Compressed natural gas dryer

Abstract

The invention discloses a compressed natural gas dryer, and relates to the technical field of natural gas treatment.The compressed natural gas dryer comprises a support, a gas conveying pipe is installed on the support, a heat pipe mechanism and a condensation mechanism are further arranged on the support, one end of the gas conveying pipe is connected with a water removal mechanism, and the condensation mechanism comprises an evaporation box fixedly installed on the support; a condensation box is fixedly installed above the evaporation box, a snakelike circulating pipe communicated with the condensation box is further arranged above the evaporation box, heat dissipation fins are further fixedly installed between the evaporation box and the condensation box, a water inlet pipe and a flow guide pipe which are connected with a water removal mechanism are arranged on the evaporation box and the condensation box respectively, and an air conveying pipe is composed of a horizontal end and a vertical end. Through the design of the horizontal end and the vertical end of the gas conveying pipe, heat absorption of the heat conducting plate of the evaporation section and cooling medium circulation of the snakelike circulating pipe, a dual-condensation mechanism is formed, the natural gas cooling efficiency is improved, sufficient condensation of water vapor is ensured, and the problem that condensation of a traditional device is not thorough is solved.

Description

Technical Field

[0001] This invention relates to the field of natural gas processing technology, and more specifically to a compressed natural gas dryer. Background Technology

[0002] Compressed natural gas, as a clean, efficient, and low-carbon energy source, is widely used in vehicle fuel, industrial kilns, distributed energy systems, and urban gas peak shaving.

[0003] In the extraction, transportation, and end-use of natural gas, in order to meet the requirements of storage pressure and transportation standards, the pressure of natural gas needs to be increased to a high-pressure state by compressors. However, during this process, the saturated water vapor in the natural gas will concentrate as the pressure increases. If it is not dried, it will easily cause a series of problems in subsequent use.

[0004] In the practical application of condensing compressed natural gas drying technology, drying devices with shell-and-tube condensers as the core heat exchange element, as well as small-volume heat pipe drying devices adapted to low-flow scenarios, tend to have "dead zones" in the heat exchange channels when high-pressure natural gas enters the shell side at a certain flow rate. This is because the shell side of the shell-and-tube condenser is cylindrical and the heat exchange tubes are mostly uniformly arranged tube bundle structures. As a result, some airflow does not fully contact the heat exchange surface before flowing out, leading to incomplete condensation of water vapor. Furthermore, condensate accumulates on the heat exchange surface or in the pipes, covering the heat exchange fins, which reduces the effective heat exchange area and further reduces the heat exchange efficiency. Summary of the Invention

[0005] In view of the problems existing in the prior art, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to provide a compressed natural gas dryer. The problem it aims to solve is that the heat exchange tubes used in the transmission condenser are mostly uniformly arranged tube bundle structures, which causes some airflow to flow out before fully contacting the heat exchange surface, resulting in incomplete condensation of water vapor. Furthermore, condensate deposits on the heat exchange surface or inside the pipes, covering the heat exchange fins, which reduces the effective heat exchange area and further reduces the heat exchange efficiency.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a compressed natural gas dryer, comprising a support frame, on which a gas transmission pipe for conveying natural gas is installed, and the support frame is also provided with a heat pipe mechanism and a condensation mechanism for heat exchange and condensation, respectively, and one end of the gas transmission pipe is connected to a dehydration mechanism for drying natural gas; The condensation mechanism includes an evaporator fixedly mounted on a bracket, a condenser fixedly mounted above the evaporator, a serpentine circulation pipe connected to the condenser above the evaporator, heat dissipation fins arranged in a fixed manner between the evaporator and the condenser, and the end of the serpentine circulation pipe extending outside the evaporator passes through the heat dissipation fins in sequence. The evaporator and the condenser are respectively provided with a water inlet pipe and a guide pipe connected to the water removal mechanism. The gas supply pipe consists of a horizontal end and a vertical end. The horizontal end of the gas supply pipe extends into the evaporator and is connected to the vertical end. The vertical end of the gas supply pipe extends out of the evaporator and is located in the condenser.

[0008] In a preferred embodiment of the compressed natural gas dryer of the present invention, the heat pipe mechanism includes a heat insulation cylinder fixedly installed on a bracket, and the two ends of the heat insulation cylinder are respectively provided with an evaporation section and a condensation section, and the evaporation section and the condensation section are respectively provided with the horizontal end and the vertical end of the gas transmission pipe.

[0009] In a preferred embodiment of the compressed natural gas dryer of the present invention, heat-conducting plates arranged in a specific pattern are fixedly installed on the outer side of the evaporation section, and the end of the heat-conducting plate away from the evaporation section is fixedly installed on the horizontal end of the gas transmission pipe, and a compressor for conveying phase change working fluid is fixedly installed at the end of the evaporation section extending outside the heat insulation cylinder.

[0010] In a preferred embodiment of the compressed natural gas dryer of the present invention, one end of the condensing section extending into the heat insulation cylinder is connected to the evaporating section, and a water return cover is fixedly installed at one end of the condensing section extending outside the heat insulation cylinder, and the water return cover is connected to the evaporating section through the condensing section.

[0011] In a preferred embodiment of the compressed natural gas dryer of the present invention, the dehydration mechanism includes a dehydration tank fixedly installed on a bracket. The dehydration tank is provided with a drain pipe and an exhaust pipe that are connected to the dehydration tank. The exhaust pipe is located above the drain pipe. An air inlet pipe is fixedly installed at the top of the dehydration tank, and one end of the air inlet pipe that extends outside the dehydration tank is connected to a guide pipe.

[0012] In a preferred embodiment of the compressed natural gas dryer of the present invention, a water supply pipe is fixedly installed at the bottom of the dewatering tank, and one end of the drain pipe extending into the dewatering tank is connected to the water supply pipe. A return water pump connected to the inlet water pipe is provided at the end of the water supply pipe extending outside the dewatering tank, and a water pump is provided at the end of the drain pipe away from the water supply pipe.

[0013] In a preferred embodiment of the compressed natural gas dryer of the present invention, a water filter membrane that is fitted with the water filter membrane is fixedly installed in the water removal tank, and a guide cone is fixedly installed at one end of the air inlet pipe that passes through the water filter membrane, and the guide cone is located below the water filter membrane. The end of the exhaust pipe that extends into the water removal tank is located above the water filter membrane.

[0014] As a preferred embodiment of the compressed natural gas dryer of the present invention, a water filter plate is also fixedly installed in the water removal tank, and the water filter plate is located below the water filter membrane. The water filter plate has a ring-shaped array of water filter holes, and the water filter plate is also provided with a water guide cone corresponding to the flow guide cone.

[0015] In a preferred embodiment of the compressed natural gas dryer of the present invention, a water separator is fixedly installed on the water removal tank and below the water filter plate, and a water pipe filter head is fixedly installed at one end of the water supply pipe that passes through the water separator plate, and the water pipe filter head is located between the water filter plate and the water separator plate.

[0016] In summary, the present invention has at least one of the following beneficial effects: 1. This invention, through the design of the horizontal and vertical ends of the gas pipeline, combined with the heat absorption of the heat-conducting plate in the evaporation section and the circulation of the cooling medium in the serpentine circulation pipe, forms a dual condensation mechanism, which improves the cooling efficiency of natural gas, ensures that water vapor is fully condensed, and solves the problem of incomplete condensation in traditional devices.

[0017] 2. This invention recovers the heat of working fluid liquefaction by directly exchanging heat between the heat pipe condensation section and the serpentine circulation pipe. It also uses gravity and a compressor to drive the working fluid circulation and allows the condensate to be recycled, thus achieving the recovery of heat and water resources.

[0018] 3. In this invention, a water removal tank is equipped with a water filter membrane and a water filter disc for dual filtration and water removal, and is equipped with a water separator and a water pipe filter head to prevent impurities, ensuring that the natural gas dries to the required standard. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0020] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ; Figure 3 This is a structural diagram showing the installation of the heat pipe mechanism and the condensation mechanism of the present invention. Figure 4 This is a structural diagram showing the installation of the heat pipe mechanism and the gas delivery pipe according to the present invention; Figure 5 This is a structural diagram of the water removal mechanism of the present invention; Figure 6 This is a cross-sectional view of the water removal mechanism of the present invention.

[0021] Explanation of reference numerals in the attached figures: 1. Support frame; 2. Gas supply pipe; 3. Evaporator; 301. Water inlet pipe; 4. Condenser; 401. Flow guide pipe; 5. Serpentine circulation pipe; 6. Heat dissipation fins; 7. Insulation cylinder; 8. Evaporation section; 801. Heat conduction plate; 802. Compressor; 9. Condenser section; 901. Water return cover; 10. Water removal tank; 1001. Drain pipe; 1002. Exhaust pipe; 11. Gas inlet pipe; 12. Water supply pipe; 1201. Water baffle; 1202. Water pipe filter head; 13. Water return pump; 14. Water pump; 15. Water filter membrane; 16. Flow guide cone; 17. Water filter tray; 1701. Water guide cone. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] This invention discloses a compressed natural gas dryer. Example 1

[0024] Reference Figure 1-6This invention provides a first embodiment of a compressed natural gas dryer, comprising a support 1, on which a gas delivery pipe 2 for transporting natural gas is mounted. The support 1 also includes a heat pipe mechanism for heat exchange and condensation, and a condensation mechanism. One end of the gas delivery pipe 2 is connected to a dehydration mechanism for drying the natural gas. The condensation mechanism includes an evaporator 3 fixedly mounted on the support 1, and a condensation box 4 fixedly mounted above the evaporator 3. A serpentine circulation pipe 5 connected to the condensation box 4 is also provided above the evaporator 3. Distributed heat dissipation fins 6 are fixedly mounted between the evaporator 3 and the condensation box 4, with the end of the serpentine circulation pipe 5 extending outside the evaporator 3 passing through the heat dissipation fins 6. The evaporator 3 and the condensation box 4 are respectively provided with a water inlet pipe 301 and a guide pipe 401 connected to the dehydration mechanism. The gas delivery pipe 2 consists of a horizontal end and a vertical end, with the horizontal end of the gas delivery pipe 2 extending into the evaporator 3 and connected to the vertical end. The vertical end of the 2 extends outside the evaporator 3 and is located in the condenser 4. The bracket 1 serves as the basic support structure for the entire dryer, stably supporting all functional components. The gas pipe 2 is responsible for transporting natural gas and achieves continuous and stable natural gas delivery through an external pump. The evaporator 3 is equipped with a baffle plate to guide the even distribution of circulating condensate inside. The condenser 4 maintains a slightly negative pressure environment to promote water vapor condensation. The serpentine circulation pipe 5 can cooperate with the heat dissipation fins 6 to ensure a tight fit, reduce thermal resistance, and form a composite heat dissipation structure. The water inlet pipe 301 is equipped with a shut-off valve to control the flow rate of circulating water. The guide pipe 401 can discharge natural gas and condensed water vapor from the condenser 4. The length of the gas pipe 2 is adapted to the size of the evaporator 3 to ensure that the natural gas can fully exchange heat inside the box. The vertical end matches the heat exchange space inside the condenser 4, thereby ensuring that the natural gas flowing out from the gas pipe 2 can fully enter the low-temperature area of ​​the condenser 4 to promote water vapor condensation and enhance the water vapor condensation effect.

[0025] The heat pipe mechanism includes a heat insulation cylinder 7 fixedly installed on the bracket 1. The heat insulation cylinder 7 has an evaporation section 8 and a condensation section 9 at its two ends, respectively. The evaporation section 8 and the condensation section 9 are respectively set to the horizontal end and the vertical end of the gas transmission pipe 2. The heat insulation cylinder 7 can effectively reduce the heat exchange between the heat pipe and the external environment. The evaporation section 8 is parallel to and attached to the outer wall of the horizontal end of the gas transmission pipe 2, and the condensation section 9 is parallel to and attached to the outer wall of the vertical end of the gas transmission pipe 2. The two transfer the heat of the natural gas in the gas transmission pipe 2 to the inside of the heat pipe through the "wall heat transfer" method, realizing targeted heat exchange.

[0026] Heat-conducting plates 801 are fixedly installed on the outer side of the evaporation section 8, and the end of the heat-conducting plate 801 away from the evaporation section 8 is fixedly installed on the horizontal end of the gas transmission pipe 2. A compressor 802 for transporting phase change working fluid is fixedly installed at the end of the evaporation section 8 that extends outside the heat insulation cylinder 7. The heat-conducting plate 801 can greatly increase the contact area between the evaporation section 8 and the gas transmission pipe 2 to ensure heat transfer stability. The compressor 802 can automatically adjust the output power according to the natural gas temperature in the gas transmission pipe 2 to drive the working fluid to circulate in the heat pipe and improve the heat transfer response speed.

[0027] One end of the condensing section 9 extends into the heat insulation cylinder 7 and is connected to the evaporating section 8. A return water cover 901 is fixedly installed at the other end of the condensing section 9 extending outside the heat insulation cylinder 7. The return water cover 901 is connected to the evaporating section 8 through the condensing section 9. The condensing section 9 is connected to the evaporating section 8 by seamless welding to form a closed working fluid circulation channel. The function of the return water cover 901 is to collect the liquefied phase change working fluid in the condensing section 9. Through the synergistic effect of gravity and the compressor 802, the working fluid is guided to flow back stably to the evaporating section 8, avoiding the working fluid stagnation from affecting the heat transfer efficiency and preventing clogging.

[0028] The dewatering mechanism includes a dewatering tank 10 fixedly installed on a bracket 1. The dewatering tank 10 is equipped with a drain pipe 1001 and an exhaust pipe 1002 connected to the dewatering tank 10. The exhaust pipe 1002 is located above the drain pipe 1001. An air inlet pipe 11 is fixedly installed at the top of the dewatering tank 10, and one end of the air inlet pipe 11 extends outside the dewatering tank 10 and is connected to the guide pipe 401. The inside of the dewatering tank 10 is treated with an anti-corrosion coating to meet the separation requirements of high-pressure liquid natural gas. It is also equipped with an emergency pressure relief safety valve. The drain pipe 1001 is equipped with a check valve to prevent the condensate transported by the air inlet pipe 11 from flowing back. The exhaust pipe 1002 is connected to the subsequent natural gas transmission pipeline to output dry natural gas. The dewatering tank 10 mainly uses the gas-liquid density difference to achieve gravity sedimentation separation.

[0029] A water supply pipe 12 is fixedly installed at the bottom of the water tank 10, and one end of the drain pipe 1001 extends into the water tank 10 and is connected to the water supply pipe 12. The end of the water supply pipe 12 extending outside the water tank 10 is equipped with a return water pump 13 connected to the inlet pipe 301. The end of the drain pipe 1001 away from the water supply pipe 12 is equipped with a water pump 14. The water supply pipe 12 can discharge the liquefied water vapor in the water tank 10, and the drain pipe 1001 serves as a branch of the water supply pipe 12 for diversion. The return water pump 13 can pressurize and transport the condensate in the water tank to the inlet pipe 301 of the evaporator 3 to realize the recycling of condensate and reduce water consumption. The water pump 14 can discharge excess condensate vapor.

[0030] The dewatering tank 10 is also fixedly installed with a filter membrane 15 that fits the filter membrane 15 with a clearance. A guide cone 16 is fixedly installed at one end of the air inlet pipe 11 that passes through the filter membrane 15. The guide cone 16 is located below the filter membrane 15. One end of the exhaust pipe 1002 that extends into the dewatering tank 10 is located above the filter membrane 15. The filter membrane 15 is a high-polymer hydrophilic composite membrane that can trap small droplets in the natural gas. The function of the guide cone 16 is to disperse the liquid-containing natural gas transported from the guide pipe 401 into an umbrella-shaped airflow, increase the contact area between the natural gas and the filter membrane 15, and improve the initial dewatering effect.

[0031] In addition to the water tank 10, a water filter plate 17 is also fixedly installed, and the water filter plate 17 is located below the water filter membrane 15. The water filter plate 17 has a ring array of water filter holes. The water filter plate 17 is also provided with a water guide cone 1701 corresponding to the flow guide cone 16. The water filter plate 17 can further filter the liquefied water vapor through the water filter holes. The function of the water guide cone 1701 is to receive the airflow dispersed by the flow guide cone 16 and guide the intercepted water droplets to flow along the cone surface to the edge of the water filter plate 17, and finally flow into the water supply pipe 12.

[0032] A water separator 1201 is fixedly installed on the water tank 10 and below the water filter plate 17. A water pipe filter head 1202 is fixedly installed at one end of the water pipe 12 that passes through the water separator 1201. The water pipe filter head 1202 is located between the water filter plate 17 and the water separator 1201. The water separator 1201 is used to separate the water accumulation area below the water filter plate 17 from the inlet of the water pipe 12 to prevent the water accumulation at the bottom from being disturbed by airflow. The water pipe filter head 1202 further prevents tiny impurities in the water from entering the return water pump 13 and extends the service life of the pump.

[0033] In the process of drying compressed natural gas using this device, the pre-treated natural gas is first transported under pressure by an external pump and enters the evaporator 3 through the gas pipeline 2. During the horizontal flow, heat is absorbed by the evaporator section 8, the temperature of the natural gas decreases, and the water vapor in it begins to condense. At the same time, the cooling medium in the serpentine circulation pipe 5 circulates between the evaporator 3 and the condenser 4, further reducing the temperature of the natural gas and promoting the condensation of water vapor into liquid water. The liquid-containing natural gas then flows to the dewatering tank 10 through the guide pipe 401. The phase change working fluid in the evaporation section 8 absorbs heat from the natural gas and vaporizes. It flows along the heat pipe to the condensation section 9. In the condensation section 9, the working fluid exchanges heat with the serpentine circulation pipe 5 between the evaporation box 3 and the condensation box 4. After releasing heat, it liquefies and, with the help of gravity and the action of the compressor 802, flows back to the evaporation section 8 along the pipe wall. It continues to circulate to maintain efficient heat exchange. After the liquefied natural gas enters the dewatering tank 10, it is first filtered by the water filter membrane 15. Tiny droplets are trapped, while larger droplets are intercepted by the water filter plate 17. The water is then collected by the water guide cone 1701 and sent to the water supply pipe 12. The dried natural gas is then output through the exhaust pipe 1002. Meanwhile, the condensate, under the action of the return water pump 13, is transported through the water supply pipe 12 to the water inlet pipe 301 of the evaporator 3 to assist the condensation process of the natural gas and realize the recycling of water resources.

[0034] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A compressed natural gas dryer, characterized in that: Includes a support (1), on which a gas pipeline (2) for transporting natural gas is installed. The support (1) is also provided with a heat pipe mechanism and a condensation mechanism for heat exchange and condensation. One end of the gas pipeline (2) is connected to a dehydration mechanism for drying natural gas. The condensation mechanism includes an evaporator (3) fixedly installed on a bracket (1), a condenser (4) fixedly installed above the evaporator (3), a serpentine circulation pipe (5) connected to the condenser (4) above the evaporator (3), heat dissipation fins (6) arranged and fixedly installed between the evaporator (3) and the condenser (4), and the end of the serpentine circulation pipe (5) extending outside the evaporator (3) passes through the heat dissipation fins (6) in sequence. The evaporator (3) and the condenser (4) are respectively provided with a water inlet pipe (301) and a guide pipe (401) connected to the water removal mechanism. The gas supply pipe (2) consists of a horizontal end and a vertical end. The horizontal end of the gas supply pipe (2) extends into the evaporator (3) and is connected to the vertical end. The vertical end of the gas supply pipe (2) extends outside the evaporator (3) and is located in the condenser (4).

2. The compressed natural gas dryer according to claim 1, characterized in that, The heat pipe mechanism includes a heat insulation cylinder (7) fixedly installed on the bracket (1), and the heat insulation cylinder (7) is provided with an evaporation section (8) and a condensation section (9) at both ends, and the evaporation section (8) and the condensation section (9) are respectively provided with the horizontal end and the vertical end of the gas transmission pipe (2).

3. The compressed natural gas dryer according to claim 2, characterized in that, A heat-conducting plate (801) is fixedly installed on the outside of the evaporation section (8), and the end of the heat-conducting plate (801) away from the evaporation section (8) is fixedly installed on the horizontal end of the gas transmission pipe (2). A compressor (802) for conveying phase change working fluid is fixedly installed on the end of the evaporation section (8) extending outside the heat insulation cylinder (7).

4. The compressed natural gas dryer according to claim 2, characterized in that, The condensing section (9) extends into the heat insulation cylinder (7) and is connected to the evaporating section (8). A water return cover (901) is fixedly installed at the end of the condensing section (9) extending outside the heat insulation cylinder (7), and the water return cover (901) is connected to the evaporating section (8) through the condensing section (9).

5. The compressed natural gas dryer according to claim 1, characterized in that, The water removal mechanism includes a water removal tank (10) fixedly installed on a bracket (1). The water removal tank (10) is provided with a drain pipe (1001) and an exhaust pipe (1002) connected to the water removal tank (10). The exhaust pipe (1002) is located above the drain pipe (1001). An air inlet pipe (11) is fixedly installed at the top of the water removal tank (10), and the end of the air inlet pipe (11) extending outside the water removal tank (10) is connected to a guide pipe (401).

6. The compressed natural gas dryer according to claim 5, characterized in that, The bottom end of the water removal tank (10) is also fixedly installed with a water supply pipe (12), and the end of the drain pipe (1001) extending into the water removal tank (10) is connected to the water supply pipe (12). The end of the water supply pipe (12) extending outside the water removal tank (10) is provided with a return water pump (13) connected to the water inlet pipe (301). The end of the drain pipe (1001) away from the water supply pipe (12) is provided with a water pump (14).

7. The compressed natural gas dryer according to claim 5, characterized in that, The water removal tank (10) is also fixedly installed with a filter membrane (15) that fits the water removal tank (10) with a gap. The air inlet pipe (11) is fixedly installed with a flow guide cone (16) at one end through the filter membrane (15). The flow guide cone (16) is located below the filter membrane (15). The exhaust pipe (1002) extends into the water removal tank (10) and is located above the filter membrane (15).

8. The compressed natural gas dryer according to claim 7, characterized in that, The water removal tank (10) is also fixedly installed with a water filter plate (17), and the water filter plate (17) is located below the water filter membrane (15). The water filter plate (17) has a ring array of water filter holes, and the water filter plate (17) is also provided with a water guide cone (1701) corresponding to the guide cone (16).

9. The compressed natural gas dryer according to claim 6, characterized in that, A water separator (1201) is fixedly installed on the water removal tank (10) and below the water filter plate (17). A water pipe filter head (1202) is fixedly installed at one end of the water pipe (12) that passes through the water separator (1201). The water pipe filter head (1202) is located between the water filter plate (17) and the water separator (1201).

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