A well-plate liquid phase separator for cyclohexanone oxime liquid phase rearrangement products

Abstract

The application provides a hole disc type liquid phase separator for cyclohexanone oxime liquid phase rearrangement product, which is arranged in the middle of a phase separation tower for liquid phase separation and comprises a liquid distribution disc and a liquid guide pipe, wherein the liquid guide pipe is composed of a support pipe and a phase separation structure which are connected with each other, and the liquid guide pipe is arranged perpendicularly to the liquid distribution disc. The phase separator can strengthen mass transfer and efficiently mix the liquid through the special liquid guide pipe. The space of each stage of the liquid distribution disc forms a uniform phase separation space, so that the purpose of multi-stage extraction is achieved, and the separation work such as single extraction, back extraction and ion exchange can be completed by a single extraction tower. Meanwhile, the phase separator can improve the mixing efficiency and mass transfer performance of the liquid, has the advantages of smaller occupied space, convenient installation and easy adjustment of the horizontal degree.

Description

Technical Field

[0001] This invention relates to the field of nylon 66 preparation technology, and more specifically, to a perforated disk type liquid phase separator for cyclohexanone oxime liquid-phase rearrangement products. Background Technology

[0002] Caprolactam is an important intermediate in the nylon industry chain. Currently, the mainstream production process for caprolactam involves first producing cyclohexanone from benzene, then reacting it with hydroxylamine to prepare cyclohexanone oxime, followed by Beckmann rearrangement using fuming sulfuric acid to generate a caprolactam-sulfuric acid mixture. This mixture is then neutralized and crystallized to produce a crude caprolactam solution containing ammonium sulfate, which is further purified in a refining unit. The crude caprolactam solution contains 60%-70% caprolactam, with the remainder consisting of impurities such as ammonium sulfate, water, cyclohexanone, benzene, toluene, and cyclohexanol. Current research focus in this field is on efficient purification methods for the crude caprolactam solution.

[0003] Researchers have already studied the refining process of crude caprolactam. For example, patent CN201620239506.2 reports a caprolactam refining device, which consists of an extraction tower, a refining tower, a hydrogenation reactor, a light weight removal tower, and a distillation unit, simplifying the process. Patent CN201711000196.4 reports a caprolactam refining method; the steps include extraction, hydrogen peroxide washing, back-extraction, and ion exchange, extending the lifespan of the ion exchange resin. Patent CN201621187626.9 reports a low-energy-consumption caprolactam refining device; compared to traditional caprolactam refining processes, it adds an alkali washing tower, an acid washing tower, and a heavy weight removal tower, while reducing water extraction and evaporation steps, thus reducing wastewater generation. However, due to limitations in the efficiency of the extraction unit, the refining effect of the above designs is relatively poor.

[0004] Furthermore, during the optimization of the refining process, the laboratory discovered that the efficient separation of caprolactam, water, and ammonium sulfate in the extraction step can effectively shorten the refining process and reduce the proportion of polymerization side reactions of caprolactam. The key to efficient separation in the extraction step lies in the design of the phase separator in the extraction tower. Existing patents have optimized the impeller structure to enhance mass transfer; for example, CN220758739U reports a highly efficient liquid dispersion device, but the mass transfer enhancement effect of this patent is still limited. The reason for this is that the above-mentioned improved extraction devices do not take into account strong mass transfer disturbances and multi-stage extraction. Therefore, further optimization of the extraction device structure is needed.

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

[0006] The purpose of this invention is to provide a perforated plate liquid phase separator for cyclohexanone oxime liquid-phase rearrangement products. This phase separator can enhance mass transfer and efficiently mix the feed liquid through the liquid guide tube in the special perforated plate phase separator. Secondly, the uniform distribution of multiple liquid distribution plates forms a phase separation space to achieve the purpose of multi-stage extraction, thereby realizing that a single tower can complete separation work such as traditional extraction, back-extraction and ion exchange.

[0007] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0008] This invention provides a perforated plate type liquid phase separator for liquid phase rearrangement products of cyclohexanone oxime. The perforated plate type liquid phase separator is set in the middle of the phase separation column for liquid phase separation. It includes a liquid distribution plate and a liquid guide pipe. The liquid guide pipe is composed of an interconnected support pipe and a phase separation structure. The liquid guide pipe is arranged perpendicular to the liquid distribution plate.

[0009] The perforated plate phase separator is equipped with a support device that holds it within the phase separation column. This support device also drives the phase separator to rotate at a speed of 0-400 rpm. Different rotation speeds can be selected based on the properties of the liquids to be separated; a lower rotation speed is chosen for high-viscosity liquids, and a higher speed for low-viscosity liquids. The perforated plate phase separator is positioned in the middle of the phase separation column, facilitating extraction or back-extraction of liquids with different properties. The perforated plate phase separator is positioned opposite the center of the phase separation column, ensuring easy rotation within the column without contacting the column walls, and facilitating assembly and disassembly; it also promotes more effective phase separation.

[0010] The orifice-type phase separator mainly consists of a distribution plate and conduits. The design of the distribution plate and conduits allows liquids of different properties to pass through, thereby achieving phase separation. The conduits are divided into heavy phase downcomer and light phase upcomer. The heavy phase downcomer is inverted and installed on the distribution plate, opposite to the light phase upcomer.

[0011] Preferably, as a further specific embodiment, the phase separation structure mainly consists of a diffusion region and a mixing region, wherein the diffusion region connects the mixing region and the support tube; the diffusion region has a frustum-shaped structure, and the portion connecting it to the mixing region is enlarged.

[0012] Preferably, as a further specific embodiment, the phase separation structure further includes a plurality of disturbance plates, wherein the disturbance plates are disc-shaped structures with a central opening, and are disposed on the mixing zone through the central opening.

[0013] The support tube of the liquid guide tube is connected to the diffusion zone, and the connection between the diffusion zone and the mixing zone is enlarged. The diffusion zone has a frustum-shaped structure with a gradually increasing diameter. On the one hand, the gradual increase in diameter can gradually slow down the flow rate of the liquid, allowing the liquid to slow down and enter the mixing zone in the diffusion zone, and under the action of the disturbance plate, it can undergo rapid and efficient phase separation. 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.

[0014] Multiple disturbance plates are installed in the mixing zone of the liquid guide tube. The disturbance plates can rotate under the action of the phase separation driving force to separate the liquid to be separated into phases, so that the extract and the liquid to be separated are fully separated and fully extracted.

[0015] Preferably, as a further specific embodiment, the liquid distribution plate is divided into an upper plate surface and a lower plate surface, and the liquid guiding pipes are evenly distributed in the upper plate surface and the lower plate surface.

[0016] Preferably, as a further specific embodiment, the mixing zone located on the upper plate and the nozzle of the mixing zone located on the lower plate are opposite to each other.

[0017] The two liquid phases are mixed at the outlet of the mixing zone. With the mixing zones facing each other, the feed moving from top to bottom and the extract moving from bottom to top can be fully mixed at the outlet of the mixing zone.

[0018] Preferably, as a further specific embodiment, the support tube penetrates the upper or lower plate surface, and the bottom of the support tube is flush with the surface of the liquid distribution plate.

[0019] In this invention, the distance between the upper and lower surfaces of the liquid distribution plate is 0.2-1.5 times the diameter of the phase separation tower. The distance between the upper and lower surfaces should not be too large or too small. If the distance between the upper and lower surfaces is too small, it may lead to incomplete phase separation. During the phase separation process, the low-density liquid moves upward under the action of the phase separation driving force. If the distance between the liquid distribution plates is too large, the low-density liquid may not be able to accurately enter the corresponding liquid guide pipe, resulting in losses.

[0020] The diameter of the liquid distribution plate is 0.5-0.98 times the diameter of the phase separation tower. In the perforated plate phase separator, the thickness of the upper and lower plates of all liquid distribution plates is equal, approximately 5mm-40mm. The diameter of the liquid distribution plate is smaller than the overall diameter of the phase separation tower, but larger than 0.5 times the tower diameter. This ensures that the perforated plate phase separator occupies a large area within the tower, preventing liquid erratic movement, further ensuring complete phase separation, and improving separation efficiency.

[0021] Each liquid guide tube's mixing zone vertically penetrates the upper or lower plate surface, and these tubes are evenly and vertically distributed within the distribution plate. Simultaneously, the support tubes within the liquid guide tubes are embedded in both the upper and lower plates. The embedding depth can be determined based on actual usage, but the liquid guide tubes must be sealed tightly against the contact surface of the upper or lower plate surface without gaps to ensure airtightness and minimize liquid loss during phase separation. Furthermore, the bottom of the support tube is flush with the upper or lower plate surface, without protrusions, facilitating liquid entry and improving phase separation efficiency. In addition, the parallel, one-to-one correspondence of the liquid guide tubes ensures that high-density liquids moving downwards and low-density liquids moving upwards accurately enter their respective tubes for the next stage of phase separation. This achieves multi-stage phase separation and extraction, thereby improving phase separation efficiency.

[0022] Preferably, as a further specific embodiment, the perforated plate phase separator is composed of 40-60 layers of liquid distribution plates, all of which are centered opposite each other and are equidistant from each other.

[0023] In this invention, a multi-stage liquid distribution plate is designed to match the height of the phase separation tower while maximizing the phase separation efficiency. Therefore, the number of stages of the liquid distribution plate is set to 40-60 layers, which can improve the phase separation efficiency within a limited height.

[0024] Preferably, as a further specific embodiment, the diffusion angle of the diffusion region is 10°-60°.

[0025] Preferably, as a further specific embodiment, the total area of ​​the support tube of the liquid guide tube is 20%-80% of the area of ​​the liquid distribution plate.

[0026] In practical applications, the number of liquid guide tubes can be selected according to the properties of the chosen liquid. However, the area occupied by the liquid guide tubes should not 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 practical applications, as many liquid guide tubes as possible can be set according to the properties of the liquid.

[0027] Preferably, as a further specific embodiment, the vertical height of the diffusion zone of the liquid guide tube is 0.3-1.5 times the vertical height of the support tube;

[0028] The vertical height of the mixing zone of the liquid guide tube is 0.3-1.5 times the vertical height of the support tube, and the diameter of the mixing zone is 1.2-4 times that of the support tube.

[0029] The vertical height of the diffusion zone is 0.3-1.5 times the vertical height of the support tube. When encountering liquids that are difficult to separate into phases and need to be mixed as much as possible, its vertical height is 1-1.5 times the vertical height of the support tube; while when the liquid is relatively easy to separate into phases, its vertical height is 0.3-1 times the vertical height of the support tube.

[0030] A diffusion zone is set between the mixing zone and the support pipe to diffuse the liquid; therefore, the diameter of the final mixing zone must be larger than the diameter of the support pipe. In actual installation, multiple factors need to be considered, including the size of the distribution plate, the properties of the liquid itself, and the liquid flow rate. Therefore, the diameter of the mixing zone is set to 1.2-4 times the diameter of the support pipe. This ensures that the liquid flows through the mixing zone at a moderate velocity and is fully mixed within it, while also allowing for a suitable size of the mixing zone. This allows for an increase in the number of guide pipes in the distribution plate without reducing the number of guide pipes due to an excessively large mixing zone.

[0031] 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.

[0032] The disturbance plates are set in the mixing area. Since the mixing area is a cylindrical structure, multiple disturbance plates can be set. During the setting process, the distance between them needs to be controlled to improve the mixing efficiency.

[0033] The distance between the upper and lower surfaces of the liquid distribution plate is 0.2-1.5 times the diameter of the phase separation tower.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] (1) The present invention can enhance mass transfer and efficiently mix the liquid through a specially designed liquid guide tube; each liquid distribution plate space forms a uniform phase separation space to achieve the purpose of multi-stage extraction, so that a single extraction tower can complete the separation work such as extraction, back extraction and ion exchange; at the same time, it can improve the mixing efficiency and mass transfer performance of the liquid, and has the advantages of occupying less space, convenient installation and easy level adjustment.

[0036] (2) It effectively improves the efficiency of the extraction device and significantly reduces equipment and operating costs. In addition, it is known that sulfides in the crude caprolactam-extractant mixture have a significant impact on the conversion rate and selectivity of the subsequent ammoniation reaction. Therefore, the above advantages make this invention highly economical in the field of nylon new material preparation. At the same time, it can effectively shorten the process flow and has greater application significance. Attached Figure Description

[0037] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0038] Figure 1 : Simplified diagram of a perforated plate liquid phase separator;

[0039] Figure 2 : Structure diagram of the liquid guide tube in a perforated disc liquid phase separator;

[0040] Figure 3 The location of the orifice-type liquid phase separator in the phase separation tower.

[0041] The markings in the attached figure are as follows:

[0042] 1. Liquid distribution plate - lower plate surface; 2. Diffusion zone; 3. Mixing zone; 4. Disturbance plate; 5. Support tube;

[0043] 6. Liquid guide tube - heavy phase downcomer; 7. Liquid guide tube - light phase upcomer; 8. Liquid distribution plate - upper plate surface;

[0044] 10. Raw material import; 11. Extractant import; 12. Waste liquid export; 13. Orifice plate phase separator. Detailed Implementation

[0045] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0046] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0047] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0048] To more clearly illustrate the technical solutions in this invention, specific embodiments are described below.

[0049] Example 1

[0050] The structure of a perforated disk liquid phase separator for cyclohexanone oxime liquid-phase rearrangement products, such as Figure 1 and Figure 2 The diagram shows a simplified representation of a perforated plate liquid phase separator and a structural diagram of the liquid guide pipe within it. As can be seen, a perforated plate liquid phase separator consists of multiple layers of distribution plates. Each distribution plate comprises a lower distribution plate surface 1 and an upper distribution plate surface 8. The lower surface serves as the upper surface of another distribution plate, and this alternation forms the hierarchical structure of the perforated plate phase separator 13. The perforated plate phase separator has 40-60 stages. The distance between the lower distribution plate surface 1 and the upper distribution plate surface 8 is 0.2-1.5 times the diameter of the phase separator tower.

[0051] Each liquid distribution plate is equipped with multiple liquid guide tubes, which are further divided into liquid guide tube-heavy phase downcomer 6 and liquid guide tube-light phase upcomer 7. Support tube 1 vertically penetrates the upper or lower surface of the liquid distribution plate. The liquid guide tubes are evenly distributed on the upper or lower surface of the liquid distribution plate, and each liquid guide tube is parallel to the others. The liquid guide tube-heavy phase downcomer 6 and the liquid guide tube-light phase upcomer 7 correspond one-to-one, and the liquid guide tube-light phase upcomer 7 is placed upside down in the surface of the liquid distribution plate. The bottom of the support tube 5 is flush with the upper or lower surface of the liquid distribution plate (i.e., without protrusion). The total area of ​​the support tube 5 accounts for 20%-80% of the total area of ​​the liquid distribution plate.

[0052] from Figure 2The structure of the liquid guiding tube is visible. It 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. The diffusion angle of the diffusion zone 2 is 10°-60°. The connection between the diffusion zone 2 and the mixing zone 3 is enlarged, and the diffusion zone 2 has a frustum-shaped structure. The diameter of the mixing zone 3 is equal to the enlarged diameter of the diffusion zone 2, and the mixing zone 3 is cylindrical. A disturbance plate 4 is installed in the mixing zone 3. The disturbance plate 4 is cylindrical, and its vertical height 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. Furthermore, the vertical height of the mixing zone 3 is 0.3-1.5 times the vertical height of the support tube 5.

[0053] from Figure 3 As can be seen, the perforated liquid phase separator 10 is located in the phase separation tower, the perforated liquid phase separator 13 is located in the middle of the phase separation tower 9, the raw material inlet 10 is located at the upper part of the perforated liquid phase separator 13, the extractant inlet 8 is located at the lower part of the perforated liquid phase separator 13, and the bottom of the phase separation tower 9 is also provided with a waste liquid outlet 12.

[0054] Workflow:

[0055] Select the raw material and extractant to be separated. The raw material is introduced into the phase separation tower 9 through the raw material inlet 10, while the extractant enters through the extractant inlet 11. The extractant moves upwards from the liquid guide pipe to the light phase riser pipe 7 and then from the liquid distribution plate to the lower plate surface 1 under the action of the phase separation driving force. The raw material to be separated moves downwards from the liquid guide pipe to the heavy phase fallr pipe 6 and then from the liquid distribution plate to the upper plate surface 8. When the two raw materials first enter the perforated plate phase separator, they pass through the corresponding support pipe 5, diffusion zone 2, and mixing zone 3, respectively.

[0056] The two liquids continuously move until they first come into contact in the gap between the liquid guide pipe-light phase rising pipe 7 and the liquid guide pipe-heavy phase falling pipe 6, where they continue to mix. The mixture then enters the mixing zone 3 of the liquid guide pipe, where the agitator plate 4 rotates continuously, causing the first phase separation. After the first phase separation, the mixture continues to move downwards, repeatedly interacting with the extractant moving upwards, undergoing extraction until the reaction is complete. The waste liquid is discharged from the waste liquid outlet 12 at the bottom of the phase separation column 9, and the extracted raw liquid flows out from the top of the phase separation column 9 into the distillation column.

[0057] Example 2

[0058] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the liquid distribution trays is 0.2 times the column diameter; the diameter of the liquid distribution tray is 0.95 times the column diameter; the thickness of the liquid distribution tray is 10 mm; the diameter of the rotating rod of the liquid distribution tray is 30 mm; the rotation speed of the liquid distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of the extractant to the feed is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.50% and an ammonium sulfate content of 30 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.20%.

[0059] Example 3

[0060] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the liquid distribution trays is 1.5 times the column diameter; the diameter of the liquid distribution tray is 0.95 times the column diameter; the thickness of the liquid distribution tray is 10 mm; the diameter of the rotating rod of the liquid distribution tray is 30 mm; the rotation speed of the liquid distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of the extractant to the feed is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.56% and an ammonium sulfate content of 100 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.30%.

[0061] Example 4

[0062] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the distribution trays is 0.2 times the column diameter; the diameter of the distribution tray is 0.5 times the column diameter; the thickness of the distribution tray is 10 mm; the diameter of the distribution tray rotating rod is 30 mm; the rotation speed of the distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of extractant to feedstock is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.56% and an ammonium sulfate content of 50 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.26%.

[0063] Example 5

[0064] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the distribution trays is 0.2 times the column diameter; the diameter of the distribution tray is 0.95 times the column diameter; the thickness of the distribution tray is 30 mm; the diameter of the distribution tray rotating rod is 30 mm; the rotation speed of the distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of the extractant to the feed is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.60% and an ammonium sulfate content of 50 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.31%.

[0065] Example 6

[0066] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction tower has a diameter of 1 m; the spacing between the distribution trays is 0.2 times the tower diameter; the diameter of the distribution tray is 0.95 times the tower diameter; the thickness of the distribution tray is 10 mm; the diameter of the distribution tray rotating rod is 30 mm; the rotation speed of the distribution tray is 60 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of the extractant to the feed is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.58% and an ammonium sulfate content of 50 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.31%.

[0067] Example 7

[0068] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the distribution trays is 0.2 times the column diameter; the diameter of the distribution tray is 0.95 times the column diameter; the thickness of the distribution tray is 10 mm; the diameter of the distribution tray rotating rod is 30 mm; the rotation speed of the distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 40% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of extractant to feedstock is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.62% and an ammonium sulfate content of 100 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.25%.

[0069] Example 8

[0070] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the liquid distribution trays is 0.2 times the column diameter; the diameter of the liquid distribution tray is 0.95 times the column diameter; the thickness of the liquid distribution tray is 10 mm; the diameter of the rotating rod of the liquid distribution tray is 30 mm; the rotation speed of the liquid distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of the extractant to the feed is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.61% and an ammonium sulfate content of 80 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.26%.

[0071] Example 9

[0072] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the distribution trays is 0.2 times the column diameter; the diameter of the distribution tray is 0.95 times the column diameter; the thickness of the distribution tray is 10 mm; the diameter of the distribution tray rotating rod is 30 mm; the rotation speed of the distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 1 times the vertical height of the support tube, and the diffusion angle is 60 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.4 times the diameter of the mixing zone, the width is 0.05 times the diameter of the mixing zone, and the height is 0.8 times the vertical height of the mixing zone; the volumetric flow rate ratio of the extractant to the feed is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.59% and an ammonium sulfate content of 70 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.24%.

[0073] Example 10

[0074] The caprolactam solution containing ammonium sulfate obtained from the cyclohexanone oxime rearrangement process was used as the feed liquid (caprolactam mass fraction was 80%, water mass fraction was 19%, and ammonium sulfate mass fraction was 0.6%). Benzene was used as the extractant, and an extraction tower equipped with a special perforated plate liquid phase separator was used as the operating equipment with 40 layers of liquid distribution plates. The extraction column has a diameter of 1 m; the spacing between the liquid distribution trays is 0.2 times the column diameter; the diameter of the liquid distribution tray is 0.95 times the column diameter; the thickness of the liquid distribution tray is 10 mm; the diameter of the rotating rod of the liquid distribution tray is 30 mm; the rotation speed of the liquid distribution tray is 400 rpm; the total horizontal cross-sectional area of ​​the liquid guide tube is 80% of the tray area; the vertical height of the support tube 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 zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diffusion angle is 30 degrees; the vertical height of the mixing zone of the liquid guide tube is 0.5 times the vertical height of the support tube, and the diameter is 2 times the diameter of the support tube; the length of the disturbance plate is 0.1 times the diameter of the mixing zone, the width is 0.1 times the diameter of the mixing zone, and the height is 0.2 times the vertical height of the mixing zone; the volumetric flow rate ratio of the extractant to the feed is 10. The top of the column yields a caprolactam-benzene solution with a water content of 0.59% and an ammonium sulfate content of 10 ppm; the bottom of the column yields an aqueous solution containing ammonium sulfate with a COD of 0.26%.

[0075] Example 11

[0076] The specific implementation method is consistent with Example 2, except that the number of layers of the liquid distribution plate is set to 60 layers, and the final aqueous solution containing ammonium sulfate has a COD of 0.20%.

[0077] Comparative Example 1

[0078] The specific implementation method is consistent with Example 2, except that the structure of the liquid guide tube is changed and a non-partitioned cylindrical liquid guide tube is used, and the final measured COD is 0.55%.

[0079] Comparative Example 2

[0080] The specific implementation method is consistent with Example 2, except that the liquid guide tube is set at an angle to the liquid distribution plate, and the final measured COD is 0.51%.

[0081] As can be seen from Examples 2 and Comparative Examples 1-2, the structure of the liquid distribution plate, the conduit, and the liquid guide tube itself is very important in this invention. The liquid guide tube is divided into sections, each with different functions. The phase separation structure for phase separation can effectively improve the working capacity of the perforated plate liquid distribution phase separator, effectively reduce the COD content in the finished product, and improve working efficiency, while the support tube can provide effective support for it.

[0082] The liquid guide tube is set perpendicular to the liquid distribution plate, which allows the liquid to be separated from top to bottom to be fully mixed with the extract liquid from bottom to top, effectively improving the reaction rate and making it more practically significant.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions 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 hole-plate liquid phase separator for cyclohexanone oxime liquid phase rearrangement product, characterized in that, The hole disc liquid phase separator is arranged in the middle of the phase separation tower for liquid phase separation, and comprises a liquid distribution disc and a liquid guide pipe which is composed of a support pipe and a phase separation structure connected with each other; the liquid guide pipe is arranged vertically to the liquid distribution disc; The phase separation structure mainly comprises a diffusion zone and a mixing zone, and the diffusion zone is connected with the mixing zone and the support pipe; the diffusion zone is in a circular truncated cone structure, and the part connected with the mixing zone is expanded in diameter; The phase separation structure further comprises a plurality of disturbance plates which are in a circular disc structure with a center hole and are arranged on the mixing zone through the center hole; The liquid distribution disc is divided into an upper disc surface and a lower disc surface, and the liquid guide pipes are uniformly distributed in the upper disc surface and the lower disc surface; The pipe openings of the liquid guide pipes on the upper disc surface and the liquid guide pipes on the lower disc surface are one-to-one corresponding.

2. The well-plate liquid phase separator for cyclohexanone oxime liquid phase rearrangement product according to claim 1, characterized in that, The support pipe penetrates the upper disc surface or the lower disc surface, and the bottom of the support pipe is flush with the surface of the liquid distribution disc.

3. The well-plate liquid phase separator for cyclohexanone oxime liquid phase rearrangement product according to claim 1, characterized in that, The number of layers of the liquid distribution disc is 40-60, each layer of the liquid distribution disc is centrally opposite, and the upper disc surface and the lower disc surface of each liquid distribution disc are equidistantly distributed.

4. The well-plate liquid phase separator for cyclohexanone oxime liquid phase rearrangement product according to claim 1, characterized in that, The diffusion angle of the diffusion zone is 10°-60°.

5. The well-plate liquid phase separator for cyclohexanone oxime liquid phase rearrangement product according to claim 1, characterized in that, The total area of the support pipe in the liquid guide pipe is 20%-80% of the area of the liquid distribution disc.

6. The well-plate liquid phase separator for cyclohexanone oxime liquid phase rearrangement product according to claim 1, characterized in that, The vertical height of the diffusion zone of the liquid guide pipe is 0.3-1.5 times of the vertical height of the support pipe; The vertical height of the mixing zone of the liquid guide pipe is 0.3-1.5 times of the vertical height of the support pipe, and the diameter of the mixing zone is 1.2-4 times of the support pipe.

Images