Acrylic acid production and purification device

Abstract

The utility model provides an acrylic acid production and purification device, and relates to the technical field of chemical raw material production, the acrylic acid production and purification device comprises a preliminary distillation tower, forced circulation evaporation is performed through the preliminary distillation tower, during circulation evaporation, a polymerization inhibitor is continuously added, acrylic acid polymerization is prevented, crude acrylic acid is obtained after circulation evaporation, and then the crude acrylic acid is transferred to a polymerization inhibition section for purification of acrylic acid. The method comprises the following steps: conveying crude acrylic acid to a stirrer for stirring until the viscosity is proper, then conveying the crude acrylic acid to an extraction tower, and meanwhile, adding an extraction agent into the extraction tower for extraction, so that an acrylic acid mixed solution is extracted into an organic phase, and the crude acrylic acid is primarily purified; the extraction agent in the organic phase of the acrylic acid is separated from a mixed solution of acetic acid, acrylic acid and the like, the mixed solution enters an acetic acid recovery tower to recover acetic acid, the remaining materials continue to enter a heavy component removal tower to remove heavy components, and high-concentration acrylic acid light components are rectified again through a rectifying tower to remove impurities.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of chemical raw material production, in particular to a propenoic acid production and purification device. BACKGROUND

[0002] In the industrial production of propenal, a by-product propenoic acid is easily obtained, and the propenoic acid is an important organic synthesis raw material and a synthetic resin monomer, and is mainly used for preparing propenoic acid resin, propenoic acid esters (such as methyl ester, ethyl ester, butyl ester, hydroxyethyl ester and the like) and other compounds, so that the purification of the propenoic acid has high economic value.

[0003] However, in the prior art, the separation of the propenoic acid solution mainly adopts extraction, azeotropy, crystallization and the like, and the purification system is generally complex, and substances such as inhibitors and acetic acid are easily left, so that the purity of the final product is low, the work efficiency is low, the needs of industrial production cannot be met, and the industrial production cost is high, so that the application has defects. CONTENT OF THE INVENTION

[0004] In order to make up for the above defects, the application provides a propenoic acid production and purification device, which can improve the purity of the propenoic acid solution, is not easy to leave other substances, and has high production work efficiency.

[0005] The application is implemented in the following manner:

[0006] The preliminary distillation tower is fixedly connected with a stirrer, the stirrer is connected with an extraction tower, the top of the extraction tower is fixedly connected with a solvent separation tower, the bottom of the extraction tower is fixedly connected with an extraction recovery mechanism, the bottom of the solvent separation tower is fixedly connected with an acetic acid recovery tower, the bottom of the acetic acid recovery tower is fixedly connected with a heavy component removal tower, and the top of the heavy component removal tower is fixedly connected with a rectification tower.

[0007] In an embodiment of the application, the preliminary distillation tower is a circulating distillation tower, and the bottom liquid outlet of the preliminary distillation tower is fixedly connected with the liquid inlet of the stirrer.

[0008] In an embodiment of the application, the liquid inlet of the extraction tower is connected with the bottom liquid outlet of the stirrer, the top of the extraction tower is provided with an organic phase outlet connected with the top of the solvent separation tower, and the bottom of the extraction tower is provided with a residual phase outlet connected with the extraction recovery mechanism.

[0009] In an embodiment of the application, a fractional distillation is arranged in the extraction recovery mechanism, the extraction recovery mechanism is respectively provided with an extractant outlet and a wastewater outlet, and the extractant outlet is fixedly connected with the extraction tower.

[0010] In an embodiment of the present application, the solvent separation tower is communicated at the top with the extractant outlet of the extraction recovery mechanism, and the bottom of the solvent separation tower is communicated with the inlet of the acetic acid recovery tower.

[0011] In an embodiment of the present application, the acetic acid recovery tower comprises a first recovery tower and a second recovery tower, the first recovery tower is communicated with the bottom of the solvent separation tower, the second recovery tower is fixedly communicated with the top of the first recovery tower, the second recovery tower is provided with an acetic acid recovery outlet, and the bottom of the first recovery tower is fixedly communicated with the heavy component removal tower.

[0012] In an embodiment of the present application, the top of the heavy component removal tower is fixedly communicated with the rectification tower, and the bottom of the heavy component removal tower is provided with a heavy component removal outlet.

[0013] In an embodiment of the present application, the rectification tower comprises a cooler and a rectification tower body, the cooler is fixedly communicated with the top of the heavy component removal tower, the rectification tower body is fixedly communicated with the cooler, and the top end of the rectification tower body is provided with a finished product outlet.

[0014] The beneficial effects of the present application are: through the forced circulation evaporation of the preliminary distillation tower, the polymerization of acrylic acid is prevented by continuously adding the polymerization inhibitor during the circulation evaporation, the crude acrylic acid is obtained after the circulation evaporation, and then the crude acrylic acid is transferred to the polymerization inhibitor section for purification, that is, the crude acrylic acid is transported to the stirrer for stirring, after the stirring reaches the appropriate viscosity, the crude acrylic acid is sent to the extraction tower, and an extractant is added in the extraction tower for extraction, so that the acrylic acid mixture is extracted into the organic phase, the crude acrylic acid is preliminarily purified, and the organic phase of the acrylic acid enters the solvent separation tower, the solvent separation tower is provided with a fractionation mechanism, so that the extractant in the organic phase of the acrylic acid is separated from the mixed solution of acetic acid, acrylic acid and the like, the separated extractant and the residual organic phase in the extraction tower are recycled in the extraction recovery mechanism, the recycled extractant is added to the extraction tower for repeated use, and the mixed solution of acetic acid, acrylic acid and the like is recycled in the acetic acid recovery tower, acetic acid is discharged through the acetic acid recovery tower, and subsequent acetic acid products can be obtained, and the remaining material continues to enter the heavy component removal tower for heavy component removal, so that the high-concentration acrylic acid light component passes through the top of the heavy component removal tower and reaches the rectifying tower, other heavy components such as dimers and polymerization inhibitors are discharged through the bottom of the heavy component removal tower, the high-concentration acrylic acid light component is subjected to rectification and impurity removal in the rectifying tower again to form acrylic acid with extremely high purity, and subsequent acrylic acid products with extremely high purity are obtained conveniently. Through the forced circulation evaporation, the polymerization inhibitor section and the rectification and impurity removal, the high-concentration solvent of the by-product acrylic acid is obtained in the industrial production of propylene aldehyde, the high-concentration solvent can be used for industrial production, the purification efficiency is high, the cost of industrial production is reduced, and thus the problems of the prior art, such as the complex purification system, the easy residual of the polymerization inhibitor, acetic acid and the like, the low purity of the final product, the low work efficiency and the high cost of industrial production, are solved. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0016] Figure 1 A structure diagram of an acrylic acid production and purification device is provided for the embodiments of the present application.

[0017] Figure 2 A working flowchart of an acrylic acid production and purification device is provided for the embodiments of the present application.

[0018] In the figure: 1 - preliminary distillation column; 2 - stirrer; 3 - extraction column; 4 - solvent separation column; 5 - extraction recovery mechanism; 6 - acetic acid recovery column; 61 - first recovery column; 62 - second recovery column; 7 - heavy-removal column; 8 - rectification column; 81 - cooler; 82 - rectification column body; DETAILED DESCRIPTION

[0019] Some embodiments of the present application will be described in detail with reference to the drawings. In the case of no conflict, the following examples and features in the examples can be combined with each other.

[0020] As Figures 1-2 shown, an acrylic acid production purification device according to an embodiment of the present application includes:

[0021] The preliminary distillation tower 1 is fixedly connected with the stirrer 2, the stirrer 2 is connected with the extraction tower 3, the top of the extraction tower 3 is fixedly connected with the solvent separation tower 4, the bottom of the extraction tower 3 is fixedly connected with the extraction recovery mechanism 5, the bottom of the solvent separation tower 4 is fixedly connected with the acetic acid recovery tower 6, the bottom of the acetic acid recovery tower 6 is fixedly connected with the heavy component removal tower 7, and the top of the heavy component removal tower 7 is fixedly connected with the rectification tower 8. The crude acrylic acid is obtained through forced circulation evaporation of the preliminary distillation tower 1, and the polymerization of acrylic acid is prevented by continuously adding a polymerization inhibitor during the circulation evaporation. After the circulation evaporation, the crude acrylic acid is purified by the polymerization inhibitor section, that is, the crude acrylic acid is sent to the stirrer 2 for stirring, and then is sent to the extraction tower 3 after being stirred to a suitable viscosity. At the same time, an extractant is added to the extraction tower 3 for extraction, so that the acrylic acid mixture is extracted into the organic phase, and the crude acrylic acid is preliminarily purified. The organic phase of the acrylic acid enters the solvent separation tower 4, and the solvent separation tower 4 is provided with a fractionation mechanism to separate the extractant in the organic phase of the acrylic acid from the mixed solution of acetic acid, acrylic acid and the like. The separated extractant and the residual organic phase in the extraction tower 3 are recovered in the extraction recovery mechanism 5. The recovered extractant is added to the extraction tower 3 for reuse, and the mixed solution of acetic acid, acrylic acid and the like enters the acetic acid recovery tower 6 for recovery of acetic acid. The acetic acid is discharged from the acetic acid recovery tower 6, and a finished product of acetic acid can be obtained subsequently. The remaining material continuously enters the heavy component removal tower 7 for heavy component removal, so that the high-concentration acrylic acid light component passes through the top of the heavy component removal tower 7 to the rectification tower 8, and other heavy component substances such as dimers and polymerization inhibitors are discharged from the bottom of the heavy component removal tower 7. The high-concentration acrylic acid light component is subjected to rectification and impurity removal in the rectification tower 8 again to form acrylic acid with extremely high purity, so that a finished product of acrylic acid with extremely high purity can be obtained subsequently. The device uses forced circulation evaporation, a polymerization inhibitor section and rectification and impurity removal to form a high-concentration solvent of by-product acrylic acid in the industrial production of propylene aldehyde. The high-concentration solvent can be used for industrial production, has high purification efficiency and reduces the cost of industrial production, thereby solving the problems of a complex purification system, easy residual polymerization inhibitor, acetic acid and other substances, low purity of the final product, low work efficiency and high industrial production cost in the prior art.

[0022] As Figure 1As shown, the primary distillation column 1 is a circulating distillation column, and the bottom outlet of the primary distillation column 1 is fixedly connected to the liquid inlet of the stirrer 2. The primary distillation column 1 is used for circulating evaporation, and when the solvent obtained in the industrial production of acrolein is a mixed solvent with many impurities, the circulating distillation can preliminarily remove the impurities, so that the mixed solvent forms a crude acrylate solvent. The liquid inlet of the extraction column 3 is connected to the bottom outlet of the stirrer 2, the top of the extraction column 3 is provided with an organic phase outlet connected to the top of the solvent separation column 4, and the bottom of the extraction column 3 is provided with a residual phase outlet connected to the extraction recovery mechanism 5. The extraction column 3 is used for water-soluble extraction of acrylate, and the solvent separation column 4 is used for separating the extractant in the acrylate solvent. After the crude acrylate solvent is stirred, it is easy to be water-soluble extracted, and after the crude acrylate solvent is mixed with the extractant, the pure acrylate and acetic acid in the crude acrylate solvent will move from the water phase to the organic phase, so that most of the impurities are separated, and a high-concentration acrylate mixed solvent is obtained. After the distillation of the solvent separation column 4, the extractant in the high-concentration acrylate mixed solvent is separated, so as to further increase the concentration of acrylate in the mixed solvent. The extraction recovery mechanism 5 is provided with a distillation, and the extraction recovery mechanism 5 is provided with an extractant outlet and a waste water outlet, respectively, and the extractant outlet is fixedly connected to the extraction column 3. The extraction recovery mechanism 5 is used for recycling the residual extraction residual phase in the extraction column 3 and the extractant separated after the solvent separation column 4. The top of the solvent separation column 4 is connected to the extractant outlet of the extraction recovery mechanism 5, and the bottom outlet of the solvent separation column 4 is connected to the inlet of the acetic acid recovery column 6. Through this setting, the separated extractant in the solvent separation column 4 can enter the extraction recovery mechanism 5, which is convenient for recycling, and the bottom outlet of the solvent separation column 4 is a high-concentration acrylate mixed solvent.

[0023] Further, the acetic acid recovery column 6 includes a first recovery column 61 and a second recovery column 62, the first recovery column 61 is connected to the bottom of the solvent separation column 4, the second recovery column 62 is fixedly connected to the top of the first recovery column 61, and the second recovery column 62 is provided with an acetic acid recovery outlet. The bottom of the first recovery column 61 is fixedly connected to the heavy component removal tower 7. The high-concentration acrylate mixed solvent separates acetic acid substances through the first recovery column 61, the acetic acid substances are further purified and impurities are removed through the second recovery column 62, which is convenient for subsequent processes to produce acetic acid raw materials that can be used in industry, and the remaining substances are transported to the heavy component removal tower 7 through the bottom of the first recovery column 61.

[0024] Further, the top of the heavy component removal tower 7 is fixedly connected to the rectification column 8, and the bottom of the heavy component removal tower 7 is provided with a heavy component outlet. The heavy component removal tower 7 is used for heavy component removal, so that the high-purity acrylate is further removed, the light components formed therein enter the rectification column 8 through the top of the heavy component removal tower 7 for further impurity removal, and the heavy components formed are discharged through the heavy component outlet, at this time, the acrylate content in the light components is extremely high.

[0025] Further, the rectification tower 8 includes a cooler 81 fixedly connected to the top of the heavy tower 7 and a rectification tower body 82 fixedly connected to the cooler 81, and the top end of the rectification tower body 82 is provided with a finished product discharge outlet. The light components form an aqueous solution after passing through the cooler 81, and are further rectified through the rectification tower body 82, so that the content of acrylic acid is further increased, thereby facilitating the formation of high-purity acrylic acid finished product in the subsequent process.

[0026] In summary, the working principle of the acrylic acid production and purification device in the embodiment of the present application is as follows: through the forced circulation evaporation of the preliminary distillation tower 1, the polymerization of acrylic acid is prevented by continuously adding a polymerization inhibitor during the circulation evaporation, and the crude acrylic acid is obtained after the circulation evaporation, and then the crude acrylic acid is transferred to the stirring device 2 for purification, that is, the crude acrylic acid is transported to the stirring device 2 for stirring, and after the stirring reaches a suitable viscosity, the crude acrylic acid is sent to the extraction tower 3, and an extracting agent is added to the extraction tower 3 at the same time for extraction, so that the acrylic acid mixture is extracted into the organic phase, and the crude acrylic acid is preliminarily purified, the organic phase of the acrylic acid enters the solvent separation tower 4, the solvent separation tower 4 is provided with a fractionation mechanism, so that the extracting agent in the organic phase of the acrylic acid is separated from the mixed solution of acetic acid, acrylic acid and the like, the separated extracting agent and the residual organic phase in the extraction tower 3 are sent to the extraction recovery mechanism 5 for recovery, the recovered extracting agent is added to the extraction tower 3 for reuse, and the mixed solution of acetic acid, acrylic acid and the like enters the first recovery tower 61 for separation of acetic acid substances, the acetic acid substances are further purified and impurities are removed through the second recovery tower 62, so that the acetic acid raw material for industrial use is conveniently prepared in the subsequent process, and the remaining substances are transported to the heavy-removing tower 7 through the bottom of the first recovery tower 61 for heavy-removing, so that the high-concentration acrylic acid light components pass through the top of the heavy-removing tower 7 to the rectification tower 8, and other heavy components such as dimers and polymerization inhibitors are discharged through the bottom of the heavy-removing tower 7, the high-concentration acrylic acid light components form an aqueous solution after passing through the cooler 81, and are further rectified through the rectification tower body 82, so that the content of acrylic acid is further increased, thereby facilitating the formation of high-purity acrylic acid finished product in the subsequent process, the device realizes forced circulation evaporation, polymerization inhibitor segmentation and rectification impurity removal, so that the by-product acrylic acid is formed into a high-concentration solvent in the industrial production of acrylic aldehyde, the high-concentration solvent can be used for industrial production, the purification efficiency is high, the cost of industrial production is reduced, and the problems of the prior art, such as complex purification system, easy residual polymerization inhibitor, acetic acid and other substances, low purity of the final product, low work efficiency and high industrial production cost, are solved.

[0027] The above merely provides examples of the present application, and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

Claims

1. An acrylic acid production and purification apparatus, characterized in that, include: A preliminary distillation column (1) is fixedly connected to a stirrer (2), the stirrer (2) is connected to an extraction column (3), the top of the extraction column (3) is fixedly connected to a solvent separation column (4), the bottom of the extraction column (3) is fixedly connected to an extraction recovery mechanism (5), the bottom of the solvent separation column (4) is fixedly connected to an acetic acid recovery column (6), the bottom of the acetic acid recovery column (6) is fixedly connected to a de-heavy column (7), and the top of the de-heavy column (7) is fixedly connected to a rectification column (8).

2. The acrylic acid production and purification apparatus according to claim 1, characterized in that, The preliminary distillation column (1) is a circulating distillation column, and the bottom outlet of the preliminary distillation column (1) is fixedly connected to the inlet of the stirrer (2).

3. The acrylic acid production and purification apparatus according to claim 1, characterized in that, The inlet of the extraction tower (3) is connected to the bottom outlet of the stirrer (2). The top of the extraction tower (3) is provided with an organic phase outlet that is connected to the top of the solvent separation tower (4). The bottom of the extraction tower (3) is provided with a residual phase outlet that is connected to the extraction recovery mechanism (5).

4. An acrylic acid production and purification apparatus according to claim 1, characterized in that, The extraction and recovery mechanism (5) is equipped with a fractionation system. The extraction and recovery mechanism (5) is equipped with an extractant outlet and a wastewater outlet. The extractant outlet is fixedly connected to the extraction tower (3).

5. An acrylic acid production and purification apparatus according to claim 4, characterized in that, The top of the solvent separation tower (4) is connected to the extractant outlet of the extraction and recovery mechanism (5), and the bottom outlet of the solvent separation tower (4) is connected to the inlet of the acetic acid recovery tower (6).

6. An acrylic acid production and purification apparatus according to claim 1, characterized in that, The acetic acid recovery tower (6) includes a first recovery tower (61) and a second recovery tower (62). The first recovery tower (61) is connected to the bottom of the solvent separation tower (4), and the second recovery tower (62) is fixedly connected to the top of the first recovery tower (61). The second recovery tower (62) is provided with an acetic acid recovery port, and the bottom of the first recovery tower (61) is fixedly connected to the deweighting tower (7).

7. An acrylic acid production and purification apparatus according to claim 1, characterized in that, The top of the deweight removal tower (7) is fixedly connected to the distillation tower (8), and the bottom of the deweight removal tower (7) is provided with a heavy component discharge outlet.

8. An acrylic acid production and purification apparatus according to claim 1, characterized in that, The distillation column (8) includes a cooler (81) and a distillation column body (82). The cooler (81) is fixedly connected to the top of the heavy column (7), and the distillation column body (82) is fixedly connected to the cooler (81). The top of the distillation column body (82) is provided with a finished product outlet.

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