Isobutyraldehyde separation and purification system

Abstract

The utility model relates to an isobutyraldehyde separation and purification system which comprises an n-isobutyraldehyde separation tower, an isobutyraldehyde qualified product tank, a mixed butyraldehyde tank, an isobutyraldehyde refining tower and the like, a side-draw pipeline at the upper part of the n-isobutyraldehyde separation tower is connected with the mixed butyraldehyde tank, and the mixed butyraldehyde tank is connected with a pump inlet of the mixed butyraldehyde tank; an outlet pipeline of the mixed butyraldehyde pump is connected with a feeding hole of the isobutyraldehyde refining tower; a gas phase pipeline at the top of the isobutyraldehyde refining tower is connected with the cooler, a lower liquid pipeline of the cooler is connected with the top of the reflux tank, a lower liquid pipeline of the reflux tank is connected with an inlet of the reflux pump, one end of an outlet pipeline of the reflux pump is connected with an isobutyraldehyde qualified product tank, and the other end of the outlet pipeline of the reflux pump is connected with a reflux pipeline of the isobutyraldehyde refining tower. And a discharging pipeline of the tower kettle pump leads to a feeding pipeline of the n-isobutyraldehyde separation tower. According to the n-isobutyraldehyde separation tower, the problem of incomplete separation of the existing n-isobutyraldehyde separation tower is solved, mixed aldehyde containing 80% of isobutyraldehyde extracted from the original tower top is separated into high-quality products containing 99.7% of isobutyraldehyde, and the investment is saved.

Description

Technical Field

[0001] The utility model relates to a system in the field of chemical industry in which materials with similar boiling points are difficult to separate, in particular to a system for separating and purifying normal butyraldehyde and isobutyraldehyde. Background Art

[0002] There are two production processes for butyl octanol. One is the croton condensation hydrogenation method using acetaldehyde as raw material, and the other is the low-pressure carbonyl synthesis method using propylene and synthesis gas as raw materials. This method is one of the most advanced technologies in the world today. At present, 70% of the world's butyl octanol is produced by the propylene method. It uses propylene and synthesis gas as raw materials to produce crude butyraldehyde through low-pressure carbonyl synthesis, and then obtains butyl octanol through butyraldehyde treatment, condensation, and hydrogenation reactions. The separation of normal and isobutyraldehyde is an important unit in the butyraldehyde processing system. Since the boiling points of normal and isobutyraldehyde differ by 11°C and are close to each other, separation is more difficult. Therefore, the distillation tower for separating normal and isobutyraldehyde generally requires a high tower, a large tower diameter, and many trays, resulting in insufficient processing capacity of the distillation tower for separating normal and isobutyraldehyde. In many cases, the normal and isobutyraldehyde separation unit is the bottleneck of the entire butyraldehyde production system.

[0003] In the prior art, a distillation tower is used to separate butyraldehyde. The tower is extremely high, has a large diameter and many plates. The tower height and diameter have high requirements on the local geographical conditions and the foundation of the distillation tower, and the investment cost is also relatively high; the large number of plates increases the difficulty of system shutdown and maintenance; the high tower height, large tower diameter and large number of plates of the distillation tower also increase the daily operating costs. Utility Model Content

[0004] In view of this, the utility model provides a set of isobutyraldehyde separation and purification equipment, the purpose of which is to solve the existing bottleneck of butyraldehyde production, realize the purification of isobutyraldehyde, and effectively solve the problems in the background technology.

[0005] In order to achieve the above-mentioned purpose, the technical scheme of the utility model is implemented as follows: an isobutyraldehyde separation and purification system, comprising a positive isobutyraldehyde separation tower, an isobutyraldehyde qualified product tank, and also comprising a mixed butyraldehyde tank 1, a mixed butyraldehyde tank pump 7, an isobutyraldehyde refining tower 9, a cooler 14, a reflux tank 16, a reflux pump 21, and a tower bottom pump 23, wherein the upper side line extraction pipeline of the positive isobutyraldehyde separation tower is connected to the mixed butyraldehyde tank 1 through a mixed butyraldehyde tank feed pipeline 2, and the working pressure of the mixed butyraldehyde tank 1 is 0-20KPa, and the mixed butyraldehyde tank 1 is connected to the inlet of the mixed butyraldehyde tank pump 7 through a mixed butyraldehyde tank discharge pipeline 5, and the outlet of the mixed butyraldehyde tank pump 7 is simultaneously connected to a mixed butyraldehyde tank reflux pipeline 6 and a mixed butyraldehyde pump outlet pipeline 8, and the other end of the mixed butyraldehyde tank reflux pipeline 6 is connected to the mixed butyraldehyde tank 1, and the other end of the mixed butyraldehyde pump outlet pipeline 8 is connected to the feed port of the isobutyraldehyde refining tower 9. The isobutyraldehyde refining tower 9 is a floating valve tower, which is provided with 40 layers of tower plates, and the top pressure is controlled at 70-105 kpa. The temperature at the 25th tower plate in the middle and upper part is the sensitive plate temperature, which is controlled at 75-95 ° C. The top of the isobutyraldehyde refining tower 9 is connected with an isobutyraldehyde refining tower gas phase pipeline 10, and the other end of the isobutyraldehyde refining tower gas phase pipeline 10 is connected to the pipe side inlet of the cooler 14, and the pipe side outlet of the cooler 14 and the top of the reflux tank 16 are connected by the cooler lower liquid pipeline 15. The reflux tank 16 is connected to the inlet of the reflux pump 21 by a reflux tank discharge pipeline 20, and the outlet of the reflux pump 21 is simultaneously connected to the isobutyraldehyde refining tower top reflux pipeline 11, the reflux tank reflux pipeline 17 and the reflux pump discharge pipeline 22, the other end of the isobutyraldehyde refining tower top reflux pipeline 11 is connected to the upper side line of the isobutyraldehyde refining tower 9, the other end of the reflux tank reflux pipeline 17 is connected to the top of the reflux tank 16, and the other end of the reflux pump discharge pipeline 22 goes to the isobutyraldehyde qualified product tank. The bottom of the isobutyraldehyde refining tower 9 is connected to the inlet of the bottom pump 23 by the isobutyraldehyde refining tower bottom discharge pipeline 13, and the outlet of the bottom pump 23 is simultaneously connected to the isobutyraldehyde refining tower bottom reflux pipeline 12 and the bottom pump discharge pipeline 24, the other end of the bottom pump discharge pipeline 24 leads to the feed pipeline of the normal isobutyraldehyde separation tower, and the other end of the isobutyraldehyde refining tower bottom reflux pipeline 12 is connected to the lower side line of the isobutyraldehyde refining tower 9.

[0006] Furthermore, it also includes the circulating water supply pipeline 30 and the circulating water return pipeline 31. The circulating water supply pipeline 30 is connected to the lower shell side of the cooler 14, and the circulating water return pipeline 31 is connected to the upper shell side of the cooler 14.

[0007] Furthermore, it also includes a reflux tank venting pipeline 18 and a nitrogen supply pipeline 19. The reflux tank venting pipeline 18 and the nitrogen supply pipeline 19 are respectively connected to the venting and nitrogen supply corresponding pipelines of the normal-isobutyraldehyde separation tower.

[0008] Furthermore, a venting pipeline 3 of the mixed butyraldehyde tank and a nitrogen replenishing pipeline 4 of the mixed butyraldehyde tank are also provided.

[0009] Furthermore, a reboiler 25 is included, and the reboiler 25 is connected with a reboiler tube feed pipeline 26, a reboiler discharge pipeline 27, a reboiler steam inlet pipeline 28, and a reboiler condensate outlet pipeline 29. The other end of the reboiler tube feed pipeline 26 is connected to the kettle of the isobutyraldehyde refining tower 9, the other end of the reboiler tube discharge pipeline 27 is connected to the lower part of the isobutyraldehyde refining tower 9, the reboiler steam inlet pipeline 28 is connected between the steam outlet of the steam system and the shell side of the reboiler 25, and the other end of the reboiler condensate outlet pipeline 29 goes to the condensate system.

[0010] The beneficial effect of adopting the above technical solution is: a system for purifying isobutyraldehyde can effectively solve the problem of separation difficulty in the isobutyraldehyde separation tower and solve the bottleneck of system dosage through the technical solution.

[0011] In traditional technology, a distillation tower is used to separate butyraldehyde. The tower is very tall, has a large diameter and many plates. The tower height and diameter have high requirements on the local geographical conditions and the foundation of the distillation tower, and the investment cost is also relatively high. The large number of plates adds a lot of difficulties to the system shutdown and maintenance. The high tower height, large tower diameter and large number of plates of the distillation tower also increase the daily operating costs. This utility model patent uses a storage tank and a small distillation tower to effectively solve the bottleneck of the original system addition, and also saves investment costs.

[0012] The technical solution can effectively separate isobutyraldehyde from the isobutyraldehyde mixture, effectively solving problem 1): the problem of incomplete separation in the isobutyraldehyde separation tower; solving problem 2): for some isobutyraldehyde-using enterprises, the purchase or storage of isobutyraldehyde is contaminated and cannot meet the quality required for production, and further separation is required; solving problem 3): for isobutyraldehyde production enterprises, in order to meet customers with different quality requirements and produce isobutyraldehyde products of different concentrations, only a single small tower can be adjusted within a certain range to solve the problem BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall connection structure of the utility model.

[0014] In the figure, 1-mixed butyraldehyde tank, 2-mixed butyraldehyde tank feed pipeline, 3-mixed butyraldehyde tank vent pipeline, 4-mixed butyraldehyde tank nitrogen supplement pipeline, 5-mixed butyraldehyde tank discharge pipeline, 6-mixed butyraldehyde tank reflux pipeline, 7-mixed butyraldehyde tank pump, 8-mixed butyraldehyde pump outlet pipeline, 9-isobutyraldehyde refining tower, 10-isobutyraldehyde refining tower gas phase pipeline, 11-isobutyraldehyde refining tower top reflux pipeline, 12-isobutyraldehyde refining tower kettle reflux pipeline, 13-isobutyraldehyde refining tower kettle discharge pipeline, 14-cooler, 15-cooler Cooler lower liquid pipeline, 16-reflux tank, 17-reflux tank reflux pipeline, 18-reflux tank vent pipeline, 19-nitrogen supplement pipeline, 20-reflux tank discharge pipeline, 21-reflux pump, 22-reflux pump discharge pipeline, 23-tower bottom pump, 24-tower bottom pump discharge pipeline, 25-reboiler, 26-reboiler tube feed pipeline, 27-reboiler discharge pipeline, 28-reboiler steam inlet pipeline, 29-reboiler condensate outlet pipeline, 30-cooler circulating water supply pipeline, 31-cooler circulating water return pipeline. DETAILED DESCRIPTION

[0015] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0016] like Figure 1 As shown, the utility model relates to an isobutyraldehyde separation and purification system, which is arranged downstream of an existing normal isobutyraldehyde separation tower. The normal isobutyraldehyde separation tower extracts mixed butyraldehyde from the side line, wherein the isobutyraldehyde content is substantially around 80%. An isobutyraldehyde separation and purification system described in this embodiment includes a mixed butyraldehyde tank 1, a mixed butyraldehyde tank pump 7, an isobutyraldehyde refining tower 9, a cooler 14, a reflux tank 16, a reflux pump 21, and a tower bottom pump 23. The upper side line extraction pipeline of the positive isobutyraldehyde separation tower is connected to the mixed butyraldehyde tank 1 through a mixed butyraldehyde tank feed pipeline 2. The working pressure of the mixed butyraldehyde tank 1 is 0-20KPa. The mixed butyraldehyde tank 1 is connected to the inlet of the mixed butyraldehyde tank pump 7 through a mixed butyraldehyde tank discharge pipeline 5. The outlet of the mixed butyraldehyde tank pump 7 is simultaneously connected to a mixed butyraldehyde tank reflux pipeline 6 and a mixed butyraldehyde pump outlet pipeline 8. The other end of the mixed butyraldehyde tank reflux pipeline 6 is connected to the mixed butyraldehyde tank 1, and the other end of the mixed butyraldehyde pump outlet pipeline 8 is connected to the feed port of the isobutyraldehyde refining tower 9.

[0017] The isobutyraldehyde refining tower 9 is a floating valve tower, which is provided with 40 layers of tower plates, and the top pressure is controlled at 70-105 kpa. The temperature at the 25th tower plate in the middle and upper part is the sensitive plate temperature, which is controlled at 75-95 ° C. The top of the isobutyraldehyde refining tower 9 is connected with an isobutyraldehyde refining tower gas phase pipeline 10, and the other end of the isobutyraldehyde refining tower gas phase pipeline 10 is connected to the pipe side inlet of the cooler 14, and the pipe side outlet of the cooler 14 and the top of the reflux tank 16 are connected by the cooler lower liquid pipeline 15. The reflux tank 16 is connected to the inlet of the reflux pump 21 by a reflux tank discharge pipeline 20, and the outlet of the reflux pump 21 is simultaneously connected to the isobutyraldehyde refining tower top reflux pipeline 11, the reflux tank reflux pipeline 17 and the reflux pump discharge pipeline 22, the other end of the isobutyraldehyde refining tower top reflux pipeline 11 is connected to the upper side line of the isobutyraldehyde refining tower 9, the other end of the reflux tank reflux pipeline 17 is connected to the top of the reflux tank 16, and the other end of the reflux pump discharge pipeline 22 goes to the isobutyraldehyde qualified product tank. The bottom of the isobutyraldehyde refining tower 9 is connected to the inlet of the bottom pump 23 by the isobutyraldehyde refining tower bottom discharge pipeline 13, and the outlet of the bottom pump 23 is simultaneously connected to the isobutyraldehyde refining tower bottom reflux pipeline 12 and the bottom pump discharge pipeline 24, the other end of the bottom pump discharge pipeline 24 leads to the feed pipeline of the normal isobutyraldehyde separation tower, and the other end of the isobutyraldehyde refining tower bottom reflux pipeline 12 is connected to the lower side line of the isobutyraldehyde refining tower 9.

[0018] As a further embodiment, the circulating water supply pipeline 30 is connected to the lower shell side of the cooler 14 , and the circulating water return pipeline 31 is connected to the upper shell side of the cooler 14 .

[0019] As a further embodiment, the isobutyraldehyde separation and purification system also includes a reflux tank venting pipeline 18 and a nitrogen supply pipeline 19. The reflux tank venting pipeline 18 and the nitrogen supply pipeline 19 are respectively connected to the venting and nitrogen supply corresponding pipelines of the isobutyraldehyde separation tower.

[0020] As a further embodiment, the isobutyraldehyde separation and purification system further includes a mixed butyraldehyde tank venting pipeline 3 and a mixed butyraldehyde tank nitrogen replenishing pipeline 4.

[0021] As a further embodiment, the isobutyraldehyde separation and purification system further comprises a reboiler 25, to which a reboiler tube feed line 26, a reboiler discharge line 27, a reboiler steam inlet line 28, and a reboiler condensate outlet line 29 are connected. The other end of the reboiler tube feed line 26 is connected to the kettle of the isobutyraldehyde refining tower 9, the other end of the reboiler tube discharge line 27 is connected to the lower part of the isobutyraldehyde refining tower 9, the reboiler steam inlet line 28 is connected between the steam outlet of the steam system and the shell side of the reboiler 25, and the other end of the reboiler condensate outlet line 29 goes to the condensate system.

[0022] When the utility model is working, the normal isobutyraldehyde separation tower controls appropriate indicators, the tower bottom produces qualified normal butyraldehyde, and the mixed butyraldehyde (isobutyraldehyde content is basically about 80%) produced by the side line of the normal isobutyraldehyde separation tower is sent to the mixed butyraldehyde tank 1 by using the potential difference. The pressure of the mixed butyraldehyde tank 1 is controlled at 0-20kpa, and the top pressure of the mixed butyraldehyde tank 1 is controlled by the venting pipeline 3 and the nitrogen supplement pipeline 4. The material in the mixed butyraldehyde tank 1 is sent to the isobutyraldehyde refining tower 9 through the mixed butyraldehyde tank pump outlet pipeline 8 by the mixed butyraldehyde tank pump 7. The isobutyraldehyde refining tower 9 is a floating valve tower with a total of 40 tower plates, and the top pressure is controlled at about 70-105kpa. The 25th tower plate in the upper middle of the tower plate is a sensitive plate, and the temperature of the sensitive plate is controlled to be 75-95℃. When the gas phase on the top of the isobutyraldehyde refining tower 9 is condensed to 30-50°C by the cooler 14, the liquid phase goes to the reflux tank 16, and the material in the reflux tank 16 (isobutyraldehyde content is more than 99.7%) is sent to the isobutyraldehyde qualified product tank of the device through the reflux pump 21 and the reflux pump outlet pipeline 22. The mixed butyraldehyde (normal butyraldehyde content is about 70-90%) in the bottom of the isobutyraldehyde refining tower 9 is sent to the normal isobutyraldehyde tower for re-separation. This utility model patent uses a storage tank and a small distillation tower to effectively solve the bottleneck of the original system addition, and after the small distillation tower is added, the mixed aldehyde containing about 80% isobutyraldehyde extracted from the original tower top is separated into a high-quality isobutyraldehyde product containing 99.7%, saving investment costs.

[0023] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. The protection scope of the present invention shall be subject to the contents of the claims.

Claims

1. An isobutyraldehyde separation and purification system, comprising a normal isobutyraldehyde separation tower and an isobutyraldehyde qualified product tank, characterized in that: The invention also comprises a mixed butyraldehyde tank (1), a mixed butyraldehyde tank pump (7), an isobutyraldehyde refining tower (9), a cooler (14), a reflux tank (16), a reflux pump (21), and a tower bottom pump (23). The upper side line extraction pipeline of the normal isobutyraldehyde separation tower is connected to the mixed butyraldehyde tank (1) through a mixed butyraldehyde tank feed pipeline (2). The mixed butyraldehyde tank (1) is connected to the inlet of the mixed butyraldehyde tank pump (7) through a mixed butyraldehyde tank discharge pipeline (5). The outlet of the mixed butyraldehyde tank pump (7) is simultaneously connected to the mixed butyraldehyde tank reflux pipeline (6) and the mixed butyraldehyde tank pump (7). The butyraldehyde pump outlet pipeline (8) is connected to the mixed butyraldehyde tank reflux pipeline (6) at the other end thereof and connected to the mixed butyraldehyde tank (1). The mixed butyraldehyde pump outlet pipeline (8) is connected to the feed port of the isobutyraldehyde refining tower (9) at the other end thereof. The top of the isobutyraldehyde refining tower (9) is connected to the isobutyraldehyde refining tower gas phase pipeline (10). The other end of the isobutyraldehyde refining tower gas phase pipeline (10) is connected to the tube side inlet of the cooler (14). The tube side outlet of the cooler (14) and the top of the reflux tank (16) are connected via a cooler lower liquid pipeline (15). The reflux tank (16) and the inlet of the reflux pump (21) are connected via a reflux tank discharge pipeline (20), and the outlet of the reflux pump (21) is simultaneously connected to the isobutylaldehyde refining tower top reflux pipeline (11), the reflux tank reflux pipeline (17) and the reflux pump discharge pipeline (22), the other end of the isobutylaldehyde refining tower top reflux pipeline (11) is connected to the upper side line of the isobutylaldehyde refining tower (9), the other end of the reflux tank reflux pipeline (17) is connected to the top of the reflux tank (16), and the reflux pump discharge pipeline (22) is connected to the outlet of the reflux pump (21). 2) the other end leads to the isobutyraldehyde qualified product tank; the bottom of the isobutyraldehyde refining tower (9) is connected to the inlet of the bottom pump (23) via the isobutyraldehyde refining tower bottom discharge pipeline (13), the outlet of the bottom pump (23) is simultaneously connected to the isobutyraldehyde refining tower bottom reflux pipeline (12) and the bottom pump discharge pipeline (24), the other end of the bottom pump discharge pipeline (24) leads to the feed pipeline of the normal isobutyraldehyde separation tower, and the other end of the isobutyraldehyde refining tower bottom reflux pipeline (12) is connected to the lower side line of the isobutyraldehyde refining tower (9).

2. A system for separating and purifying isobutyraldehyde according to claim 1, characterized in that: It also includes a circulating water supply pipeline (30) and a circulating water return pipeline (31), wherein the circulating water supply pipeline (30) is connected to the lower shell side of the cooler (14), and the circulating water return pipeline (31) is connected to the upper shell side of the cooler (14).

3. A system for separating and purifying isobutyraldehyde according to claim 1, characterized in that: The invention also comprises a reflux tank venting pipeline (18) and a nitrogen supply pipeline (19), wherein the reflux tank venting pipeline (18) and the nitrogen supply pipeline (19) are respectively connected to the venting and nitrogen supply pipelines of the normal-isobutyraldehyde separation tower.

4. A system for separating and purifying isobutyraldehyde according to claim 1, characterized in that: It also includes a mixed butyraldehyde tank venting pipeline (3) and a mixed butyraldehyde tank nitrogen replenishing pipeline (4).

5. The isobutyraldehyde separation and purification system according to claim 1, characterized in that: The invention also comprises a reboiler (25), to which a reboiler tube-side feed pipeline (26), a reboiler discharge pipeline (27), a reboiler steam inlet pipeline (28), and a reboiler condensate outlet pipeline (29) are connected; the other end of the reboiler tube-side feed pipeline (26) is connected to the kettle of the isobutyraldehyde refining tower (9), the other end of the reboiler tube-side discharge pipeline (27) is connected to the lower part of the isobutyraldehyde refining tower (9), the reboiler steam inlet pipeline (28) is connected between the steam outlet of the steam system and the shell side of the reboiler (25), and the other end of the reboiler condensate outlet pipeline (29) leads to the condensate system.

6. The isobutyraldehyde separation and purification system according to claim 1, characterized in that: The isobutyraldehyde refining tower (9) is a floating valve tower, and 40 layers of tower trays are arranged in the tower, and a sensitive plate is arranged at the 25th layer of the tower tray in the middle and upper part.

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