Device and method for recovering ethyl acetate in adhesive production process

Abstract

The invention discloses a device and method for recovering ethyl acetate in an adhesive production process, and the method comprises the following steps: carrying out layering pretreatment on waste liquid containing ethyl acetate to obtain water-phase feed liquid and oil-phase feed liquid; dehydrating the water-phase feed liquid through continuous normal-pressure rectification treatment; the dehydrated component is cooled and then layered, the layered water-phase component is used as a reflux liquid, and the oil-phase component and the oil-phase feed liquid are subjected to continuous normal-pressure rectification treatment to remove acetic acid; gasifying the deacidified solution, and dehydrating through membrane separation; and carrying out continuous normal-pressure rectification treatment on the dehydrated organic gas phase to remove ethanol light components, so as to obtain an ethyl acetate product. According to the method, layering pretreatment is combined with multi-stage rectification, membrane separation and energy collaborative optimization technologies, so that efficient recovery of ethyl acetate and green collaboration of waste liquid treatment are realized.

Description

Technical Field

[0001] The present invention belongs to the field of chemical engineering technology, and particularly relates to a device and method for recovering ethyl acetate during the production of adhesives. Background Art

[0002] During the production of adhesives, ethyl acetate is widely used as an efficient solvent in the preparation of various adhesives, including polyurethane adhesives, acrylate adhesives, rubber-based adhesives, and some epoxy resin modified adhesives. For example, when preparing polyurethane adhesives, ethyl acetate is often added to adjust the viscosity and dispersibility of the system; when preparing acrylate adhesives, ethyl acetate is often added as a solvent to promote the homogeneous reaction of monomers; rubber-based adhesives rely on ethyl acetate to dissolve rubber particles to form a uniform glue solution. However, the un-recovered ethyl acetate during the production process will be discharged in the form of volatile organic compounds (VOCs), which not only causes environmental pollution, but also leads to waste of raw materials, increases production costs, and poses potential safety hazards of explosion and fire.

[0003] Currently, the industrial recovery of ethyl acetate mainly relies on distillation, adsorption, and condensation methods. The distillation method separates ethyl acetate in the mixed solution by heating, but it has high energy consumption. And if the system contains azeotropes (such as water or alcohols), a third component needs to be introduced to break the azeotrope, resulting in a complex process and low efficiency; the adsorption method uses activated carbon or molecular sieves to adsorb ethyl acetate in the waste gas, but the adsorbent is easily saturated, requiring frequent regeneration or replacement, with high operating costs, and it is difficult to handle high-flow waste gas; the condensation method recovers gaseous ethyl acetate through low-temperature condensation, but the recovery rate drops sharply under low-concentration or high-temperature conditions, and the equipment is prone to frosting and blockage. The above methods generally have problems such as high energy consumption, low efficiency, poor adaptability, or high operation and maintenance costs, and it is particularly difficult to adapt to the waste liquid composition of the mixture of multiple solvents during the production of adhesives. Therefore, there is an urgent need to develop an efficient, economical, and adaptable device and method for recovering ethyl acetate to achieve resource recycling and meet the requirements of environmental protection and safe production. Summary of the Invention

[0004] To solve the deficiencies of the prior art, the purpose of the present invention is to provide a device and method for recovering ethyl acetate during the production of adhesives. Through hierarchical pretreatment combined with multi-stage rectification, membrane separation, and energy synergy optimization technology, the efficient recovery of ethyl acetate and the green synergy of waste liquid treatment are achieved, while reducing the emission of organic waste liquid.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions: A method for recovering ethyl acetate during the production of adhesives, comprising the following steps: S1. Perform hierarchical pretreatment on the waste liquid containing ethyl acetate to obtain an aqueous phase feed liquid and an oil phase feed liquid; S2. Dehydrate the aqueous phase feed liquid through continuous atmospheric rectification treatment; S3. After the dehydrated components are cooled, they are stratified. The stratified aqueous phase components are used as reflux liquid, and the oil phase components and the oil phase feed liquid are subjected to continuous atmospheric distillation to remove acetic acid. S4. After the solution after deacidification is vaporized, it is dehydrated through membrane module separation. S5. The dehydrated organic gas phase is subjected to continuous atmospheric distillation to remove light ethanol components, and ethyl acetate product is obtained.

[0006] Preferably, in the aforementioned step S1, the feed liquid containing ethyl acetate is generated during the production of one of polyurethane adhesives, acrylate adhesives, and rubber-based adhesives.

[0007] Preferably, in the aforementioned step S2, the number of trays of the dehydration tower for dehydration is 30 - 35, the reflux ratio is 3 - 5, and the top temperature of the tower is 70 - 75 °C; in step S3, the number of trays of the deacidification tower for removing acetic acid is 20 - 25, the reflux ratio is 2 - 3, and the top temperature of the tower is 70 - 80 °C.

[0008] Preferably, in the aforementioned step S4, the operating pressure of the membrane module is 0.8 - 1.0 MPa, and the water content of the dehydrated organic phase < 0.1%; in step S5, the number of trays of the refining tower for removing ethanol is 25 - 30, the reflux ratio is 4 - 5, and the top temperature of the tower is 75 - 78 °C.

[0009] A recovery device for ethyl acetate during the production of adhesives, comprising: A dehydration tower for dehydrating the aqueous phase feed liquid; A stratifier connected to the top of the dehydration tower for stratifying the condensate of the components at the top of the dehydration tower; A deacidification tower connected to the bottom discharge port of the stratifier for removing acetic acid from the stratified oil phase components and the oil phase feed liquid; A membrane module connected to the top of the deacidification tower for dehydration treatment; A refining tower connected to the top of the membrane module for removing light ethanol components from the feed liquid to obtain ethyl acetate product.

[0010] Preferably, it further includes an aqueous phase feed liquid pipeline connected to the feed port of the dehydration tower for transporting the aqueous phase feed liquid to the dehydration tower.

[0011] Preferably, it further includes a preheater connected between the aqueous phase feed liquid pipeline and the dehydration tower for preheating the aqueous phase feed liquid.

[0012] Preferably, it further includes an oil phase feed liquid pipeline connected to the feed port of the deacidification tower for transporting the oil phase feed liquid to the deacidification tower.

[0013] Preferably, an evaporator is further included, which is connected between the deacidification tower and the membrane module and is used for vaporizing the solution at the top of the deacidification tower.

[0014] Preferably, a membrane module condenser is further included, which is connected to the bottom of the membrane module and is used for condensing the water permeating through the membrane into recycled water and returning it to the dehydration tower for further dehydration.

[0015] Preferably, an acetic acid treatment unit is further included, which is connected to the bottom of the deacidification tower and is used for recovering acetic acid; the acetic acid treatment unit includes: A cooler, which is connected to the outlet at the bottom of the deacidification tower and is used for cooling the waste liquid at the bottom of the deacidification tower; A neutralization reactor, which is connected to the outlet of the cooler and is used for carrying out a neutralization reaction between the waste liquid at the bottom of the deacidification tower and the alkali solution to generate an acetate solution; An evaporation concentrator, which is connected to the outlet of the neutralization reactor and is used for carrying out a vacuum evaporation concentration treatment on the acetate solution; A crystallization kettle, which is connected to the concentrated liquid outlet of the evaporation concentrator and is used for cooling the concentrated liquid and precipitating acetate crystals; A centrifuge, which is connected to the bottom of the crystallization kettle and is used for separating the acetate crystals from the mother liquor to obtain a solid acetate product.

[0016] Preferably, the centrifuge is connected to the neutralization reactor through a reflux pipeline and is used for sending the mother liquor separated by centrifugation to the neutralization reactor to realize the recycling of the mother liquor.

[0017] The advantages of the present invention are as follows: (1) Through the hierarchical pretreatment combined with multi-stage rectification, membrane separation and energy synergy optimization technology, the present invention realizes the efficient recovery of ethyl acetate and the green synergy of waste liquid treatment; through the multi-stage energy recovery design in the whole process, the steam consumption and energy consumption cost are significantly reduced, and at the same time, the discharge of organic waste liquid is reduced. The overall process has the technical advantages of high resource recovery efficiency, strong environmental friendliness and low energy consumption, providing an economically feasible solution for the recycling of organic solvents in adhesive production; (2) After the waste liquid is divided into an aqueous phase and an oil phase through hierarchical pretreatment in the process of the present invention, the dehydration treatment is preferentially carried out on the aqueous phase to efficiently remove a large amount of water and low-boiling azeotropes, thereby avoiding the problem of increased energy consumption caused by the interference of the aqueous phase during the dehydration stage of the high-concentration organic matter in the oil phase, and at the same time reducing the material treatment load of the subsequent deacidification tower; the light-component organic matter separated in the aqueous phase pretreatment stage and the azeotropic effect of the subsequent deacidification tower act synergistically, enabling acetic acid to be enriched in the bottom waste liquid, reducing the interference to the product purity; (3) The membrane dehydration process of the present invention deeply dehydrates the light-component organic phase, breaks through the limitation of water residue in traditional rectification, and realizes the dual effects of recycled water utilization and organic phase purification; (4) The present invention provides an acetic acid treatment unit at the bottom of the deacidification tower, which converts the high-concentration acetic acid waste liquid discharged from the bottom of the deacidification tower into acetate crystals, achieving resource utilization and reducing the treatment difficulty of acidic waste liquid and environmental pollution. Description of the Drawings

[0018] Figure 1 is the process flow diagram of the present invention.

[0019] The meanings of the reference numerals in the drawings: 1, dehydration tower; 2, layer separator; 3, deacidification tower; 4, membrane module; 5, refining tower; 6, preheater; 7, aqueous phase feed liquid pipeline; 8, oil phase feed liquid pipeline; 9, evaporator; 10, membrane module condenser; 11, cooler; 12, neutralization reactor; 13, evaporation concentrator; 14, crystallization kettle; 15, centrifuge; 16, reflux pipeline. Detailed Embodiments

[0020] The present invention will be specifically introduced below in conjunction with the drawings and specific embodiments.

[0021] See Figure 1 , a recovery device for ethyl acetate in the production process of an adhesive of the present invention, comprising: a dehydration tower 1 for dehydrating the aqueous phase feed liquid; a layer separator 2 connected to the top of the dehydration tower 1 for separating the condensate of the components at the top of the dehydration tower 1; a deacidification tower 3 connected to the bottom discharge port of the layer separator 2 for removing acetic acid from the separated oil phase components and the oil phase feed liquid; a membrane module 4 connected to the top of the deacidification tower 3 for dehydration treatment; a refining tower 5 connected to the top of the membrane module 4 for removing the light ethanol components in the feed liquid to obtain ethyl acetate products.

[0022] It further includes an aqueous phase feed liquid pipeline 7 connected to the feed port of the dehydration tower 1 for transporting the aqueous phase feed liquid to the dehydration tower 1. It further includes a preheater 6 connected between the aqueous phase feed liquid pipeline 7 and the dehydration tower 1 for preheating the aqueous phase feed liquid. It further includes an oil phase feed liquid pipeline 8 connected to the feed port of the deacidification tower 3 for transporting the oil phase feed liquid to the deacidification tower 3. It further includes an evaporator 9 connected between the deacidification tower 3 and the membrane module 4 for vaporizing the solution at the top of the deacidification tower 3. It further includes a membrane module condenser 10 connected to the bottom of the membrane module 4 for condensing the water permeating through the membrane into recycled water and returning it to the dehydration tower 1 for further dehydration.

[0023] It further includes an acetic acid treatment unit connected to the bottom of the deacidification tower 3 for recovering acetic acid. The acetic acid treatment unit includes: a cooler 11 connected to the bottom outlet of the deacidification tower 3 for cooling the waste liquid at the bottom of the deacidification tower 3; a neutralization reactor 12 connected to the outlet of the cooler 11 for carrying out a neutralization reaction between the waste liquid at the bottom of the deacidification tower 3 and an alkali solution to generate an acetate solution; an evaporation concentrator 13 connected to the outlet of the neutralization reactor 12 for carrying out a vacuum evaporation concentration treatment on the acetate solution; a crystallization kettle 14 connected to the concentrated liquid outlet of the evaporation concentrator 13 for cooling the concentrated liquid and precipitating acetate crystals; a centrifuge 15 connected to the bottom of the crystallization kettle 14 for separating the acetate crystals from the mother liquor to obtain a solid acetate product. The centrifuge 15 is connected to the neutralization reactor 12 through a reflux pipeline 16 for sending the mother liquor separated by centrifugation to the neutralization reactor 12 to realize the recycling of the mother liquor.

[0024] A method for recovering ethyl acetate during the production process of an adhesive according to the present invention includes the following steps: S1. Perform a layering pretreatment on the waste liquid containing ethyl acetate to obtain an aqueous phase feed liquid and an oil phase feed liquid; S2. Feed the aqueous phase feed liquid into a dehydration tower 1. The dehydration tower 1 adopts an azeotropic distillation process and continuous atmospheric distillation operation to realize the dehydration of the aqueous phase feed liquid. After the aqueous phase feed liquid exchanges heat with the hot material at the bottom of the dehydration tower 1 in a preheater 6, it is continuously fed into the dehydration tower 1 by a pump. Ethyl acetate, ethanol, and water are azeotroped to the top of the tower in the form of a ternary azeotrope, enriched as light components at the top of the tower, and enter a condenser in a vapor phase for condensation and cooling. The condensate overflows into a separator 2. The condensate is layered in the separator 2. The aqueous phase component is refluxed to the dehydration tower 1 as a reflux liquid; the oil phase component is discharged from the system and sent to the deacidification tower 3. The water after removing organic substances passes through the preheater 6 and a cooler in sequence at the bottom of the tower, and is discharged from the system as wastewater; S3. Continuously feed the layered oil phase component and the oil phase feed liquid into the deacidification tower 3 by pumps respectively for continuous deacidification. The deacidification tower 3 adopts a distillation process and continuous atmospheric distillation operation to realize the removal of residual acetic acid in the feed liquid; ethyl acetate, ethanol, and water are enriched as light components at the top of the tower. Part of the condensate is refluxed to the deacidification tower 3 as a reflux liquid, and the rest goes to a subsequent evaporator 9; High-boiling organic substances such as acetic acid are cooled by a cooler 11 at the bottom of the tower, and are continuously added to a neutralization reactor 12 in a stoichiometric ratio with a sodium hydroxide (NaOH) solution to carry out a neutralization reaction to generate an aqueous sodium acetate solution: then it is sent to an evaporation concentrator 13 to carry out vacuum evaporation on the sodium acetate solution to remove water and concentrate it to a supersaturated state; then it is sent to a crystallization kettle 14 to cool the concentrated liquid to room temperature, precipitate sodium acetate crystals, and obtain a solid sodium acetate product after centrifugal separation. The separated mother liquor is returned to the neutralization reactor 12 for reuse, reducing raw material waste; S4. The ethyl acetate solution from the top of the tower is pressurized and vaporized in the evaporator 9 and then enters the membrane module 4 for vaporization membrane dehydration. The water permeates through the membrane and condenses into regenerated water, which returns to the dehydration tower 1 for further dehydration. The dehydrated organic phase goes to the refining tower 5 in the form of gas phase for impurity removal in one step. S5. The dehydrated organic gas phase is sent into the refining tower 5. The refining tower 5 adopts a continuous distillation process and operates at atmospheric pressure to remove the residual light components such as ethanol in the feed liquid. The organic gas phase from the membrane module 4 is cooled by exchanging heat with the bottom liquid of the refining tower 5 and then continuously sent into the refining tower 5 for continuous light component removal. Ethanol, water and a small amount of ethyl acetate are enriched at the top of the tower. The condensate is partially refluxed to the refining tower 5 and partially discharged from the system as waste liquid. The high-concentration ethyl acetate product is discharged from the bottom of the tower.

[0025] Example 1. A method for recovering ethyl acetate in the production process of an adhesive, comprising the following steps: After the waste liquid containing ethyl acetate is allowed to stand and separate into layers, the aqueous phase feed liquid (90 wt% water, 9 wt% ethanol, 0.5 wt% ethyl acetate, 0.5 wt% acetic acid) is heat-exchanged with the hot material at the bottom of the dehydration tower 1 through the preheater 6 and then enters the dehydration tower 1 with 30 trays for azeotropic distillation. The light components (75% ethyl acetate, 22% ethanol, 2% water, 1% acetic acid) are condensed at a reflux ratio of 3 at the top temperature of 75 °C (ternary azeotrope composition) and enter the separator 2. The oil phase components are discharged to the deacidification tower 3. The waste water at the bottom of the tower has a water content > 99.5% after cooling and is discharged from the system. The oil phase feed liquid (2 wt% water, 97.5 wt% ethanol, 0.25 wt% ethyl acetate, 0.25 wt% acetic acid) is mixed with the oil phase components after dehydration of the aqueous phase and sent into the deacidification tower 3 with 20 trays. The light components (82% ethyl acetate, 16% ethanol, 2% water) are separated at the top temperature of 77 °C and a reflux ratio of 2. The waste liquid at the bottom of the tower contains > 98% acetic acid and is sent to the acetic acid treatment unit to obtain a solid acetate product through neutralization and crystallization. The light components are dehydrated through the membrane module 4 at a pressure of 0.8 MPa, and the water content of the organic phase < 0.1%. The organic phase enters the refining tower 5, and the residual ethanol light impurities are removed at the top temperature of 78 °C and a reflux ratio of 4. Finally, an ethyl acetate product with a purity > 99.8%, a water content < 0.05% and a yield of 98% is obtained at the bottom of the tower.

[0026] Example 2. This example adopts the same method for recovering ethyl acetate in the production process of an adhesive as in Example 1, comprising the following steps: After the waste liquid containing ethyl acetate is allowed to stand and layer, the aqueous phase feed liquid (90 wt% water, 9 wt% ethanol, 0.5 wt% ethyl acetate, 0.5 wt% acetic acid) is heat-exchanged with the hot material at the bottom of the dehydration tower 1 through the preheater 6 and then enters the dehydration tower 1 with 35 theoretical plates for azeotropic distillation. At the top temperature of 73 °C (composition of the ternary azeotrope), the light components (78% ethyl acetate, 20% ethanol, 1.5% water, 0.5% acetic acid) are condensed at a reflux ratio of 4 and enter the separator 2, and the oil-phase components are discharged to the deacidification tower 3; the waste water at the bottom of the tower has a water content > 99.6% after cooling and is discharged from the system. The oil-phase feed liquid (1.5 wt% water, 97.8 wt% ethanol, 0.3 wt% ethyl acetate, 0.4 wt% acetic acid) is mixed with the oil-phase components after dehydration of the aqueous phase and sent to the deacidification tower 3 with 25 theoretical plates. At the top temperature of 76 °C and a reflux ratio of 2.5, the light components (85% ethyl acetate, 13.5% ethanol, 1.5% water) are separated out, and the waste liquid at the bottom of the tower contains > 98.5% acetic acid and is sent to the acetic acid treatment unit, and solid acetate products are obtained by neutralization and crystallization; the light components are dehydrated through the membrane module 4 at a pressure of 1.0 MPa, and the water content of the organic phase < 0.05%; the organic phase enters the refining tower 5, and the residual ethanol light impurities are removed at the top temperature of 75 °C and a reflux ratio of 5. Finally, ethyl acetate products with a purity > 99.85%, a water content < 0.03%, and a yield of 98.5% are obtained at the bottom of the tower.

[0027] Comparative example: Directly treating the waste liquid with a single distillation column, including the following steps: The waste liquid (45 wt% water, 48 wt% ethanol, 5 wt% ethyl acetate, 2 wt% acetic acid) enters a distillation column with 40 theoretical plates and a reflux ratio of 5. The crude ethyl acetate (purity 88%, water content 3%, ethanol 7%, acetic acid 2%) is taken out at the top temperature of 80 °C, and the waste liquid containing 75% acetic acid, 20% water, and 5% other organic substances is discharged at the bottom temperature of 115 °C. Due to the azeotropic effect and impurity interference, the yield of the ethyl acetate product is 70%, and the steam consumption is 60% higher than that in Example 1, and the service life of the equipment is shortened by 40% due to high-temperature acid corrosion.

[0028] Compared with the traditional distillation method of the comparative example, in Example 1 of this patent, through the collaborative process of hierarchical pretreatment - stepwise distillation - membrane dehydration, the purity of ethyl acetate is increased from 88% to 99.8%, the yield is increased from 70% to 98%, the steam consumption is reduced by 60%, and the residual amount of organic substances in the waste water is reduced from 5% to less than 0.5%. The service life of the equipment is extended by 40%, significantly solving the defects of low separation efficiency, high energy consumption, and easy corrosion of the traditional process.

[0029] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any form. Any technical solutions obtained by using equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A method for recovering ethyl acetate during the production of adhesives, characterized in that, It includes the following steps: S1. Perform hierarchical pretreatment on the waste liquid containing ethyl acetate to obtain an aqueous phase feed liquid and an oil phase feed liquid; S2. Dehydrate the aqueous phase feed liquid through continuous atmospheric distillation; S3. After the dehydrated components are cooled, perform layering. The layered aqueous phase components are used as reflux liquid, and the oil phase components and the oil phase feed liquid are subjected to continuous atmospheric distillation to remove acetic acid; S4. After the deacidified solution is vaporized, perform dehydration treatment through membrane module separation; S5. The dehydrated organic gas phase is subjected to continuous atmospheric distillation to remove ethanol light components to obtain ethyl acetate products.

2. The method for recovering ethyl acetate during the production process of an adhesive according to claim 1, wherein In the step S1, the feed liquid containing ethyl acetate is generated during the production of one of polyurethane adhesives, acrylate adhesives, and rubber-based adhesives.

3. A method for recovering ethyl acetate during the production of an adhesive according to claim 1, characterized in that, In the step S2, the number of trays of the dehydration tower for dehydration is 30 - 35, the reflux ratio is 3 - 5, and the top temperature of the tower is 70 - 75 °C; in the step S3, the number of trays of the deacidification tower for removing acetic acid is 20 - 25, the reflux ratio is 2 - 3, and the top temperature of the tower is 70 - 80 °C.

4. The recovery method of ethyl acetate during the production process of an adhesive according to claim 1, characterized in that, In the step S4, the operating pressure of the membrane module is 0.8 - 1.0 MPa, and the water content of the dehydrated organic phase < 0.1%; in the step S5, the number of trays of the refining tower for removing ethanol is 25 - 30, the reflux ratio is 4 - 5, and the top temperature of the tower is 75 - 78 °C.

5. A recovery device for ethyl acetate in the production process of an adhesive, characterized in that, It includes: A dehydration tower for dehydrating the aqueous phase feed liquid; A layer separator connected to the top of the dehydration tower for layering the condensate of the components at the top of the dehydration tower; A deacidification tower connected to the bottom discharge port of the layer separator for removing acetic acid from the oil phase components and the oil phase feed liquid after layering; A membrane module connected to the top of the deacidification tower for performing dehydration treatment; A refining tower connected to the top of the membrane module for removing ethanol light components from the feed liquid to obtain ethyl acetate products.

6. The recovery device for ethyl acetate in the production process of an adhesive according to claim 5, characterized in that, It further includes an aqueous phase feed liquid pipeline connected to the feed port of the dehydration tower for transporting the aqueous phase feed liquid to the dehydration tower; it also includes an oil phase feed liquid pipeline connected to the feed port of the deacidification tower for transporting the oil phase feed liquid to the deacidification tower.

7. The recovery device for ethyl acetate in the production process of an adhesive according to claim 6, characterized in that, It further includes a preheater connected between the aqueous phase feed liquid pipeline and the dehydration tower for preheating the aqueous phase feed liquid.

8. The recovery device for ethyl acetate in the production process of an adhesive according to claim 5, characterized in that, It further includes an evaporator connected between the deacidification tower and the membrane module for vaporizing the solution at the top of the deacidification tower; it also includes a membrane module condenser connected to the bottom of the membrane module for condensing the water permeating through the membrane into recycled water and returning it to the dehydration tower for further dehydration.

9. The recovery device for ethyl acetate in the production process of an adhesive according to claim 5, characterized in that, It further includes an acetic acid treatment unit connected to the bottom of the deacidification tower for recovering acetic acid; the acetic acid treatment unit includes: A cooler connected to the bottom outlet of the deacidification tower for cooling the waste liquid at the bottom of the deacidification tower; A neutralization reactor connected to the outlet of the cooler for performing a neutralization reaction between the waste liquid at the bottom of the deacidification tower and the alkali solution to generate an acetate solution; An evaporation concentrator connected to the outlet of the neutralization reactor for performing vacuum evaporation concentration treatment on the acetate solution; A crystallization kettle connected to the concentrated liquid outlet of the evaporation concentrator for cooling the concentrated liquid and precipitating acetate crystals; A centrifuge connected to the bottom of the crystallization kettle for separating acetate crystals from the mother liquor to obtain solid acetate products.

10. A recovery device for ethyl acetate in the production process of an adhesive according to claim 9, characterized in that, The centrifuge is connected to the neutralization reactor through a reflux pipeline, and is used to send the mother liquor separated by centrifugation to the neutralization reactor to realize the recycling of the mother liquor.

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