System for separating n-butyl alcohol from water by using rectification-membrane separation integrated process

Abstract

The utility model discloses a system for separating n-butyl alcohol from water by using a rectification-membrane separation integrated process. The system comprises an azeotropic rectification tower, a reboiler, a NaA molecular sieve pervaporation membrane device, a reflux pump and an n-butyl alcohol extraction pump, a feeding pipeline is arranged in the middle of the azeotropic rectifying tower, a gas phase outlet pipe is arranged at the top of the azeotropic rectifying tower, and a discharging pipe is arranged at the bottom of the azeotropic rectifying tower; the NaA molecular sieve pervaporation membrane device is arranged at the tower top, azeotrope of n-butanol and water can be effectively separated, a traditional azeotropic distillation process and a novel molecular sieve membrane dehydration separation technology are combined, azeotropic limitation of the n-butanol-water mixture is effectively broken through, efficient recovery of the two substances is achieved, and the production cost is reduced. The system is energy-saving, environment-friendly, high in recovery rate, low in investment and suitable for industrial application and popularization.

Description

Technical Field

[0001] This utility model relates to the technical field of n-butanol-water separation, specifically to a n-butanol-water separation system using an integrated distillation-membrane separation process. Background Technology

[0002] Common methods for treating azeotropic systems include: extractive distillation, azeotropic distillation, pressure swing distillation, membrane separation, adsorption, dual-tower ordinary distillation, and pervaporation.

[0003] For a partially miscible system of n-butanol and water, the conventional process is as follows: two azeotropic distillation columns are set up, and a separator is installed at the top of the columns to separate the phases. The azeotrope condensed from the vapor phase at the top of the two azeotropic distillation columns enters the separator for settling and separation. The oil phase is returned to the top of the first azeotropic distillation column, and the water phase enters the top of the second distillation column. After distillation, n-butanol is collected from the bottom of the first distillation column, and water is collected from the bottom of the second distillation column.

[0004] CN117839247A proposes a system for continuous separation of n-butanol and water azeotropic system using distillation-membrane separation. This system uses liquid phase membrane separation to replace the separator, and other equipment and process flow are the same as conventional processes. However, it suffers from the drawbacks of large investment and high energy consumption. To address these issues, we propose an integrated distillation-membrane separation process for separating n-butanol and water. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a system for separating n-butanol and water using an integrated distillation-membrane separation process.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] This utility model discloses a system for separating n-butanol and water using an integrated distillation-membrane separation process, comprising an azeotropic distillation column, a reboiler, a NaA molecular sieve pervaporation membrane device, a reflux pump, and a n-butanol collection pump; the azeotropic distillation column is provided with a feed pipeline in the middle, a gas phase outlet pipe at the top, and a discharge pipe at the bottom;

[0008] The inlet of the NaA molecular sieve pervaporation membrane device is connected to the gas phase outlet pipe, and the butanol phase outlet of the NaA molecular sieve pervaporation membrane device is connected to the inlet of the reflux pump through a pipe. The inlet of the reflux pump is connected to the upper inlet of the azeotropic distillation column, and the outlet pipe is connected to the inlet of the n-butanol collection pump through a pipe. The inlet of the reboiler is connected to the bottom of the azeotropic distillation column through the first pipe, and the inlet of the reboiler is connected to the upper side of the bottom of the azeotropic distillation column.

[0009] As a preferred embodiment of this utility model, the NaA molecular sieve pervaporation membrane device is provided in two parallel configurations. The butanol phase outlet of each NaA molecular sieve pervaporation membrane device is connected to the inlet of a reflux pump via a pipeline. Each NaA molecular sieve pervaporation membrane device is equipped with a solenoid valve at its inlet. Furthermore, a butanol sensor for detecting butanol is provided on the aqueous phase of each NaA molecular sieve pervaporation membrane device.

[0010] As a preferred technical solution of this utility model, the top of the inner cavity of the azeotropic distillation column is provided with a first annular tube, and the first annular tube is provided with a first spray hole, and the first annular tube is connected to the outlet of the reflux pump.

[0011] As a preferred embodiment of the present invention, the inner cavity of the azeotropic distillation column is provided with a second annular tube, and the second annular tube is provided with a second spray hole, and the second annular tube is connected to the feed inlet of the reboiler.

[0012] As a preferred embodiment of this utility model, the NaA molecular sieve pervaporation membrane device includes a cylindrical body, a downwardly recessed water storage chamber at the bottom of the cylindrical body, a funnel-shaped NaA molecular sieve with a narrow head facing the inner cavity of the cylindrical body installed on one side of the cylindrical body, a flow guide plate on the outside of the NaA molecular sieve, a liquid level sensor for detecting the liquid level in the water storage chamber inside the cylindrical body, and a controller. The liquid level sensor and the reflux pump are both connected to the controller, and the controller controls the operation of the reflux pump according to the liquid level detected by the liquid level sensor.

[0013] The beneficial effects of this utility model are:

[0014] 1. This integrated distillation-membrane separation process for separating n-butanol-water system, with a NaA molecular sieve pervaporation membrane device installed at the top of the column, can effectively separate the azeotropic mixture of n-butanol and water. By combining the traditional azeotropic distillation process with the novel molecular sieve membrane dehydration separation technology, it effectively breaks through the azeotropic limitation of the n-butanol-water mixture and achieves efficient recovery of both substances. This system is energy-saving, environmentally friendly, has a high recovery rate, and requires less investment, making it suitable for industrial application and promotion.

[0015] 2. This integrated distillation-membrane separation process for separating n-butanol-water systems has two NaA molecular sieve pervaporation membrane devices connected in parallel, which provides a high separation efficiency. The two NaA molecular sieve pervaporation membrane devices can be controlled independently, and if one of them is damaged, it can be shut down without affecting normal operation.

[0016] 3. In this integrated distillation-membrane separation process for separating n-butanol-water, a funnel-shaped NaA molecular sieve is used, which has a large permeation area and thus good permeation efficiency. A liquid level sensor is installed inside the cylinder to detect the liquid level in the water storage chamber, which facilitates automatic extraction of the water storage chamber. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0018] Figure 1 This is a schematic diagram of the structure of a n-butanol-water separation system using an integrated distillation-membrane separation process according to this utility model;

[0019] Figure 2 This is a schematic diagram of the structure of a NaA molecular sieve pervaporation membrane device for separating n-butanol-water system using an integrated distillation-membrane separation process according to this utility model.

[0020] Figure 3 This is a schematic diagram of a liquid level sensor assembly for a n-butanol-water separation system using an integrated distillation-membrane separation process according to this utility model.

[0021] In the diagram: 1. Azeotropic distillation column; 2. Reboiler; 3. NaA molecular sieve pervaporation membrane device; 301. Shell; 302. Water storage chamber; 303. NaA molecular sieve; 304. Drain plate; 305. Liquid level sensor; 306. Controller; 4. Reflux pump; 5. n-Butanol collection pump; 6. Feed line; 8. Discharge pipe; 9. Solenoid valve; 10. Butanol sensor; 11. First annular pipe; 12. First nozzle; 13. Second annular pipe; 14. Second nozzle. Detailed Implementation

[0022] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0023] Example: Figure 1 , Figure 2 , Figure 3As shown, this utility model discloses a system for separating n-butanol and water using an integrated distillation-membrane separation process. The system includes an azeotropic distillation column 1, a reboiler 2, a NaA molecular sieve pervaporation membrane device 3, a reflux pump 4, and a n-butanol collection pump 5. The azeotropic distillation column 1 has a feed line 6 in the middle, a vapor outlet pipe 7 at the top, and a discharge pipe 8 at the bottom. The NaA molecular sieve pervaporation membrane device at the top of the column effectively separates the azeotrope of n-butanol and water. By combining traditional azeotropic distillation with a novel molecular sieve membrane dehydration separation technology, this system effectively overcomes the azeotropic limitation of the n-butanol-water mixture, achieving efficient recovery of both substances. This system is energy-saving, environmentally friendly, has a high recovery rate, requires low investment, and is suitable for industrial application and promotion.

[0024] The inlet of the NaA molecular sieve pervaporation membrane device 3 is connected to the gas phase outlet pipe 7, and the butanol phase outlet of the NaA molecular sieve pervaporation membrane device 3 is connected to the inlet of the reflux pump 4 through a pipe. The inlet of the reflux pump 4 is connected to the upper inlet of the azeotropic distillation column 1. The outlet pipe 8 is connected to the inlet of the n-butanol collection pump 5 through a pipe. The inlet of the reboiler 2 is connected to the bottom of the azeotropic distillation column 1 through the first pipe, and the inlet of the reboiler 2 is connected to the upper side of the bottom of the azeotropic distillation column 1.

[0025] The NaA molecular sieve pervaporation membrane device 3 is provided in two parallel configurations. The butanol phase outlet of each NaA molecular sieve pervaporation membrane device 3 is connected to the inlet of the reflux pump 4 via a pipe. Each inlet of the NaA molecular sieve pervaporation membrane device 3 is equipped with a solenoid valve 9, and a butanol sensor 10 for butanol detection is installed on the aqueous phase of each NaA molecular sieve pervaporation membrane device 3. The parallel configuration of the two NaA molecular sieve pervaporation membrane devices 3 provides a high separation efficiency. Furthermore, the two NaA molecular sieve pervaporation membrane devices 3 can be controlled independently; if one is damaged, it can be shut down without affecting normal operation.

[0026] The azeotropic distillation column 1 has a first annular pipe 11 at the top of its inner cavity, and a first spray hole 12 on the first annular pipe 11. The first annular pipe 11 is connected to the outlet of the reflux pump 4, so that the n-butanol-water mixture refluxed into the azeotropic distillation column 1 is sprayed out, which is convenient for heating and thus has a better vaporization effect on the water.

[0027] The azeotropic distillation column 1 is provided with a second annular tube 13 in its inner cavity, and the second annular tube 13 is provided with a second spray hole 14. The second annular tube is connected to the feed inlet of the reboiler 2. In this way, the n-butanol-water mixture that flows back into the azeotropic distillation column 1 is sprayed out, which is convenient for heating and thus has a better vaporization effect on the water, which facilitates the purification of n-butanol.

[0028] The NaA molecular sieve pervaporation membrane device 3 includes a cylindrical body 301 with a recessed water storage chamber 302 at the bottom. A funnel-shaped NaA molecular sieve 303 with its narrow head facing the inner cavity is mounted on one side of the cylindrical body 301. A flow guide plate 304 is provided outside the NaA molecular sieve 303. A level sensor 305 for detecting the liquid level in the water storage chamber 302 is located inside the cylindrical body 301. The device also includes a controller 306, which connects both the level sensor 305 and a reflux pump 4. The controller 306 controls the reflux pump 4 based on the liquid level detected by the level sensor 305. The funnel-shaped NaA molecular sieve 303 provides a larger permeation area, resulting in better permeation efficiency. The level sensor 305 inside the cylindrical body 301 facilitates automatic extraction of the water storage chamber 302.

[0029] During operation, this integrated distillation-membrane separation process separates n-butanol-water systems. A NaA molecular sieve pervaporation membrane device is installed at the top of the column, effectively separating the azeotropic mixture of n-butanol and water. This combines traditional azeotropic distillation with novel molecular sieve membrane dehydration technology, effectively overcoming the azeotropic limitations of the n-butanol-water mixture and achieving efficient recovery of both substances. This system is energy-saving, environmentally friendly, has a high recovery rate, and requires low investment, making it suitable for industrial application and promotion. Two NaA molecular sieve 303 pervaporation membrane devices 3 are installed in parallel, resulting in a high separation efficiency. Each device can be controlled independently; if one breaks, it can be shut down without affecting normal operation. The funnel-shaped NaA molecular sieve 303 provides a large permeation area, resulting in good permeation efficiency. A level sensor 305 is installed inside the cylinder 301 to detect the liquid level in the water storage chamber 302, facilitating automatic extraction of the water storage chamber 302.

[0030] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A process for separating a n-butanol-water system by distillation-membrane separation integration, characterized in that: The device comprises azeotropic distillation column (1), reboiler (2), NaA molecular sieve pervaporation membrane device (3), reflux pump (4) and n-butanol extraction pump (5); the middle part of the azeotropic distillation column (1) is provided with a feed pipeline (6), and the top of the azeotropic distillation column (1) is provided with a gas phase outlet pipe (7), and the bottom of the azeotropic distillation column (1) is provided with a discharge pipe (8); The feed inlet of the NaA molecular sieve pervaporation membrane device (3) is connected with the gas phase outlet pipe (7), and the butanol phase discharge outlet of the NaA molecular sieve pervaporation membrane device (3) is connected with the feed inlet of the reflux pump (4) through a pipeline, the feed inlet of the reflux pump (4) is connected with the upper inlet of the azeotropic distillation column (1), and the discharge pipe (8) is connected with the feed inlet of the n-butanol extraction pump (5) through a pipeline; the feed inlet of the reboiler (2) is communicated with the bottom of the azeotropic distillation column (1) through a first pipeline, and the feed inlet of the reboiler (2) is communicated with the upper side of the bottom of the azeotropic distillation column (1).

2. The process according to claim 1 for separating n-butanol-water system by integrated rectification-membrane separation process, characterized in that, The NaA molecular sieve pervaporation membrane device (3) is provided with two and is arranged in parallel, the butanol phase discharge outlet of each NaA molecular sieve pervaporation membrane device (3) is connected with the feed inlet of the reflux pump (4) through a pipeline, and the feed inlet of each NaA molecular sieve pervaporation membrane device (3) is provided with a solenoid valve (9), and the water phase of the NaA molecular sieve pervaporation membrane device (3) is provided with a butanol sensor (10) for detecting butanol.

3. The process of claim 1, wherein the process is used for separating n-butanol-water system by integrated distillation-membrane separation process, characterized in that, The top of the inner cavity of the azeotropic distillation column (1) is provided with a first annular pipe (11), and the first annular pipe (11) is provided with a first spray hole (12), and the first annular pipe (11) is connected with the discharge outlet of the reflux pump (4).

4. The process of claim 2, wherein the process is used for separating n-butanol-water system by integrated distillation-membrane separation process, characterized in that, The inner cavity of the azeotropic distillation column (1) is provided with a second annular pipe (13), and the second annular pipe (13) is provided with a second spray hole (14), and the second annular pipe is connected with the feed inlet of the reboiler (2).

5. The process as claimed in claim 1, wherein the process for separating n-butanol-water system by integrated process of rectification-membrane separation is characterized by, The NaA molecular sieve pervaporation membrane device (3) comprises a cylinder body (301), the bottom of the cylinder body (301) is provided with a downward recessed water storage cavity (302), one side of the cylinder body (301) is provided with a funnel-shaped NaA molecular sieve (303) with a narrow head facing the inner cavity of the cylinder body, the outside of the NaA molecular sieve (303) is provided with a drainage plate (304), the cylinder body (301) is provided with a liquid level sensor (305) for detecting the liquid level in the water storage cavity (302), and a controller (306) is further included, the liquid level sensor (305) and the reflux pump (4) are connected with the controller (306), and the controller (306) controls the working of the reflux pump (4) according to the liquid level detected by the liquid level sensor (305).

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