Ethylene glycol dehydration regeneration process and device adopting azeotropic distillation

Abstract

The invention relates to the technical field of dehydration and regeneration methods of water-containing ethylene glycol rich liquor, in particular to an ethylene glycol dehydration and regeneration process and device adopting azeotropic distillation, in the ethylene glycol dehydration and regeneration process adopting azeotropic distillation, fuel gas is adopted as an entrainer of ethylene glycol rich liquor water, so that the boiling point of azeotrope in an ethylene glycol reboiler is reduced. Compared with an existing conventional ethylene glycol rich solution distillation regeneration process, under the condition that the same ethylene glycol barren solution regeneration concentration is achieved, the regeneration temperature is reduced by at least 30 DEG C, heating through a low-frequency electromagnetic heater can be achieved, and heating is safer and more reliable compared with heating through a traditional resistance heater; the regeneration energy consumption is reduced by about 10%, no regeneration tail gas is discharged, the VOCs discharge amount is zero, and the method has the advantage of environmental protection.

Description

Technical Field

[0001] The invention relates to the technical field of dehydration and regeneration methods for aqueous ethylene glycol rich liquid, in particular to a process and device for dehydration and regeneration of ethylene glycol using azeotropic distillation, and is suitable for the technical field of shallow cold dehydration of natural gas using JT valve throttling refrigeration or propane external cooling, and dehydrocarbonization and injection of ethylene glycol as a hydrate inhibitor. Background Art

[0002] As a clean and efficient energy source, natural gas can not only optimize the energy structure and ease the contradiction between supply and demand, but also play a very important role in improving the quality of cities, improving the environment, improving people's quality of life and achieving sustainable development. Natural gas extracted from gas fields usually needs to be treated by dehydration and dehydrogenation before being input into the finished gas pipeline network to meet the requirements of finished gas hydrocarbon and water dew point. Commonly used natural gas dehydration and dehydrogenation treatment processes include JT valve throttling refrigeration and propane external cooling, both of which require the use of ethylene glycol lean liquid with a water content of 80wt.% to 85wt.% as a hydrate inhibitor. After the ethylene glycol lean liquid is injected into the system, it absorbs water and becomes ethylene glycol rich liquid with a concentration of 60wt.% to 65wt.%. After dehydration and regeneration, the ethylene glycol rich liquid becomes 80wt.% to 85wt.% lean liquid to complete the cycle. The traditional regeneration method is to use a reboiler at the bottom of the tower to heat the regeneration distillation process. The regeneration temperature is 120°C to 135°C. The ethylene glycol rich liquid enters the top of the ethylene glycol regeneration tower for preheating, and then enters the lean-rich ethylene glycol heat exchanger to exchange heat with the lean ethylene glycol solution coming out of the bottom of the tower; it enters the flash tank for flash evaporation to remove the liquid hydrocarbons carried in the rich ethylene glycol solution; the ethylene glycol solution coming out of the flash tank is filtered and then enters the regeneration tower for regeneration, and the tail gas from the top of the ethylene glycol regeneration tower is discharged into the air. The existing process technology has problems such as high regeneration temperature, high regeneration energy consumption, and the presence of organic hydrocarbon compounds VOCs (volatile organic substances) in the tail gas. Therefore, it is necessary to develop a new process technology that can effectively reduce the energy consumption of ethylene glycol regeneration and reduce VOCs emissions. Summary of the invention

[0003] The present invention provides an ethylene glycol dehydration regeneration process and device using azeotropic distillation, which overcomes the deficiencies of the above-mentioned prior art and can effectively solve the problems of high regeneration temperature, high regeneration energy consumption, and organic hydrocarbon compound VOCs emission in tail gas in the prior art.

[0004] One of the technical solutions of the present invention is achieved by the following measures: a dehydration and regeneration process of ethylene glycol using azeotropic distillation, which is carried out according to the following method: ethylene glycol rich liquid at a certain temperature and pressure is preheated by a glycol tower top heat exchanger, the preheated ethylene glycol rich liquid enters a lean-rich liquid heat exchanger for further heating, the heated ethylene glycol rich liquid enters an ethylene glycol regeneration tower from the top of the ethylene glycol regeneration tower, is countercurrently contacted with steam in the tower for stepwise heating and concentration, and then enters an ethylene glycol reboiler at the bottom of the ethylene glycol regeneration tower, the ethylene glycol reboiler heats the ethylene glycol rich liquid by a low-frequency electromagnetic heater to regenerate the ethylene glycol lean liquid, the regenerated ethylene glycol lean liquid flows out from the ethylene glycol reboiler liquid phase outlet, enters a lean-rich liquid heat exchanger for cooling, and the ethylene glycol lean liquid cooled by the lean-rich liquid heat exchanger enters a lean liquid air cooler for further cooling; The fuel gas is input into the ethylene glycol reboiler at the bottom of the ethylene glycol regeneration tower to form an azeotrope with the water in the ethylene glycol rich liquid, and is distilled out from the top of the ethylene glycol regeneration tower in the form of steam. The steam at the top of the ethylene glycol regeneration tower is heat-exchanged and cooled with the ethylene glycol rich liquid in the top heat exchanger. Part of the condensate formed by cooling is used as the top reflux and returns to the top of the ethylene glycol regeneration tower by gravity. The cooled steam is the regenerated tail gas, which enters the top air cooler for cooling. The cooled regenerated tail gas enters the steam-water separator. After gas-liquid separation, the separated liquid phase goes to the downstream sewage treatment system, and the separated gas phase is pressurized and recycled to the ethylene glycol reboiler at the bottom of the ethylene glycol regeneration tower for use. The excess gas generated during the ethylene glycol regeneration process is discharged to the downstream through the top exhaust pipeline and the exhaust control valve connected to the supercharger.

[0005] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions: In the above-mentioned ethylene glycol reboiler, the fuel gas (Nm 3 ) and the amount of water in the glycol rich solution (m 3 ) has a volume ratio of 1.5 to 3.0.

[0006] The fuel gas is one or more of methane, ethane, propane and butane.

[0007] The second technical solution of the present invention is achieved by the following measures: a device for implementing the ethylene glycol dehydration regeneration process using azeotropic distillation as described in one of the technical solutions, comprising an ethylene glycol regeneration tower, a tower top heat exchanger, a tower top air cooler, a steam-water separator, a supercharger, an ethylene glycol reboiler, a lean-rich liquid heat exchanger and a lean liquid air cooler, the tower top heat exchanger and the ethylene glycol regeneration tower are connected in sequence from top to bottom, the rich liquid inlet of the tower top heat exchanger is connected to an ethylene glycol rich liquid pipeline, the rich liquid outlet of the tower top heat exchanger is connected to the rich liquid inlet of the lean-rich liquid heat exchanger, the rich liquid outlet of the lean-rich liquid heat exchanger is connected to the top of the ethylene glycol regeneration tower, the bottom of the ethylene glycol regeneration tower is fixedly connected to the top of the ethylene glycol reboiler, and the ethylene glycol regeneration tower is connected to the top of the ethylene glycol reboiler. The bottom liquid phase outlet of the glycol reboiler is connected with the lean liquid inlet of the lean-rich liquid heat exchanger, the lean liquid outlet of the lean-rich liquid heat exchanger is connected with the lean liquid inlet of the lean liquid air cooler, the top gas phase outlet of the tower top heat exchanger is connected with the tower top air cooler inlet, the tower top air cooler outlet is connected with the steam-water separator feed port, the top gas phase outlet of the steam-water separator is connected with the supercharger air inlet, the supercharger air outlet is connected with the glycol reboiler through a gas phase pipeline, along the gas flow direction, the gas phase pipeline is sequentially connected with the tower top exhaust pipeline and the supplementary fuel gas pipeline, an exhaust control valve is fixedly installed on the tower top exhaust pipeline, and a flow control valve is fixedly installed on the gas phase pipeline between the supplementary fuel gas pipeline and the tower top exhaust pipeline.

[0008] The following is a further optimization and / or improvement of the second technical solution of the above invention: The tower top heat exchanger, ethylene glycol regeneration tower and ethylene glycol reboiler are integrated into one, the tower top heat exchanger is arranged at the top of the ethylene glycol regeneration tower, and the bottom of the ethylene glycol regeneration tower is connected with the top of the ethylene glycol reboiler.

[0009] The above-mentioned supercharger adopts a high-pressure Roots blower or compressor.

[0010] The above-mentioned ethylene glycol regeneration tower adopts a packed tower with 2 to 4 plates.

[0011] The lean liquid outlet of the lean liquid air cooler is connected to an ethylene glycol lean liquid delivery pipeline.

[0012] Compared with the existing conventional ethylene glycol rich liquid distillation regeneration process, under the condition of achieving the same ethylene glycol lean liquid regeneration concentration, the regeneration temperature of the present invention is reduced by at least 30°C, and low-frequency electromagnetic heater heating can be used, which is safer and more reliable than traditional resistance heater heating; the regeneration energy consumption is reduced by about 10%, and there is no regeneration tail gas emission, and the VOCs emission is 0, which has more environmental advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Attached Figure 1 The figure is a schematic diagram of the process flow of the ethylene glycol dehydration and regeneration process using azeotropic distillation according to the present invention.

[0014] The codes in the attached drawings are respectively: 1 is an ethylene glycol regeneration tower, 2 is a tower top heat exchanger, 3 is a tower top air cooler, 4 is a steam-water separator, 5 is a supercharger, 6 is an ethylene glycol reboiler, 7 is a lean and rich liquid heat exchanger, 8 is a lean liquid air cooler, 9 is an ethylene glycol rich liquid pipeline, 10 is a gas phase pipeline, 11 is a supplementary fuel gas pipeline, 12 is an ethylene glycol lean liquid delivery pipeline, 13 is a tower top exhaust pipeline, 14 is an exhaust control valve, and 15 is a flow control valve. DETAILED DESCRIPTION

[0015] The present invention is not limited by the following embodiments, and specific implementation methods can be determined based on the technical solution of the present invention and actual conditions.

[0016] In the present invention, for the convenience of description, the relative position relationship of each component is described according to the attached Figure 1 The layout is described in detail, such as the positional relationship of front, back, top, bottom, left, right, etc., which is based on the attached manual. Figure 1 The layout direction is determined by the

[0017] The present invention will be further described below in conjunction with embodiments: Embodiment 1: As attached Figure 1 As shown, the ethylene glycol dehydration and regeneration process using azeotropic distillation is carried out according to the following method: ethylene glycol rich liquid at a certain temperature and pressure is preheated by the ethylene glycol tower top heat exchanger 2, the preheated ethylene glycol rich liquid enters the lean-rich liquid heat exchanger 7 for further heating, the heated ethylene glycol rich liquid enters the ethylene glycol regeneration tower 1 from the top of the ethylene glycol regeneration tower 1, countercurrently contacts with the steam in the tower for stepwise heating and concentration, and then enters the ethylene glycol reboiler 6 at the bottom of the ethylene glycol regeneration tower 1, the ethylene glycol reboiler 6 heats the ethylene glycol rich liquid by a low-frequency electromagnetic heater to regenerate the ethylene glycol lean liquid, the regenerated ethylene glycol lean liquid flows out from the liquid phase outlet of the ethylene glycol reboiler 6, enters the lean-rich liquid heat exchanger 7 for cooling, the ethylene glycol lean liquid cooled by the lean-rich liquid heat exchanger 7 enters the lean liquid air cooler 8, and enters the ethylene glycol storage tank after further cooling; The fuel gas is input into the ethylene glycol reboiler 6 at the bottom of the ethylene glycol regeneration tower 1, forms an azeotrope with the water in the ethylene glycol rich liquid, and is distilled out from the top of the ethylene glycol regeneration tower 1 in the form of steam. The steam at the top of the ethylene glycol regeneration tower 1 is heat-exchanged and cooled with the ethylene glycol rich liquid in the top heat exchanger 2. Part of the condensate formed by cooling is used as the top reflux and returns to the top of the ethylene glycol regeneration tower 1 by gravity. The cooled steam is the regenerated tail gas, which enters the top air cooler 3 for cooling. The cooled regenerated tail gas enters the steam-water separator 4. After gas-liquid separation, the separated liquid phase goes to the downstream sewage treatment system, and the separated gas phase is pressurized and recycled to the ethylene glycol reboiler 6 at the bottom of the ethylene glycol regeneration tower 1 for use. The excess gas generated during the ethylene glycol regeneration process is discharged to the downstream through the top exhaust pipeline 13 and the exhaust control valve 14 connected to the supercharger 5.

[0018] Example 2: As an optimization of the above example, in the glycol reboiler 6, the fuel gas (Nm 3 ) and the amount of water in the glycol rich solution (m 3 ) has a volume ratio of 1.5 to 3.0.

[0019] The present invention utilizes the principle that organic hydrocarbon compounds and water can form a minimum azeotrope and uses fuel gas as an azeotropic agent, thereby reducing the boiling point of the azeotrope in the ethylene glycol reboiler 6 to reduce the energy consumption of ethylene glycol regeneration.

[0020] When the volume ratio of the fuel gas to the water content in the ethylene glycol rich liquid is controlled at 1.5 to 3.0, the azeotropic point of the fuel gas and the ethylene glycol rich liquid can be minimized.

[0021] Embodiment 3: As an optimization of the above embodiment, the fuel gas is one or more of methane, ethane, propane and butane. The selection of the fuel gas is conducive to the formation of an azeotrope with the lowest boiling point between the fuel gas and the ethylene glycol rich liquid.

[0022] Embodiment 4: As attached Figure 1 As shown, a device for implementing the ethylene glycol dehydration regeneration process using azeotropic distillation as described in the above embodiment comprises an ethylene glycol regeneration tower 1, a tower top heat exchanger 2, a tower top air cooler 3, a steam-water separator 4, a supercharger 5, an ethylene glycol reboiler 6, a lean-rich liquid heat exchanger 7 and a lean liquid air cooler 8. The tower top heat exchanger 2 and the ethylene glycol regeneration tower 1 are connected in sequence from top to bottom, the rich liquid inlet of the tower top heat exchanger 2 is connected to an ethylene glycol rich liquid pipeline 9, the rich liquid outlet of the tower top heat exchanger 2 is connected to the rich liquid inlet of the lean-rich liquid heat exchanger 7, the rich liquid outlet of the lean-rich liquid heat exchanger 7 is connected to the top of the ethylene glycol regeneration tower 1, the bottom of the ethylene glycol regeneration tower 1 is fixedly connected to the top of the ethylene glycol reboiler 6, and the liquid phase outlet of the bottom of the ethylene glycol reboiler 6 is connected to the lean-rich liquid exchanger. The lean liquid inlet of the tower top heat exchanger 7 is connected, the lean liquid outlet of the lean-rich liquid heat exchanger 7 is connected with the lean liquid inlet of the lean liquid air cooler 8, the top gas phase outlet of the tower top heat exchanger 2 is connected with the inlet of the tower top air cooler 3, the outlet of the tower top air cooler 3 is connected with the feed inlet of the steam-water separator 4, the top gas phase outlet of the steam-water separator 4 is connected with the air inlet of the supercharger 5, the air outlet of the supercharger 5 is connected with the ethylene glycol reboiler 6 through the gas phase pipeline 10, along the gas flow direction, the gas phase pipeline 10 is sequentially connected with the tower top exhaust pipeline 13 and the supplementary fuel gas pipeline 11, an exhaust control valve 14 is fixedly installed on the tower top exhaust pipeline 13, and a flow control valve 15 is fixedly installed on the gas phase pipeline 10 between the supplementary fuel gas pipeline 11 and the tower top exhaust pipeline 13.

[0023] The following are further optimizations and / or improvements to the above device: As required, the top heat exchanger 2, the ethylene glycol regeneration tower 1 and the ethylene glycol reboiler 6 are integrated into one, the top heat exchanger 2 is arranged at the top of the ethylene glycol regeneration tower 1, and the bottom of the ethylene glycol regeneration tower 1 is connected to the top of the ethylene glycol reboiler 6.

[0024] As required, the supercharger 5 adopts a high-pressure Roots blower or a compressor.

[0025] According to needs, the ethylene glycol regeneration tower 1 adopts a packed tower with 2 to 4 plates.

[0026] As attached Figure 1 As shown, the lean liquid outlet of the lean liquid air cooler 8 is connected to an ethylene glycol lean liquid delivery pipeline 12 .

[0027] The ethylene glycol lean liquid is delivered to the ethylene glycol storage tank via the ethylene glycol lean liquid delivery pipeline 12 .

[0028] Embodiment 5: As attached Figure 1 As shown, the ethylene glycol dehydration regeneration process using azeotropic distillation is carried out as follows: the ethylene glycol rich liquid with a temperature of 30°C to 45°C and a pressure of 0.2MPa is preheated to 55°C to 60°C by the top heat exchanger 2 of the ethylene glycol regeneration tower 1, the preheated ethylene glycol rich liquid enters the lean-rich liquid heat exchanger 7 and is further heated to 70°C to 80°C, the heated ethylene glycol rich liquid enters the ethylene glycol regeneration tower 1 from the top of the ethylene glycol regeneration tower 1, and is countercurrently contacted with the steam in the tower. After step-by-step heating and concentration, the ethylene glycol enters the ethylene glycol reboiler 6 at the bottom of the ethylene glycol regeneration tower 1. The ethylene glycol reboiler 6 heats the ethylene glycol rich liquid to 85°C to 95°C through a low-frequency electromagnetic heater. The regenerated ethylene glycol lean liquid flows out from the liquid phase outlet of the ethylene glycol reboiler 6 and enters the lean-rich liquid heat exchanger 7 to be cooled to 65°C to 70°C. The ethylene glycol lean liquid cooled by the lean-rich liquid heat exchanger 7 enters the lean liquid air cooler 8, and enters the ethylene glycol storage tank after being further cooled to 45°C to 50°C. The fuel gas is decompressed to 0.2MPa and the fuel gas (Nm 3 ): Water content in ethylene glycol rich solution (m 3 )=1.5 to 3.0 (volume ratio) is added into the ethylene glycol reboiler 6, forms an azeotrope with the water in the ethylene glycol rich liquid, and is distilled out from the top of the ethylene glycol regeneration tower 1 in the form of steam. The steam from the top of the ethylene glycol regeneration tower 1 exchanges heat with the ethylene glycol rich liquid in the top heat exchanger 2 and is cooled to 70°C to 80°C. Part of the condensate is used as the top reflux and returns to the top of the ethylene glycol regeneration tower 1 by gravity. The cooled steam is the regeneration tail gas, which enters the top air cooler 3 and is cooled to 45°C to 50°C. The cooled regeneration tail gas enters the steam-water separator 4. After gas-liquid separation, the separated liquid phase goes to the downstream sewage treatment system, and the separated gas phase goes to the high-pressure Roots blower for pressurization. The regeneration tail gas pressurized by the high-pressure Roots blower to 0.2MPa is recycled to the ethylene glycol reboiler 6.

[0029] Embodiment 6: As attached Figure 1As shown, the ethylene glycol dehydration regeneration process using azeotropic distillation is carried out as follows: the ethylene glycol rich liquid with a temperature of 45°C and a pressure of 0.2MPa is preheated to 60°C through the tower top heat exchanger 2 of the ethylene glycol regeneration tower 1, and the preheated ethylene glycol rich liquid enters the lean-rich liquid heat exchanger 7 for further heating to 80°C, and the heated ethylene glycol rich liquid enters the ethylene glycol regeneration tower 1 from the top of the ethylene glycol regeneration tower 1, and is countercurrently contacted with the steam in the tower for heating and concentration step by step, and then enters the ethylene glycol reboiler 6 at the bottom of the ethylene glycol regeneration tower 1, and the ethylene glycol reboiler 6 heats the ethylene glycol rich liquid to 95°C through a low-frequency electromagnetic heater, and the regenerated ethylene glycol lean liquid flows out from the liquid phase outlet of the ethylene glycol reboiler 6, enters the lean-rich liquid heat exchanger 7 and is cooled to 70°C, and the ethylene glycol lean liquid cooled by the lean-rich liquid heat exchanger 7 enters the lean liquid air cooler 8, and is further cooled to 50°C before entering the ethylene glycol storage tank; Methane is decompressed to 0.2 MPa and then 3 ): Water content in ethylene glycol rich solution (m 3 )=2.0 (volume ratio) is added into the ethylene glycol reboiler 6, forms an azeotrope with the water in the ethylene glycol rich liquid, and is distilled out from the top of the ethylene glycol regeneration tower 1 in the form of steam. The steam from the top of the ethylene glycol regeneration tower 1 exchanges heat with the ethylene glycol rich liquid in the top heat exchanger 2 and is cooled to 80°C. Part of the condensate is used as the top reflux and returns to the top of the ethylene glycol regeneration tower 1 by gravity. The cooled steam is the regenerated tail gas, which enters the top air cooler 3 and is cooled to 50°C. The cooled regenerated tail gas enters the steam-water separator 4. After gas-liquid separation, the separated liquid phase goes to the downstream sewage treatment system, and the separated gas phase goes to the high-pressure Roots blower for pressurization. The regenerated tail gas pressurized by the high-pressure Roots blower at 0.2MPa is recycled to the ethylene glycol reboiler 6.

[0030] Embodiment 7: As attached Figure 1 As shown, the ethylene glycol dehydration regeneration process using azeotropic distillation is carried out as follows: the ethylene glycol rich liquid with a temperature of 30°C and a pressure of 0.2MPa is preheated to 55°C by the tower top heat exchanger 2 of the ethylene glycol regeneration tower 1, the preheated ethylene glycol rich liquid enters the lean-rich liquid heat exchanger 7 and is further heated to 70°C, the heated ethylene glycol rich liquid enters the ethylene glycol regeneration tower 1 from the top of the ethylene glycol regeneration tower 1, countercurrently contacts with the steam in the tower and is heated and concentrated step by step, and then enters the ethylene glycol reboiler 6 at the bottom of the ethylene glycol regeneration tower 1, the ethylene glycol reboiler 6 heats the ethylene glycol rich liquid to 85°C by a low-frequency electromagnetic heater, the regenerated ethylene glycol lean liquid flows out from the liquid phase outlet of the ethylene glycol reboiler 6, enters the lean-rich liquid heat exchanger 7 and is cooled to 65°C, the ethylene glycol lean liquid cooled by the lean-rich liquid heat exchanger 7 enters the lean liquid air cooler 8, is further cooled to 45°C and then enters the ethylene glycol storage tank; Ethane was decompressed to 0.2 MPa and the ethane (Nm 3 ): Water content in ethylene glycol rich solution (m 3)=1.5 (volume ratio) is added into the ethylene glycol reboiler 6, forms an azeotrope with the water in the ethylene glycol rich liquid, and is distilled out from the top of the ethylene glycol regeneration tower 1 in the form of steam. The steam from the top of the ethylene glycol regeneration tower 1 exchanges heat with the ethylene glycol rich liquid in the top heat exchanger 2 and is cooled to 70°C. Part of the condensate is used as the top reflux and returns to the top of the ethylene glycol regeneration tower 1 by gravity. The cooled steam is the regenerated tail gas, which enters the top air cooler 3 and is cooled to 45°C. The cooled regenerated tail gas enters the steam-water separator 4. After gas-liquid separation, the separated liquid phase goes to the downstream sewage treatment system, and the separated gas phase goes to the high-pressure Roots blower for pressurization. The regenerated tail gas pressurized by the high-pressure Roots blower to 0.2MPa is recycled to the ethylene glycol reboiler 6.

[0031] Compared with the prior art, the present invention has the following positive effects: 1) Compared with the existing conventional ethylene glycol rich liquid distillation regeneration process, under the condition of achieving the same ethylene glycol lean liquid regeneration concentration, the regeneration temperature is reduced by at least 30°C (see Examples 6 and 7 for details), and low-frequency electromagnetic heater heating can be achieved, which is safer and more reliable than traditional resistance heater heating; 2) Compared with the existing conventional ethylene glycol rich liquid distillation regeneration process, under the condition of achieving the same ethylene glycol lean liquid regeneration concentration, the regeneration energy consumption is reduced by about 10%; 3) Compared with the existing conventional ethylene glycol rich liquid distillation regeneration process, this process technology has no regeneration tail gas emissions and VOCs emissions of 0, which is more environmentally friendly.

[0032] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

Claims

1. A process for dehydrating and regenerating ethylene glycol by azeotropic distillation, characterized in that The method is as follows: ethylene glycol rich liquid at a certain temperature and pressure is preheated by a glycol tower top heat exchanger, the preheated ethylene glycol rich liquid enters a lean-rich liquid heat exchanger for further heating, the heated ethylene glycol rich liquid enters an ethylene glycol regeneration tower from the top of an ethylene glycol regeneration tower, is countercurrently contacted with steam in the tower for stepwise heating and concentration, and then enters an ethylene glycol reboiler at the bottom of the ethylene glycol regeneration tower, the ethylene glycol reboiler heats the ethylene glycol rich liquid by a low-frequency electromagnetic heater to regenerate the ethylene glycol lean liquid, the regenerated ethylene glycol lean liquid flows out from the ethylene glycol reboiler liquid phase outlet, enters a lean-rich liquid heat exchanger for cooling, and the ethylene glycol lean liquid cooled by the lean-rich liquid heat exchanger enters a lean liquid air cooler for further cooling; The fuel gas is input into the ethylene glycol reboiler at the bottom of the ethylene glycol regeneration tower to form an azeotrope with the water in the ethylene glycol rich liquid, and is distilled out from the top of the ethylene glycol regeneration tower in the form of steam. The steam at the top of the ethylene glycol regeneration tower is heat-exchanged and cooled with the ethylene glycol rich liquid in the top heat exchanger. Part of the condensate formed by cooling is used as the top reflux and returns to the top of the ethylene glycol regeneration tower by gravity. The cooled steam is the regenerated tail gas, which enters the top air cooler for cooling. The cooled regenerated tail gas enters the steam-water separator. After gas-liquid separation, the separated liquid phase goes to the downstream sewage treatment system, and the separated gas phase is pressurized and recycled to the ethylene glycol reboiler at the bottom of the ethylene glycol regeneration tower for use. The excess gas generated during the ethylene glycol regeneration process is discharged to the downstream through the top exhaust pipeline and the exhaust control valve connected to the supercharger.

2. The ethylene glycol dehydration and regeneration process using azeotropic distillation according to claim 1, characterized in that In the glycol reboiler, the volume ratio of the fuel gas to the water in the glycol rich liquid is 1.5 to 3.

0.

3. The ethylene glycol dehydration and regeneration process using azeotropic distillation according to claim 1 or 2, characterized in that The fuel gas is one or more of methane, ethane, propane and butane.

4. A device for implementing the ethylene glycol dehydration and regeneration process using azeotropic distillation according to claim 1, 2 or 3, characterized in that The invention comprises an ethylene glycol regeneration tower, a tower top heat exchanger, a tower top air cooler, a steam-water separator, a supercharger, an ethylene glycol reboiler, a lean-rich liquid heat exchanger and a lean liquid air cooler. The tower top heat exchanger and the ethylene glycol regeneration tower are connected in sequence from top to bottom. The rich liquid inlet of the tower top heat exchanger is connected with an ethylene glycol rich liquid pipeline. The rich liquid outlet of the tower top heat exchanger is connected with the rich liquid inlet of the lean-rich liquid heat exchanger. The rich liquid outlet of the lean-rich liquid heat exchanger is connected with the top of the ethylene glycol regeneration tower. The bottom of the ethylene glycol regeneration tower is fixedly connected with the top of the ethylene glycol reboiler. The liquid phase outlet of the bottom of the ethylene glycol reboiler is connected with the lean liquid inlet of the lean-rich liquid heat exchanger. The lean liquid outlet of the rich liquid heat exchanger is connected with the lean liquid inlet of the lean liquid air cooler, the top gas phase outlet of the tower top heat exchanger is connected with the tower top air cooler inlet, the tower top air cooler outlet is connected with the steam-water separator feed port, the top gas phase outlet of the steam-water separator is connected with the supercharger air inlet, the supercharger air outlet is connected with the ethylene glycol reboiler through a gas phase pipeline, along the gas flow direction, the gas phase pipeline is sequentially connected with the tower top exhaust pipeline and the supplementary fuel gas pipeline, an exhaust control valve is fixedly installed on the tower top exhaust pipeline, and a flow control valve is fixedly installed on the gas phase pipeline between the supplementary fuel gas pipeline and the tower top exhaust pipeline.

5. The device according to claim 4, characterized in that The tower top heat exchanger, the ethylene glycol regeneration tower and the ethylene glycol reboiler are integrated into one, the tower top heat exchanger is arranged at the top of the ethylene glycol regeneration tower, and the bottom of the ethylene glycol regeneration tower is connected with the top of the ethylene glycol reboiler.

6. The device according to claim 4 or 5, characterized in that The supercharger adopts a high-pressure Roots blower or compressor.

7. The device according to claim 4 or 5, characterized in that The lean liquid outlet of the lean liquid air cooler is connected with an ethylene glycol lean liquid delivery pipeline.

8. The device according to claim 6, characterized in that The lean liquid outlet of the lean liquid air cooler is connected with an ethylene glycol lean liquid delivery pipeline.

9. The device according to claim 4, 5 or 8, characterized in that The ethylene glycol regeneration tower adopts a packed tower with 2 to 4 plates.

10. The device according to claim 7, characterized in that The ethylene glycol regeneration tower adopts a packed tower with 2 to 4 plates.

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