A skid-mounted drying device and combustion system for associated gas combustion in oil well casing

Abstract

This utility model discloses a skid-mounted drying device and combustion system for associated gas combustion in oil well casing. The drying device includes an associated gas drying unit and a natural gas drying unit. The associated gas drying unit is connected to a vortex tube. The natural gas drying unit includes a natural gas pipeline and a cryogenic gas pipeline. The cold end of the vortex tube is connected to the cryogenic gas pipeline, which cools the natural gas pipeline, causing water vapor to condense inside the natural gas pipeline. The natural gas pipeline is connected to a drainage unit. This utility model generates cold air by rapidly injecting compressed air and oil well casing gas into the vortex tube, thereby cooling and dehydrating the natural gas. This more effectively removes moisture and hydrocarbons from the natural gas, resulting in more thorough dehydration and hydrocarbon removal, and solving the problem of incomplete drying in existing technologies.

Description

Technical Field

[0001] This utility model relates to the field of gas drying technology, specifically to a skid-mounted drying device and combustion system for associated gas combustion in oil well casing. Background Technology

[0002] Currently, most oilfields utilize associated gas from oil wells to supply combustion gas for heating furnaces. This associated gas contains a certain amount of water vapor and hydrocarbons. These condensable vapors and hydrocarbons readily form liquid water, solid ice, or hydrates during natural gas transportation, severely impacting the service life of associated natural gas transportation and pipelines. Therefore, they need to be recovered. Otherwise, during pipeline gas supply, water vapor and some hydrocarbons will condense when encountering temperatures below their ambient dew point, increasing resistance and even freezing and clogging pipelines, stopping gas supply and heating. Furthermore, the presence of water vapor and hydrocarbons in the associated gas makes the combustion of natural gas in the heating furnace unstable, resulting in low thermal efficiency and substandard flue gas emissions. Therefore, it is necessary to separate water vapor and hydrocarbons from the natural gas. Currently, the methods used for dehydration and dehydrocarbonization of associated gas from oil wells are: first, cyclone separators, which use centrifugal force to separate liquid and gas; however, due to limitations in pressure and flow rate, this method results in incomplete separation of water vapor and hydrocarbons; second, coil-type condenser dryers, which rely on ambient temperature for cooling and separation. Sometimes, the ambient temperature is quite high, leading to incomplete separation of water vapor and hydrocarbons as well. Therefore, removing these condensable vapors and hydrocarbons from associated natural gas is a crucial step.

[0003] This patent improves the separation of water vapor and hydrocarbons by using vortex tubes. Those skilled in the art have proposed the following methods for utilizing vortex tubes.

[0004] Announcement No. CN110762946B discloses a skid-mounted natural gas processing unit, including a cryogenic separator. The gaseous hot phase (approximately -19°C) separated by the cryogenic separator is cooled by a second heat exchanger, and then part of it enters a primary liquid separator tank through a manifold, while the other part enters a feed buffer tank. The liquid phase (-51°C) separated by the cryogenic separator is discharged and then heat-exchanged to -30°C through a refrigerant channel of a condensate cooler, before entering a distillation column used in conjunction with the reboiler. After gas-liquid separation, the gaseous C1 and C2 enter the primary liquid separator tank through a manifold, and the liquid phase is heated to 25°C by heat exchange with the natural gas flowing through the reboiler. The liquid phase C3, C4, and C5+ enter a mixed hydrocarbon storage tank along pipelines.

[0005] The prior art cryogenic separator, namely the vortex tube, is used to separate the components of associated gas, and the prior art uses the vortex tube in a completely different way than this patent.

[0006] Announcement No. CN107965667B discloses a pipeline natural gas pressure regulating system that utilizes the pipeline's own pressure to achieve low-temperature air heat extraction, including an incoming flow PNG, an ejector, an air-temperature heat exchanger, a vortex tube, and a pressure regulating device.

[0007] The prior art uses vortex tubes and air-temperature heat exchangers to heat the incoming PNG flow, and the way the prior art uses vortex tubes is completely different from that of this patent.

[0008] Publication No. CN107715812A discloses a gas hydrate generating apparatus, comprising: a reaction chamber configured to generate gas hydrate therein; a water inlet channel connected to the reaction chamber to supply water required for generating gas hydrate into the reaction chamber; and a heating mechanism, the heating mechanism being at least disposed at the connection between the reaction chamber and the water inlet channel to heat the connection.

[0009] The prior art uses vortex tubes to form hydrate formation zones and hydrate non-formation zones, and the way the prior art uses vortex tubes is completely different from that of this patent.

[0010] In summary, the technical solutions, technical problems to be solved, and beneficial effects of the above-disclosed technologies are all different from those of this utility model. For more technical features, technical problems to be solved, and beneficial effects of this utility model, the above-disclosed technical documents do not provide any technical inspiration. Utility Model Content

[0011] In order to overcome the shortcomings of the prior art and solve at least one of the technical problems mentioned in the background art, this utility model provides a skid-mounted drying device and combustion system for associated gas combustion in oil well casing.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] On one hand, this utility model provides a skid-mounted drying device for associated gas combustion in oil well casing, including an associated gas drying unit and a natural gas drying unit; the associated gas drying unit is connected to a vortex tube; the natural gas drying unit includes a natural gas pipeline and a cryogenic gas pipeline; the cold end of the vortex tube is connected to the cryogenic gas pipeline, and the cryogenic gas pipeline cools the natural gas pipeline, causing water vapor to condense inside the natural gas pipeline; the natural gas pipeline is connected to a drainage unit.

[0014] Furthermore, the natural gas drying unit also includes a heat exchanger;

[0015] Specifically, the heat exchanger shell is a low-temperature gas pipeline, and a natural gas pipeline is installed inside the heat exchanger;

[0016] Specifically, the two ends of the natural gas pipeline are connected to the inlet valve of the external natural gas supply to the heat exchanger and the outlet check valve of the heat exchanger;

[0017] Specifically, the heat exchanger outlet check valve is connected to the heat exchanger outlet control valve, and the heat exchanger outlet control valve is connected to the drainage unit.

[0018] Specifically, the heat exchanger shell is connected to a low-temperature gas inlet heat exchanger valve, a low-temperature gas outlet heat exchanger valve, and a heat exchanger temperature and pressure transmitter. The low-temperature gas inlet heat exchanger valve is connected to the cold end of the vortex tube.

[0019] Furthermore, the drainage unit includes a submersible air chamber;

[0020] Specifically, the submersible gas manifold is connected to the heat exchanger outlet control valve, the lower end of the submersible gas manifold is connected to the submersible gas manifold vent pipeline, the submersible gas manifold vent pipeline is equipped with a submersible gas manifold vent valve, the submersible gas manifold is connected to the submersible gas manifold temperature and pressure transmitter, the submersible gas manifold is connected to the submersible gas manifold outlet valve, and the submersible gas manifold outlet valve is used to connect to the gas pipeline of the heating furnace.

[0021] Furthermore, it also includes air bags;

[0022] Specifically, the gas manifold is connected to the inlet valve, the inlet valve is connected to the hot end of the vortex tube, and the inlet valve is connected to the low-temperature gas outlet heat exchanger valve through the low-temperature gas recovery pipeline.

[0023] Specifically, the gas reservoir is connected to the gas reservoir valve, and the gas reservoir valve is connected between the heat exchanger outlet check valve and the heat exchanger outlet control valve via a hot gas utilization pipeline.

[0024] Specifically, the air tank is connected to a pressure gauge, the air tank is connected to an inlet valve, the inlet valve is connected to an inlet check valve, and the inlet valve is used to connect to the main pipeline process.

[0025] Furthermore, the air inlet of the vortex tube is connected to the main air inlet valve, and the main air inlet valve is connected to the associated gas drying unit;

[0026] Specifically, the cold end of the vortex tube is connected to the low-temperature end control valve, the low-temperature end control valve is connected to the low-temperature gas inlet heat exchanger valve, and a low-temperature end temperature and pressure transmitter is connected between the cold end of the vortex tube and the low-temperature end control valve.

[0027] Specifically, the hot end of the vortex tube is connected to a high-temperature end control valve, the high-temperature end control valve is connected to an air inlet valve, and a high-temperature end temperature and pressure transmitter is connected between the hot end of the vortex tube and the high-temperature end control valve.

[0028] Furthermore, a high-temperature gas venting pipeline is provided between the high-temperature end control valve and the air inlet valve, and a high-temperature gas venting valve is provided on the high-temperature gas venting pipeline;

[0029] Specifically, the heat exchanger shell is connected to a low-temperature gas venting unit;

[0030] Specifically, the low-temperature gas venting unit includes a heat exchanger venting pipeline;

[0031] Specifically, the heat exchanger vent line is connected to the bottom of the heat exchanger shell, and the heat exchanger vent line is connected in parallel to a low-temperature gas vent valve and a low-temperature gas supply valve; the low-temperature gas supply valve is used to supply low-temperature gas to other equipment.

[0032] Furthermore, the associated gas drying unit includes a condenser dryer;

[0033] Specifically, the condenser dryer is connected to a pressure regulating unit via a connecting pipe, the pressure regulating unit is connected to the main air inlet valve, and the air inlet of the pressure regulating unit is connected to the associated gas drying unit and the compressed air input unit, respectively.

[0034] Furthermore, the pressure regulating unit includes a pressure regulating pipeline and a bypass pipeline. An inlet valve and a outlet valve are sequentially arranged on the pressure regulating pipeline. An automatic pressure regulating valve and a pressure regulating gauge are arranged between the inlet valve and the outlet valve. A bypass valve is arranged on the bypass pipeline. The two ends of the bypass pipeline are respectively connected to the two ends of the pressure regulating pipeline.

[0035] Specifically, the compressed air input unit includes an air filter, an air compressor, and an air compressor outlet valve connected in sequence. The air compressor outlet is connected to a pressure gauge, and the outlet valve is connected to the air inlet of the pressure regulating unit.

[0036] Furthermore, the associated gas drying unit, natural gas drying unit, vortex tube, drainage unit, low-temperature gas venting unit, pressure regulating unit, and gas manifold are all mounted on a skid-mounted chassis.

[0037] Secondly, this utility model provides an associated gas combustion system for oil well casing, including a wellhead, a heating furnace, and an external natural gas pipeline. The wellhead is equipped with a casing gas valve, and the system also includes a skid-mounted drying device for associated gas combustion in oil well casing as described in one aspect. The casing gas valve is connected to the associated gas drying unit; the natural gas pipeline is connected to the natural gas drying unit; and the hot end of the vortex tube, the outlet of the natural gas pipeline, and the low-temperature gas pipeline are connected to the inlet of the heating furnace.

[0038] Compared with the prior art, the present invention has the following advantages:

[0039] 1. This invention generates cold air by rapidly injecting compressed air and casing gas from the vortex tube, which is then used to cool and dehydrate the natural gas. This method more effectively removes moisture and hydrocarbons from the natural gas, resulting in more thorough dehydration and hydrocarbon removal, thus solving the problem of incomplete drying in existing technologies. This invention removes large amounts of moisture and hydrocarbons from natural gas using an energy-efficient vortex tube and heat exchanger, ensuring stable combustion, improving thermal efficiency, and guaranteeing that flue gas emissions meet standards. It is suitable for portable natural gas drying devices in low-humidity, intermittent environments. Through multi-process coupling, anti-pollution design, and energy self-sufficiency, this invention better adapts to complex operating conditions such as high loads, high humidity, and diverse impurities in associated gas from oil wells.

[0040] 2. The various units of this utility model cooperate with each other to achieve the drying treatment of associated gas in oil well casing and external wet natural gas, as well as the rational utilization of heat. It can not only dehydrate and dehydrocarbonize natural gas, but also use the treated natural gas for combustion in a heating furnace. Through the design of hot gas utilization pipelines, energy self-sufficiency and heat recovery are achieved. This multi-functional integrated design enables the device to meet drying requirements while improving energy utilization efficiency and reducing dependence on external energy.

[0041] 3. This utility model has low manufacturing cost, long service life, energy saving and emission reduction, and is suitable for use in field oil wells, with good application prospects. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of a skid-mounted drying device and combustion system for associated gas combustion in oil well casing, which is a utility model.

[0043] In the diagram: Wellhead - 1; Production valve - 2; Single well oil pipeline - 3; Gas collection pipeline - 4; Inlet dryer check valve - 5; Inlet dryer valve - 6; Pressure gauge - 7; Gas manifold - 8; Inlet gas manifold valve - 9; Outlet gas manifold valve - 10; Casing gas valve - 11; Casing pressure gauge - 12; Condensing dryer - 13; Connecting gas pipe - 14; Inlet gas valve - 15; Automatic pressure regulating valve - 16; Pressure regulator - 17; Outlet gas valve - 18; Main inlet valve -19; Bypass valve -20; Vortex tube -21; High-temperature end temperature and pressure transmitter -22; High-temperature end control valve -23; Low-temperature end temperature and pressure transmitter -24; Low-temperature end control valve -25; Low-temperature gas inlet heat exchanger valve -26; External natural gas inlet heat exchanger valve -27; External natural gas pipeline -28; External natural gas control valve -29; Gas source pressure gauge -30; Gas source pipeline -31; Air filter -32; Air compressor -33; Air compressor outlet valve -34; Pressure gauge -35; Heat exchanger -36; Heat exchanger temperature and pressure transmitter -37; Low-temperature gas outlet valve for heat exchanger -38; Low-temperature gas recovery pipeline -39; Heat exchanger outlet check valve -40; Heat exchanger outlet control valve -41; Submersible gas manifold temperature and pressure transmitter -42; Submersible gas manifold -43; Submersible gas manifold outlet valve -44; Gas pipeline -45; Heating furnace control valve -46; Burner -47; Heating furnace -48; Heating furnace chimney -49; Hot gas utilization pipeline -50; Submersible gas manifold vent valve -51; Submersible gas manifold vent pipeline -52; Heat exchanger vent pipeline -53; Low temperature gas vent valve -54; Low temperature gas supply valve -55; Low temperature gas supply pipeline -56; Control valve for inlet control box -57; Control box -58; High temperature gas vent valve -59; High temperature gas vent pipeline -60; Skid-mounted chassis -61. Detailed Implementation

[0044] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0045] Example 1:

[0046] like Figure 1 As shown, an associated gas combustion skid-mounted drying device for oil well casing includes an associated gas drying unit and a natural gas drying unit. The associated gas drying unit is connected to a vortex tube 21. The natural gas drying unit includes a natural gas pipeline and a cryogenic gas pipeline. The cold end of the vortex tube 21 is connected to the cryogenic gas pipeline. The cryogenic gas pipeline cools the natural gas pipeline, causing water vapor to condense inside the natural gas pipeline. The hot end of the vortex tube 21, the natural gas pipeline, and the gas outlet of the cryogenic gas pipeline are used for combustion in a heating furnace 48.

[0047] Furthermore, the natural gas drying unit includes a heat exchanger 36 and a drainage unit. The shell of the heat exchanger 36 is a low-temperature gas pipeline. A natural gas pipeline is installed inside the heat exchanger 36. The two ends of the natural gas pipeline are connected to an external natural gas inlet valve 27 and a heat exchanger outlet check valve 40. The heat exchanger outlet check valve 40 is connected to a heat exchanger outlet control valve 41. The heat exchanger outlet control valve 41 is connected to the drainage unit. The shell of the heat exchanger 36 is connected to a low-temperature gas inlet valve 26, a low-temperature gas outlet valve 38, and a heat exchanger temperature and pressure transmitter 37. The low-temperature gas inlet valve 26 is connected to the cold end of the vortex tube 21.

[0048] Among them, the external natural gas inlet valve 27 is used to connect the external natural gas pipeline 28.

[0049] Specifically, the natural gas pipeline is a horizontal coil to expand the heat exchange area and prevent liquid accumulation. When using multi-layer horizontal coils, a top-inlet and bottom-outlet scheme is adopted to ensure smooth gas flow.

[0050] Specifically, the drainage unit includes a submersible gas manifold 43, which is connected to the heat exchanger outlet control valve 41. The lower end of the submersible gas manifold 43 is connected to a submersible gas manifold vent line 52, which is equipped with a submersible gas manifold vent valve 51. The submersible gas manifold 43 is connected to a submersible gas manifold temperature and pressure transmitter 42, and is connected to a submersible gas manifold outlet valve 44. The submersible gas manifold outlet valve 44 is used to connect to the gas pipeline 45 of the heating furnace 48.

[0051] Furthermore, it also includes a gas reservoir 8, which is connected to an inlet gas reservoir valve 9, which is connected to the hot end of the vortex tube 21. The inlet gas reservoir valve 9 is connected to a low-temperature gas outlet heat exchanger valve 38 via a low-temperature gas recovery pipeline 39. The gas reservoir 8 is connected to an outlet gas reservoir valve 10, which is connected between a heat exchanger outlet check valve 40 and a heat exchanger outlet control valve 41 via a hot gas utilization pipeline 50. The gas reservoir 8 is connected to a pressure gauge 7 and an inlet dry valve 6, which is connected to an inlet dry check valve 5. The heated low-temperature gas is mixed with the high-temperature gas through the low-temperature gas recovery pipeline 39, and then fed into the burner 47 along with the externally supplied natural gas through the hot gas utilization pipeline 50.

[0052] The inlet valve 6 is used to directly introduce the associated gas in the gas tank 8 into the main process and send it to the burner 47 or to the production pipeline.

[0053] Furthermore, the air inlet of the vortex tube 21 is connected to the main air inlet valve 19, the main air inlet valve 19 is connected to the associated gas drying unit, the cold end of the vortex tube 21 is connected to the low-temperature end control valve 25, the low-temperature end control valve 25 is connected to the low-temperature gas inlet heat exchanger valve 26, the low-temperature end temperature and pressure transmitter 24 is connected between the cold end of the vortex tube 21 and the low-temperature end control valve 25, the hot end of the vortex tube 21 is connected to the high-temperature end control valve 23, the high-temperature end control valve 23 is connected to the air inlet valve 9, and the high-temperature end temperature and pressure transmitter 22 is connected between the hot end of the vortex tube 21 and the high-temperature end control valve 23.

[0054] Specifically, a high-temperature gas venting pipeline 60 is provided between the high-temperature end control valve 23 and the air inlet valve 9, and a high-temperature gas venting valve 59 is provided on the high-temperature gas venting pipeline 60 for venting pressure when the pressure is too high.

[0055] Specifically, the heat exchanger 36 shell is connected to a low-temperature gas venting unit, which includes a heat exchanger venting pipeline 53. The heat exchanger venting pipeline 53 is connected to the bottom of the heat exchanger 36 shell, and the heat exchanger venting pipeline 53 is connected in parallel to a low-temperature gas venting valve 54 and a low-temperature gas supply valve 55. The low-temperature gas supply valve 55 is used to connect to the control valve 57 in the control box to supply low-temperature gas to other equipment.

[0056] Furthermore, the associated gas drying unit includes a condenser dryer 13, which is connected to a pressure regulating unit via a connecting gas pipe 14. The pressure regulating unit is connected to the main inlet valve 19, and the inlet end of the pressure regulating unit is connected to both the associated gas drying unit and the compressed air input unit. The pressure regulating unit adjusts the gas pressure entering the condenser dryer 13, thereby adjusting the outlet gas temperature at the hot and cold ends of the condenser dryer 13. The compressed air input unit supplements the process with high-pressure air, enabling the drying device to operate even when the associated gas pressure is low.

[0057] Among them, the condenser dryer 13 is existing technology, which causes water vapor to condense by lowering the gas temperature below the dew point and drains water periodically during use.

[0058] Specifically, the pressure regulating unit includes a pressure regulating pipeline and a bypass pipeline. An inlet valve 15 and a outlet valve 18 are sequentially arranged on the pressure regulating pipeline. An automatic pressure regulating valve 16 and a pressure regulating gauge 17 are arranged between the inlet valve 15 and the outlet valve 18. A bypass valve 20 is provided on the bypass pipeline. The two ends of the bypass pipeline are respectively connected to the two ends of the pressure regulating pipeline.

[0059] Specifically, the compressed air input unit includes an air filter 32, an air compressor 33, and an air compressor outlet valve 34 connected in sequence. The outlet end of the air compressor 33 is connected to a pressure gauge 35, and the outlet valve 34 is connected to the inlet end of the pressure regulating unit.

[0060] Specifically, the bypass valve 20, the inlet valve 15, the condenser dryer 13, and the air compressor outlet valve 34 are connected by one four-way valve or two three-way valves.

[0061] Furthermore, the associated gas drying unit, natural gas drying unit, vortex tube, drainage unit, cryogenic gas venting unit, pressure regulating unit, and gas manifold 8 are all mounted on the skid-mounted chassis 61; modular assembly and skid-mounted structure, with key components mounted on the skid-mounted chassis, make the device easy to transport and install, especially suitable for complex application scenarios such as field oil wells. In addition, the skid-mounted structure has good sealing performance, which can effectively prevent natural gas leakage and improve the safety of the device. At the same time, the modular design also facilitates the maintenance and repair of each component, reducing maintenance costs and safety risks.

[0062] The working principle is as follows:

[0063] The vortex tube 21 is a device that can separate gas into two streams, one hot and one cold. Well casing gas or compressed air is introduced into the inlet of the vortex tube 21, and after passing through the nozzle of the vortex tube 21, it is tangentially transformed into a swirling flow. Two streams of gas with opposite flow directions are formed inside the vortex tube. The inner gas has a lower temperature and flows out from the cold port, while the outer gas has a higher temperature and flows out from the hot port. When compressed air at a certain pressure is input, it is converted by the vortex tube, producing cold air at one end (the minimum temperature can reach 46°C under the premise of dry air) and hot air at the other end (the maximum temperature can reach 127°C). The cold air is used to condense and dry the combustion gas. In this embodiment, the vortex tube 21 and the heat exchanger 36 are used for moisture dehydration.

[0064] This embodiment provides a natural gas drying device consisting of a simple structure, an energy-free vortex tube 21, and a heat exchanger. The device has a simple structure, stable performance, low cost, long service life, no additional energy consumption, and is environmentally friendly and energy-saving. It is suitable for field use and has good application prospects.

[0065] It should be noted that the pipe fittings and valves in this embodiment are all connected by sealed pipe threads, the valves in this embodiment are all solenoid valves, and the pressure gauges and temperature gauges in this embodiment are all electronic gauges, which are convenient for electric control.

[0066] Example 2:

[0067] Based on Example 1, this example provides an associated gas combustion system for oil well casing, including a wellhead 1, a heating furnace 48, and the drying device described in Example 1.

[0068] The wellhead 1 is equipped with a production valve 2 and a casing gas valve 11. The production valve 2 is connected to the single-well oil pipeline 3. The single-well oil pipeline 3 is connected to the external transmission trunk line. The inlet trunk line single-flow valve 5 is connected to the single-well oil pipeline 3 through the gas receiving pipeline. The single-well oil pipeline 3 is provided with a branch line connected to the heating pipe of the heating furnace 48. After heating, the oil is transmitted externally. The casing gas valve 11 is connected to the condenser dryer 13. The casing gas valve 11 is connected to the casing pressure gauge 12.

[0069] The external natural gas inlet valve 27 is connected to the external natural gas pipeline 28, the external natural gas pipeline 28 is connected to the gas source pipeline 31, and the external natural gas pipeline 28 is equipped with an external natural gas control valve 29 and a gas source pressure gauge 30.

[0070] The submersible gas manifold outlet valve 44 is connected to the gas pipeline 45, the gas pipeline 45 is connected to the heating furnace control valve 46, the heating furnace control valve 46 is connected to the burner 47 of the heating furnace 48, and the heating furnace 48 is equipped with a heating furnace chimney 49.

[0071] The low-temperature gas supply valve 55 is connected to the low-temperature gas supply pipeline 56. The low-temperature gas supply pipeline 56 is equipped with a control valve 57 for the control box. The low-temperature gas supply pipeline 56 is connected to the control box 58. When the natural gas is dried entirely with air, low-temperature air can be output to the control box 58 through the low-temperature gas supply pipeline 56 for cooling.

[0072] Example 3:

[0073] Based on Example 2, this example provides an operation method for an associated gas combustion system in an oil well casing:

[0074] Drying of wet natural gas in oil well casing:

[0075] The wet associated gas in oil well 1 enters the condenser dryer 13 through the wet associated gas valve 11 to achieve primary drying, and then enters the vortex pipe 21 in sequence through the connecting gas pipe 14, the inlet gas valve 15, the automatic pressure regulating valve 16, the pressure regulating gauge 17, the rear outlet gas valve 18, and the main inlet gas valve 19.

[0076] The cold end of the vortex tube 21 outputs low-temperature gas to the low-temperature end control valve 25. The low-temperature end temperature and pressure transmitter 24 monitors the pressure and temperature of the low-temperature gas. The low-temperature gas enters the heat exchanger 36 through the low-temperature gas inlet heat exchanger valve 26. The heat exchanger temperature and pressure transmitter 37 monitors the pressure and temperature of the low-temperature gas in the heat exchanger 36. After circulating in the heat exchanger 36, the low-temperature gas enters the gas tank 8 through the low-temperature gas outlet heat exchanger valve 38, the low-temperature gas recovery pipeline 39, and the gas tank valve 9.

[0077] The hot end of the vortex tube 21 outputs high-temperature gas to the high-temperature end control valve 23. The high-temperature end temperature and pressure transmitter 22 monitors the pressure and temperature of the high-temperature gas. The high-temperature gas enters the gas chamber 8 through the inlet valve 9.

[0078] The pressure gauge 7 of the gas tank 8 monitors the pressure after the hot and cold gas are mixed; a portion of the associated gas in the gas tank 8 enters the single-well oil pipeline 3 for recovery through the inlet valve 6, the inlet check valve 5, and the gas collection pipeline 4; another portion of the associated gas in the gas tank 8 enters the burner 47 for combustion and heating in the heater 48 through the outlet valve 10, the hot gas utilization pipeline 50, the heat exchanger outlet control valve 41, the submerged gas tank 43, the submerged gas tank outlet valve 44, the gas pipeline 45, and the heater control valve 46; the submerged gas tank temperature and pressure transmitter 42 monitors the pressure and temperature of the supplied gas.

[0079] When the pressure of the wet associated gas in wellhead 1 is low, open the bypass valve 20 and close the inlet valve 15; or start the air compressor 33 to output high-pressure air to the pressure regulating unit.

[0080] Drying of imported wet natural gas:

[0081] Externally supplied wet natural gas flows sequentially through gas source pipeline 31, gas source pressure gauge 30, externally supplied wet natural gas control valve 29, externally supplied natural gas pipeline 28, and externally supplied wet natural gas inlet heat exchanger valve 27 into heat exchanger 36 for heat exchange and cooling. After heat exchange and cooling, it flows through heat exchanger outlet check valve 40, heat exchanger outlet control valve 41, submerged gas manifold 43, submerged gas manifold outlet valve 44, gas pipeline 45, and heater control valve 46 into burner 47 for combustion and heating of heater 48. The generated flue gas is discharged into the atmosphere through heater chimney 49. Heater chimney 49 is equipped with test holes for periodic monitoring of flue gas composition.

[0082] The skid-mounted drying unit for associated gas combustion in oil well casings avoids problems such as substandard combustion flue gas and low thermal efficiency by efficiently drying the combusted natural gas.

[0083] The liquid produced from oil well 1 enters the heating furnace 48 for heating and external discharge via production valve 2 and single-well oil pipeline 3. The heating temperature is adjusted by regulating the gas flow through the heating furnace control valve 46, associated gas valve 11, and automatic pressure regulating valve 16. The generated flue gas is discharged through the heating furnace chimney 49. Whether the flue gas composition meets the standards is controlled by adjusting the pressure and temperature inside the heat exchanger 36 through the main inlet valve 19. To increase the dryness of the externally supplied natural gas, the mixing ratio of the burner 47 is controlled by controlling the opening size of the outlet valve 10 and the externally supplied natural gas inlet heat exchanger valve 27. By adjusting the gas flow, dryness, and mixing ratio, the composition of the flue gas discharged from the heating furnace chimney 49 is ensured to meet the standards.

[0084] Venting and drainage process:

[0085] When the pressure in heat exchanger 36 is too high, the low temperature gas is released into the atmosphere through heat exchanger venting process 53 and low temperature gas venting valve 54.

[0086] When the pressure in air tank 8 is too high, it is released into the atmosphere through air tank valve 9, high temperature gas venting valve 59, and high temperature gas venting pipeline 60.

[0087] The condensate produced by the wet natural gas is discharged by draining the water from the submerged gas tank 43 through the vent valve 51 of the submerged gas tank, and the condenser dryer 13 is drained by opening its own drain valve.

[0088] When the sleeve air valve 11 is closed and only the air compressor 33 generates high-pressure air, the low-temperature air supply valve 55 is opened. The low-temperature air enters the control box 58 through the control box control valve 57 to cool it down, protect the electronic components, and also blow away dust.

[0089] The drying device of this embodiment is a compact gas drying device with a compact structure, easy to move, and good sealing performance. Using this drying device to efficiently dry combusted natural gas can remove a large amount of moisture and hydrocarbons from the natural gas.

[0090] All components not discussed in detail in this application, as well as the connection methods of these components, are well-known technologies in this field. They can be directly applied and will not be elaborated further.

[0091] In this utility model, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0092] In the description of this utility model, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0093] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0094] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A skid-mounted drying device for associated gas combustion in oil well casing, characterized in that, Includes associated gas drying unit and natural gas drying unit; The associated gas drying unit is connected to a vortex tube; The natural gas drying unit includes a natural gas pipeline and a cryogenic gas pipeline; The cold end of the vortex tube is connected to a cryogenic gas pipeline, which cools the natural gas pipeline, causing water vapor to condense inside the natural gas pipeline. The natural gas pipeline is connected to the drainage unit.

2. The skid-mounted drying device for associated gas combustion in oil well casing according to claim 1, characterized in that, The natural gas drying unit also includes a heat exchanger; The heat exchanger shell is a low-temperature gas pipeline, and a natural gas pipeline is installed inside the heat exchanger; The natural gas pipeline is connected at both ends to an external natural gas inlet valve and a heat exchanger outlet check valve. The heat exchanger outlet check valve is connected to the heat exchanger outlet control valve, and the heat exchanger outlet control valve is connected to the drainage unit. The heat exchanger shell is connected to a low-temperature gas inlet heat exchanger valve, a low-temperature gas outlet heat exchanger valve, and a heat exchanger temperature and pressure transmitter. The low-temperature gas inlet heat exchanger valve is connected to the cold end of the vortex tube.

3. The skid-mounted drying device for associated gas combustion in oil well casing according to claim 2, characterized in that, The drainage unit includes a submersible air chamber; The submersible gas manifold is connected to the heat exchanger outlet control valve. The lower end of the submersible gas manifold is connected to the submersible gas manifold vent pipeline. The submersible gas manifold vent pipeline is equipped with a submersible gas manifold vent valve. The submersible gas manifold is connected to a submersible gas manifold temperature and pressure transmitter. The submersible gas manifold is connected to a submersible gas manifold outlet valve. The submersible gas manifold outlet valve is used to connect to the gas pipeline of the heating furnace.

4. The skid-mounted drying device for associated gas combustion in oil well casing according to claim 2, characterized in that, It also includes air bags; The gas manifold is connected to the inlet valve, the inlet valve is connected to the hot end of the vortex tube, and the inlet valve is connected to the low-temperature gas outlet heat exchanger valve through the low-temperature gas recovery pipeline. The gas reservoir is connected to the gas reservoir valve, and the gas reservoir valve is connected between the heat exchanger outlet check valve and the heat exchanger outlet control valve through a hot gas utilization pipeline. The air tank is connected to a pressure gauge, the air tank is connected to an inlet valve, the inlet valve is connected to an inlet check valve, and the inlet valve is used to connect to the main pipeline process.

5. The skid-mounted drying device for associated gas combustion in oil well casing according to claim 4, characterized in that, The air inlet of the vortex tube is connected to the main air inlet valve, and the main air inlet valve is connected to the associated gas drying unit. The cold end of the vortex tube is connected to the low-temperature end control valve, the low-temperature end control valve is connected to the low-temperature gas inlet heat exchanger valve, and a low-temperature end temperature and pressure transmitter is connected between the cold end of the vortex tube and the low-temperature end control valve. The hot end of the vortex tube is connected to the high-temperature end control valve, the high-temperature end control valve is connected to the air inlet valve, and a high-temperature end temperature and pressure transmitter is connected between the hot end of the vortex tube and the high-temperature end control valve.

6. The skid-mounted drying device for associated gas combustion in oil well casing according to claim 5, characterized in that, A high-temperature gas venting pipeline is provided between the high-temperature end control valve and the air inlet valve, and a high-temperature gas venting valve is provided on the high-temperature gas venting pipeline. The heat exchanger shell is connected to a low-temperature gas venting unit; The low-temperature gas venting unit includes a heat exchanger venting pipeline; The heat exchanger vent line is connected to the bottom of the heat exchanger shell, and the heat exchanger vent line is connected in parallel to a low-temperature gas vent valve and a low-temperature gas supply valve; the low-temperature gas supply valve is used to supply low-temperature gas to other equipment.

7. The skid-mounted drying device for associated gas combustion in oil well casing according to claim 6, characterized in that, The associated gas drying unit includes a condenser dryer; The condenser dryer is connected to a pressure regulating unit via a connecting pipe. The pressure regulating unit is connected to the main air inlet valve. The air inlet of the pressure regulating unit is connected to the associated gas drying unit and the compressed air input unit, respectively.

8. The skid-mounted drying device for associated gas combustion in oil well casing according to claim 7, characterized in that, The pressure regulating unit includes a pressure regulating pipeline and a bypass pipeline. An inlet valve and a outlet valve are sequentially arranged on the pressure regulating pipeline. An automatic pressure regulating valve and a pressure regulating gauge are arranged between the inlet valve and the outlet valve. A bypass valve is arranged on the bypass pipeline. Both ends of the bypass pipeline are connected to both ends of the pressure regulating pipeline, respectively. The compressed air input unit includes an air filter, an air compressor, and an air compressor outlet valve connected in sequence. The air compressor outlet is connected to a pressure gauge, and the outlet valve is connected to the air inlet of the pressure regulating unit.

9. A skid-mounted drying device for associated gas combustion in oil well casing according to claim 7, characterized in that, The associated gas drying unit, natural gas drying unit, vortex tube, drainage unit, low-temperature gas venting unit, pressure regulating unit, and gas manifold are all mounted on a skid-mounted chassis.

10. An oil well casing associated gas combustion system, comprising a wellhead, a heating furnace, and an external natural gas supply pipeline, wherein a casing gas valve is installed at the wellhead, characterized in that, It also includes a skid-mounted drying device for associated gas combustion in oil well casing as described in claim 1; The sleeve valve is connected to the associated gas drying unit; The natural gas pipeline is connected to the natural gas drying unit; The hot end of the vortex tube, the outlet of the natural gas pipeline and the low-temperature gas pipeline are connected to the inlet of the heating furnace.

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