An apparatus for the production of ethylene glycol

Abstract

This utility model discloses an apparatus for preparing ethylene glycol, comprising: an oxidation reactor; an absorption tower, the inlet of which is connected to the outlet of the oxidation reactor; a stripping tower, the top of which is connected to the bottom of the absorption tower; an ethylene glycol reactor, the inlet of which is connected to the top of the stripping tower; a water treatment unit, the inlet of which is connected to the bottom of the stripping tower; a multi-effect evaporation unit, including two inlets, one inlet connected to the outlet of the water treatment unit and the other inlet connected to the outlet of the ethylene glycol reactor; a dehydration tower, the inlet of which is connected to one outlet of the multi-effect evaporation unit; a condenser, the inlet of which is connected to the top of the dehydration tower, and the outlets including a gas phase outlet and a liquid phase outlet, which are connected in parallel to the top of the dehydration tower; and a transmission pipeline, the inlet of which is connected between the gas phase outlet, the liquid phase outlet and the top of the dehydration tower, and the outlet of which is connected between the bottom of the stripping tower and the inlet of the water treatment unit. The ethylene glycol preparation apparatus provided by this utility model can improve economic efficiency.

Description

Technical Field

[0001] This utility model relates to the field of ethylene glycol preparation technology, specifically to an apparatus for preparing ethylene glycol. Background Technology

[0002] Ethylene glycol, as an important basic petrochemical raw material, is widely used in polyester, polyester filament, polyester staple fiber, surfactants, printing, and antifreeze. Among these, using ethylene as a raw material to produce ethylene glycol is the most mature process and holds a dominant market position. However, in the process of producing ethylene glycol using ethylene as a raw material, the condensate from the top gas of the dehydration tower is mostly discharged directly into the wastewater pond. Because of the residual ethylene glycol in the condensate, there are problems such as ethylene glycol waste and low economic efficiency, which seriously limit the further development of this process. Utility Model Content

[0003] The purpose of this invention is to provide an apparatus for preparing ethylene glycol, which can reduce the discharge of condensate from the top of the dehydration tower, recover ethylene glycol from the condensate, and improve economic efficiency.

[0004] To achieve the above-mentioned and other related objectives, this utility model is implemented through the following technical solution.

[0005] This invention provides an apparatus for preparing ethylene glycol, comprising at least:

[0006] Oxidation reactor;

[0007] The absorption tower has its inlet connected to the outlet of the oxidation reactor;

[0008] A stripping tower, wherein the top of the stripping tower is connected to the bottom of the absorption tower;

[0009] An ethylene glycol reactor, the inlet of which is connected to the top of the stripping tower;

[0010] The water treatment unit has its inlet connected to the bottom of the stripping tower;

[0011] The multi-effect evaporation unit includes two inlets, one of which is connected to the outlet of the water treatment unit, and the other inlet is connected to the outlet of the ethylene glycol reactor.

[0012] The dehydration tower has its inlet connected to one outlet of the multi-effect evaporation unit;

[0013] The condenser has an inlet connected to the top of the dehydration tower and an outlet including a gas phase outlet and a liquid phase outlet, which are connected in parallel to the top of the dehydration tower.

[0014] A hot well water transfer pump, with its inlet connected to the outlet of the condenser and its outlet connected to the top of the dehydration tower; and

[0015] The transmission pipeline has its inlet connected to the outlet of the hot well water transfer pump, and its outlet connected between the bottom of the stripping tower and the inlet of the water treatment unit.

[0016] In one embodiment of the present invention, the preparation apparatus further includes a process water storage tank, which is disposed between the outlet of the water treatment unit and the inlet of the multi-effect evaporation unit.

[0017] In one embodiment of the present invention, the preparation apparatus further includes a vacuum jet pump, which is disposed between the gas phase outlet and the top of the dehydration tower.

[0018] In one embodiment of this utility model, another outlet of the multi-effect evaporation unit is connected to the connecting pipeline between the condenser and the vacuum jet pump.

[0019] In one embodiment of the present invention, the preparation device further includes a hot water well, which is disposed between the outlet of the vacuum jet pump and the top of the dehydration tower.

[0020] In one embodiment of the present invention, the preparation device further includes a wastewater discharge pipeline, the inlet of which is connected in parallel with the inlet of the transmission pipeline and then connected to the outlet pipeline of the hot water well.

[0021] In one embodiment of this utility model, the hot water well delivery pump is disposed between the outlet of the hot water well and the top of the dehydration tower.

[0022] In one embodiment of this utility model, the inlets of the transmission pipeline and the wastewater discharge pipeline are connected between the hot well water delivery pump and the top of the dehydration tower.

[0023] In one embodiment of the present invention, the preparation device further includes a refining unit, which is connected to the bottom of the dehydration tower.

[0024] In one embodiment of the present invention, the preparation apparatus further includes a cooler, which is disposed between the bottom of the stripping tower and the water treatment unit.

[0025] In summary, this invention provides an ethylene glycol preparation apparatus that can recover ethylene glycol from the condensate of the gas at the top of a dehydration tower, reducing condensate discharge, avoiding waste, and improving economic efficiency. Furthermore, the ethylene glycol preparation apparatus provided by this invention can reduce the amount of demineralized water used, further improving economic efficiency and facilitating large-scale application.

[0026] Of course, implementing any of the methods of this utility model does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of an apparatus for preparing ethylene glycol in one embodiment of the present invention.

[0029] Marker explanation:

[0030] 11. Oxidation reactor; 12. Absorption tower; 13. Stripping tower; 14. Pickling tower; 15. Reabsorption tower; 16. Ethylene glycol feed stripping unit; 17. Water treatment unit; 18. Process water storage tank; 19. Multi-effect evaporation unit; 20. Dehydration tower; 21. Vacuum jet pump; 22. Hot water well; 23. Condenser; 24. First reboiler; 25. Second reboiler; 26. Transfer pipeline; 27. Cooler; 28. Wastewater discharge pipeline; 29. ​​Ethylene glycol reactor; 30. Refining unit; 31. Hot well water transfer pump; 32. Air cooling. Detailed Implementation

[0031] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this utility model can be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0032] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0033] In this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used only for descriptive and distinguishing purposes and should not be construed as indicating or implying relative importance.

[0034] Please see Figure 1 As shown, this utility model provides an apparatus for preparing ethylene glycol, including, for example, an oxidation reactor 11, an absorption tower 12, a stripping tower 13, a water treatment unit 17, a multi-effect evaporation unit 19, a dehydration tower 20, a condenser 23, a transmission pipeline 26, an ethylene glycol reactor 29, and a hot well water transfer pump 31. The inlet of the absorption tower 12 is connected to the outlet of the oxidation reactor 11; the top of the stripping tower 13 is connected to the bottom of the absorption tower 12; the inlet of the ethylene glycol reactor 29 is connected to the top of the stripping tower 13; the inlet of the water treatment unit 17 is connected to the bottom of the stripping tower 13; the multi-effect evaporation unit 19 includes multiple inlets, one of which is connected to the outlet of the water treatment unit 17, and another inlet is connected to the outlet of the ethylene glycol reactor 29; the inlet of the dehydration tower 20 is connected to one outlet of the multi-effect evaporation unit 19; and the inlet of the condenser 23 is... Connected to the top of the dehydration tower 20, the outlet of the condenser 23 includes a gas phase outlet and a liquid phase outlet arranged in parallel. The gas phase outlet, vacuum jet pump 21, and hot well 22 are connected sequentially. The liquid phase outlet is directly connected to the hot well 22 (the condensate from the condenser 23 and the condensate from the vacuum jet pump 21 enter the hot well 22 simultaneously). The outlet of the hot well 22 is connected to a hot well water transfer pump 31. The inlet of the transmission pipeline 26 is connected to the outlet of the hot well water transfer pump 31, and the outlet is connected between the bottom of the stripping tower 13 and the inlet of the water treatment unit 17. In the ethylene glycol preparation apparatus provided by this utility model, by setting up the transmission pipeline 26, part of the condensate after condensation in the condenser 23 is pressurized by the hot well water transfer pump 31 and successively sent to the water treatment unit 17, the multi-effect evaporation unit 19, and the dehydration tower 20 to recover ethylene glycol in the condensate, thereby avoiding the waste caused by direct discharge of the condensate into the sewage tank and improving economic efficiency.

[0035] Please see Figure 1As shown, in one embodiment of this invention, the oxidation reactor 11 provides a site for the oxidation reaction of ethylene in the circulating gas. The circulating gas includes, for example, ethylene, oxygen, and impurity gases, such as methane, ethane, carbon dioxide, nitrogen, argon, and moisture. The circulating gas enters the oxidation reactor 11, where the ethylene is oxidized to produce ethylene oxide. Ethylene oxide, unreacted ethylene, unreacted oxygen, and the impurity gases then exit the oxidation reactor 11. During the oxidation of ethylene to produce ethylene oxide, the ethylene oxide also undergoes a side reaction with the moisture in the impurity gases to produce ethylene glycol, which leaves the oxidation reactor 11 along with the ethylene oxide, ethylene, oxygen, and impurity gases.

[0036] Please see Figure 1 As shown, in one embodiment of this invention, the inlet of the absorption tower 12 is connected to the outlet of the oxidation reactor 11. Specifically, ethylene oxide, ethylene glycol, ethylene, oxygen, and impurity gases flow from the oxidation reactor 11 into the absorption tower 12 and gradually rise to the top of the absorption tower 12. Simultaneously, absorbent enters from the top of the absorption tower 12 and descends to the bottom of the absorption tower 12, contacting the rising gas. This causes the ethylene oxide and ethylene glycol in the rising gas to dissolve in the absorbent, obtaining an ethylene oxide mixed solution, which leaves the absorption tower 12 from the bottom. Meanwhile, the ethylene, oxygen, and impurity gases in the rising gas that are not absorbed by the absorbent leave from the top of the absorption tower 12. Although the solubility of ethylene, oxygen, and impurity gases in the absorbent is very low, a small amount of ethylene, oxygen, and impurity gases still dissolve in the absorbent. Therefore, the ethylene oxide mixed solution leaving the bottom of the absorption tower 12 contains not only ethylene oxide and ethylene glycol but also a small amount of dissolved ethylene, dissolved oxygen, and dissolved impurity gases. By setting up an absorption tower 12, ethylene oxide in the circulating gas at the outlet of the oxidation reactor 11 can be absorbed, and most of the ethylene, oxygen and impurity gases can be removed.

[0037] Please see Figure 1 As shown, in one embodiment of this utility model, the top of the stripping tower 13 is connected to the bottom of the absorption tower 12. The bottom of the stripping tower 13 includes three outlets, the first of which is connected to the top of the absorption tower 12. Specifically, the ethylene oxide mixed solution at the bottom of the absorption tower 12 flows to the top of the stripping tower 13 and then descends to the bottom of the stripping tower 13. Simultaneously, stripping gas rises from the bottom of the stripping tower 13, stripping the ethylene oxide from the ethylene oxide mixed solution. The ethylene oxide and stripping gas leave from the top of the stripping tower 13, while the demineralized water in the ethylene oxide mixed solution, as well as the ethylene oxide, ethylene glycol, ethylene, oxygen, impurity gases, and ionic impurities dissolved in the demineralized water, accumulate at the bottom of the stripping tower 13, forming lean circulating water. Part of the lean circulating water enters the absorption tower 12 from the top of the absorption tower 12 as an absorbent.

[0038] Please see Figure 1 As shown, in one embodiment of this invention, a first reboiler 24 is connected to the second outlet at the bottom of the stripping tower 13 to provide stripping gas to the stripping tower 13. The inlet and outlet of the first reboiler 24 are each connected to the bottom of the stripping tower 13. Specifically, some of the lean circulating water accumulated at the bottom of the stripping tower 13 enters the first reboiler 24, where it evaporates into steam. The steam returns as stripping gas and rises to the top of the stripping tower 13 to strip the ethylene oxide in the ethylene oxide mixed solution.

[0039] Please see Figure 1 As shown, in one embodiment of this utility model, the preparation device further includes an air cooler 32, which is connected to the top of the stripping tower 13 and is used to cool the ethylene oxide and stripping gas flowing out from the top of the stripping tower 13.

[0040] Please see Figure 1 As shown, in one embodiment of this utility model, the preparation apparatus includes an acid washing tower 14, which has two inlets and two outlets. One inlet is connected to an air cooler 32, through which ethylene oxide and stripping gas, cooled by the air cooler 32, enter the acid washing tower 14 and rise to the top. The other inlet is used to replenish demineralized water into the acid washing tower 14, which acts as an absorbent to wash away impurities in the rising gas within the acid washing tower 14. One outlet is connected to a subsequently installed reabsorption tower 15. The other outlet is connected to the top of a stripping tower 13, where the demineralized water that has absorbed impurities is transported from the top of the stripping tower 13 to the bottom, where it is evaporated into stripping gas by a first reboiler 24, thereby achieving the purpose of stripping ethylene oxide. By connecting the outlet of the hot well water transfer pump 31 to the inlet of the water treatment unit 17, the liquid source at the inlet of the water treatment unit 17 can be enriched, the amount of liquid drawn from the absorption tower 13 by the water treatment unit 17 can be reduced, thereby saving the amount of liquid transferred from the pickling tower 14 to the absorption tower 13, and thus reducing the amount of demineralized water used in the pickling tower 14.

[0041] Please see Figure 1 As shown, in one embodiment of this invention, the preparation apparatus further includes a reabsorption tower 15, the inlet of which is connected to the outlet of the acid washing tower 14. Specifically, within the reabsorption tower 15, water absorbs ethylene oxide from the gas to form an ethylene oxide solution free of impurities such as ethylene and methane.

[0042] Please see Figure 1 As shown, in one embodiment of this utility model, the preparation apparatus further includes an ethylene glycol feed stripping unit 16, the inlet of which is connected to the outlet of the reabsorption tower 15. Specifically, within the ethylene glycol feed stripping unit 16, stripping gases such as steam, methane, or nitrogen strippose impurities such as carbon dioxide from the ethylene oxide solution, thereby improving the purity of the ethylene oxide solution.

[0043] Please see Figure 1 As shown, in one embodiment of this invention, the inlet of the ethylene glycol reactor 29 is connected to the outlet of the ethylene glycol feed stripping unit 16. Specifically, after the ethylene oxide solution leaves the ethylene glycol feed stripping unit 16, it enters the ethylene glycol reactor 29, where the ethylene oxide undergoes a hydration reaction to produce ethylene glycol, along with byproducts.

[0044] Please see Figure 1 As shown, in one embodiment of this utility model, the inlet of the water treatment unit 17 is connected to the third outlet at the bottom of the stripping tower 13. This allows a portion of the lean circulating water accumulated at the bottom of the stripping tower 13 to be extracted, preventing dissolved ethylene glycol, ethylene, oxygen, impurity gases, and ionic impurities in the lean circulating water from accumulating in the stripping tower 13 and affecting the purity of the ethylene oxide at the top of the stripping tower 13, as well as the purity of the ethylene glycol product. Specifically, a portion of the lean circulating water enters the water treatment unit 17, where it removes ionic impurities and ethylene oxide from the demineralized water through flash evaporation or stripping, preventing the presence of ionic impurities and ethylene oxide from affecting the operation of the subsequent multi-effect evaporation unit 19.

[0045] Please see Figure 1 As shown, in one embodiment of this invention, a cooler 27 is provided between the inlet of the water treatment unit 17 and the bottom of the stripping tower 13 to recover heat from the lean circulating water flowing from the bottom of the stripping tower 13 to the water treatment unit 17. The cooler 27 may be at least one. In this embodiment, for example, there are two coolers 27, spaced apart between the inlet of the water treatment unit 17 and the bottom of the stripping tower 13, to improve the heat recovery effect.

[0046] Please see Figure 1 As shown, in one embodiment of this invention, the multi-effect evaporation unit 19 includes two inlets and two outlets. One inlet is connected to the outlet of the water treatment unit 17, the other inlet is connected to the outlet of the ethylene glycol reactor 29, one outlet is connected to the inlet of the subsequently installed dehydration tower 20, and the other outlet is connected to the connecting pipeline between the gas phase outlet of the subsequently installed condenser 23 and the vacuum jet pump 21. Specifically, lean circulating water enters the multi-effect evaporation unit 19 from the outlet of the water treatment unit 17. The multi-effect evaporation unit 19 evaporates part of the demineralized water in the lean circulating water into gas. Ethylene glycol, dissolved ethylene, dissolved oxygen, and dissolved impurity gases in the lean circulating water are concentrated into an ethylene glycol solution, which is sent to the dehydration tower 20 from one outlet of the multi-effect evaporation unit 19. The evaporated gas, after condensation, flows from the other outlet of the multi-effect evaporation unit 19 to the connecting pipeline between the condenser 23 and the vacuum jet pump 21. By setting up the multi-effect evaporation unit 19, the processing capacity of the dehydration tower 20 can be reduced, the load on the dehydration tower 20 can be reduced, and energy consumption can be reduced.

[0047] Please see Figure 1 As shown, in one embodiment of the present invention, a process water storage tank 18 is provided between the inlet of the multi-effect evaporation unit 19 and the outlet of the water treatment unit 17 for storing lean circulating water output by the water treatment unit 17.

[0048] Please see Figure 1 As shown, in one embodiment of this invention, the inlet of the dehydration tower 20 is connected to one outlet of the multi-effect evaporation unit 19. Specifically, the ethylene glycol solution enters the dehydration tower 20 through one outlet of the multi-effect evaporation unit 19 and settles at the bottom of the dehydration tower 20. After heating, the light components in the ethylene glycol solution, such as demineralized water, dissolved ethylene, dissolved oxygen, and dissolved impurity gases, are evaporated into gases and leave from the top of the dehydration tower 20, while the ethylene glycol accumulates at the bottom of the dehydration tower 20. By setting up the dehydration tower 20, the light components such as demineralized water and ethylene glycol in the ethylene glycol solution are separated, thereby obtaining ethylene glycol with relatively high purity at the bottom of the tower.

[0049] Please see Figure 1 As shown, in one embodiment of this utility model, a second reboiler 25 is also connected to the bottom of the dehydration tower 20 to provide a heat source for the bottom of the tower, so as to evaporate the demineralized water and other light components in the ethylene glycol solution. The inlet and outlet of the second reboiler 25 are each connected to the bottom of the dehydration tower 20.

[0050] Please see Figure 1 As shown, in one embodiment of this invention, the inlet of the condenser 23 is connected to the top of the dehydration tower 20, and the outlet includes a liquid phase outlet and a gas phase outlet. The gas phase outlet and the liquid phase outlet are connected in parallel to the top of the dehydration tower 20. Specifically, after the light components such as demineralized water in the ethylene glycol solution are evaporated into gas, they enter the condenser 23 from the top of the dehydration tower 20. After being condensed into a light component solution by the condenser 23, part of the light component solution returns to the dehydration tower 20 from the liquid phase outlet as reflux liquid to maintain the mass transfer process and thermodynamic balance in the dehydration tower 20, while the uncondensed gas enters the vacuum jet pump 21 from the gas phase outlet.

[0051] Please see Figure 1 As shown, in one embodiment of this utility model, a vacuum jet pump 21 is provided between the outlet of the condenser 23 and the dehydration tower 20 for further condensing the gas at the gas phase outlet of the condenser 23.

[0052] Please see Figure 1As shown, in one embodiment of this utility model, the preparation device further includes a hot water well 22, the inlet of which is connected to the outlet of a vacuum jet pump 21. Specifically, the gas phase outlet of the condenser 23 and the vacuum jet pump 21 are connected in series, and then connected in parallel with the liquid phase outlet of the condenser 23 to the hot water well 22. Further, the preparation device also includes a hot well water transfer pump 31, the inlet of which is connected to the outlet of the hot water well 22, and the outlet is connected to the top of the dehydration tower 20.

[0053] Please see Figure 1 As shown, in one embodiment of this utility model, the preparation device further includes a wastewater discharge pipeline 28. The inlet of the wastewater discharge pipeline 28 is connected to the outlet of the hot well water transfer pump 31, and the outlet is connected to a sewage tank. Since the light component solution contains not only demineralized water but also impurities such as aldehydes and acids, by setting up the wastewater discharge pipeline 28, a portion of the light component solution is discharged into the sewage tank, preventing impurities from accumulating in the dehydration tower 20 and affecting the purity of the ethylene glycol at the top of the dehydration tower 20.

[0054] Please see Figure 1 As shown, in one embodiment of this utility model, the inlet of the transmission pipeline 26 is connected to the outlet of the hot well water transfer pump 31, and the outlet is connected to the connecting pipeline between the bottom of the stripping tower 13 and the inlet of the water treatment unit 17. Further, in this embodiment, the transmission pipeline 26 and the wastewater discharge pipeline 28 are connected in parallel, the inlet of the transmission pipeline 26 is connected to the outlet of the hot well water transfer pump 31, and the outlet is connected to the connecting pipeline between the outlet of the cooler 27 and the inlet of the water treatment unit 17. Specifically, in the dehydration tower 20, the gas flowing out from the top of the tower inevitably carries ethylene glycol. Therefore, the light component solution stored in the hot water well 22 must contain ethylene glycol. If a portion of the light component solution stored in the hot water well 22 is directly discharged into the sewage tank through the wastewater discharge pipe 28, it will inevitably lead to a waste of ethylene glycol. Therefore, by setting up a transmission pipe 26, a portion of the light component solution that would otherwise be discharged through the wastewater discharge pipe 28 is successively led to the water treatment unit 17, the process water storage tank 18, the multi-effect evaporation unit 19, and the dehydration tower 20 to recover the ethylene glycol in the light component solution. This reduces the flow rate of the light component solution directly discharged into the sewage tank, avoids the waste of ethylene glycol, and increases economic efficiency. Moreover, by setting up the transmission pipe 26, the water storage capacity in the process water storage tank 18 can be increased, thereby facilitating a reduction in the makeup water volume of the process water storage tank 18 and its associated systems, further saving on the amount of demineralized water to be replenished.

[0055] Please see Figure 1As shown, in one embodiment of this invention, the preparation apparatus further includes a refining unit 30, the inlet of which is connected to the bottom of the dehydration tower 20. Specifically, the refining unit 30 separates the material flowing out from the bottom of the dehydration tower 20 to separate ethylene glycol product. The refining unit 30 may be, for example, a distillation tower.

[0056] In summary, this invention provides an ethylene glycol preparation apparatus. By setting up a transmission pipeline to sequentially guide a portion of the condensate from the top gas of the dehydration tower to the water treatment unit, the multi-effect evaporation unit, and the dehydration tower, ethylene glycol in the condensate can be recovered, reducing the amount of condensate discharged, avoiding waste, and improving economic efficiency. Furthermore, the ethylene glycol preparation apparatus provided by this invention can reduce the amount of demineralized water used, further improving economic efficiency and facilitating large-scale application.

[0057] Throughout this specification, the terms "one embodiment," "an embodiment," or "a specific embodiment" refer to a particular feature, structure, or characteristic described in connection with an embodiment, which is included in at least one embodiment of the present invention, but not necessarily in all embodiments. Therefore, the various representations of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout the specification do not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic of any specific embodiment of the present invention may be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the present invention described and illustrated herein may be based on the teachings herein and will be considered part of the spirit and scope of the present invention.

[0058] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features. It should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application. Except for the technical features described in the specification, the remaining technical features are known to those skilled in the art. To highlight the innovative features of this utility model, the remaining technical features will not be described further here.

Claims

1. An apparatus for the production of ethylene glycol, characterized in that At least including: Oxidation reactor; The absorption tower has its inlet connected to the outlet of the oxidation reactor; A stripping tower, wherein the top of the stripping tower is connected to the bottom of the absorption tower; An ethylene glycol reactor, with its inlet connected to the top of the stripping tower; The water treatment unit has its inlet connected to the bottom of the stripping tower; The multi-effect evaporation unit includes two inlets, one of which is connected to the outlet of the water treatment unit, and the other inlet is connected to the outlet of the ethylene glycol reactor. The dehydration tower has its inlet connected to one outlet of the multi-effect evaporation unit; The condenser has an inlet connected to the top of the dehydration tower and an outlet including a gas phase outlet and a liquid phase outlet, which are connected in parallel to the top of the dehydration tower. A hot well water transfer pump has its inlet connected to the outlet of the condenser and its outlet connected to the top of the dehydration tower. as well as The transmission pipeline has its inlet connected to the outlet of the hot well water transfer pump, and its outlet connected between the bottom of the stripping tower and the inlet of the water treatment unit.

2. The preparation device according to claim 1, characterized in that The preparation apparatus further includes a process water storage tank, which is disposed between the outlet of the water treatment unit and the inlet of the multi-effect evaporation unit.

3. The preparation device according to claim 1, characterized in that The preparation apparatus further includes a vacuum jet pump, which is disposed between the gas phase outlet and the top of the dehydration tower.

4. The preparation device according to claim 3, characterized in that Another outlet of the multi-effect evaporator unit is connected to the connecting pipeline between the condenser and the vacuum jet pump.

5. The preparation device according to claim 3, characterized in that The preparation apparatus also includes a hot water well, which is located between the outlet of the vacuum jet pump and the top of the dehydration tower.

6. The preparation apparatus according to claim 5, characterized in that, The preparation device also includes a wastewater discharge pipeline, the inlet of which is connected in parallel with the inlet of the transmission pipeline and then connected to the outlet pipeline of the hot water well.

7. The preparation apparatus according to claim 6, characterized in that, The hot water well delivery pump is located between the outlet of the hot water well and the top of the dehydration tower.

8. The preparation apparatus according to claim 7, characterized in that, The inlets of the transmission pipeline and the wastewater discharge pipeline are connected between the hot well water delivery pump and the top of the dehydration tower.

9. The preparation apparatus according to claim 1, characterized in that, The preparation apparatus further includes a refining unit, which is connected to the bottom of the dehydration tower.

10. The preparation apparatus according to claim 1, characterized in that, The preparation apparatus also includes a cooler, which is disposed between the bottom of the stripping tower and the water treatment unit.

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