A device for transporting light hydrocarbon gas at low temperature

Abstract

The utility model relates to a kind of light hydrocarbon gas conveying equipment at low temperature, and specifically relates to a kind of light hydrocarbon gas conveying equipment at low temperature.The utility model discloses a kind of light hydrocarbon gas conveying equipment at low temperature, to solve the condensation reduction problem in light hydrocarbon mixed gas conveying process.The utility model includes raw material tank 1, air tank 2, gas making tank 3, buffer tank 4 and reflux tank 5, and its characterized in that the raw material outlet 1-5 of raw material tank 1 is connected with the raw material inlet 3-6 of gas making tank 3, the air inlet 3-3 of gas making tank 3 is connected with the air outlet 2-4 of air tank 2, the condensate inlet 3-2 of gas making tank 3 is connected with the vent 5-7 of reflux tank 5, the mixed gas outlet 3-1 of gas making tank 3 is connected with the mixed gas inlet 4-2 of buffer tank 4, the filter liquid inlet 3-5 of gas making tank 3 is connected with the vent 4-6 of buffer tank 4, and the mixed gas outlet 4-4 of buffer tank 4 is connected with the mixed gas inlet 5-1 of reflux tank 5.

Description

Technical Field

[0001] This utility model relates to the field of light hydrocarbon gas preparation and transportation technology, specifically to a light hydrocarbon gas transportation device at low temperature. Background Technology

[0002] During the atmospheric compression of light hydrocarbon fuel gas, there is a characteristic of condensation. When the pipeline transport distance of the premixed light hydrocarbon fuel gas is too long or the ambient temperature is low, a gas-liquid condensation and reduction phenomenon will occur. The reduced mixed condensate will block the gas pipeline and may cause deflagration, which may cause danger.

[0003] Furthermore, the above statements are only used to provide background information related to this application and do not necessarily constitute prior art. Utility Model Content

[0004] This utility model discloses a low-temperature light hydrocarbon gas conveying device to solve the condensation and reduction problem during the conveying of light hydrocarbon mixed-air gas.

[0005] This utility model includes a raw material tank 1, an air tank 2, a gas generator 3, a buffer tank 4, and a reflux tank 5. The raw material outlet 1-5 of the raw material tank 1 is connected to the raw material inlet 3-6 of the gas generator 3; the air inlet 3-3 of the gas generator 3 is connected to the air outlet 2-4 of the air tank 2; the condensate inlet 3-2 of the gas generator 3 is connected to the first vent 5-7 of the reflux tank 5; the first mixed-air outlet 3-1 of the gas generator 3 is connected to the first mixed-air inlet 4-2 of the buffer tank 4; the filtrate inlet 3-5 of the gas generator 3 is connected to the second vent 4-6 of the buffer tank 4; and the second mixed-air outlet 4-4 of the buffer tank 4 is connected to the second mixed-air inlet 5-1 of the reflux tank 5.

[0006] As a preferred embodiment, the present invention also includes a heating tank 6, wherein the third mixing inlet 6-1 of the heating tank 6 is connected to the third mixing outlet 5-2 of the reflux tank 5.

[0007] As another preferred embodiment, the raw material tank 1 of this utility model is provided with a raw material tank opening 1-1, a first air inlet 1-2, a level gauge connection port, a pressure gauge connection port, a third vent 1-4, and a raw material outlet 1-5. The first air inlet 1-2 is connected to a nitrogen tank, the level gauge connection port is connected to a first level gauge 1-3, and the pressure gauge connection port is connected to a first pressure gauge 1-6.

[0008] As another preferred embodiment, the air tank 2 of this utility model is provided with a pressure relief port, a second air inlet 2-2, a pressure gauge interface, an air outlet 2-4 and a fourth vent 2-6. The pressure relief port is connected to a pressure relief valve 2-1, the pressure gauge interface is connected to a second pressure gauge 2-3, and the second air inlet 2-2 is connected to an air compressor.

[0009] As another preferred embodiment, the gas generator 3 of this utility model is provided with a first mixed air outlet 3-1, a condensate inlet 3-2, an air inlet 3-3, a filtrate inlet 3-5, a raw material inlet 3-6, a level gauge interface, and a fifth vent 3-9. The lower part of the gas generator 3 is equipped with a first hot water coil 3-7, and the level gauge interface is connected to the second level gauge 3-8; A condensate inlet 3-2 is connected to a condensate riser, and the lower end of the condensate riser is placed in the middle of the gas generator 3. A flap 3-4 is provided in the middle of the gas generator 3. The inner end of the flap 3-4 is fixedly connected to the upper end of the downward extending connecting rod and is hinged to the lower outer wall of the condensate vertical pipe. The lower end of the connecting rod is connected to the float 3-10. Air inlet 3-3 is connected to air outlet 2-4; raw material inlet 3-6 is connected to raw material outlet 1-5; first mixed air outlet 3-1 is connected to first mixed air inlet 4-2; filtrate inlet 3-5 is connected to second vent 4-6; condensate inlet 3-2 is connected to first vent 5-7.

[0010] As another preferred embodiment, the buffer tank 4 of this utility model is provided with a first mixing air inlet 4-2, a second mixing air outlet 4-4, and a second vent 4-6. The second vent 4-6 is located at the lower end of the buffer tank 4. The first mixing air inlet 4-2 is located at the upper part of one side of the buffer tank 4. The second mixing air outlet 4-4 is located at the upper part of the other side of the buffer tank 4, below the first mixing air inlet 4-2. The second mixing air outlet 4-4 is connected to the gas filter 4-3 through an outlet L-shaped pipe inside the buffer tank 4. The first mixing air inlet 4-2 is connected to the upper end of the inlet L-shaped pipe, and the lower end of the inlet L-shaped pipe is located in the lower part of the buffer tank 4. The buffer tank 4 is provided with a cross baffle 4-5 in the middle. The cross baffle 4-5 includes multiple inclined baffles that are symmetrically arranged on both sides and tilted from top to bottom. The inclined baffles on the same side are parallel to each other and have equal spacing. An opening is provided on one side of the inclined baffle, the openings of the inclined baffles on the same side are located on the same side, and the openings of the inclined baffles on both sides are located on opposite sides.

[0011] Secondly, the reflux tank 5 of this utility model is provided with a second mixed air inlet 5-1, a third mixed air outlet 5-2, a level gauge interface, a first temperature acquisition port 5-5, and a first vent 5-7. The second mixed air inlet 5-1 is located at the upper end of the reflux tank 5, the third mixed air outlet 5-2 is located at the upper right side of the reflux tank 5, the level gauge interface is located at the lower right side of the reflux tank 5, the first temperature acquisition port 5-5 is located at the lower left side of the reflux tank 5, and the first vent 5-7 is located at the end of the reflux tank 5. A filter device 5-3 is provided in the middle of the reflux tank 5, a second hot water coil 5-6 is provided in the lower part of the reflux tank 5, and the level gauge interface is connected to a third level gauge 5-4.

[0012] In addition, the heating tank 6 of this utility model is provided with a third mixing air inlet 6-1, a fourth mixing air outlet 6-2, a second temperature acquisition port 6-3, a level gauge interface, and a sixth vent 6-6. The third mixing air inlet 6-1 and the fourth mixing air outlet 6-2 are located at the upper end of the heating tank 6. A mixing air inlet pipe is connected to the third mixing air inlet 6-1, and the lower end of the mixing air inlet pipe is located in the middle of the heating tank 6. The second temperature acquisition port 6-3 is located in the lower left part of the heating tank 6. The level gauge interface is located in the lower right part of the heating tank 6. The sixth vent 6-6 is located at the lower end of the heating tank 6. The level gauge interface is connected to the fourth level gauge 6-4. A third hot water coil 6-5 is provided in the lower part of the heating tank 6.

[0013] The beneficial effects of this utility model are: The air tank 2 and raw material tank 1 of this utility model are used to transport raw materials to the gas generator 3. The first hot water coil 3-7 below the gas generator 3 heats and catalyzes the formation of light hydrocarbon mixed air gas. The mixed air gas enters the buffer tank 4. The buffer tank 4 contains a gas filter 4-3. The filtered light hydrocarbon mixed air gas enters the return tank 5. The second hot water coil 5-6 below the return tank 5 assists in the re-gasification of the light hydrocarbon mixed air gas. The light hydrocarbon mixed air gas that is not gasified in time is transported to the gas generator 3 to be re-gasified.

[0014] This invention provides a conveying device for light hydrocarbon fuel gas from preparation to use at low temperatures, which solves the problem of condensate reduction during the low-pressure conveying of light hydrocarbon fuel gas, and can recycle the reduced light hydrocarbon liquid, thereby improving safety, reducing costs, and saving energy and reducing emissions. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The scope of protection of the present invention is not limited to the following description.

[0016] Figure 1 is a schematic diagram of the overall structure of this utility model.

[0017] Figure 2 is a schematic diagram of the raw material tank structure of this utility model.

[0018] Figure 3 This is a schematic diagram of the air tank structure of this utility model.

[0019] Figure 4 This is a schematic diagram of the gas generator structure of this utility model.

[0020] Figure 5 is a schematic diagram of the buffer tank structure of this utility model.

[0021] Figure 6 is a schematic diagram of the reflux tank structure of this utility model.

[0022] Figure 7 This is a schematic diagram of the heating tank structure of this utility model.

[0023] In the diagram: 1. Raw material tank; 1-1. Raw material tank opening; 1-2. First air inlet; 1-3. First liquid level gauge; 1-4. Third vent; 1-5. Raw material outlet; 2. Air tank; 2-1. Pressure relief valve; 2-2. Second air inlet; 2-3. Second pressure gauge; 2-4. Air outlet; 2-6. Fourth vent; 3. Gas generator; 3-1. First mixed air outlet; 3-2. Condensate inlet; 3-3. Air inlet; 3-4. Flip plate; 3-5. Filtrate inlet; 3-6. Raw material inlet; 3-7. First hot water coil; 3-8. Second liquid level gauge; 3-9. Fifth vent; 4. Buffer 4-2. First mixed air inlet; 4-3. Gas filter; 4-4. Second mixed air outlet; 4-5. Cross baffle; 4-6. Second vent; 5. Return tank; 5-1. Second mixed air inlet; 5-2. Third mixed air outlet; 5-3. Filter device; 5-4. Third level gauge; 5-5. First temperature acquisition port; 5-6. Second hot water coil; 5-7. First vent; 6. Heating tank; 6-1. Third mixed air inlet; 6-2. Fourth mixed air outlet; 6-3. Second temperature acquisition port; 6-4. Fourth level gauge; 6-5. Third hot water coil; 6-6. Sixth vent.

[0024] Figure 8 is a schematic diagram of the overall pipeline and valve arrangement of the light hydrocarbon gas low-pressure transmission device of this utility model.

[0025] Figure 9 is a schematic diagram of the three-stage natural gas depressurization principle of this utility model.

[0026] Figure 10 This is a diagram illustrating the dual-fuel switching between natural gas and light hydrocarbons according to this utility model.

[0027] Figure 11 This is a diagram of the dual-backup light hydrocarbon dual-backup pressure reducing pipeline of this utility model.

[0028] In the diagram: 10-1, Natural Gas Filter; 10-2, Shut-off Valve; 10-3, Natural Gas Pressure Reducing Valve; 10-4, Natural Gas Pipeline Pressure Gauge; 10-5, Natural Gas Pipeline Overpressure Relief Valve; 10-6, Butterfly Valve; 10-7, Check Valve; 20-1, Dual-Fuel Pipeline Pressure Gauge; 20-2, Dual-Fuel Pipeline Shut-off Valve; 20-3, Dual-Fuel Pipeline Check Valve; 30-1, Shut-off Valve; 30-2, Light Hydrocarbon Pressure Reducing Valve; 30-3, Pressure Gauge; 30-4, Light Hydrocarbon Pressure Regulating Valve; 30-5, Butterfly Valve; 30-6, Check Valve. Detailed Implementation

[0029] As shown in the figure, this utility model includes a raw material tank 1, an air tank 2, a gas generator 3, a buffer tank 4, and a reflux tank 5. The raw material outlet 1-5 of the raw material tank 1 is connected to the raw material inlet 3-6 of the gas generator 3. The air inlet 3-3 of the gas generator 3 is connected to the air outlet 2-4 of the air tank 2. The condensate inlet 3-2 of the gas generator 3 is connected to the first vent 5-7 of the reflux tank 5. The first mixed air outlet 3-1 of the gas generator 3 is connected to the first mixed air inlet 4-2 of the buffer tank 4. The filtrate inlet 3-5 of the gas generator 3 is connected to the second vent 4-6 of the buffer tank 4. The second mixed air outlet 4-4 of the buffer tank 4 is connected to the second mixed air inlet 5-1 of the reflux tank 5.

[0030] It also includes a heating tank 6, whose third mixing inlet 6-1 is connected to the third mixing outlet 5-2 of the return tank 5. The heating tank 6 in this invention increases the gas delivery distance while ensuring that the vaporization rate of the mixed gas does not decrease and the pressure remains stable when it reaches the user end. Increased delivery distance allows for a wider range of applications for the light hydrocarbon gas, and a high vaporization rate and stable pressure represent greater safety, greatly reducing the occurrence of deflagration and sudden pressure changes. In this invention, the air tank 2 and raw material tank 1 supply raw materials to the gas generator 3. The first hot water coil 3-7 below the gas generator 3 heats and catalyzes the formation of light hydrocarbon mixed gas. The mixed gas enters the buffer tank 4, which contains a gas filter 4-3. The filtered light hydrocarbon mixed gas enters the return tank 5. The second hot water coil 5-6 below the return tank 5 assists in the re-vaporization of the light hydrocarbon mixed gas. Light hydrocarbon mixed gas that is not vaporized in time is transported to the gas generator 3 for re-gasification. The fully vaporized light hydrocarbon mixed gas then enters the heating tank 6 for re-vaporization before reaching the user end.

[0031] The raw material tank 1 is equipped with a raw material tank opening 1-1, a first air inlet 1-2, a level gauge connection port, a pressure gauge connection port, a third vent 1-4, and a raw material outlet 1-5. The first air inlet 1-2 is connected to a nitrogen tank, the level gauge connection port is connected to a first level gauge 1-3, and the pressure gauge connection port is connected to a first pressure gauge 1-6.

[0032] Light hydrocarbon raw material enters raw material tank 1 through raw material tank inlet 1-1. The first air inlet 1-2 is connected to a nitrogen tank, which injects nitrogen into raw material tank 1 to provide pressure for the transfer of the light hydrocarbon raw material. A nitrogen supply valve can be installed at the outlet of the nitrogen tank to control the nitrogen pressure injected into raw material tank 1. The level gauge connection port is connected to the first level gauge 1-3, and the pressure gauge connection port is connected to the first pressure gauge 1-6. When the level gauge indicates excessive liquid or the pressure in raw material tank 1 is too high, the third vent port 1-4 opens.

[0033] The air tank 2 is equipped with a pressure relief port, a second air inlet 2-2, a pressure gauge interface, an air outlet 2-4, and a fourth vent 2-6. The pressure relief port is connected to a pressure relief valve 2-1, the pressure gauge interface is connected to a second pressure gauge 2-3, and the second air inlet 2-2 is connected to an air compressor. The second pressure gauge 2-3 displays the tank pressure; when the pressure is too high, it is released through the pressure relief valve 2-1.

[0034] Because compressed air contains moisture, the compression process increases the air density, causing some moisture to condense and adhere to the inner wall of air tank 2. Air tank 2 is equipped with a fourth vent 2-6 to periodically drain the accumulated water.

[0035] Air tank 2 is used to buffer pressure fluctuations in the air entering air tank 3. At the same time, it purifies the air. After the compressed air enters air tank 2, the flow rate slows down, and oil, water and impurities settle to the bottom due to gravity.

[0036] The gas generator 3 is equipped with a first mixed air outlet 3-1, a condensate inlet 3-2, an air inlet 3-3, a filtrate inlet 3-5, a raw material inlet 3-6, a level gauge interface, and a fifth vent 3-9. The lower part of the gas generator 3 is equipped with a first hot water coil 3-7, and the level gauge interface is connected to the second level gauge 3-8; A condensate inlet 3-2 is connected to a condensate riser, and the lower end of the condensate riser is placed in the middle of the gas generator 3. A flap 3-4 is provided in the middle of the gas generator 3. The inner end of the flap 3-4 is fixedly connected to the upper end of the downward extending connecting rod and is hinged to the lower outer wall of the condensate vertical pipe. The lower end of the connecting rod is connected to the float 3-10. Air inlet 3-3 is connected to air outlet 2-4; raw material inlet 3-6 is connected to raw material outlet 1-5; first mixed air outlet 3-1 is connected to first mixed air inlet 4-2; filtrate inlet 3-5 is connected to second vent 4-6; condensate inlet 3-2 is connected to first vent 5-7. A pump can be installed on the pipeline between the first vent 5-7 and the condensate inlet 3-2 to transport the condensate in the return tank 5 to the gas generator 3.

[0037] The gas generator 3 can be a gas generator (including a flapper and a float) with patent number 202110383932.9.

[0038] The buffer tank 4 is provided with a first mixing air inlet 4-2, a second mixing air outlet 4-4, and a second vent 4-6. The second vent 4-6 is located at the lower end of the buffer tank 4. The first mixing air inlet 4-2 is located on the upper part of one side of the buffer tank 4. The second mixing air outlet 4-4 is located on the upper part of the other side of the buffer tank 4, below the first mixing air inlet 4-2. The second mixing air outlet 4-4 is connected to the gas filter 4-3 through an outlet L-shaped pipe inside the buffer tank 4. The first mixing air inlet 4-2 is connected to the upper end of the inlet L-shaped pipe, and the lower end of the inlet L-shaped pipe is located in the lower part of the buffer tank 4. The buffer tank 4 is provided with a cross baffle 4-5 in the middle. The cross baffle 4-5 includes multiple inclined baffles that are symmetrically arranged on both sides and tilted from top to bottom. The inclined baffles on the same side are parallel to each other and have equal spacing. An opening is provided on one side of the inclined baffle, the openings of the inclined baffles on the same side are located on the same side, and the openings of the inclined baffles on both sides are located on opposite sides.

[0039] The buffer tank filters supersaturated light hydrocarbon mixtures. Cross baffles effectively block the light hydrocarbon mixture entering the buffer tank, trapping the supersaturated light hydrocarbons. As the mixture rises, the cross baffles effectively trap supersaturated gas and residual liquid water particles, which are then further filtered by a gas filter to remove liquid and small particulate impurities.

[0040] Gas filter 4-3 filters the liquid and small particulate impurities again.

[0041] The second vent 4-6 transports the filtered light hydrocarbon liquid back to the gas generator 3 for regasification.

[0042] A pump can be installed on the pipeline between the second vent 4-6 and the filtrate inlet 3-5 to transfer the filtrate in the buffer tank 4 to the gas generator 3.

[0043] The buffer tank 4 can be the "mixed-air buffer tank" (including cross baffles and gas filter) in the "gas generator with patent number 202110383932.9".

[0044] The reflux tank 5 is equipped with a second mixed-air inlet 5-1, a third mixed-air outlet 5-2, a level gauge interface, a first temperature acquisition port 5-5, and a first vent 5-7. The second mixed-air inlet 5-1 is located at the upper end of the reflux tank 5, the third mixed-air outlet 5-2 is located at the upper right side of the reflux tank 5, the level gauge interface is located at the lower right side of the reflux tank 5, the first temperature acquisition port 5-5 is located at the lower left side of the reflux tank 5, and the first vent 5-7 is located at the end of the reflux tank 5. A filter device 5-3 is installed in the middle of the reflux tank 5, a second hot water coil 5-6 is installed in the lower part of the reflux tank 5, and the level gauge interface is connected to a third level gauge 5-4.

[0045] The return tank is equipped with a filter device 5-3 for secondary filtration of the mixed air gas (filtering out liquid light hydrocarbons) and secondary heating to maintain the vaporization state of the mixed air gas. At the same time, excess light hydrocarbon liquid is transported back to the gas generator 3 to generate gas again.

[0046] The reflux tank 5 can be the "filter tank" in "Gas Generator of Patent 202110383932.9".

[0047] The heating tank 6 is provided with a third mixing air inlet 6-1, a fourth mixing air outlet 6-2, a second temperature acquisition port 6-3, a level gauge interface, and a sixth vent 6-6. The third mixing air inlet 6-1 and the fourth mixing air outlet 6-2 are located at the upper end of the heating tank 6. A mixing air inlet pipe is connected to the third mixing air inlet 6-1, and the lower end of the mixing air inlet pipe is located in the middle of the heating tank 6. The second temperature acquisition port 6-3 is located at the lower left of the heating tank 6. The level gauge interface is located at the lower right of the heating tank 6. The sixth vent 6-6 is located at the lower end of the heating tank 6. The level gauge interface is connected to the fourth level gauge 6-4, and the lower part of the heating tank 6 is equipped with a third hot water coil 6-5.

[0048] The heating tank 6 is used when the gas production site is far from the gas consumption end. One or more heating tanks 6 are installed along the gas transmission route to treat a small amount of condensate in the gas pipeline, so as to ensure the gasification rate and stability of the gas mixture at the gas consumption end.

[0049] Due to the physical properties of light hydrocarbon mixed gas, the pipeline transportation distance of the premixed light hydrocarbon mixed gas should not be too long, and the ambient temperature should not be too low. Otherwise, a gas-liquid reduction phenomenon will occur, affecting the use of user equipment. This utility model sets up a reflux tank 5 and a heating tank 6 to solve the problem that the mixed gas cannot be transported over long distances.

[0050] like Figure 1 As shown in the schematic diagram of the overall structure of this utility model, during gas generation, the air in the air tank 2 enters the upper cavity of the gas generating tank 3 through the air outlet 2-4 and the air inlet 3-3, and the nitrogen enters the raw material tank 2 through the first air inlet 1-2, increasing the pressure inside the raw material tank 2.

[0051] The light hydrocarbon raw liquid enters the lower cavity of the gasifier 3 through the raw material outlet 1-5 and the raw material inlet 3-6. The first hot water coil 3-7 at the bottom of the gasifier 3 is heated to the specified temperature, the raw liquid is vaporized, and the flapper 3-4 and float 3-10 act accordingly (the working principle of flapper 3-4 and float 3-10 can be found in the working process description of "flapper" and "float" in "Gasifier of 202110383932.9").

[0052] The fully mixed air gas is filtered once through gas filter 4-3. The filtered gas enters the return tank 5 through the second mixed air outlet 4-4 and the second mixed air inlet 5-1. At this time, the temperature of the mixed air gas drops and condensation occurs. Temperature data is collected at the first temperature acquisition port 5-5. When the temperature is low, the second hot water coil 5-6 heats up the gas to help maintain the vaporization state of the mixed air gas. The amount of condensate is observed through the third liquid level gauge 5-4. When there is too much condensate, the first vent 5-7 is opened. The condensate enters the gas generator 3 through the first vent 5-7 and the condensate inlet 3-2 to generate gas again.

[0053] The fully vaporized mixed air gas undergoes secondary filtration through the filter device 5-3. At this point, the pure mixed air gas enters the gas transmission pipeline through the third mixed air outlet 5-2. Due to the low ambient temperature or the excessive length of the transmission pipeline, the mixed air gas may also experience condensation within the gas pipeline. Therefore, one or more heating tanks 6 need to be installed in the transmission pipeline to maintain the vaporization state. The condensate in the pipeline enters the heating tank 6 through the third mixed air inlet 6-1. The operation of the third hot water coil 6-5 is determined by observing the second temperature acquisition port 6-3 and the fourth liquid level gauge 6-4. When there is a large amount of liquid in the heating tank and the temperature is lower than the set value, the third hot water coil 6-5 heats up to promote the vaporization of the mixed air gas until the mixed air gas is delivered to the gas consumption end.

[0054] It should be reiterated that the purpose of this utility model is only to provide the hardware foundation of a low-temperature light hydrocarbon gas conveying device, and does not involve the electrical control system and related software. This utility model has provided a detailed description and demonstration of the hardware structure of the device. Those skilled in the art can fully realize the purpose of this utility model based on the contents of this utility model specification, that is, to make the hardware foundation of a low-temperature light hydrocarbon gas conveying device.

[0055] The fourth mixed air outlet 6-2 of this utility model can be connected to the inlet of the light hydrocarbon dual backup pressure reducing pipeline of the light hydrocarbon gas low-pressure conveying device via a pipeline.

[0056] The light hydrocarbon gas low-pressure transmission unit includes a three-stage natural gas pressure reducing pipeline, a dual-fuel switching section, and a light hydrocarbon dual-backup pressure reducing pipeline. The outlet of the natural gas pressure reducing pipeline is connected to the natural gas inlet of the dual-fuel switching section, and the outlet of the light hydrocarbon dual-backup pressure reducing pipeline is connected to the light hydrocarbon inlet of the dual-fuel switching section.

[0057] This utility model discloses a low-pressure light hydrocarbon fuel transmission device, providing an improved solution for adding light hydrocarbon fuel to traditional gas pipelines. The gas-consuming end can choose between natural gas or light hydrocarbons for energy supply, ensuring a stable gas source. Furthermore, the use of light hydrocarbon energy can reduce energy costs and increase safety.

[0058] This utility model provides a method for modifying a natural gas pipeline by adding backup light hydrocarbon gas pipelines, which adds two backup light hydrocarbon gas pipelines without changing the original natural gas supply pipeline.

[0059] This utility model provides a dual-backup pressure-reducing pipeline for light hydrocarbons, offering a redundant structure. If one pipeline fails, it can be switched to the other to ensure stable operation.

[0060] The natural gas pressure reducing pipeline includes a natural gas filter 10-1. The inlet of the natural gas filter 10-1 is a natural gas input port. The outlet of the natural gas filter 10-1 is connected to the inlet of the first-stage pressure reducing pipeline. The outlet of the first-stage pressure reducing pipeline is connected to the inlet of the second-stage pressure reducing pipeline. The outlet of the second-stage pressure reducing pipeline is connected to the inlet of the third-stage pressure reducing pipeline. The outlet of the third-stage pressure reducing pipeline is connected to the natural gas inlet of the dual-fuel switching section.

[0061] The first-stage pressure reducing pipeline, the second-stage pressure reducing pipeline, and the third-stage pressure reducing pipeline include, in series, a shut-off valve 10-2, a natural gas pressure reducing valve 10-3, a natural gas pipeline pressure gauge 10-4, a natural gas pipeline overpressure relief valve 10-5, a butterfly valve 10-6, and a check valve 10-7.

[0062] The natural gas three-stage pressure reducing pipeline begins with the main natural gas line passing through natural gas filter 10-1 into the pressure reducing system. The natural gas pipeline pressure is initially at a sub-high pressure (Class B) delivery pressure of 0.4-0.8 MPa. After passing through the first-stage pressure reducing pipeline, it is reduced to a medium pressure (Class A) delivery pressure of 0.20-0.4 MPa. The first-stage pressure reducing pipeline consists of: shut-off valve 10-2; natural gas pressure reducing valve 10-3; natural gas pipeline pressure gauge 10-4; natural gas pipeline overpressure relief valve 10-5; butterfly valve 10-6; and check valve 10-7. The pressure is then reduced from Class A to Class B (0.010-0.2 MPa) for the second stage of pressure reduction, requiring another passage through shut-off valve 10-2, natural gas pressure reducing valve 10-3, natural gas pipeline pressure gauge 10-4, natural gas pipeline overpressure relief valve 10-5, butterfly valve 10-6, and check valve 10-7. The pressure reduction from medium pressure B to below low pressure 0.01MPa is the third stage of pressure reduction. It needs to pass through pipeline shut-off valve 10-2, natural gas pressure reducing valve 10-3, natural gas pipeline pressure gauge 10-4, natural gas pipeline overpressure relief valve 10-5, butterfly valve 10-6, check valve 10-7 and finally enter one end of the natural gas and light hydrocarbon dual fuel switching pipeline.

[0063] The dual-fuel switching section includes a three-way switching valve 20-4, a dual-fuel pipeline check valve 20-3, a dual-fuel pipeline shut-off valve 20-2, and a dual-fuel pipeline pressure gauge 20-1. The first port of the three-way switching valve 20-4 is the natural gas inlet, the second port of the three-way switching valve 20-4 is the light hydrocarbon inlet, and the third port of the three-way switching valve 20-4 is connected to the user end in sequence through the dual-fuel pipeline check valve 20-3, the dual-fuel pipeline shut-off valve 20-2, and the dual-fuel pipeline pressure gauge 20-1.

[0064] The gas sources for the natural gas and dual-fuel switching section are reduced to low-pressure natural gas and light hydrocarbon gas, respectively. After passing through the dual-fuel pipeline check valve 20-3, the dual-fuel pipeline shut-off valve 20-2, and the dual-fuel pipeline pressure gauge 20-1, they enter the user end.

[0065] The adoption of a three-way switching valve 20-4 makes the switching operation between natural gas and light hydrocarbons simpler and safer.

[0066] The light hydrocarbon dual-backup pressure reducing pipeline includes a light hydrocarbon filter. The inlet of the light hydrocarbon filter is the light hydrocarbon input port. The outlet of the light hydrocarbon filter is connected to the inlet of the first light hydrocarbon backup pipeline and the inlet of the second light hydrocarbon backup pipeline via a first tee. The light hydrocarbon inlet of the dual-fuel switching section is connected to the outlet of the first light hydrocarbon backup pipeline and the outlet of the second light hydrocarbon backup pipeline via a second tee.

[0067] The light hydrocarbon dual-backup pressure reducing pipeline has two paths after the light hydrocarbon gas source passes through the light hydrocarbon filter. The two light hydrocarbon gas paths pass through the shut-off valve 30-1, light hydrocarbon pressure reducing valve 30-2, light hydrocarbon pressure regulating valve 30-3, pressure gauge overpressure relief valve 30-5, and shut-off valve 30-6 on the two pipelines respectively, and then converge at the other end of the natural gas and light hydrocarbon dual-fuel switching pipeline.

[0068] The first and second three-way valves are three-way switching valves.

[0069] The first backup pipeline and the second backup pipeline for light hydrocarbons are connected in series from the inlet to the outlet as follows: shut-off valve 30-1, light hydrocarbon pressure reducing valve 30-2, pressure gauge 30-3, light hydrocarbon pressure regulating valve 30-4, butterfly valve 30-5, and check valve 30-6.

[0070] like Figure 8As shown, this case presents two energy supply methods. The first method uses natural gas. The natural gas main pipeline enters the natural gas filter 10-1, which filters out condensate and fine particles entrained in the natural gas. This is the first stage of pressure reduction. The shut-off valve 10-2 and butterfly valve 10-6 are opened, allowing the natural gas to enter the pressure-reducing pipeline. First, the pressure is reduced from sub-high pressure (Level B) to medium pressure (Level A) by the natural gas pressure-reducing valve 10-3. The pressure gauge 10-4 is then monitored to ensure it remains within safe limits. If the pressure exceeds the preset limit, the overpressure relief valve 10-6 is opened to reduce the downstream pipeline pressure. The second and third stages of pressure reduction operate on the same principle as the first. Through the three-stage pressure-reducing device, the natural gas pipeline pressure is reduced to a low pressure. Finally, the user opens the dual-fuel pipeline shut-off valve 20-2, and the natural gas passes through the dual-fuel pipeline check valve 20-3 and the dual-fuel pipeline pressure gauge 20-1 before entering the user's end.

[0071] The second type of light hydrocarbon gas supply involves a main light hydrocarbon gas pipeline that enters a light hydrocarbon filter to remove condensate and fine particles. The gas is then split into two identical pipelines. One pipeline's shut-off valve 30-1 and butterfly valve 30-5 are opened, allowing the light hydrocarbon gas to enter a light hydrocarbon pressure reducing valve 30-2 for pressure reduction. It then enters a light hydrocarbon pressure regulating valve 30-4, where the pressure is adjusted to meet the transmission requirements (pressurization is required during light hydrocarbon gas transmission, but the pressure cannot be too high, as this can cause liquefaction). Finally, the user opens the dual-fuel pipeline shut-off valve 20-2, and the natural gas passes through the dual-fuel pipeline check valve 20-3 and the dual-fuel pipeline pressure gauge 20-1 before entering the user's end.

[0072] Light hydrocarbons have a high calorific value and are inexpensive, so it is the preferred method to connect the light hydrocarbon pipeline to the user end, which is controlled by a three-way switching valve 20-4. When the ambient temperature is low (e.g., the outdoor temperature is below -20°C) or the supply of light hydrocarbons is insufficient, it can be switched to the natural gas pipeline.

[0073] It should be reiterated that the purpose of this utility model is only to provide the hardware basics of a low-pressure light hydrocarbon gas transmission device, and does not involve the electrical control system and related software. This utility model has provided a detailed description and demonstration of the hardware structure of the device. Those skilled in the art can fully realize the purpose of this utility model, namely, to make the hardware basics of a low-pressure light hydrocarbon gas transmission device, based on the contents of this utility model specification.

[0074] It is understood that the above specific description of this utility model is only used to illustrate this utility model and is not limited to the technical solutions described in the embodiments of this utility model. Those skilled in the art should understand that modifications or equivalent substitutions can still be made to this utility model to achieve the same technical effect; as long as the use needs are met, they are all within the protection scope of this utility model.

Claims

1. A low-temperature light hydrocarbon fuel gas conveying device, comprising a raw material tank (1), an air tank (2), a gas generator (3), a buffer tank (4), and a reflux tank (5), characterized in that... The raw material outlet (1-5) of the raw material tank (1) is connected to the raw material inlet (3-6) of the gas generator (3), the air inlet (3-3) of the gas generator (3) is connected to the air outlet (2-4) of the air tank (2), the condensate inlet (3-2) of the gas generator (3) is connected to the first vent (5-7) of the reflux tank (5), the first mixed air outlet (3-1) of the gas generator (3) is connected to the first mixed air inlet (4-2) of the buffer tank (4), the filtrate inlet (3-5) of the gas generator (3) is connected to the second vent (4-6) of the buffer tank (4), and the second mixed air outlet (4-4) of the buffer tank (4) is connected to the second mixed air inlet (5-1) of the reflux tank (5).

2. The low-temperature light hydrocarbon gas conveying equipment according to claim 1, characterized in that... It also includes a heating tank (6), whose third mixing inlet (6-1) is connected to the third mixing outlet (5-2) of the reflux tank (5).

3. The low-temperature light hydrocarbon gas conveying equipment according to claim 1, characterized in that... The raw material tank (1) is provided with a raw material tank opening (1-1), a first air inlet (1-2), a level gauge connection port, a pressure gauge connection port, a third vent (1-4), and a raw material outlet (1-5). The first air inlet (1-2) is connected to a nitrogen tank, the level gauge connection port is connected to a first level gauge (1-3), and the pressure gauge connection port is connected to a first pressure gauge (1-6).

4. The low-temperature light hydrocarbon gas conveying device according to claim 1, characterized in that... The air tank (2) is provided with a pressure relief port, a second air inlet (2-2), a pressure gauge interface, an air outlet (2-4) and a fourth vent (2-6). The pressure relief port is connected to a pressure relief valve (2-1), the pressure gauge interface is connected to a second pressure gauge (2-3), and the second air inlet (2-2) is connected to an air compressor.

5. The low-temperature light hydrocarbon gas conveying equipment according to claim 1, characterized in that... The gas generator (3) is provided with a first mixed air outlet (3-1), a condensate inlet (3-2), an air inlet (3-3), a filtrate inlet (3-5), a raw material inlet (3-6), a level gauge interface, and a fifth vent (3-9). The lower part of the gas generator (3) is equipped with a first hot water coil (3-7), and the level gauge interface is connected to the second level gauge (3-8). A condensate inlet (3-2) is connected to a condensate riser, and the lower end of the condensate riser is placed in the middle of the gas generator (3); A flap (3-4) is provided in the middle of the gas generator (3). The inner end of the flap (3-4) is fixedly connected to the upper end of the downward extending connecting rod and hinged to the lower outer wall of the condensate vertical pipe. The lower end of the connecting rod is connected to the float (3-10). Air inlet (3-3) is connected to air outlet (2-4); raw material inlet (3-6) is connected to raw material outlet (1-5); first mixed air outlet (3-1) is connected to first mixed air inlet (4-2); filtrate inlet (3-5) is connected to second vent (4-6); condensate inlet (3-2) is connected to first vent (5-7).

6. The low-temperature light hydrocarbon gas conveying device according to claim 1, characterized in that... The buffer tank (4) is provided with a first mixing air inlet (4-2), a second mixing air outlet (4-4), and a second vent (4-6). The second vent (4-6) is located at the lower end of the buffer tank (4). The first mixing air inlet (4-2) is located on the upper part of one side of the buffer tank (4). The second mixing air outlet (4-4) is located on the upper part of the other side of the buffer tank (4) below the first mixing air inlet (4-2). The second mixing air outlet (4-4) is connected to the gas filter (4-3) through the outlet L-shaped pipe inside the buffer tank (4). The first mixing air inlet (4-2) is connected to the upper end of the inlet L-shaped pipe, and the lower end of the inlet L-shaped pipe is placed in the lower part of the buffer tank (4). The buffer tank (4) is provided with a cross baffle (4-5) in the middle. The cross baffle (4-5) includes multiple inclined baffles that are symmetrically arranged on both sides and tilted from top to bottom. The inclined baffles on the same side are parallel to each other and have equal spacing. An opening is provided on one side of the inclined baffle, the openings of the inclined baffles on the same side are located on the same side, and the openings of the inclined baffles on both sides are located on opposite sides.

7. The low-temperature light hydrocarbon gas conveying equipment according to claim 1, characterized in that... The reflux tank (5) is provided with a second mixed air inlet (5-1), a third mixed air outlet (5-2), a level gauge interface, a first temperature acquisition port (5-5), and a first vent (5-7). The second mixed air inlet (5-1) is located at the upper end of the reflux tank (5), the third mixed air outlet (5-2) is located at the upper right side of the reflux tank (5), the level gauge interface is located at the lower right side of the reflux tank (5), the first temperature acquisition port (5-5) is located at the lower left side of the reflux tank (5), and the first vent (5-7) is located at the end of the reflux tank (5). A filter device (5-3) is provided in the middle of the reflux tank (5), a second hot water coil (5-6) is provided in the lower part of the reflux tank (5), and the level gauge interface is connected to the third level gauge (5-4).

8. The low-temperature light hydrocarbon gas conveying equipment according to claim 2, characterized in that... The heating tank (6) is provided with a third mixing air inlet (6-1), a fourth mixing air outlet (6-2), a second temperature acquisition port (6-3), a level gauge interface and a sixth vent (6-6). The third mixing air inlet (6-1) and the fourth mixing air outlet (6-2) are located at the upper end of the heating tank (6). A mixing air inlet pipe is connected to the third mixing air inlet (6-1). The lower end of the mixing air inlet pipe is located in the middle of the heating tank (6). The second temperature acquisition port (6-3) is located in the lower left part of the heating tank (6). The level gauge interface is located in the lower right part of the heating tank (6). The sixth vent (6-6) is located at the lower end of the heating tank (6). The level gauge interface is connected to the fourth level gauge (6-4). A third hot water coil (6-5) is provided in the lower part of the heating tank (6).

9. The low-temperature light hydrocarbon gas conveying device according to claim 8, characterized in that... The fourth mixed air outlet (6-2) is connected to the inlet of the light hydrocarbon dual-backup pressure reducing pipeline of the light hydrocarbon low-pressure gas transmission device via a pipeline; the light hydrocarbon low-pressure gas transmission device includes a natural gas three-stage pressure reducing pipeline, a dual-fuel switching section and a light hydrocarbon dual-backup pressure reducing pipeline, the outlet of the natural gas pressure reducing pipeline is connected to the natural gas inlet of the dual-fuel switching section, and the outlet of the light hydrocarbon dual-backup pressure reducing pipeline is connected to the light hydrocarbon inlet of the dual-fuel switching section.

10. The low-temperature light hydrocarbon gas conveying device according to claim 9, characterized in that... The light hydrocarbon dual-backup pressure reducing pipeline includes a light hydrocarbon filter. The inlet of the light hydrocarbon filter is the light hydrocarbon input port. The outlet of the light hydrocarbon filter is connected to the inlet of the first light hydrocarbon backup pipeline and the inlet of the second light hydrocarbon backup pipeline via a first tee. The light hydrocarbon inlet of the dual-fuel switching section is connected to the outlet of the first light hydrocarbon backup pipeline and the outlet of the second light hydrocarbon backup pipeline via a second tee.

Images