High vacuum condensing gas-liquid separation device

Abstract

The application relates to the technical field of gas-liquid separation, and discloses a high-vacuum condensing gas-liquid separation device which comprises a front separation tank, a tubular heat exchanger is arranged in the front separation tank in a sealed mode; gas enters the tubular heat exchanger from the front separation tank and is discharged from bottom to top through negative pressure suction; cooling water flows into the front separation tank from the side and exchanges heat with the tubular heat exchanger and is discharged from the other side, and condensed water formed through heat exchange is discharged from the condensed water discharge port at the bottom of the front separation tank. Through the integrated design of the tubular heat exchanger and the front separation tank, the cooling water and the gas are fully heat-exchanged in the tubular heat exchanger, the mixed gas and the cooling water are fully contacted, and the purpose of heat transfer is achieved. The overall structure is simple and has high integration degree, the cooling effect is good, steam and water can be effectively separated, the overall land occupation is small, on-site installation is convenient, and the device is suitable for popularization and application.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gas-liquid separation, in particular to a high-vacuum condensing gas-liquid separation device. BACKGROUND

[0002] In the vacuum pumping device of the air-cooled unit of power station (including direct air-cooled and indirect air-cooled), the sucked gas is usually high in temperature and contains a large amount of water vapor. If the temperature of this part of gas is not reduced, it will directly transfer heat to the sealing water of the vacuum pump, causing the temperature of the sealing water to rise. Meanwhile, a large amount of water vapor will also increase the power consumption of the vacuum pump.

[0003] The water ring vacuum pump is a volumetric vacuum pump, which is composed of a suction chamber and a discharge chamber. The volume of the suction chamber and the discharge chamber determines the size of the suction air volume of the vacuum pump.

[0004] The sealing water of the vacuum pump mainly plays a role in sealing and transferring energy.

[0005] Water or liquid will form a certain saturated vapor pressure at a certain temperature, which will form a certain air pocket in the suction chamber of the vacuum pump, occupying the suction space of the vacuum pump. With the increase of the temperature of the water or liquid, the vaporization pressure will increase, the volume of the formed air pocket will increase, and the effective suction space of the vacuum pump will decrease, and the output of the vacuum pump will obviously decrease.

[0006] The mixed gas discharged from the condenser of the power station contains a large amount of water vapor. According to the American HEI standard, when the design pressure of the condenser is 3.4 KPa and the inlet gas temperature is 21℃, the weight ratio of the non-condensable gas to the water vapor is 1:2.2.

[0007] The proportion of the non-condensable gas to the water vapor in the mixed gas discharged from the condenser is affected by the temperature of the discharged gas and the design pressure of the condenser. Under different working conditions, the respective contents can be calculated by formula.

[0008] In the direct air-cooled unit, the content ratio of dry air to water vapor is generally 1:3.5; in the indirect air-cooled unit, the content ratio of dry air to water vapor is 1:3.0. If these water vapors do not condense, the air pumping capacity of the vacuum pump will inevitably increase, and the power consumption of the vacuum pump will also increase.

[0009] In the direct air-cooled unit, the temperature of the mixed gas discharged from the condenser is generally about 75℃, and the temperature of the mixed gas discharged from the indirect air-cooled unit is about 70℃. The normal sealing water temperature of the vacuum pump is about 20 / 35℃. According to the principle of energy conservation, the mixing of high-temperature gas and low-temperature liquid will cause the temperature of the sealing water to rise. Generally speaking, the temperature difference between the inlet gas temperature and the cooling water temperature will increase by about 3℃ for every 10℃ increase in the temperature difference (the temperature rise caused by different vacuum degrees is not consistent, and it is difficult to have an accurate data).

[0010] In chemical industry, tail gas recovery, catalytic fission process, the exhaust gas often accompanied by high temperature and a large amount of water vapor, and water vapor is not allowed to bring into the next process, if a large amount of water vapor into the next process, will reduce the chemical reaction rate, at the same time reduce the quality of the product.

[0011] If this part of the high temperature gas is not cooled, according to the law of conservation of energy, the mixed gas directly transfers heat to the sealing water of the vacuum pump, thereby causing the sharp rise of the sealing water temperature of the vacuum pump, and the pumping capacity of the vacuum pump will be significantly reduced, accompanied by cavitation and noise, which directly affects the service life of the vacuum pump and environmental protection.

[0012] At present, the common process at home and abroad is to install a heat exchanger (plate or tube) before the vacuum pump. Because the cooling water flows in the tube bundle (or outside the shell), the gas flow rate is very fast, generally reaching 20-25 m / s, and the tube bundle cannot be designed infinitely long. The cooling water flows inside the tube bundle, and only one side of the inner wall of the tube bundle exchanges heat, and only a small part of the cooling water in the middle of the tube bundle participates in heat exchange, so the cooling effect is not very good. At the same time, the residual liquid produced by the condensation of water vapor will accumulate at the lower part of the shell, directly affecting the cooling effect of the heat exchanger.

[0013] Based on the above reasons, it is urgent to develop a set bundle type device which has good cooling effect, can effectively separate steam and water, has small overall land occupation and is convenient for on-site installation. SUMMARY

[0014] The application provides a high vacuum condensation gas-liquid separation device, which solves the above technical problems.

[0015] The application provides a high vacuum condensation gas-liquid separation device, which includes a front separation tank, and a tubular heat exchanger is sealingly arranged in the front separation tank.

[0016] The gas enters the tubular heat exchanger from the front separation tank and is discharged from bottom to top by negative pressure suction.

[0017] The cooling water flows into the front separation tank from the side and exchanges heat with the tubular heat exchanger, and then is discharged from the other side. The condensed water formed by heat exchange is discharged from the condensed water discharge port at the bottom of the front separation tank.

[0018] Preferably, the tubular heat exchanger includes two heat exchanger tube plates and a plurality of heat exchanger tube bundles. The heat exchanger tube plates are sealingly welded with the inner wall of the front separation tank. The two ends of each heat exchanger tube bundle are connected with the heat exchanger tube plates. The gas enters the heat exchanger tube bundle and is discharged from bottom to top. Each heat exchanger tube bundle is immersed in the cooling water.

[0019] Preferably, a plurality of water injection holes are arranged in the same plane of the heat exchanger tube bundle, and the cooling water is injected into the heat exchanger tube bundle through the water injection holes to form a water curtain, and the gas and the water curtain are fully heat exchanged.

[0020] Preferably, a plurality of water injection holes are arranged in the same plane of the heat exchanger tube bundle, and the cooling water is injected into the heat exchanger tube bundle through the water injection holes to form a water curtain, and the gas and the water curtain are fully heat exchanged.

[0021] Preferably, the distance between the adjacent two layers of water injection holes is about 200 mm.

[0022] Preferably, 3-4 water injection holes are arranged in the same plane of the heat exchanger tube bundle.

[0023] Preferably, the front separation tank is provided with a gas outlet at the top, a gas inlet at the lower side, a condensate water discharge outlet at the bottom, a cooling water inlet at the upper side, and a cooling water outlet at the lower side of the other side.

[0024] Preferably, the high-vacuum condensation gas-liquid separation device further comprises a negative pressure pump, and the negative pressure pump is communicated with the upper end gas outlet of the front separation tank through a balance pipe, and the balance pipe is also communicated with the condensate water discharge outlet.

[0025] Beneficial effects: the present application provides a high-vacuum condensation gas-liquid separation device, which comprises a front separation tank, and a tubular heat exchanger is sealingly arranged in the front separation tank; the gas enters the tubular heat exchanger from the front separation tank and is discharged from bottom to top by negative pressure suction; the cooling water flows into the front separation tank from the side and is heat exchanged with the tubular heat exchanger and then discharged from the other side, and the condensate water formed by the heat exchange is discharged from the condensate water discharge outlet at the bottom of the front separation tank. Through the integrated design of the tubular heat exchanger and the front separation tank, the cooling water and the gas are fully heat exchanged in the tubular heat exchanger, so that the mixed gas and the cooling water are fully contacted, and the purpose of heat transfer is achieved. The overall structure design is simple and has high integration degree, good cooling effect, effective steam and water separation, small overall land occupation, convenient on-site installation, and is suitable for popularization and application.

[0026] The above description is only a summary of the technical scheme of the present application, in order to more clearly understand the technical means of the present application, and the content of the specification can be implemented. The following is a detailed description of the preferred embodiments of the present application with reference to the accompanying drawings. The specific embodiments of the present application are described in detail by the following examples and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present application, and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 The high vacuum condensation gas-liquid separation device structure principle diagram provided by the present application;

[0029] Figure 2 The overall structure diagram of the tube heat exchanger provided by the present application;

[0030] Figure 3 The plane cross-sectional view of the tube heat exchanger provided by the present application.

[0031] Explanation of reference signs:

[0032] 1 is a gas outlet, 2 is a front separation tank, 3 is a heat exchanger tube plate, 4 is a cooling water inlet, 5 is a tube heat exchanger, 6 is a gas inlet, 7 is a cooling water outlet, 8 is a balance pipe, 9 is a balance pipe regulating valve, 10 is a drain pipe, 11 is an inlet regulating valve, 12 is a negative pressure pump, 13 is a motor, 14 is a negative pressure pump discharge pipeline, and 15 is a discharge pipeline connecting flange.

[0033] 31 is a heat exchanger tube bundle, 32 is a water spraying hole, and 33 is a water curtain. DETAILED DESCRIPTION

[0034] The principles and features of the present application are described below in conjunction with the accompanying drawings, and the examples are used only to explain the present application and are not intended to limit the scope of the present application. In the following paragraphs, the present application is described in more detail by way of example with reference to the accompanying drawings. The advantages and features of the present application will be more apparent from the following description and claims. It should be noted that the drawings are very simplified and all use non-precise proportions, only to facilitate, clearly assist the purpose of explaining the embodiments of the present application.

[0035] It should be noted that when a component is referred to as being "fixed" to another component, it can be directly on the other component or there can be a middle component. When a component is referred to as being "connected" to another component, it can be directly connected to the other component or there can be a middle component. When a component is referred to as being "disposed" on another component, it can be directly disposed on the other component or there can be a middle component. The terms "vertical", "horizontal", "left", "right", and the like used herein are for illustrative purposes only.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein is only for the purpose of describing specific embodiments and is not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0037] AsFigure 1 As shown, the application provides a high-vacuum condensing gas-liquid separation device. Due to space and site limitations, the device requires a small floor area and adopts a containerized structure. The device mainly comprises a front separation tank 2 and a tubular heat exchanger 5. Through integrated design, the degree of equipment integration is further improved, and the area of the original tubular heat exchanger is reduced by more than 50%.

[0038] The tubular heat exchanger 5 is arranged in the front separation tank 2, and three or four water spray holes 32 are arranged on the heat exchanger tube bundle 31. The size of the holes is determined according to the amount of cooling water, the size of water pressure, and the level of vacuum degree. Generally, the water spray holes 32 are arranged on the same plane. Generally, the tube bundle is provided with 3-5 layers of such water spray holes 32, and the water spray holes 32 of each tube are staggered.

[0039] The tubular heat exchanger 5 is arranged in the front separation tank 2, and three or four water spray holes 32 are arranged on the heat exchanger tube bundle 31. The size of the holes is determined according to the amount of cooling water, the size of water pressure, and the level of vacuum degree. Generally, the water spray holes 32 are arranged on the same plane. Generally, the tube bundle is provided with 3-5 layers of such water spray holes 32, and the water spray holes 32 of each tube are staggered.

[0039] The tubular heat exchanger 5 is arranged in the front separation tank 2, and three or four water spray holes 32 are arranged on the heat exchanger tube bundle 31. The size of the holes is determined according to the amount of cooling water, the size of water pressure, and the level of vacuum degree. Generally, the water spray holes 32 are arranged on the same plane. Generally, the tube bundle is provided with 3-5 layers of such water spray holes 32, and the water spray holes 32 of each tube are staggered.

[0040] The specific working principle is as follows:

[0041] When the high-pressure cooling water enters the pre-separation tank 2 through the cooling water inlet 4, the cooling water enters the heat exchange space, exchanges heat through the tubular heat exchanger 5, and finally flows out from the cooling water outlet 7. The cooling water has a certain pressure. The cooling water inlet is arranged at the upper part of one side of the pre-separation tank 2, and the cooling water outlet 7 is arranged at the lower part of the other side of the pre-separation tank 2, so that the cooling water can fill the entire heat exchange space in the pre-separation tank 2 as much as possible, thereby maximizing the contact surface of the cooling water and the tubular heat exchanger 5. When the cooling water passes through the outer wall of the tube of the tubular heat exchanger 5 in the pre-separation tank 2, the cooling water will enter the heat exchanger tube bundle 31 through the water injection holes 32 under the action of pressure. Each opening forms a 120-degree sector water column, and three openings form a 360-degree sector water column, thereby forming a water curtain 33. Since the opening is small, the cooling water forms a mist. When the high-temperature gas flows in the heat exchanger tube bundle 31, the high-temperature gas will be in full contact with the water curtain 33, so that the gas temperature can be quickly reduced, and the water vapor can be quickly condensed into water. Since multiple heat exchanger tube bundles 31 are adopted, each heat exchanger tube bundle 31 has a multi-layer structure, and each layer has a water curtain 33. The mixed gas is cooled multiple times and sufficiently, so that the inlet gas temperature can be effectively reduced.

[0042] In addition, a negative pressure pump 12 is installed at the bottom of the pre-separation tank 2. The suction range of the negative pressure pump 12 is only 6-6.5 meters, while the vacuum of the unit system is 9-9.5 meters. Therefore, under normal circumstances, the negative pressure pump 12 cannot suck the cooling water. The present application installs a balance pipe 8 between the pre-separation tank 2 and the negative pressure pump 12, so that the inlet pressure of the negative pressure pump 12 is balanced with the pre-separation tank 2. Therefore, the negative pressure pump 12 can rely on its own suction range to suck the cooling water from the bottom of the pre-separation tank 2, that is, the cooling water flows out from the drain pipe 10 at the bottom of the pre-separation tank 2. The inlet regulating valve 11 is arranged on the drain pipe 10, which is used for flow control of the cooling water extraction. The balance pipe 8 plays a pressure balancing role. The negative pressure pump 12 is driven by the motor 13, and the extracted cooling water finally flows out through the negative pressure pump discharge pipe 14. The discharge pipe connecting flange 15 is arranged at the negative pressure pump discharge pipe 14, which is convenient for connecting the discharge pipe to better discharge the cooling water, or directly recycled and connected to the cooling water inlet 4 to realize self-circulation.

[0043] Since the cooling water inlet and outlet and the inlet of the negative pressure pump 12 of the device are provided with manual regulating valves, and the balance pipe regulating valve 9 is arranged on the balance pipe 8, when it is not needed to be put into use, the valve can be quickly closed, so that the device becomes an intake pipe section without affecting the operation of the original equipment.

[0044] The mixed gas flows upward along the inside of the heat exchanger tube bundle 31, while the cooling water is sucked from the bottom of the pre-separation tank 2 in the opposite direction of the gas, so that the mixed gas is fully exchanged with the cooling water. Since multiple water injection holes 32 are arranged on the heat exchanger tube bundle 31, multiple heat exchanges are performed, so as to rapidly reduce the inlet gas temperature and make the water vapor rapidly condense.

[0045] In a specific implementation scenario:

[0046] Referring to Figure 1 the drawing, a high-vacuum condensing gas-liquid separation device mainly comprises a pre-separation tank 2, a tubular heat exchanger 5, a negative pressure pump 12, a negative pressure pump matching motor 13, and the like.

[0047] When high-temperature mixed gas (composed of water vapor, non-condensable gas, and the like) enters the pre-separation tank from the gas inlet 6;

[0048] The tubular heat exchanger 5 is composed of upper and lower heat exchanger tube plates 3, multiple heat exchanger tube bundles 31, and a shell. The shell of the heat exchanger is borrowed from the shell of the pre-separation tank 2, that is, the upper and lower heat exchanger tube plates 3 are welded with the inner wall of the pre-separation tank 2, so that the tubular heat exchanger 5 is hidden in the pre-separation tank 2 and achieves a sealing effect.

[0049] The cooling water of the tubular heat exchanger 5 enters the inside of the heat exchanger tube bundle 31 through the water injection holes 32 arranged on the heat exchanger tube bundle 31. Since 3-4 water injection holes are arranged on the same plane of the heat exchanger tube bundle 31, they form a water curtain 33. Since multiple water injection holes are arranged on the heat exchanger tube bundle 31, multiple water curtains 33 are formed. Under the action of the vacuumizing device, the mixed gas flows at a high speed along the heat exchanger tube bundle 31 of the tubular heat exchanger 5, and the high-temperature gas is exchanged through the multiple water curtains 33. Thus, the cooling water is fully contacted with the mixed gas, and heat exchange is fully performed between them.

[0050] The water in the pre-separation tank 2 is drained through the drain pipe 10 installed at the bottom of the pre-separation tank 2 and enters the negative pressure pump 12. Since the suction stroke of the general negative pressure pump 12 is only 6-6.5 meters of water column, and the negative pressure of the vacuumizing device is 9-9.5 meters of water column, at this time, the negative pressure pump 12 cannot suck water, but the negative pressure of the vacuumizing device sucks the water in the negative pressure pump 12 into the vacuumizing device.

[0051] At this time, a balance pipe 8 is installed at the suction inlet of the negative pressure pump 12 and the upper part of the pre-separation tank 2, so that the inlet pressure of the negative pressure pump 12 is balanced with the inlet of the vacuumizing device. The negative pressure pump 12 can rely on its own suction stroke to suck out the cooling water and the water rapidly condensed from the mixed gas;

[0052] Because the multi-layer water curtain 33 is arranged on the heat exchanger tube bundle 31, the cooling water can be in contact with the high-temperature gas in the whole heat exchanger tube bundle 31, and the cooling water can enter the suction chamber of the negative pressure pump 12 by the gravity and suction stroke of the negative pressure pump 12, and the cooling water and the condensed water of the water vapor are extracted from the bottom of the pre-separation tank 2 by the negative pressure pump 12.

[0053] The negative pressure pump 12 is selected for the high-vacuum condensing gas device because the impeller of the negative pressure pump 12 is always immersed in the liquid, the inlet and outlet are separated by a partition plate, and the negative pressure pump can be idled under the action of centrifugal force, and only the liquid can be discharged, and the vacuum cannot be formed in the suction chamber.

[0054] Referring to Figure 2 The tubular heat exchanger 5 is composed of the heat exchanger tube bundle 31 and the water injection hole 32, when the cooling water enters the outer wall of the heat exchanger tube bundle 31, the cooling water can enter the inside of the heat exchanger tube bundle 31 through the water injection hole 32 under the action of the pressure of the cooling water. At this time, under the action of the suction pressure of the vacuum extraction device, the mixed gas, i.e. the high-temperature gas, can be sucked into the vacuum extraction device along the heat exchanger tube bundle 31 together with the cooling water, so that the mixed gas can be fully mixed with the cooling water, so that the mixed gas can transfer heat to the cooling water, and the water vapor in the mixed gas can be quickly condensed into water, so that the purpose of reducing the inlet gas temperature and promoting the quick condensation of the water vapor is achieved.

[0055] Referring to Figure 3 When the cooling water enters the inside of the heat exchanger tube bundle 31 through the water injection hole 2, a pressure difference can be generated between the pressure of the cooling water and the negative pressure of the suction of the vacuum extraction device, and the cooling water can form a 120-degree conical small water column under the action of the pressure difference. Because three water injection holes 32 are drilled on the heat exchanger tube bundle 31, the three water injection holes 32 can form a 360-degree water curtain 33 without dead angle, and when the mixed gas passes through the heat exchanger tube bundle 31, the mixed gas can only pass through the water curtain 33, so that the mixed gas can be fully contacted with the cooling water, and the purpose of heat transfer is achieved.

[0056] Beneficial effects: the high-vacuum condensing gas-liquid separation device is disclosed, the high-vacuum mixed gas enters through the gas inlet 6, passes through the pre-separation tank 2 and the tubular heat exchanger 5, and enters the vacuum extraction device through the connecting port 1.

[0057] In this suction process, the cooling water can be fully contacted with the mixed gas through the water injection hole arranged on the heat exchanger tube bundle 3 to transfer heat, so that the temperature of the mixed gas is reduced, and the water vapor in the mixed gas is quickly condensed into water, so that the purpose of reducing the inlet gas temperature and improving the vacuum extraction device is achieved.

[0058] The balance pipe is arranged between the pre-separation tank 2 and the negative pressure pump 12, which plays a role of pressure balance, and the regulating valve in the balance pipe plays a role of regulating the gas flow.

[0059] The cooling water in the pre-separation tank and the quick condensate water in the mixed gas are extracted by the negative pressure pump 12, so as to reduce the intake temperature and improve the output of the vacuum pump device.

[0060] In order to facilitate the on-site installation and the modification of the old equipment, all the equipment is installed together, so as to reduce the occupied area and facilitate the installation.

[0061] The above is only the preferred embodiment of the present application, and does not limit the present application in any form; any ordinary technical personnel in the industry can implement the present application according to the drawings and the above description; however, any equivalent changes, modifications and evolution of the above disclosed technical content without departing from the technical solution of the present application are equivalent embodiments of the present application; at the same time, any equivalent changes, modifications and evolution of the above embodiments according to the essential technology of the present application are still within the protection scope of the technical solution of the present application.

Claims

1. A high vacuum condensing gas-liquid separation device, characterized by, The front separation tank is internally sealed with a tubular heat exchanger; The gas enters the tubular heat exchanger from the front separation tank, and is discharged from bottom to top by negative pressure suction; The high-pressure cooling water flows into the front separation tank from the side, exchanges heat with the tubular heat exchanger, and is discharged from the other side, and the condensed water formed by heat exchange is discharged from the condensed water outlet at the bottom of the front separation tank; The tubular heat exchanger comprises upper and lower heat exchanger tube sheets and a plurality of heat exchanger tube bundles, the heat exchanger tube sheets are sealingly welded with the inner wall of the front separation tank, the two ends of each heat exchanger tube bundle are connected with the heat exchanger tube sheets, the gas enters the heat exchanger tube bundle and is discharged from bottom to top, and each heat exchanger tube bundle is immersed in the cooling water; The same plane of the heat exchanger tube bundle is provided with a plurality of water injection holes, the cooling water is injected into the heat exchanger tube bundle through the water injection holes to form a water curtain, and the gas exchanges heat with the water curtain.

2. The high vacuum condensing gas-liquid separation device of claim 1, wherein, The same plane of the heat exchanger tube bundle is uniformly provided with a plurality of water injection holes, and a plurality of layers of water injection holes are arranged on different planes of the heat exchanger tube bundle, and the water injection holes on each heat exchanger tube bundle are staggered.

3. The high vacuum condensing gas-liquid separation device of claim 2, wherein, The distance between the adjacent two layers of water injection holes is 200mm.

4. The high vacuum condensing gas-liquid separation device of claim 3, wherein, The same plane of the heat exchanger tube bundle is uniformly provided with 3-4 water injection holes.

5. The high vacuum condensing gas-liquid separation device of claim 1, wherein, The top of the front separation tank is provided with a gas outlet, the lower side is provided with a gas inlet, the bottom is provided with a condensed water outlet, the upper side is provided with a cooling water inlet, and the other side is provided with a cooling water outlet.

6. The high vacuum condensing gas-liquid separation device of claim 5, wherein, The high-vacuum condensing gas-liquid separation device further comprises a negative pressure pump, the negative pressure pump is communicated with the upper end gas outlet of the front separation tank through a balance pipe, and the balance pipe is also communicated with the condensed water outlet.

7. The high vacuum condensing gas-liquid separation device of claim 6, wherein, The balance pipe is provided with a balance pipe adjusting valve.

Images