Sulfur-resistant and carbon dioxide-resistant gas injection and production wellhead device

Abstract

The invention belongs to the technical field of gas production wellhead devices, and particularly relates to a sulfur-resistant and carbon dioxide-resistant gas injection and production wellhead device which comprises an injection and production four-way assembly, a crossover flange assembly and a desanding assembly. The desanding assembly comprises a first pipe body, a second pipe body, a treatment box, a desanding barrel, one end of the desanding barrel, an inner spiral piece, a spiral groove, an air cylinder and an internally-tangent spiral blade. When the air pressure of the natural gas is reduced, the air cylinder pushes the internally-tangent spiral blade downwards through the bearing, the internally-tangent spiral blade rotates along the spiral groove in the downward pushing process, the path of the natural gas passing through the inner spiral blade is reduced, the centrifugal force of the natural gas is increased along with increase, and gravel in the natural gas can be thrown out of the sand removing barrel. Due to the fact that the pressure of the natural gas is reduced, a vortex-shaped gas column is formed on the shaft portion of the desanding cylinder and begins to diffuse, when the natural gas passes through the internally-tangent spiral blade, the internally-tangent spiral blade can guide the diffused gas column, the diffused gas column is gathered towards the shaft portion of the desanding cylinder again, the stability of the gas column is improved, and the influence of the gas column on gravel is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of gas production wellhead devices, and in particular relates to a sulfur and carbon dioxide resistant gas injection and production wellhead device. Background Art

[0002] In the process of oil and gas extraction, the gas injection and production wellhead device plays a vital role. The main function of the gas injection and production wellhead device is to inject carbon dioxide gas into the underground rock formation natural gas block through the oil layer casing. The principle is that the density of carbon dioxide is greater than the density of natural gas underground. By injecting carbon dioxide gas underground, the natural gas underground can float up while reducing the bottom hole temperature, reducing the pipe column gas and improving the gas production effect. After gas injection, the bottom hole temperature drops and the pipe column gas decreases, thereby increasing the gas recovery rate of the gas well and reducing the emission of pollutants.

[0003] Since the wellhead pressure of CO2-driven gas wells is relatively high, most of them are self-flowing wells. Although the main product is natural gas, the natural gas is mixed with gravel. The gravel will follow the natural gas to the wellhead at a high speed and cause serious impact on the main valve. For example, the patent with publication number CN115199233A mainly removes sand through a sand barrier plate. However, due to the high pressure of natural gas, the natural gas will impact the sand barrier plate during operation, causing the equipment to vibrate. Therefore, the above vibration problem is solved by installing a cyclone desander on the wellhead device. For example, the patent with publication number CN110479505A mainly uses the kinetic energy of the medium itself to form a cyclone inside the spiral desander to separate the gravel. When the spiral desander is working, a vortex-shaped gas column will be formed in the central axis. This phenomenon is a normal fluid mechanics performance. When the natural gas pressure changes, such as the pressure decreases, the shape of the gas column begins to change, which is easy to cause gravel to splash, thereby affecting the separation effect of the desander; at the same time, the reduction of natural gas pressure will cause the gas flow rate to slow down, resulting in a decrease in the centrifugal force of the sand particles in the cyclone. This results in the sand particles being unable to be effectively thrown toward the wall and settled, thereby reducing the sand removal efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a mica tape wrapping machine for cable production which has a simple structure and is capable of solving the technical problems in the prior art.

[0005] The purpose of the present invention can be achieved by the following technical solutions: a sulfur-resistant and carbon dioxide-resistant gas injection and production wellhead device, which includes an injection and production four-way assembly and a conversion flange assembly installed thereon, the conversion flange assembly is connected to a sand removal assembly, the sand removal assembly is connected to an interface of the four-way pipe through a manual gate valve, and the other interfaces of the four-way pipe are respectively installed with a threaded flange, a gas production tree cap and an instrument flange, and an elbow is installed between the four-way pipe and the instrument flange;

[0006] The sand removal assembly includes a tube body 1 and a tube body 2 installed thereon, a processing box is installed at the bottom of the tube body 2, a sand removal cylinder is fixedly installed inside the tube body 1, one end of the sand removal cylinder is connected to the four-way pipe through an exhaust port, and the other end of the exhaust port is connected to the conversion flange assembly through an air inlet, an inner spiral piece is installed inside the sand removal cylinder, a spiral groove is provided inside the sand removal cylinder, the inner spiral piece and the spiral groove are arranged alternately, a cylinder is installed inside the tube body 2, the cylinder is connected to the inscribed spiral blade through a bearing, an inclination angle is set inside the inscribed spiral blade, and the inscribed spiral blade slides in the spiral groove.

[0007] As a further optimization or improvement of the present solution, the interior of the inscribed spiral blade is cut in a conical shape.

[0008] As a further optimization or improvement of this solution, a spiral propulsion piece is rotatably installed inside the tube body, and the spiral propulsion piece is located between the outer wall of the sand removal cylinder and the inner wall of the tube body. The inner and outer sides of the spiral propulsion piece are respectively sealed with the outer wall of the sand removal cylinder and the inner wall of the tube body, and a part of the spiral propulsion piece extends into the processing box.

[0009] As a further optimization or improvement of this solution, a gear ring is installed on the outer wall of the sand removing cylinder, a transmission box is installed on the outer side of the tube body, an electric motor is installed inside the transmission box, the output shaft of the motor is connected to the transmission gear, the transmission gear is meshed with the gear ring, and a spiral propulsion piece is installed at the bottom of the gear ring, and the spiral propulsion piece and the spiral groove are arranged alternately.

[0010] As a further optimization or improvement of this solution, the processing box is connected to the exhaust port through an exhaust pipe.

[0011] As a further optimization or improvement of this solution, an infusion port is installed at the bottom of the processing box, and water is injected into the processing box.

[0012] As a further optimization or improvement of this solution, sealing strips are respectively installed on the inner and outer sides of the spiral propulsion piece, and the sealing strips are respectively connected to the outer wall of the sand removal cylinder and the inner wall of the tube body.

[0013] Beneficial effects of the present invention:

[0014] (1) When the present invention is in use, the manual gate valve is opened, and the sand-carrying natural gas flows from the conversion flange assembly to the four-way pipe, so that it passes through the sand removal assembly, and the natural gas enters the sand removal assembly through the air inlet, so that the natural gas enters the sand removal cylinder, and the natural gas entering the sand removal cylinder forms a vortex and generates an inertial force under the action of the inner spiral blade, and the sand and gravel in the natural gas are thrown out of the sand removal cylinder through the inertial force. In the initial state, the blades at the bottom of the inner spiral blade are located in the spiral groove at the top of the sand removal cylinder, so that the top of the sand removal cylinder is an overlapping arrangement of the inner spiral blade and the inner spiral blade. At this time, when the natural gas passes through the top of the sand removal cylinder, the path of the natural gas is reduced, and the corresponding inertial force of the natural gas when passing through the top of the sand removal cylinder increases, which is conducive to the throwing out of small particles of sand and gravel.

[0015] (2) When the natural gas pressure decreases, the cylinder is started, and the cylinder pushes the inner spiral blade downward through the bearing. The inner spiral blade rotates along the spiral groove during the pushing process. With the cooperation of the spiral groove and the inner spiral blade, the inner spiral blade is completely rotated into the spiral groove, so that the inner spiral blade overlaps with the desander. At this time, the two adjacent inner spiral blades are separated by the inner spiral blade. When the natural gas enters the desander, the path of the natural gas through the inner spiral blade is reduced, and its centrifugal force increases, which is conducive to the sand and gravel in the natural gas being thrown out of the desander. Due to the decrease in the natural gas pressure, a vortex-shaped gas column is formed at the axis of the desander and begins to diffuse. When the natural gas passes through the inner spiral blade, the inner spiral blade guides the diffused gas column to gather toward the axis of the desander again, thereby increasing the stability of the gas column and reducing the impact of the gas column on the sand and gravel. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings.

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0018] Figure 2 Schematic diagram of the sand removal component structure.

[0019] Figure 3 Schematic diagram of the internal structure of the sand removal component.

[0020] Figure 4 This is an exploded view of the overall structure of the sand removal component.

[0021] Figure 5 It is a cross-sectional view of the sand removal cylinder structure.

[0022] Figure 6 It is a schematic cross-sectional diagram of the inscribed spiral blade structure.

[0023] Figure 7 This is the inscribed spiral blade and matching diagram.

[0024] Figure 8 Schematic diagram of the connection between the spiral propeller and the gear ring.

[0025] Fig. 9 for Figure 8 A magnified view of the structure of part A.

[0026] The following are marked in the figure: 1. Injection and production four-way assembly; 2. Conversion flange assembly; 3. Manual gate valve; 4. Four-way pipe; 5. Threaded flange; 6. Gas production tree cap; 7. Elbow; 8. Instrument flange; 9. Desanding assembly; 901. Pipe body one; 902. Pipe body two; 903. Processing box; 904. Desanding cylinder; 905. Air inlet; 906. Exhaust port; 907. Exhaust pipe; 908. Motor; 909. Transmission box; 910. Cylinder; 911. Bearing; 912. Inscribed spiral blade; 913. Transmission gear; 914. Gear ring; 915. Spiral propulsion piece; 916. Spiral groove; 917. Infusion port; 918. Inner spiral piece; 919. Sealing strip. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1-Figure 7 A sulfur and carbon dioxide resistant gas injection and production wellhead device, comprising an injection and production four-way assembly 1 and a conversion flange assembly 2 installed thereon, the conversion flange assembly 2 is connected to a sand removal assembly 9, the sand removal assembly 9 is connected to an interface of a four-way pipe 4 through a manual gate valve 3, the other interfaces of the four-way pipe 4 are respectively installed with a threaded flange 5, a gas production tree cap 6 and an instrument flange 8, and an elbow 7 is installed between the four-way pipe 4 and the instrument flange 8;

[0029] The sand removal component 9 includes a tube body 901 and a tube body 902 installed thereon, a processing box 903 is installed at the bottom of the tube body 902, a sand removal cylinder 904 is fixedly installed inside the tube body 901, one end of the sand removal cylinder 904 is connected to the four-way pipe 4 through an exhaust port 906, and the other end of the exhaust port 906 is connected to the conversion flange component 2 through an air inlet 905, an inner spiral piece 918 is installed inside the sand removal cylinder 904, a spiral groove 916 is provided inside the sand removal cylinder 904, the inner spiral piece 918 and the spiral groove 916 are arranged alternately, a cylinder 910 is installed inside the tube body 902, the cylinder 910 is connected to the inner spiral blade 912 through a bearing 911, an inclination angle is set inside the inner spiral blade 912, and the inner spiral blade 912 slides in the spiral groove 916.

[0030] Specifically, the interior of the inscribed spiral blade 912 is conically cut.

[0031] It should be noted that a sand discharge groove is provided on the side wall of the sand removal cylinder 904. The sand discharge groove is spirally provided similarly to the spiral groove 916. The sand discharge groove is located at the connection portion between the inner spiral sheet 918 and the inner wall of the sand removal cylinder 904. When the natural gas pressure remains unchanged, the spiral groove 916 can serve as a sand discharge groove.

[0032] It should be noted that the present invention optimizes the dual main valve into a single main valve, namely the elbow 7 and the instrument flange 8, and the unit price is greatly reduced after optimization. The injection and production four-way assembly 1, the four-way pipe 4, the elbow 7 and other main pressure-bearing parts in the present invention are made of high-strength corrosion-resistant alloy materials, which can withstand high pressure in harsh corrosive environments such as high sulfur and carbon dioxide. A four-layer sealing structure is adopted between the internal suspension assembly of the conversion flange assembly 2 and the four-way pipe 4, including two stainless steel metal sealing rings, two high-performance rubber BT sealing rings and O-ring seals, which can effectively prevent the leakage of corrosive gases such as hydrogen sulfide and carbon dioxide. The overall inner and outer surfaces of the present invention are coated with a molybdenum disulfide anti-corrosion coating to enhance its resistance to low temperature and corrosion.

[0033] When the present invention is in use, the manual gate valve 3 is opened, and the sand-carrying natural gas flows from the conversion flange assembly 2 to the four-way pipe 4, so that it passes through the sand removal assembly 9, and the natural gas enters the sand removal assembly 9 through the air inlet 905, so that the natural gas enters the sand removal cylinder 904, and the natural gas entering the sand removal cylinder 904 forms a vortex and generates inertial force under the action of the inner spiral sheet 918, and the sand and gravel in the natural gas are thrown out of the sand removal cylinder 904 through the inertial force and enter the processing box 903.

[0034] Specifically, the blade size at the bottom of the inscribed spiral blade 912 is the same as that of the inner spiral piece 918. In the initial state, the blade at the bottom of the inscribed spiral blade 912 is located in the spiral groove 916 at the top of the sand removal cylinder 904, so that the top of the sand removal cylinder 904 is a double spiral blade overlapping the inner spiral piece 918 and the inscribed spiral blade 912. At this time, when the natural gas passes through the top of the sand removal cylinder 904, the path of the natural gas is reduced, and the corresponding inertia force of the natural gas when passing through the top of the sand removal cylinder 904 is increased, which is conducive to the removal of small particles of sand and gravel.

[0035] When the natural gas pressure decreases, the flow rate of the gas slows down, and the centrifugal force generated by the inner spiral blade 918 decreases. At the same time, the vortex-shaped gas column formed on the axis of the sand removal cylinder 904 is deformed under the action of the pressure change, that is, the vortex-shaped gas column formed on the axis of the sand removal cylinder 904 begins to diffuse, and the sand removal efficiency decreases accordingly.

[0036] Therefore, the present invention starts the cylinder 910, and the cylinder 910 pushes the inner spiral blade 912 downward through the bearing 911. The inner spiral blade 912 rotates along the spiral groove 916 during the pushing process. Under the cooperation of the spiral groove 916 and the inner spiral blade 912, the inner spiral blade 912 rotates into the spiral groove 916, so that the inner spiral blade 912 overlaps with the sand removal cylinder 904. At this time, two adjacent inner spiral blades 918 are separated by the inner spiral blade 912. When the natural gas enters the sand removal cylinder 904, the path of the natural gas through the inner spiral blade 918 is reduced, and its centrifugal force increases, which is conducive to the sand and gravel in the natural gas being thrown out of the sand removal cylinder 904; due to the reduction of the natural gas pressure, a vortex-shaped gas column is formed at the axis of the sand removal cylinder 904 and begins to diffuse, see Figure 6 When the natural gas passes through the inscribed spiral blades 912, the inscribed spiral blades 912 will guide the diffused gas column to gather toward the axis of the sand removal cylinder 904 again, thereby increasing the stability of the gas column and reducing the impact of the gas column on the sand.

[0037] See also Figure 3-Figure 9 A spiral propulsion piece 915 is rotatably installed inside the tube body 901, and the spiral propulsion piece 915 is located between the outer wall of the sand removal cylinder 904 and the inner wall of the tube body 901. The inner and outer sides of the spiral propulsion piece 915 are respectively sealed with the outer wall of the sand removal cylinder 904 and the inner wall of the tube body 901, and a part of the spiral propulsion piece 915 extends into the processing box 903.

[0038] Specifically, a gear ring 914 is installed on the outer wall of the sand removal cylinder 904, a transmission box 909 is installed on the outer side of the tube body 901, a motor 908 is installed inside the transmission box 909, an output shaft of the motor 908 is connected to a transmission gear 913, the transmission gear 913 is meshed with the gear ring 914, a spiral propulsion piece 915 is installed at the bottom of the gear ring 914, and the spiral propulsion piece 915 and the spiral groove 916 are arranged alternately.

[0039] Specifically, sealing strips 919 are installed on both sides of the inner and outer sides of the spiral propulsion piece 915, and the sealing strips 919 are connected to the outer wall of the sand removal cylinder 904 and the inner wall of the tube body 1 901 respectively.

[0040] It should be noted that when the natural gas passes through the sand removal cylinder 904, the motor 908 runs, and the motor 908 drives the spiral propulsion piece 915 to rotate through the ring gear 914. The sand and gravel thrown out through the sand discharge groove or the spiral groove 916 will first enter the spiral propulsion piece 915 between the sand removal cylinder 904 and the pipe body 901. As the spiral propulsion piece 915 rotates, the sand and gravel are transported to the processing box 903. Since the spiral groove 916, the sand discharge groove and the spiral propulsion piece 915 are all spiral-shaped, the sand and gravel thrown out from the top of the sand removal cylinder 904 and the gravel thrown out from the bottom of the sand removal cylinder 904 can be simultaneously transported toward the manual gate valve 3 through the rotation of the spiral propulsion piece 915, so as to prevent the sand and gravel thrown out from the top of the sand removal cylinder 904 from entering the sand removal cylinder 904 through the bottom of the sand removal cylinder 904.

[0041] See also Figure 3 The processing box 903 is connected to the exhaust port 906 through the exhaust pipe 907.

[0042] Specifically, an infusion port 917 is installed at the bottom of the processing box 903, and water is injected into the processing box 903.

[0043] It should be noted that natural gas contains high concentrations of hydrogen sulfide gas, which can easily corrode wellhead seals and pipe walls, reducing the service life of the wellhead device. Therefore, when natural gas generates centrifugal force through the inner spiral blade 918, since the molecular mass of hydrogen sulfide gas in natural gas is greater than that of methane, part of the hydrogen sulfide gas in the natural gas will be thrown into between the spiral propulsion blades 915 along with the gravel. As the spiral propulsion blades 915 rotate, the methane and hydrogen sulfide in the natural gas are transported together with the gravel into the treatment box 903 and into the water inside the treatment box 903. Since hydrogen sulfide gas is easily soluble in water, while methane, the main component of natural gas, is not easily soluble in water, and the relative density of methane is less than that of air, methane is discharged from the water through the exhaust pipe 907 and the exhaust port 906 to the sand removal component 9, effectively reducing the concentration of hydrogen sulfide in the natural gas, reducing the corrosion of seals and pipe walls by high concentrations of hydrogen sulfide, and increasing the service life of the device. See Figure 3 Since a part of the spiral propulsion piece 915 is located in the processing box 903, the rotation of the spiral propulsion piece 915 will stir the liquid inside the processing box 903 to generate a vortex. When drainage is required, the infusion port 917 is opened, and the gravel in the water is quickly discharged from the processing box 903 through the vortex.

[0044] It should be noted that two processing boxes 903 are set at the bottom of the processing box 903, one is used to supply water into the processing box 903, and the other is used to discharge water from the processing box 903. After the water in the processing box 903 is saturated, the two processing boxes 903 are filled with water and discharged at the same time to ensure the liquid level height of the processing box 903 and the removal efficiency of hydrogen sulfide.

[0045] The implementation principle of the present invention is:

[0046] When the present invention is in use, the manual gate valve 3 is opened, and the sand-carrying natural gas flows from the conversion flange assembly 2 to the four-way pipe 4, so that it passes through the sand removal assembly 9, and the natural gas enters the sand removal assembly 9 through the air inlet 905, so that the natural gas enters the sand removal cylinder 904, and the natural gas entering the sand removal cylinder 904 forms a vortex and generates inertial force under the action of the inner spiral sheet 918, and the sand and gravel in the natural gas are thrown out of the sand removal cylinder 904 through the inertial force and enter the processing box 903.

[0047] The blade size at the bottom of the inscribed spiral blade 912 is the same as that of the inner spiral piece 918. In the initial state, the blade at the bottom of the inscribed spiral blade 912 is located in the spiral groove 916 at the top of the sand removal cylinder 904, so that the top of the sand removal cylinder 904 is a double spiral blade overlapping the inner spiral piece 918 and the inscribed spiral blade 912. At this time, when the natural gas passes through the top of the sand removal cylinder 904, the path of the natural gas is reduced, and the corresponding inertia force of the natural gas when passing through the top of the sand removal cylinder 904 is increased, which is conducive to the removal of small particles of sand and gravel.

[0048] When the natural gas pressure decreases, the flow rate of the gas slows down, and the centrifugal force generated by the inner spiral blade 918 decreases. At the same time, the vortex-shaped gas column formed on the axis of the sand removal cylinder 904 is deformed under the action of the pressure change, that is, the vortex-shaped gas column formed on the axis of the sand removal cylinder 904 begins to diffuse, and the sand removal efficiency decreases accordingly. Start the cylinder 910, and the cylinder 910 pushes the inner spiral blade 912 downward through the bearing 911. The inner spiral blade 912 rotates along the spiral groove 916 during the pushing process. Under the cooperation of the spiral groove 916 and the inner spiral blade 912, the inner spiral blade 912 rotates into the spiral groove 916, so that the inner spiral blade 912 overlaps with the desander cylinder 904. At this time, two adjacent inner spiral blades 918 are separated by the inner spiral blade 912. When the natural gas enters the desander cylinder 904, the path of the natural gas through the inner spiral blade 918 is reduced, and its centrifugal force increases, which is conducive to the sand and gravel in the natural gas to be thrown out of the desander cylinder 904; due to the decrease in natural gas pressure, a vortex-shaped gas column is formed at the axis of the desander cylinder 904 and begins to diffuse, see Figure 6 When the natural gas passes through the inscribed spiral blades 912, the inscribed spiral blades 912 will guide the diffused gas column to gather toward the axis of the sand removal cylinder 904 again, thereby increasing the stability of the gas column and reducing the impact of the gas column on the sand.

[0049] When the natural gas passes through the sand removal cylinder 904, the motor 908 runs, and the motor 908 drives the spiral propulsion piece 915 to rotate through the ring gear 914. The sand and gravel thrown out through the sand discharge groove or the spiral groove 916 will first enter the spiral propulsion piece 915 between the sand removal cylinder 904 and the pipe body 901. As the spiral propulsion piece 915 rotates, the sand and gravel are transported to the processing box 903. Since the spiral groove 916, the sand discharge groove and the spiral propulsion piece 915 are all spiral-shaped, the sand and gravel thrown out from the top of the sand removal cylinder 904 and the sand and gravel thrown out from the bottom of the sand removal cylinder 904 can be simultaneously transported toward the manual gate valve 3 through the rotation of the spiral propulsion piece 915, so as to prevent the sand and gravel thrown out from the top of the sand removal cylinder 904 from entering the sand removal cylinder 904 through the bottom of the sand removal cylinder 904.

[0050] When the natural gas generates centrifugal force through the inner spiral blade 918, since the molecular mass of hydrogen sulfide gas in the natural gas is greater than that of methane, part of the hydrogen sulfide gas in the natural gas will be thrown into the space between the spiral propulsion blades 915 along with the gravel. As the spiral propulsion blades 915 rotate, the methane and hydrogen sulfide in the natural gas are transported together with the gravel into the treatment box 903 and sent into the water inside the treatment box 903. Since hydrogen sulfide gas is easily soluble in water, while methane, the main component of natural gas, is not easily soluble in water, and the relative density of methane is lower than that of air, methane is discharged from the water through the exhaust pipe 907 and the exhaust port 906 to the sand removal component 9, effectively reducing the concentration of hydrogen sulfide in the natural gas, reducing the corrosion of the seal and the pipe wall by high concentration of hydrogen sulfide, and improving the service life of the device. Figure 3 Since a part of the spiral propulsion piece 915 is located in the processing box 903, the rotation of the spiral propulsion piece 915 will stir the liquid inside the processing box 903 to generate a vortex. When drainage is required, the infusion port 917 is opened, and the gravel in the water is quickly discharged from the processing box 903 through the vortex.

[0051] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A sulfur and carbon dioxide resistant gas injection and production wellhead device, characterized by: It comprises an injection and production four-way assembly (1) and a conversion flange assembly (2) installed thereon, the conversion flange assembly (2) is connected to a sand removal assembly (9), the sand removal assembly (9) is connected to one interface of a four-way pipe (4) through a manual gate valve (3), the other interfaces of the four-way pipe (4) are respectively installed with a threaded flange (5), a gas production tree cap (6) and an instrument flange (8), and an elbow (7) is installed between the four-way pipe (4) and the instrument flange (8); The sand removal assembly (9) comprises a pipe body 1 (901) and a pipe body 2 (902) mounted thereon, a processing box (903) is mounted at the bottom of the pipe body 2 (902), a sand removal cylinder (904) is fixedly mounted inside the pipe body 1 (901), one end of the sand removal cylinder (904) is connected to the four-way pipe (4) through an exhaust port (906), and the other end of the exhaust port (906) is connected to the conversion flange assembly (2) through an air inlet (905), and the inside of the sand removal cylinder (904) is provided with a plurality of air-conducting members. An inner spiral blade (918) is installed in the first part, a spiral groove (916) is provided inside the sand removal cylinder (904), the inner spiral blade (918) and the spiral groove (916) are arranged alternately, a cylinder (910) is installed inside the second tube body (902), the cylinder (910) is connected to the inner spiral blade (912) through a bearing (911), an inclination angle is set inside the inner spiral blade (912), and the inner spiral blade (912) is located in the spiral groove (916) and slides.

2. The sulfur and carbon dioxide resistant gas injection and production wellhead device according to claim 1, characterized in that: The interior of the inscribed spiral blade (912) is in the shape of a cone.

3. The sulfur and carbon dioxide resistant gas injection and production wellhead device according to claim 1, characterized in that: A spiral propulsion piece (915) is rotatably installed inside the tube body (901). The spiral propulsion piece (915) is located between the outer wall of the sand removal cylinder (904) and the inner wall of the tube body (901). The inner and outer sides of the spiral propulsion piece (915) are respectively sealed with the outer wall of the sand removal cylinder (904) and the inner wall of the tube body (901). A part of the spiral propulsion piece (915) extends into the processing box (903).

4. The sulfur and carbon dioxide resistant gas injection and production wellhead device according to claim 1, characterized in that: A gear ring (914) is installed on the outer wall of the sand removing cylinder (904), a transmission box (909) is installed on the outer side of the tube body (901), a motor (908) is installed inside the transmission box (909), an output shaft of the motor (908) is connected to a transmission gear (913), the transmission gear (913) is meshed with the gear ring (914), a spiral propulsion piece (915) is installed at the bottom of the gear ring (914), and the spiral propulsion piece (915) and the spiral groove (916) are arranged alternately.

5. The sulfur and carbon dioxide resistant gas injection and production wellhead device according to claim 1, characterized in that: The processing box (903) is connected to the exhaust port (906) via an exhaust pipe (907).

6. The sulfur and carbon dioxide resistant gas injection and production wellhead device according to claim 1, characterized in that: The bottom of the treatment box (903) is provided with an infusion port (917), and water is injected into the treatment box (903).

7. The sulfur and carbon dioxide resistant gas injection and production wellhead device according to claim 4, characterized in that: Sealing strips (919) are installed on both the inner and outer sides of the spiral propulsion piece (915), and the sealing strips (919) are respectively connected to the outer wall of the sand removal cylinder (904) and the inner wall of the tube body (901).

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