Caprolactam ion exchange dehydration regeneration system

Abstract

The embodiment of the utility model provides a caprolactam ion exchange dehydration regeneration system, and belongs to the technical field of chemical production. The dehydration regeneration system comprises first to sixth ion exchange towers, a discharge port of the first ion exchange tower is connected with a feed port of a second ion exchange tower through a first pipeline, and a discharge port of the second ion exchange tower is connected with a feed port of a third ion exchange tower through a second pipeline; a discharge port of the third ion exchange tower is connected with a feed port of the fourth ion exchange tower through a third pipeline, and a discharge port of the fourth ion exchange tower is connected with a feed port of the fifth ion exchange tower through a fourth pipeline; the part, located between the two first switch valves, of the first pipeline is connected with the part, located between the two second switch valves, of the third pipeline through a first series pipeline. The part, located between the two switch valves, of the second pipeline is connected with the part, located between the two switch valves, of the fourth pipeline through a second series pipeline. And the six ion exchange towers are respectively connected with dehydration pipelines.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of chemical production, especially relates to a caprolactam ion exchange dewatering regeneration system. BACKGROUND

[0002] Caprolactam is one of important organic chemical raw materials, and its main use is to generate polyamide chip (usually called nylon-6 chip, or chinlon-6 chip) through polymerization, which can be further processed into chinlon fiber, engineering plastic and plastic film.

[0003] Ion exchange action is needed to remove anion and cation impurities in caprolactam aqueous solution in the caprolactam refining section, but when the ion exchange tower reaches saturation, regeneration is needed.

[0004] The existing caprolactam refining section process is to set two sets of ion exchange towers, the first set of ion exchange towers includes tower 1, tower 2 and tower 3, the first set of ion exchange towers includes tower 4, tower 5 and tower 6. When it is detected that the caprolactam water index discharged by one of the two sets of ion exchange towers deteriorates, it may be that one of the ion exchange towers in this set of ion exchange towers is saturated, so the entire ion exchange (three towers) needs to be regenerated together, and the unsaturated ion exchange tower cannot be used continuously and needs to be regenerated together. This is because the three towers are connected in series, that is, the saturated ion exchange tower cannot be dewatered alone. In this way, the ion exchange system cannot fully utilize the ion exchange tower exchange capacity, increases the ion exchange regeneration frequency, and increases the ion exchange operation cost. SUMMARY

[0005] In view of the above problems existing in the prior art, the purpose of the embodiments of the utility model is to provide a caprolactam ion exchange dewatering regeneration system. The dewatering regeneration system can realize arbitrary combination of six ion exchange towers, maximize the utilization of ion exchange tower capacity, reduce the ion exchange regeneration frequency, and reduce the ion exchange operation cost.

[0006] The technical scheme adopted by the embodiments of the utility model is:

[0007] A caprolactam ion exchange dewatering regeneration system, comprising:

[0008] The first set of ion exchange towers includes a first ion exchange tower, a second ion exchange tower and a third ion exchange tower, the feed inlet of the first ion exchange tower is connected with a first caprolactam water pipeline, the discharge outlet of the first ion exchange tower is connected with the feed inlet of the second ion exchange tower through a first pipeline, the discharge outlet of the second ion exchange tower is connected with the feed inlet of the third ion exchange tower through a second pipeline, and two first on-off valves are respectively arranged on the first pipeline and the second pipeline;

[0009] The second set of separating and mixing towers comprises a third separating and mixing tower, a fourth separating and mixing tower and a fifth separating and mixing tower, the feed inlet of the third separating and mixing tower is connected with the second caproamide water pipeline, the discharge outlet of the third separating and mixing tower is connected with the feed inlet of the fourth separating and mixing tower through a third pipeline, the discharge outlet of the fourth separating and mixing tower is connected with the feed inlet of the fifth separating and mixing tower through a fourth pipeline, and two second switch valves are arranged on the third pipeline and the fourth pipeline respectively;

[0010] The serial pipeline set comprises a first serial pipeline and a second serial pipeline, one end of the first serial pipeline is connected with a part of the first pipeline between the two first switch valves, the other end of the first serial pipeline is connected with a part of the third pipeline between the two second switch valves, one end of the second serial pipeline is connected with a part of the second pipeline between the two first switch valves, and the other end of the second serial pipeline is connected with a part of the fourth pipeline between the two second switch valves;

[0011] The drainage pipeline is connected with the first separating and mixing tower, the second separating and mixing tower, the third separating and mixing tower, the fourth separating and mixing tower, the fifth separating and mixing tower and the sixth separating and mixing tower respectively.

[0012] Further, the caprolactam separating and dehydrating regeneration system further comprises a neutralization tank, and the end of the drainage pipeline is connected with the neutralization tank.

[0013] Further, the neutralization tank comprises a dilute tank and a concentrated tank, the end of the drainage pipeline is divided into a first pipeline connected with the dilute tank and a second pipeline connected with the concentrated tank, and switch valves are arranged on the first pipeline and the second pipeline respectively.

[0014] Further, the neutralization tank is located below each separating and mixing tower, and the drainage pipeline is connected with the bottom of each separating and mixing tower.

[0015] Further, the first caproamide water pipeline and the second caproamide water pipeline are the same pipeline.

[0016] Further, the caprolactam separating and dehydrating regeneration system further comprises;

[0017] The nitrogen pipeline is connected with the first separating and mixing tower, the second separating and mixing tower, the third separating and mixing tower, the fourth separating and mixing tower, the fifth separating and mixing tower and the sixth separating and mixing tower respectively, so as to inject nitrogen into each separating and mixing tower.

[0018] Further, the caprolactam separating and dehydrating regeneration system further comprises a buffer tank, and the discharge outlet of the third separating and mixing tower and the discharge outlet of the sixth separating and mixing tower are connected with the buffer tank respectively.

[0019] Compared with the prior art, the beneficial effects of the embodiments of the utility model lie in:

[0020] The first pipeline in the caprolactam ion exchange dewatering regeneration system of the application is connected with the third pipeline through a first series pipeline, and the second pipeline is connected with the fourth pipeline through a second series pipeline, so that any combination of six ion exchange towers can be realized, and the six ion exchange towers are respectively connected with dewatering pipelines, so that any single-tower dewatering can be realized, thereby reducing ion exchange regeneration frequency and reducing ion exchange operation cost.

[0021] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory in nature and are not intended to limit the present application.

[0022] The foregoing general description and the following detailed description of various implementations or examples of the technology described in the present application are not a comprehensive disclosure of the entire scope or all features of the disclosed technology. BRIEF DESCRIPTION OF DRAWINGS

[0023] In the drawings, which are not necessarily drawn to scale, like numerals can describe similar components in different views. The drawings are generally intended to illustrate various embodiments of the application and are not intended to limit the application, nor the explanation of the application, together with the specification serving to explain the embodiments of the application. Where appropriate, the same reference numbers are used throughout the drawings to refer to the same or like parts.

[0024] Figure 1 A structure schematic view of a caprolactam ion exchange dewatering regeneration system of the present application embodiment is provided for the material;

[0025] In the drawings: 1, first ion exchange tower; 2, second ion exchange tower; 3, third ion exchange tower; 4, fourth ion exchange tower; 5, fifth ion exchange tower; 6, sixth ion exchange tower; 7, first pipeline; 8, second pipeline; 9, discharge pipeline; 10, third pipeline; 11, fourth pipeline; 12, first series pipeline; 13, second series pipeline; 14, first on-off valve; 15, second on-off valve; 16, drainage pipeline; 17, first pipeline; 18, second pipeline; 19, first switch valve; 20, second switch valve; 21, neutralization tank; 210, dilute tank; 211, concentrated tank; 22, first caprolactam water pipeline; 23, second caprolactam water pipeline; 24, buffer tank; 25, dewatering valve. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present application embodiment clearer, the technical scheme of the present application embodiment will be described clearly and completely below in combination with the drawings of the present application embodiment. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the described embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0027] Unless otherwise defined, technical terms or scientific terms used in the present application shall have the ordinary meaning as understood by a person of ordinary skill in the art to which the present application pertains. The terms "first", "second", and similar terms are used herein merely to distinguish one element from another, and are not intended to imply any order or importance. The terms "include", "comprise", and similar terms are used herein to indicate the presence of the elements or objects listed after the terms, and are not intended to preclude the presence of other elements or objects. The terms "connected" or "coupled" are used herein to indicate any connection or coupling between two elements, which can be direct or indirect, and can include electrical, mechanical, or other types of connection or coupling. The terms "upper", "lower", "left", "right", and similar terms are used herein merely to indicate relative positions, and can change when the absolute positions of the described objects change. In order to keep the following description of the embodiments of the present application clear and concise, detailed descriptions of known functions and known components are omitted.

[0028] The embodiment provides a caprolactam ion exchange dewatering regeneration system, which comprises a first set of ion exchange towers, a second set of ion exchange towers, a series pipeline group and a drain pipeline 16.

[0029] The first set of ion exchange towers comprises a first ion exchange tower 1, a second ion exchange tower 2 and a third ion exchange tower 3. The feed inlet of the first ion exchange tower 1 is connected with a first caprolactam water pipeline 22, the outlet of the first ion exchange tower 1 is connected with the feed inlet of the second ion exchange tower 2 through a first pipeline 7, and the outlet of the second ion exchange tower 2 is connected with the feed inlet of the third ion exchange tower 3 through a second pipeline 8. Two first switch valves 14 are arranged on the first pipeline 7 and the second pipeline 8 respectively.

[0030] The second set of ion exchange towers comprises a fourth ion exchange tower 4, a fifth ion exchange tower 5 and a sixth ion exchange tower 6. The feed inlet of the fourth ion exchange tower 4 is connected with a second caprolactam water pipeline 23, and the outlet of the fourth ion exchange tower 4 is connected with the feed inlet of the fifth ion exchange tower 5 through a third pipeline 10. The outlet of the fifth ion exchange tower 5 is connected with the feed inlet of the sixth ion exchange tower 6 through a fourth pipeline 11, and two second switch valves 15 are arranged on the third pipeline 10 and the fourth pipeline 11 respectively.

[0031] The series pipeline group comprises a first series pipeline 12 and a second series pipeline 13. One end of the first series pipeline 12 is connected with a part of the first pipeline 7 between the two first switch valves 14, and the other end is connected with a part of the third pipeline 10 between the two second switch valves 15.

[0032] One end of the second series pipeline 13 is connected with a part of the second pipeline 8 between the two first switch valves 14, and the other end of the second series pipeline 13 is connected with a part of the fourth pipeline 11 between the two second switch valves 15.

[0033] The drain pipeline 16 is connected with the first ion exchange tower 1, the second ion exchange tower 2, the third ion exchange tower 3, the fourth ion exchange tower 4, the fifth ion exchange tower 5 and the sixth ion exchange tower 6 respectively, and the drain pipeline 16 realizes the individual dehydration of the six ion exchange towers.

[0034] The first pipeline 7 and the third pipeline 10 are connected through the first series pipeline 12, and the second pipeline 8 and the fourth pipeline 11 are connected through the second series pipeline 13 in the caprolactam ion exchange dehydration regeneration system of the embodiment, so that any combination of the six ion exchange towers can be realized, and the six ion exchange towers are connected with the dehydration pipelines respectively, so that the individual dehydration of any tower can be realized, thereby reducing the ion exchange regeneration frequency and the ion exchange operation cost. During the regeneration, the dehydration rate is improved, the ion exchange regeneration time is shortened, the nitrogen consumption is reduced, and the cost is saved.

[0035] For example, by switching the switch valves on the four communication pipelines, the first ion exchange tower 1, the second ion exchange tower 2 and the third ion exchange tower 3 can be combined, the first ion exchange tower 1, the fifth ion exchange tower 5 and the third ion exchange tower 3 can be combined, the first ion exchange tower 1, the second ion exchange tower 2 and the sixth ion exchange tower 6 can be combined, the fourth ion exchange tower 4, the fifth ion exchange tower 5 and the sixth ion exchange tower 6 can be combined, the fourth ion exchange tower 4, the second ion exchange tower 2 and the sixth ion exchange tower 6 can be combined, the fourth ion exchange tower 4, the fifth ion exchange tower 5 and the third ion exchange tower 3 can be combined, and the fourth ion exchange tower 4, the second ion exchange tower 2 and the third ion exchange tower 3 can be combined.

[0036] It should be noted that the dehydration valves 25 are arranged at the connection positions of the six ion exchange towers and the dehydration pipelines in the embodiment. When the dehydration of a certain ion exchange tower is needed, the corresponding dehydration valve 25 is opened, so that the dehydration of any single tower is realized, the dehydration efficiency is improved, and the regeneration time is shortened.

[0037] In some embodiments, the caprolactam ion exchange dehydration regeneration system further includes a neutralization tank 21, and the end of the drain pipeline 16 is connected with the neutralization tank 21. The wastewater generated by the six ion exchange towers can be discharged into the neutralization tank 21 for recovery.

[0038] Preferably, in some embodiments, the neutralization tank 21 includes two parts of a dilute tank 210 and a concentrated tank 211. The end of the drain pipeline 16 is divided into a first pipeline 17 connected with the dilute tank 210 and a second pipeline 18 connected with the concentrated tank 211. The first pipeline 17 is provided with a first switch valve 19, and the second pipeline 18 is provided with a second switch valve 20.

[0039] In this way, before the wastewater generated by the six ion exchange towers is discharged into the neutralization tank 21, it can be determined according to the wastewater index whether it is appropriate to be discharged into the dilute tank 210 or the concentrated tank 211, so that the discharge of the ion exchange wastewater can be switched arbitrarily. When the wastewater is discharged into the dilute tank 210, the first switch valve 19 is opened and the second switch valve 20 is closed; when the wastewater is discharged into the concentrated tank 211, the second switch valve 20 is opened and the first switch valve 19 is closed.

[0040] In some embodiments, a neutralization tank 21 is located below each of the six ion exchange towers, and a drain line 16 is connected to the bottom of each of the six ion exchange towers. In this way, the wastewater can flow down by its own gravity and be discharged into the neutralization tank 21, thereby reducing the amount of nitrogen gas required for dewatering each tower, or achieving dewatering of any ion exchange tower without nitrogen gas, reducing material consumption and saving production costs.

[0041] In some embodiments, the first caprolactam water line 22 connected to the first ion exchange tower 1 and the second caprolactam water line 23 connected to the fourth ion exchange tower 4 are the same line.

[0042] Further, in some embodiments, the caprolactam ion exchange dewatering and regeneration system further comprises a nitrogen gas line (not shown in the figure). The nitrogen gas line is connected to the first ion exchange tower 1, the second ion exchange tower 2, the third ion exchange tower 3, the fourth ion exchange tower 4, the fifth ion exchange tower 5 and the sixth ion exchange tower 6, respectively, for injecting nitrogen gas into each ion exchange tower to dewater the resin in each ion exchange tower. Each ion exchange tower is provided with a corresponding exhaust pipe, and the nitrogen gas entering the ion exchange tower can be discharged through the exhaust pipe.

[0043] In some embodiments, the caprolactam ion exchange dewatering and regeneration system further comprises a buffer tank 24, and the discharge outlet of the third ion exchange tower 3 and the discharge outlet of the sixth ion exchange tower 6 are connected to the buffer tank 24 through a discharge line 9, respectively. The caprolactam aqueous solution in the first set of ion exchange towers and the caprolactam aqueous solution in the second ion exchange tower 2 are finally discharged into the buffer tank 24 through the discharge line 9.

[0044] The above description is intended to be illustrative and not restrictive, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present disclosure. Moreover, the above examples (or one or more aspects thereof) can be used in combination with each other, and these embodiments can be combined with each other in various combinations or arrangements.

Claims

1. A caprolactam ion exchange dehydrating regeneration system, characterized by, The application relates to a caprolactam ion exchange dewatering regeneration system. The first set of ion exchange towers comprises a first ion exchange tower, a second ion exchange tower and a third ion exchange tower, the feed inlet of the first ion exchange tower is connected with a first caprolactam water pipeline, the feed outlet of the first ion exchange tower is connected with the feed inlet of the second ion exchange tower through a first pipeline, the feed outlet of the second ion exchange tower is connected with the feed inlet of the third ion exchange tower through a second pipeline, two first switch valves are arranged on the first pipeline and the second pipeline respectively; The second set of ion exchange towers comprises a fourth ion exchange tower, a fifth ion exchange tower and a sixth ion exchange tower, the feed inlet of the fourth ion exchange tower is connected with a second caprolactam water pipeline, the feed outlet of the fourth ion exchange tower is connected with the feed inlet of the fifth ion exchange tower through a third pipeline, the feed outlet of the fifth ion exchange tower is connected with the feed inlet of the sixth ion exchange tower through a fourth pipeline, two second switch valves are arranged on the third pipeline and the fourth pipeline respectively; The series pipeline group comprises a first series pipeline and a second series pipeline, one end of the first series pipeline is connected with a part of the first pipeline between the two first switch valves, the other end of the first series pipeline is connected with a part of the third pipeline between the two second switch valves, one end of the second series pipeline is connected with a part of the second pipeline between the two first switch valves, the other end of the second series pipeline is connected with a part of the fourth pipeline between the two second switch valves; The drain pipeline is connected with the first ion exchange tower, the second ion exchange tower, the third ion exchange tower, the fourth ion exchange tower, the fifth ion exchange tower and the sixth ion exchange tower respectively.

2. A caprolactam ion exchange dewatering regeneration system as claimed in claim 1, characterized in that, The caprolactam ion exchange dewatering regeneration system further comprises a neutralization tank, and the end of the drain pipeline is connected with the neutralization tank.

3. A caprolactam ion exchange dewatering regeneration system as claimed in claim 2, characterized in that, The neutralization tank comprises a dilute tank and a concentrated tank, the end of the drain pipeline is divided into a first pipeline connected with the dilute tank and a second pipeline connected with the concentrated tank, and switch valves are arranged on the first pipeline and the second pipeline respectively.

4. A caprolactam ion exchange dewatering regeneration system as claimed in claim 2, characterized in that, The neutralization tank is located below each ion exchange tower, and the drain pipeline is connected with the bottom of each ion exchange tower.

5. A caprolactam ion exchange dewatering regeneration system as claimed in claim 1, characterized in that, The first caprolactam water pipeline and the second caprolactam water pipeline are the same pipeline.

6. A caprolactam ion exchange dewatering regeneration system as claimed in claim 1, characterized in that, The caprolactam ion exchange dewatering regeneration system further comprises; A nitrogen pipeline is connected with the first ion exchange tower, the second ion exchange tower, the third ion exchange tower, the fourth ion exchange tower, the fifth ion exchange tower and the sixth ion exchange tower respectively, so as to inject nitrogen into each ion exchange tower.

7. A caprolactam ion exchange dewatering regeneration system as claimed in claim 1, wherein, The caprolactam ion exchange dewatering regeneration system further comprises a buffer tank, and the feed outlet of the third ion exchange tower and the feed outlet of the sixth ion exchange tower are connected with the buffer tank respectively.

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