Separation device for ethyl acetate and butanone

Abstract

The utility model belongs to the technical field of separation, and particularly relates to an ethyl acetate and butanone separation device, which comprises a butanone separation tower, an ethanol separation tower and an ethyl acetate separation tower which are connected in sequence, in the utility model, the tower top produced liquid of the ethyl acetate separation tower returns to the butanone separation tower, so that the purity of the product can be further improved; the gas phase of the butanone separating tower is used as a heat source of a reboiler at the bottom of the ethyl acetate separating tower, the gas phase at the top of the ethyl acetate separating tower is used as a heat source of a reboiler at the bottom of the ethanol separating tower, heat coupling can be realized between the rectifying towers with different operating pressures, the energy consumption in the rectifying and separating process is further reduced, and the method has higher operability.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the separation technical field especially relates to a separation device of ethyl acetate and butanone. BACKGROUND

[0002] Ethyl acetate and butanone are both common organic solvents, and are widely used in dye, paint, detergent, pharmaceutical and other industries. Ethyl acetate and butanone are azeotropic and mutually soluble, and cannot be separated by direct rectification or pressure rectification.

[0003] The prior art proposes the idea of using ethylene glycol, DMSO, NMP and the like as extractant for extractive rectification to separate ethyl acetate and butanone, but the separation effect is not ideal, the energy consumption of the rectification separation process is large, and the heat coupling efficiency and product purity need to be improved. SUMMARY

[0004] In view of the above deficiencies of the prior art, the utility model aims to provide a separation device of ethyl acetate and butanone, to improve the separation effect and reduce the energy consumption.

[0005] To achieve the above purpose, the technical scheme adopted is:

[0006] The utility model provides a separation device of ethyl acetate and butanone, mainly including butanone separation tower, ethanol separation tower and ethyl acetate separation tower connected in sequence.

[0007] Further, the butanone separation column is provided with a material inlet, and a reboiler is connected to the bottom of the column. The bottom of the ethyl acetate separation column is connected with a second heat-coupled reboiler, the top of the butanone separation column is connected with the second heat-coupled reboiler, the second heat-coupled reboiler is respectively connected with a first trap and a first reflux tank, the first trap is connected with the first reflux tank, the first reflux tank is connected with a first reflux pump, the first reflux pump is respectively connected with the top of the butanone separation column and the middle of the ethanol separation column, the bottom of the butanone separation column is connected with a first bottom circulating material pump, the first bottom circulating material pump is connected with a butanone product outlet, the top of the ethanol separation column is sequentially connected with a second trap and a second reflux tank, the second reflux tank is connected with a second reflux pump, the second reflux pump is respectively connected with the top of the ethanol separation column and the middle of the ethyl acetate separation column, the bottom of the ethanol separation column is respectively connected with a first heat-coupled reboiler and a second bottom circulating material pump, the second bottom circulating material pump is respectively connected with the first heat-coupled reboiler and an ethanol product outlet, the top of the ethyl acetate separation column is connected with the first heat-coupled reboiler, the first heat-coupled reboiler is respectively connected with a third trap and a third reflux tank, the third trap and the third reflux tank are connected, the third reflux tank is connected with a third reflux pump, the third reflux pump is respectively connected with the top of the ethyl acetate separation column and the material inlet of the butanone separation column, the bottom of the ethyl acetate separation column is connected with a third bottom circulating material pump, and the third bottom circulating material pump is respectively connected with the second heat-coupled reboiler and an ethyl acetate product outlet.

[0008] The first trap is connected with a first waste gas outlet, the second trap is connected with a second waste gas outlet, and the third trap is connected with a third waste gas outlet.

[0009] Further, the method for using the device comprises the following steps:

[0010] The butanone separation column operates under pressure, the butanone-ethyl acetate-ethanol mixture to be treated enters the middle of the butanone separation column, the first top of the butanone separation column continuously discharges liquid into the ethanol separation column, and the butanone product is continuously discharged from the bottom of the butanone separation column; the ethanol separation column operates under negative pressure, the second top of the ethanol separation column continuously discharges liquid into the ethyl acetate separation column, and the ethanol product is continuously discharged from the bottom of the ethanol separation column; the ethyl acetate separation column operates under normal pressure, the third top of the ethyl acetate separation column returns liquid to the butanone separation column, and the ethyl acetate product is continuously discharged from the bottom of the ethyl acetate separation column.

[0011] Further, the method for using the device comprises the following steps:

[0012] The operating pressure of the butanone separation tower is pressurized. The butanone-ethyl acetate-ethanol mixture to be treated enters the middle part of the butanone separation tower from the material inlet. Under the pressurized condition, steam is used as the heat source to indirectly heat through the reboiler. The first overhead gas phase generated after heating is used as the heat source to heat the second heat-coupled reboiler of the ethyl acetate separation tower. The first heat-exchanged gas-liquid mixture obtained is divided into two parts. One part is the first condensate, and the other part is the first uncondensed gas phase. The first uncondensed gas phase is condensed through the first trap. The first condensed liquid phase obtained and the first condensate are fed into the first reflux tank together and are forced to reflux and extracted by the first reflux pump. The first reflux liquid returns to the top of the butanone separation tower. The first overhead extraction liquid is continuously fed into the middle part of the ethanol separation tower. The first bottom liquid of the butanone separation tower is continuously extracted by the first bottom circulating material pump to obtain butanone products.

[0013] The operating pressure of the ethanol separation tower is negative pressure. The heat source comes from the third overhead gas phase of the ethyl acetate separation tower. The second bottom liquid of the ethanol separation tower is heat-exchanged with the third overhead gas phase in the first heat-coupled reboiler. The gaseous mixture components of the second overhead gas phase are condensed and cooled through the second trap. The second condensed liquid phase obtained is fed into the second reflux tank and is forced to reflux and extracted by the second reflux pump. The second reflux liquid obtained returns to the ethanol separation tower. The second overhead extraction liquid is continuously fed into the middle part of the ethyl acetate separation tower. The second bottom liquid of the ethanol separation tower is continuously extracted by the second bottom circulating material pump to obtain ethanol products.

[0014] The operating pressure of the ethyl acetate separation tower is normal pressure. The heat source comes from the first overhead gas phase of the butanone separation tower. The first overhead gas phase is heat-exchanged with the third bottom liquid of the ethyl acetate separation tower in the second heat-coupled reboiler. The third bottom liquid is vaporized by heat. The third overhead gas phase generated is heat-exchanged with the first heat-coupled reboiler at the bottom of the ethanol separation tower. The second heat-exchanged gas-liquid mixture is divided into two parts. One part is the second condensate, and the other part is the second uncondensed gas phase. The second uncondensed gas phase is condensed into the third condensed liquid phase through the third trap. The third condensed liquid phase is fed into the third reflux tank together with the second condensate and is forced to reflux and extracted by the third reflux pump. The third reflux liquid returns to the top of the ethyl acetate separation tower. The third overhead extraction liquid returns to the material inlet of the middle part of the butanone separation tower. The third bottom liquid of the ethyl acetate separation tower is continuously extracted by the third bottom circulating material pump to obtain ethyl acetate products.

[0015] Further, the operating pressure of the butanone separation tower is 400-700 kPaG, the theoretical plate number is 40-80, and the reflux ratio is 3-15.

[0016] Further, the operating pressure of the ethanol separation tower is 30-70 kPaA, the theoretical plate number is 20-60, and the reflux ratio is 1-5.

[0017] Further, the ethyl acetate separation tower has 30-80 theoretical plates and a reflux ratio of 2-10.

[0018] Compared with the prior art, the utility model has the advantages of:

[0019] In the utility model, the ethyl acetate separation tower top production returns to the butanone separation tower, which can further improve the purity of the product; the butanone separation tower gas phase is used as the heat source of the ethyl acetate separation tower bottom reboiler, and the ethyl acetate separation tower top gas phase is used as the heat source of the ethanol separation tower bottom reboiler, so that heat coupling between the rectification towers with different operating pressures can be realized, thereby further reducing the energy consumption of the rectification separation process, and the utility model has high operability. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The utility model relates to a kind of process flow diagram of ethyl acetate and butanone separation device;

[0021] Figure 2 It is ternary phase diagram under normal pressure condition;

[0022] Figure 3 It is ternary phase diagram under 600kPaA condition;

[0023] Figure 4 It is ternary phase diagram under 50kPaA condition;

[0024] The drawing mark is: 11, butanone separation tower;12, reboiler;13, first trap;14, first reflux tank;15, first tower bottom circulating material pump;16, first reflux pump;17, first waste gas outlet;21, ethanol separation tower;22, first heat coupling reboiler;23, second trap;24, second reflux tank;25, second tower bottom circulating material pump;26, second reflux pump;27, second waste gas outlet;31, ethyl acetate separation tower;32, second heat coupling reboiler;33, third trap;34, third reflux tank;35, third tower bottom circulating material pump;36, third reflux pump;37, third waste gas outlet;111, to be processed butanone-ethyl acetate-ethanol mixture;112, first tower top gas phase;113, first condensed liquid phase;114, first reflux liquid;115, first tower top production;116, first heat-exchanged gas-liquid mixture;117, first tower bottom liquid;118, first uncondensed gas phase;119, first condensate;212, second tower top gas phase;213, second condensed liquid phase;214, second reflux liquid;215, second tower top production;216, second tower bottom liquid;312, third tower top gas phase;313, third condensed liquid phase;314, third reflux liquid;315, third tower top production;316, second heat-exchanged gas-liquid mixture;317, third tower bottom liquid;318, second uncondensed gas phase;319, second condensate. DETAILED DESCRIPTION

[0025] The utility model is described below in combination with examples, and the examples are only used to explain the utility model and are not used to limit the scope of the utility model.

[0026] Referring to Figure 1 The device comprises three sets of rectifying columns, namely butanone separation column 11, ethanol separation column 21 and ethyl acetate separation column 31.

[0027] The butanone separation column 11 is provided with a material inlet, and a reboiler 12 is connected to the bottom of the column; the ethyl acetate separation column 31 is connected with a second heat-coupled reboiler 32 at the bottom; the top of the butanone separation column 11 is connected with the second heat-coupled reboiler 32; the second heat-coupled reboiler 32 is connected with a first trap 13 and a first reflux tank 14 respectively; the first trap 13 is connected with the first reflux tank 14; the first reflux tank 14 is connected with a first reflux pump 16; the first reflux pump 16 is connected with the top of the butanone separation column 11 and the middle part of the ethanol separation column 21 respectively; the bottom of the butanone separation column 11 is connected with a first bottom circulating material pump 15; the first bottom circulating material pump 15 is connected with a butanone product outlet; the top of the ethanol separation column 21 is connected with a second trap 23 and a second reflux tank 24 in sequence; the second reflux tank 24 is connected with a second reflux pump 26; the second reflux pump 26 is connected with the top of the ethanol separation column 21 and the middle part of the ethyl acetate separation column 31 respectively; the bottom of the ethanol separation column 21 is connected with a first heat-coupled reboiler 22 and a second bottom circulating material pump 25 respectively; the second bottom circulating material pump 25 is connected with the first heat-coupled reboiler 22 and an ethanol product outlet respectively; the top of the ethyl acetate separation column 31 is connected with the first heat-coupled reboiler 22; the first heat-coupled reboiler 22 is connected with a third trap 33 and a third reflux tank 34 respectively; the third trap 33 and the third reflux tank 34 are connected; the third reflux tank 34 is connected with a third reflux pump 36; the third reflux pump 36 is connected with the top of the ethyl acetate separation column 31 and the material inlet in the column of the butanone separation column 11 respectively; the bottom of the ethyl acetate separation column 31 is connected with a third bottom circulating material pump 35; the third bottom circulating material pump 35 is connected with the second heat-coupled reboiler 32 and an ethyl acetate product outlet respectively.

[0028] The first trap 13 is connected with a first waste gas outlet 17; the second trap 23 is connected with a second waste gas outlet 27; and the third trap 33 is connected with a third waste gas outlet 37.

[0029] The operating pressure of the butanone separation column 11 is pressurized. The butanone-ethyl acetate-ethanol mixture 111 to be treated enters the middle of the butanone separation column 11 from the material inlet. Under pressurized conditions, the first column top gas phase 112 generated after heating by the indirect heating of the butanone separation column 11 by the reboiler 12 is used as a heat source to heat the second heat-coupled reboiler 32 of the ethyl acetate separation column 31. The first heat-exchanged gas-liquid mixture 116 obtained after heating is divided into two parts. One part is the first condensed liquid 119, and the other part is the first uncondensed gas phase 118. The first uncondensed gas phase 118 is condensed by the first trap 13. The first condensed liquid phase 113 obtained after condensation and the first condensed liquid 119 enter the first reflux tank 14 together and are forced to reflux and extracted by the first reflux pump 16. The first reflux liquid 114 returns to the top of the butanone separation column 11. The first column top extraction liquid 115 is continuously introduced into the middle of the ethanol separation column 21. The first column bottom liquid 117 of the butanone separation column 11 is continuously extracted by the first column bottom circulating material pump 15 to obtain butanone products.

[0030] The operating pressure of the ethanol separation column 21 is negative pressure. The heat source of the ethanol separation column 21 comes from the third column top gas phase 312 of the ethyl acetate separation column 31. The second column bottom liquid 216 of the ethanol separation column 21 is heat-exchanged with the third column top gas phase 312 in the first heat-coupled reboiler 22. After the gaseous mixture components of the second column top gas phase 212 are vaporized by heating, the second column top gas phase 212 is condensed and cooled by the second trap 23. The second condensed liquid phase 213 obtained after condensation enters the second reflux tank 24 and is forced to reflux and extracted by the second reflux pump 26. The second reflux liquid 214 returns to the ethanol separation column 21. The second column top extraction liquid 215 is continuously introduced into the middle of the ethyl acetate separation column 31. The second column bottom liquid 216 of the ethanol separation column 21 is continuously extracted by the second column bottom circulating material pump 25 to obtain ethanol products.

[0031] The operating pressure of the ethyl acetate separation column 31 is atmospheric pressure. The heat source of the ethyl acetate separation column 31 comes from the first column top gas phase 112 of the butanone separation column 11. The first column top gas phase 112 is heat-exchanged with the third column bottom liquid 317 of the ethyl acetate separation column 31 in the second heat-coupled reboiler 32. The third column bottom liquid 317 is vaporized by heating. The third column top gas phase 312 generated after vaporization is heat-exchanged with the first heat-coupled reboiler 22 at the bottom of the ethanol separation column 21. The second heat-exchanged gas-liquid mixture 316 is divided into two parts. One part is the second condensed liquid 319, and the other part is the second uncondensed gas phase 318. The second uncondensed gas phase 318 is condensed into the third condensed liquid phase 313 by the third trap 33. The third condensed liquid phase 313 and the second condensed liquid 319 enter the third reflux tank 34 together and are forced to reflux and extracted by the third reflux pump 36. The third reflux liquid 314 returns to the top of the ethyl acetate separation column 31. The third column top extraction liquid 315 returns to the material inlet in the middle of the butanone separation column 11. The third column bottom liquid 317 of the ethyl acetate separation column 31 is continuously extracted by the third column bottom circulating material pump 35 to obtain ethyl acetate products.

[0032] As a preferred embodiment, the butanone separation tower 11 described in the utility model has an operating pressure of 400-700 kPaG, a theoretical plate number of 40-80, and a reflux ratio of 3-15.

[0033] As a preferred embodiment, the ethanol separation tower 21 described in the utility model has an operating pressure of 30-70 kPaA, a theoretical plate number of 20-60, and a reflux ratio of 1-5.

[0034] As a preferred embodiment, the ethyl acetate separation tower 31 described in the utility model has an operating pressure of normal pressure, a theoretical plate number of 30-80, and a reflux ratio of 2-10.

[0035] Example: the butanone-ethyl acetate-ethanol mixture 111 to be treated has a flow rate of 1000 kg / h, and a composition of ethyl acetate 31.7%, butanone 37.5%, and ethanol 30.8%; the butanone separation tower 11 has an operating pressure of 500 kPaG, a theoretical plate number of 80, an operating reflux ratio of 6, a tower bottom temperature of 147.2℃, a butanone content in the tower bottom product of 99.5%, a product flow rate of 377 kg / h, a tower top temperature of 132.5℃, a tower top product flow rate of 3460 kg / h, a composition of ethyl acetate 59.2%, butanone 10.6%, and ethanol 30.2%, and the tower top product enters the ethanol separation tower 21; the ethanol separation tower 21 has an operating pressure of 50 kPaA, a theoretical plate number of 50, an operating reflux ratio of 3, a tower bottom temperature of 61.5℃, an ethanol content in the tower bottom product of 99.9%, a product flow rate of 308 kg / h, a tower top temperature of 53.5℃, a tower top product flow rate of 3152 kg / h, a composition of ethyl acetate 65%, butanone 11.6%, and ethanol 23.4%, and the tower top product enters the ethyl acetate separation tower 31; the ethyl acetate separation tower 31 has an operating pressure of normal pressure, a theoretical plate number of 60, an operating reflux ratio of 5, a tower bottom temperature of 76.8℃, an ethyl acetate content in the tower bottom product of 99.5%, a product flow rate of 315 kg / h, a tower top temperature of 72℃, a tower top product flow rate of 2837 kg / h, a composition of ethyl acetate 61.2%, butanone 12.9%, and ethanol 25.9%, and the tower top product returns to the butanone separation tower 11.

[0036] As Figure 2As shown, under normal pressure, the components in the ternary mixture of ethanol / ethyl acetate / butanone form three binary azeotropic compounds in each pair. Since the azeotropic temperature of ethanol / ethyl acetate is lower than the boiling point of ethanol and is also the lowest among the three azeotropic compounds, the two rectification boundary lines divide the residual curve into three rectification regions. Among the three azeotropic compounds, the binary azeotrope formed by ethanol / ethyl acetate is the most sensitive to pressure changes. Therefore, operating in the upper right rectification region allows for the extraction of ethyl acetate from the bottom and the azeotrope of the other two components from the top. Operating in the lower right and lower left rectification regions results in excessive clamping, making effective separation difficult.

[0037] like Figure 3 As shown, when the pressure increases from atmospheric pressure to 600 kPa, the azeotropic composition of ethanol / ethyl acetate changes, and the clamping phenomenon at the distillation boundary is significantly alleviated. Therefore, operating in the distillation zone on the lower right side, the distillation method can obtain methyl ethyl ketone from the bottom of the column and the azeotrope of the other two components from the top of the column.

[0038] like Figure 4 As shown, when the pressure changes to 50 kPa, the azeotropic composition of ethanol / ethyl acetate changes. When operating in the rectification zone on the lower left, ethanol can be obtained from the bottom of the column and the azeotrope of the other two components can be obtained from the top of the column.

[0039] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An apparatus for separating ethyl acetate from butanone, characterized by comprising: The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37). The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37). The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37). The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37).

2. The apparatus for separating ethyl acetate and butanone according to claim 1, wherein The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37).

3. The apparatus for separating ethyl acetate and butanone according to claim 1 or 2, characterized in that, The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37).

4. The apparatus for separating ethyl acetate and butanone according to claim 3, wherein The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37).

5. The apparatus for separating ethyl acetate and butanone according to claim 1, wherein The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37). The butanone separation tower (11) is connected with the second heat-coupled reboiler (32), the first trap (13) and the first reflux tank (14), the first reflux pump (16), the first bottom circulating material pump (15), the second trap (23), the second reflux tank (24), the second reflux pump (26), the first heat-coupled reboiler (22), the third trap (33), the third reflux tank (34), the third reflux pump (36), the third bottom circulating material pump (35), the first waste gas outlet (17), the second waste gas outlet (27) and the third waste gas outlet (37).

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