tower, preventing the liquid from running around, further ensuring complete phase separation, and improving phase separation efficiency.

[0020] The mixing area of ​​each liquid guide tube vertically penetrates the upper disk or the lower disk, and the liquid guide tubes are evenly and vertically distributed in the liquid distribution tray. At the same time, the support tubes in the liquid guide tubes are embedded in the upper and lower disks of the liquid distribution tray. The embedding depth can be determined according to the actual use situation, but the liquid guide tubes need to be sealed on the contact surface of the upper or lower disk without gaps to ensure the sealing of the liquid guide tubes in the upper and lower disks, so as to reduce the liquid loss during the phase separation process; at the same time, the bottom of the support tube is flush with the upper or lower disk of the liquid distribution tray, without protrusions, which can facilitate the entry of liquid and improve the phase separation efficiency. In addition, the parallel one-to-one relationship between the liquid guide tubes can ensure that the high-density liquid can accurately enter the corresponding liquid guide tube during the movement from top to bottom and the low-density liquid can accurately enter the corresponding liquid guide tube during the movement from bottom to top, and perform the next phase separation. Thereby, multi-stage phase separation is realized, and the purpose of multi-stage extraction is achieved, thereby improving the phase separation efficiency.

[0021] Preferably, as a further specific implementation, the perforated disc phase separator is composed of 40-60 layers of liquid distribution discs, all the liquid distribution discs are located opposite to each other, and the liquid distribution discs are equidistant from each other.

[0022] In the present invention, a multi-stage liquid distribution tray is designed to match the height of the phase separation tower on the one hand, and to improve the phase separation efficiency as much as possible. Therefore, the number of liquid distribution trays is set to 40-60 layers, which can improve the phase separation efficiency at a limited height.

[0023] Preferably, as a further specific implementation, the diffusion angle of the diffusion zone is 10°-60°.

[0024] Preferably, as a further specific implementation, the total area of ​​the support tube of the liquid guiding tube is 20%-80% of the area of ​​the liquid distribution tray.

[0025] In actual application, the number of liquid guide tubes to be installed can be selected according to the properties of the selected liquid, but the area occupied by the liquid guide tubes cannot be less than 20%, otherwise the extraction efficiency will be reduced; since the support tube of the liquid guide tube itself is a hollow cylindrical structure, it is difficult to achieve 100% full coverage of the liquid distribution plate. In actual application, as many liquid guide tubes as possible can be set according to the properties of the liquid.

[0026] Preferably, as a further specific embodiment, the vertical height of the diffusion zone of the liquid guiding tube is 0.3-1.5 times the vertical height of the supporting tube; The vertical height of the mixing zone of the liquid guiding tube is 0.3-1.5 times the vertical height of the supporting tube, and the diameter of the mixing zone is 1.2-4 times the diameter of the supporting tube.

[0027] The vertical height of the diffusion zone is 0.3-1.5 times the vertical height of the support tube. When encountering a liquid that is difficult to separate and requires as much mixing as possible, its vertical height is 1-1.5 times the vertical height of the support tube; and when the liquid is relatively easy to separate, its vertical height is 0.3-1 times the vertical height of the support tube.

[0028] A diffusion zone is provided between the mixing zone and the support tube for diffusing the liquid, so the diameter of the final mixing zone is larger than the diameter of the support tube. In the actual setting process, it is necessary to consider multiple properties such as the size of the liquid distribution plate, the properties of the liquid itself, and the liquid flow rate, so the diameter of the mixing zone is set to 1.2-4 times the diameter of the support tube; it can ensure that the liquid passes through the mixing zone at a moderate flow rate and is fully mixed in the mixing zone; it can also make the size of the mixing zone moderate, increase the number of liquid guide tubes set in the liquid distribution plate, and avoid reducing the number of liquid guide tubes due to excessive mixing zones of the liquid guide tubes.

[0029] The diameter of the disturbance plate is 0.1-0.45 times the diameter of the mixing zone; the height of the disturbance plate is 0.2-0.8 times the height of the mixing zone.

[0030] The disturbance plate is arranged in the mixing area. Since the mixing area is a cylindrical structure, multiple disturbance plates can be arranged. During the arrangement, the distance between the disturbance plates needs to be controlled to improve the mixing efficiency.

[0031] The distance between the upper and lower disk surfaces of the liquid distribution disk is 0.2-1.5 times the diameter of the phase separation tower.

[0032] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention can enhance mass transfer and efficiently mix the feed and liquid through the specially designed liquid guide tube; each level of the liquid distribution plate space forms a uniform phase separation space to achieve the purpose of multi-stage extraction, and a single extraction tower can complete extraction, back extraction and ion exchange and other separation work; at the same time, it can improve the mixing efficiency and mass transfer performance of the feed and liquid, and has the advantages of smaller occupied space, convenient installation and easy adjustment of the horizontality.

[0033] (2) The efficiency of the extraction device is effectively improved, and the equipment and operation costs are greatly reduced. In addition, it is known that the sulfide in the crude caprolactam-extractant mixture has a great influence on the conversion rate and selectivity of the subsequent amination reaction. Therefore, the above advantages make the present invention have extremely high economic benefits in the field of nylon new material preparation. At the same time, it can effectively shorten the process flow, which is more meaningful for application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1 : Schematic diagram of perforated disc liquid phase separator; Figure 2 : Structure diagram of the liquid guide tube in the perforated disc liquid phase separator; Figure 3 : The position of the perforated disc liquid phase separator in the phase separation tower.

[0035] The symbols in the accompanying drawings are: 1. Liquid distribution plate-lower plate surface; 2. Diffusion zone; 3. Mixing zone; 4. Disturbance plate; 5. Support tube; 6. Liquid guide tube - heavy phase descending tube; 7. Liquid guide tube - light phase ascending tube; 8. Liquid distribution plate - upper plate surface; Phase separation tower; 10. Raw material inlet; 11. Extractant inlet; 12. Waste liquid outlet; 13. Perforated disc phase separator. DETAILED DESCRIPTION

[0036] The technical scheme of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but it will be understood by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0037] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the 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 limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In order to more clearly explain the technical solution of the present invention, it is described in the form of specific embodiments below.

[0040] Example 1 The structure of the perforated disk liquid phase separator for the liquid phase rearrangement products of cyclohexanone oxime, such as Figure 1 and Figure 2 As shown, it is a schematic diagram of a perforated disc liquid phase separator and a structure diagram of a liquid guide tube in a perforated disc liquid phase separator. It can be seen from the figure that a perforated disc liquid phase separator is composed of multiple layers of liquid distribution discs, and a liquid distribution disc is composed of a liquid distribution disc-lower disc surface 1 and a liquid distribution disc-upper disc surface 8. The lower disc surface serves as the upper disc surface of another liquid distribution disc, and the hierarchical structure of the perforated disc phase separator 13 is alternately formed. The perforated disc phase separator has a total of 40-60 levels. The distance between the liquid distribution disc-lower disc surface 1 and the liquid distribution disc-upper disc surface 8 is 0.2-1.5 times the diameter of the phase separation tower. A plurality of liquid guide tubes are arranged on the top of each liquid distribution tray, and the liquid guide tubes are divided into liquid guide tube-heavy phase descending tube 6 and liquid guide tube-light phase ascending tube 7. The support tube 1 vertically penetrates the upper disk surface or the lower disk surface of the liquid distribution tray, and the liquid guide tubes are evenly distributed on the upper disk surface or the lower disk surface of the liquid distribution tray, and each liquid guide tube is parallel to each other. The liquid guide tube-heavy phase descending tube 6 and the liquid guide tube-light phase ascending tube 7 correspond one by one, and the liquid guide tube-light phase ascending tube 7 is inverted in the disk surface of the liquid distribution tray. The bottom of the support tube 5 is flush with the upper disk surface or the lower disk surface of the liquid distribution tray (i.e., there is no protrusion). The total area of ​​the support tube 5 accounts for 20%-80% of the total area of ​​the liquid distribution tray.

[0041] from Figure 2The structure of the liquid guide tube can be seen in the figure. The liquid guide tube consists of a support tube 5, a diffusion zone 2, a mixing zone 3 and a disturbance plate 4. The support tube 5 is directly connected to the diffusion zone 2, and the vertical height of the diffusion zone 2 is 0.3-1.5 times the vertical height of the support tube 5, and the diffusion angle of the diffusion zone 2 is 10°-60°. The connecting part of the diffusion zone 2 and the mixing zone 3 is expanded, and the diffusion zone 2 is a truncated cone structure as a whole. The diameter of the mixing zone 3 is equal to the diameter of the diffusion zone 2 after expansion, and the mixing zone 3 is cylindrical. A disturbance plate 4 is provided in the mixing zone 3. The disturbance plate 4 is a cylindrical structure, and the vertical height of the disturbance plate 4 is 0.2-0.8 times the vertical height of the mixing zone 3. The diameter of the disturbance plate 4 is 0.1-0.45 times the diameter of the mixing zone 3. In addition, the vertical height of the mixing zone 3 is 0.3-1.5 times the vertical height of the support tube 5.

[0042] from Figure 3 It can be seen that the position of the perforated disc liquid phase separator 10 in the phase separation tower, the perforated disc liquid phase separator 13 is located in the middle position of the phase separation tower 9, the raw material inlet 10 is located at the upper part of the perforated disc phase separator 13, the extractant inlet 8 is arranged at the lower part of the perforated disc phase separator 13, and a waste liquid outlet 12 is also arranged at the bottom of the phase separation tower 9.

[0043] Workflow: The raw materials to be separated and the extractant are selected and introduced into the phase separation tower 9 from the raw material inlet 10, and the extractant enters from the extractant inlet 11. The extractant moves from the liquid guide tube-light phase ascending tube 7 from the liquid distribution plate-lower plate surface 1 from bottom to top under the action of the phase separation driving force, and the raw materials to be separated move from the liquid guide tube-heavy phase descending tube 6 from the liquid distribution plate-upper plate surface 8 from top to bottom. When the two raw materials first enter the perforated disc phase separator, they pass through the corresponding support tube 5, diffusion zone 2 and mixing zone 3 respectively.

[0044] The two liquids are continuously moving until the first contact occurs in the gap between the liquid guide tube-light phase ascending tube 7 and the liquid guide tube-heavy phase descending tube 6 in the mixing zone 3 where they are not in contact, and they are continuously mixed in the gap. The mixed liquid then enters the mixing zone 3 of the liquid guide tube, and the disturbance plate 4 in the mixing zone 3 rotates continuously to perform the first phase separation on the mixed liquid. After the first phase separation, the mixed liquid continues to move downward, and the above steps are continuously repeated with the extractant moving from bottom to top, and the extraction is continuously performed until the reaction is completed. The waste liquid is discharged from the waste liquid outlet 12 at the bottom of the phase separation tower 9, and the extracted raw liquid flows out from the top of the phase separation tower 9 into the distillation tower.

[0045] Example 2 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.50% and the ammonium sulfate content was 30 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.20%.

[0046] Example 3 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 1.5 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.56% and the ammonium sulfate content was 100 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.30%.

[0047] Example 4 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.5 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.56% and the ammonium sulfate content was 50 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.26%.

[0048] Example 5 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 30 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.60% and the ammonium sulfate content was 50 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.31%.

[0049] Example 6 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 60 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.58% and the ammonium sulfate content was 50 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.31%.

[0050] Example 7 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 40% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.62% and the ammonium sulfate content was 100 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.25%.

[0051] Example 8 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 70 mm, the inner diameter is 10 mm, and the outer diameter is 20 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.61% and the ammonium sulfate content was 80 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.26%.

[0052] Example 9 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 1 times the vertical height of the support tube domain, and the diffusion angle is 60 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.4 times the diameter of the mixing area, the width is 0.05 times the diameter of the mixing area, and the height is 0.8 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.59% and the ammonium sulfate content was 70 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.24%.

[0053] Example 10 The caprolactam liquid containing ammonium sulfate obtained by the cyclohexanone oxime rearrangement process is used as the raw material liquid (the mass fraction of caprolactam is 80%, the mass fraction of water is 19%, and the mass fraction of ammonium sulfate is 0.6%), benzene is used as the extractant, and an extraction tower equipped with a special perforated disc liquid phase separator is used as the operating equipment, with 40 layers of liquid distribution discs. The diameter of the extraction tower is 1m; the distance between the liquid distribution plates is 0.2 times the tower diameter; the diameter of the liquid distribution plate is 0.95 times the tower diameter; the thickness of the liquid distribution plate is 10 mm; the diameter of the rotating rod of the liquid distribution plate is 30 mm; the rotation speed of the liquid distribution plate is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the plate area; the vertical height of the support tube domain of the liquid guide tube is 20 mm, the inner diameter is 30 mm, and the outer diameter is 40 mm; the vertical height of the diffusion area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diffusion angle is 30 degrees; the vertical height of the mixing area of ​​the liquid guide tube is 0.5 times the vertical height of the support tube domain, and the diameter is 2 times the support tube domain; the length of the disturbance plate is 0.1 times the diameter of the mixing area, the width is 0.1 times the diameter of the mixing area, and the height is 0.2 times the vertical height of the mixing area; the volume flow rate ratio of the extractant to the raw material is 10. A caprolactam benzene solution was obtained at the top of the tower, wherein the water content was 0.59% and the ammonium sulfate content was 10 ppm; an aqueous solution containing ammonium sulfate was obtained at the bottom of the tower, and the COD was 0.26%.

[0054] Embodiment 11 The specific implementation method is consistent with Example 2, except that the number of layers of the liquid distribution tray is set to 60 layers. The final aqueous solution containing ammonium sulfate has a COD of 0.20%.

[0055] Comparative Example 1 The specific implementation method is consistent with Example 2, except that the structure of the liquid guiding tube is changed, and a non-partitioned cylindrical liquid guiding tube is used, and the final measured COD is 0.55%.

[0056] Comparative Example 2 The specific implementation method is consistent with Example 2. The liquid guide tube used is set obliquely to the liquid distribution tray, and the final measured COD is 0.51%.

[0057] It can be seen from Example 2 and Comparative Examples 1-2 that in the present invention, the structure of the liquid distribution plate and the conduit, as well as the liquid conduit itself, is very important. The liquid conduit is divided into partitions, and different partitions have different functions. Among them, the phase separation structure for phase separation can effectively improve the working capacity of the perforated disc liquid distribution phase separator, effectively reduce the COD content in the finished product, and improve the working efficiency, and the support tube can provide effective support for it.

[0058] The liquid guide tube is arranged perpendicular to the liquid distribution plate, so that the liquid to be separated flowing from top to bottom and the extraction liquid flowing from bottom to top can be fully mixed, which effectively improves the reaction rate and has more practical application significance.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products, characterized in that: The perforated plate type liquid phase separator is arranged in the middle of the phase separation tower for liquid phase separation, and comprises: a liquid distribution plate and a liquid guide tube, wherein the liquid guide tube is composed of a supporting tube and a phase separation structure connected to each other; the liquid guide tube is arranged perpendicular to the liquid distribution plate.

2. The perforated disc type liquid phase separator for cyclohexanone oxime liquid phase rearrangement product according to claim 1, characterized in that: The phase separation structure is mainly composed of a diffusion zone and a mixing zone, wherein the diffusion zone connects the mixing zone and the support pipe; the diffusion zone is a truncated cone structure, and the portion connected to the mixing zone is expanded.

3. The perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products according to claim 2, characterized in that: The phase separation structure also includes a plurality of disturbance plates, which are disc-shaped structures with a central opening and are arranged on the mixing zone through the central opening.

4. The perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products according to claim 1, characterized in that: The liquid distribution tray is divided into an upper tray surface and a lower tray surface, and the liquid guide tubes are evenly distributed in the upper tray surface and the lower tray surface.

5. The perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products according to any one of claims 3 to 4, characterized in that: The pipe openings of the mixing zone located on the upper disk surface and the pipe openings of the mixing zone located on the lower disk surface are opposite to each other.

6. The perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products according to any one of claims 3 to 4, characterized in that: The support tube passes through the upper disk surface or the lower disk surface, and the bottom of the support tube is flush with the surface of the liquid distribution tray.

7. The perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products according to claim 4, characterized in that: The number of layers of the liquid distribution pan is 40-60, the centers of the liquid distribution pans in each layer are opposite to each other, and the upper pan surface and the lower pan surface of each liquid distribution pan are equidistantly distributed.

8. The perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products according to claim 2, characterized in that: The diffusion angle of the diffusion zone is 10°-60°.

9. The perforated disc liquid phase separator for cyclohexanone oxime liquid phase rearrangement products according to claim 2, characterized in that: The total area of ​​the support tubes in the liquid guiding tube is 20%-80% of the area of ​​the liquid distribution tray.

10. The perforated disc type liquid phase separator for the liquid phase rearrangement product of cyclohexanone oxime according to claim 2, characterized in that: The vertical height of the diffusion zone of the liquid guiding tube is 0.3-1.5 times the vertical height of the supporting tube; The vertical height of the mixing zone of the liquid guiding tube is 0.3-1.5 times the vertical height of the supporting tube, and the diameter of the mixing zone is 1.2-4 times the diameter of the supporting tube.

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