Device for removing hydrogen sulfide from oilfield associated natural gas

Abstract

The present application relates to natural gas processing technical field, especially to a kind of hydrogen sulfide removal device in oilfield associated natural gas, including cylinder and the water tank being located in the lower end of cylinder and being communicated with cylinder, water tank is equipped with water in inside and its top is inserted with air inlet pipe, cylinder is equipped with the support rod that can move longitudinally in inside, the top packing layer is fixed in the top of support rod, multiple subsidiary packing layers are hung below top packing layer, the support rod is used to drive top packing layer and subsidiary packing layer to be lifted to immerse it in water, make its surface attach water and obtain uniform liquid film, to dissolve hydrogen sulfide and form sulfur ion, and top packing layer and subsidiary packing layer are used to promote sulfur ion oxidation and form sulfur element;The present application obtains uniform liquid film using lifting packing layer, and compared with leaching, there is no short circuit and no leaching dead angle, and the device has leaching and reaction absorption function simultaneously, hydrogen sulfide absorbed by water is also oxidized and removed, removal efficiency is higher than pure leaching effect and there is no secondary pollution.

Description

Technical Field

[0001] This invention relates to the field of natural gas processing technology, and in particular to a device for removing hydrogen sulfide from associated natural gas in oil fields. Background Technology

[0002] During oil extraction, natural gas and hydrogen sulfide are usually produced as byproducts. Small amounts of natural gas are not valuable enough to be directly discharged and could cause danger. However, storage and transportation are costly and labor-intensive. Therefore, they are usually disposed of by combustion. The presence of hydrogen sulfide generates pollutants such as sulfur dioxide, which cause air pollution. Therefore, it is necessary to remove hydrogen sulfide before combustion.

[0003] Currently, there are two main methods for treating natural gas containing hydrogen sulfide: wet desulfurization and dry desulfurization. Wet desulfurization is highly efficient but prone to causing secondary pollution. Furthermore, traditional spray absorption processes are prone to short circuits and dead zones, while submerged bubbling absorption requires a large amount of energy due to excessive resistance. CN203582823U discloses a device for treating hydrogen sulfide-containing natural gas, comprising a reaction tank and a dosing device, which absorbs hydrogen sulfide by spraying in a sodium hydroxide solution. While this method of absorbing hydrogen sulfide by adding sodium hydroxide is effective, it requires a large amount of chemical reagents and complex control conditions; otherwise, the reaction process can easily become uncontrollable, resulting in waste or ineffective treatment. Additionally, the generated sodium sulfide solution needs to be treated, which involves a large volume and is quite cumbersome. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: in order to overcome the problems that the existing desulfurization devices using spray absorption are prone to short circuits and dead zones, while the submerged bubbling absorption requires a lot of energy due to excessive resistance and is prone to secondary pollution, a hydrogen sulfide removal device for associated natural gas in oil fields is provided.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a hydrogen sulfide removal device in associated natural gas in oil fields, comprising a cylinder and a water tank located at the lower end of the cylinder and communicating with the cylinder;

[0006] The water tank is filled with water and has an air inlet pipe inserted at the top. Hydrogen sulfide dissolves in the water to form sulfur ions, and the air introduced through the air inlet pipe can oxidize the sulfur ions to form elemental sulfur.

[0007] The cylinder is equipped with a longitudinally movable support rod. A top packing layer is fixed to the top of the support rod, and multiple auxiliary packing layers are suspended below the top packing layer. The top packing layer and the auxiliary packing layers can move closer or further apart from each other, that is, adjacent packing layers are connected by flexible connectors, which can be pull ropes. The support rod is used to drive the top packing layer and the auxiliary packing layers to rise and fall so as to immerse them in water, so that water is attached to their surface to form a uniform liquid film, which dissolves hydrogen sulfide to form sulfur ions. The top packing layer and the auxiliary packing layers are used to promote the oxidation of sulfur ions to form elemental sulfur. The top of the cylinder is provided with an air outlet, and the bottom is provided with a drain outlet. The drain outlet is used to change water and discharge particulate impurities inside the cylinder. An air inlet for natural gas is provided above the drain outlet.

[0008] During operation, the support rod first descends, causing the top packing layer to move downwards. The auxiliary packing layer moves downwards along with the top packing layer, and the packing layers gradually approach each other until they are all immersed in water, causing water to adhere to their surfaces. Then, the support rod rises, lifting the top packing layer. The auxiliary packing layer also rises along with the top packing layer, and under the influence of gravity, the packing layers gradually move away from each other. The natural gas to be treated is continuously blown in through the inlet, and air is blown in through the air inlet pipe. The two mix to form a mixed airflow that passes through the auxiliary and top packing layers in sequence. The hydrogen sulfide in the airflow comes into contact with the liquid on the surface of the packing layers, dissolves into the liquid film, and is removed from the gas phase. Then, the top and auxiliary packing layers promote the oxidation of sulfur ions dissolved in the surface liquid layer to generate elemental sulfur. The air oxidizes the sulfur ions formed by hydrogen sulfide dissolved in the water, forming elemental sulfur precipitates. Finally, the up-and-down movement of the support rod causes the packing particles in the packing layers to shake, allowing the elemental sulfur on the surface to be shaken off and enter the water to precipitate. After accumulating to a certain amount, it is discharged from the drain outlet.

[0009] The above technical solution utilizes a rising and falling packing layer to obtain a uniform liquid film. Compared with rinsing, it has no short circuits or dead zones. Moreover, this device has both rinsing and reaction absorption functions. The hydrogen sulfide absorbed by the water is also oxidized and removed. The removal efficiency is higher than that of simple rinsing and there is no secondary pollution.

[0010] Furthermore, both the top packing layer and the auxiliary packing layer include a catalyst particle layer and a hydrophilic particle layer laid on top of it. The catalyst particle layer oxidizes sulfur ions in the surface liquid layer to generate elemental sulfur, and the hydrophilic particle layer can increase the amount of water adhering and extend the soaking cycle of the packing layer.

[0011] Furthermore, a surface water-adhering evaporation device is floating inside the cylinder. When the support rod drives the top packing layer and the auxiliary packing layer to descend and soak in water, the evaporation device is also pressed into the water and immersed, so that its surface is covered with water. When the natural gas to be treated is continuously blown in from the air inlet, the natural gas blows onto the evaporation device, which can make the liquid on its surface evaporate, thereby increasing the airflow humidity, reducing the evaporation of water on the surface of the packing layer by the airflow, and extending the water soaking cycle of the packing layer.

[0012] Furthermore, the volatilization device is a ring structure formed by bundling multiple hollow tubes. The hollow tubes can float on the water surface and have a diameter of 5-10 mm. They are made of plastic.

[0013] Furthermore, the water tank is filled with catalytic packing material for oxidizing sulfur ions. When the air blown in through the air pipe oxidizes the sulfur ions formed by hydrogen sulfide dissolved in the water, the catalytic packing material near the air pipe can catalyze the oxidation process of sulfur ions by the air, promote the oxidation of sulfur ions, and improve the oxidation efficiency.

[0014] Furthermore, both the catalyst particle layer and the catalyst filler are ceramic particles or activated carbon particles loaded with transition metal oxides.

[0015] Furthermore, a screen is provided at the connection between the water tank and the cylinder, which on the one hand allows the water tank and the cylinder to communicate, and on the other hand can be used to prevent the catalytic packing in the water tank from entering the cylinder.

[0016] Furthermore, the height of the air inlet is consistent with the liquid level in the cylinder, and the volatilization device can float on the water surface and is positioned directly opposite the air inlet. Natural gas blown in from the air inlet blows onto the volatilization device, which can promote the evaporation of moisture on its surface.

[0017] The beneficial effects of this invention are:

[0018] 1. This device requires no additional reagents and is suitable for field oil well operations;

[0019] 2. The movement of the packing layer in this device can shake off the elemental sulfur on its surface, making the catalyst surface less prone to agglomeration and failure.

[0020] 3. This device has both rinsing and reaction absorption functions. The hydrogen sulfide absorbed by the water is also oxidized and removed. The efficiency is higher than that of simple rinsing and there is no secondary pollution.

[0021] 4. This device has relatively low energy consumption. The airflow passes through the packing with relatively low resistance. The packing is submerged in water and then lifted, resulting in a uniform liquid film. Compared with rinsing, there is no short circuit or dead zone in rinsing. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] Figure 1 This is a schematic diagram of the structure of the present invention;

[0024] In the picture:

[0025] 1. Cylinder; 101. Air outlet; 102. Sewage outlet; 103. Air inlet; 2. Water tank; 201. Air inlet pipe; 3. Support rod; 4. Top packing layer; 5. Auxiliary packing layer; 6. Volatilization device; 7. Catalytic packing; 8. Screen; 9. Catalyst particle layer; 10. Hydrophilic particle layer; 11. Flexible connector. Detailed Implementation

[0026] The invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention in a schematic manner. Therefore, they only show the components relevant to the invention, and directions and references, such as up, down, left, right, etc., are only used to aid in the description of the features in the drawings. Therefore, the following specific embodiments are not intended to be restrictive, and the scope of the claimed subject matter is defined solely by the appended claims and their equivalents.

[0027] Example 1:

[0028] like Figure 1 As shown, the present invention is a hydrogen sulfide removal device in associated natural gas in an oil field, comprising a cylindrical body 1 and a water tank 2 located at the lower end of the body 1 and communicating with the body 1;

[0029] The water tank 2 is filled with water and has catalytic packing 7 for oxidizing sulfur ions inside. An air inlet pipe 201 is inserted at the top of the tank. A screen 8 is provided at the connection between the water tank 2 and the cylinder 1 to prevent the catalytic packing 7 in the water tank 2 from entering the cylinder 1. When hydrogen sulfide dissolves in the water to form sulfur ions, the air blown in from the air inlet pipe 201 oxidizes the sulfur ions formed by the hydrogen sulfide dissolved in the water. The catalytic packing 7 near the air inlet pipe 201 can catalyze the oxidation process of sulfur ions by the air, promote the oxidation of sulfur ions, and improve the oxidation efficiency.

[0030] The cylinder 1 is provided with a support rod 3 that can move longitudinally. The top of the support rod 3 is fixed with a top packing layer 4, and the bottom is connected to a linear reciprocating drive mechanism that drives it to rise and fall. That is, the support rod 3 is inserted from the bottom of the cylinder 1. Similarly, the bottom of the support rod 3 can be connected to the top packing layer 4, and the top can be connected to a linear reciprocating drive mechanism that drives it to rise and fall. That is, the support rod 3 is inserted from the top of the cylinder 1. In this embodiment, the support rod 3 is inserted from the bottom. The linear reciprocating drive mechanism can be, but is not limited to, a cylinder, a hydraulic cylinder, or an electric telescopic rod.

[0031] Multiple auxiliary packing layers 5 are suspended below the top packing layer 4. The top packing layer 4 and the auxiliary packing layers 5 can be close to or far from each other, that is, adjacent packing layers are connected by flexible connectors 11. The flexible connectors 11 can be, but are not limited to, ropes, etc. The auxiliary packing layers 5 are sleeved on the support rod 3, and their number can be two, three, or four, etc., which can be set according to the height of the cylinder 1 and the liquid level inside the cylinder 1. This embodiment does not limit this. The outer peripheral walls of the top packing layer 4 and the auxiliary packing layers 5 are attached to the inner peripheral wall of the cylinder 1 or have a small gap. The gap is designed to ensure that all natural gas entering the cylinder 1 is treated before being discharged. The support rod 3 is used to drive the top packing layer 4 and the auxiliary packing layer 5 to rise and fall so that they are submerged in water, so that water is attached to their surface to obtain a uniform liquid film, which dissolves hydrogen sulfide to form sulfur ions. The top packing layer 4 and the auxiliary packing layer 5 are used to promote the oxidation of sulfur ions. The top of the cylinder 1 is provided with an air outlet 101 and the bottom is provided with a drain outlet 102. The drain outlet 102 is used to change water and discharge particulate impurities inside the cylinder 1. An air inlet 103 for natural gas to enter is provided above the drain outlet 102.

[0032] Inside the cylinder 1, a surface-mounted evaporation device 6 is floating. The evaporation device 6 is a ring structure formed by multiple hollow tubes bundled together. The diameter of the hollow tubes is 5-10 mm and the material is plastic. The height of the air inlet 103 is consistent with the liquid level in the cylinder 1. The evaporation device 6 can float on the water surface and its position is directly opposite the air inlet 103. When the support rod 3 drives the top packing layer 4 and the auxiliary packing layer 5 to descend and soak in water, the evaporation device 6 is also pressed into the water and soaked, so that its surface is covered with water. When the natural gas to be treated is continuously blown in from the air inlet 103, the natural gas blows onto the evaporation device 6, which can make the liquid on its surface evaporate, thereby increasing the humidity of the airflow, reducing the evaporation of water on the surface of the packing layer by the airflow, and extending the soaking cycle of the packing layer.

[0033] Both the top packing layer 4 and the auxiliary packing layer 5 include a catalyst particle layer 9 and a hydrophilic particle layer 10 laid on top of it. The catalyst particle layer 9 oxidizes sulfur ions in the surface liquid layer to generate elemental sulfur, and the hydrophilic particle layer 10 can increase the amount of water adhering and prolong the soaking cycle of the packing layer.

[0034] The catalyst particle layer 9 and the catalyst filler 7 are both supports loaded with transition metal oxides, which can be, but are not limited to, ceramic particles or activated carbon particles loaded with transition metal oxides.

[0035] Working principle:

[0036] During operation, the support rod 3 first descends, causing the top packing layer 4 to move downwards. The auxiliary packing layer 5 moves downwards along with the top packing layer 4, and the packing layers gradually approach each other until they are all immersed in water, causing water to adhere to their surfaces. Then, the support rod 3 rises, lifting the top packing layer 4. The auxiliary packing layer 5 also rises along with the top packing layer 4, and under the influence of gravity, the packing layers gradually move away from each other. The natural gas to be treated is continuously blown in through the inlet 103, and air is blown in through the air inlet pipe 201. The two mix to form a mixed airflow that passes through the auxiliary packing layer 5 and the top packing layer 4 in sequence. The hydrogen sulfide in the airflow comes into contact with the liquid on the surface of the packing layer, dissolves into the liquid film, and is removed from the gas phase. At the same time, when the natural gas is continuously blown in through the inlet 103, the natural gas blows onto the volatilization device 6, which can cause the liquid on its surface to evaporate, thereby increasing the humidity of the airflow, reducing the evaporation of water on the surface of the packing layer, and extending the water immersion cycle of the packing layer.

[0037] Then, the top packing layer 4 and the auxiliary packing layer 5 promote the oxidation of sulfur ions dissolved in the surface liquid layer to generate elemental sulfur. The air oxidizes the sulfur ions formed by hydrogen sulfide dissolved in the water to form elemental sulfur precipitate.

[0038] Finally, the up-and-down movement of the support rod 3 causes the filler particles in the filler layer to shake, and the elemental sulfur on the surface can be shaken off, enter the water to precipitate, and after accumulating to a certain amount, it is discharged from the drain outlet 102.

[0039] The above description, based on the preferred embodiments of the present invention, provides inspiration. Those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification but must be determined according to the claims.

Claims

1. A device for removing hydrogen sulfide from associated natural gas in oil fields, characterized in that: Includes a cylindrical body (1) and a water tank (2) located at the lower end of the cylindrical body (1) and connected to the cylindrical body (1); The water tank (2) is filled with water and has an air inlet pipe (201) at its top. The air inlet pipe (201) is used to introduce air to oxidize the sulfur ions formed by the hydrogen sulfide dissolved in the water to form elemental sulfur. The cylinder (1) is provided with a longitudinally movable support rod (3). A top packing layer (4) is fixed on the top of the support rod (3). Multiple auxiliary packing layers (5) are suspended below the top packing layer (4) and distributed longitudinally. The top packing layer (4) and the auxiliary packing layer (5) can move closer or further away from each other. The support rod (3) is used to drive the top packing layer (4) and the auxiliary packing layer (5) to rise and fall so as to immerse them in water, so that water is attached to their surface to dissolve hydrogen sulfide and form sulfur ions. The top packing layer (4) and the auxiliary packing layer (5) are used to promote the oxidation of sulfur ions to form elemental sulfur. The top of the cylinder (1) is provided with an air outlet (101) and the bottom is provided with a sewage outlet (102). An air inlet (103) for natural gas to enter is provided above the sewage outlet (102). A volatilization device (6) with surface water attached is floating inside the cylinder (1). During operation, the support rod (3) first descends, causing the top packing layer (4) to move down. The auxiliary packing layer (5) moves down with the top packing layer (4), and the packing layers gradually approach each other until they are all immersed in water and the surface of the packing layers is covered with water. Then the support rod (3) rises and lifts the top packing layer (4). The auxiliary packing layer (5) is lifted up with the top packing layer (4), and the packing layers gradually move away from each other under the action of gravity. The natural gas to be treated is continuously blown in from the air inlet (103) and air is blown in from the air inlet pipe (201). The two mix to form a mixed airflow that passes through the auxiliary packing layer (5) and the top packing layer (4) in sequence. The hydrogen sulfide in the airflow comes into contact with the liquid on the surface of the packing layer and dissolves into the liquid film and is removed from the gas phase. At the same time, when the natural gas is continuously blown in from the air inlet (103), the natural gas blows onto the volatilization device (6), which can make the liquid on its surface volatilize, thereby increasing the humidity of the airflow, reducing the evaporation of water on the surface of the packing layer by the airflow, and extending the water soaking cycle of the packing layer.

2. The hydrogen sulfide removal device for associated natural gas in oil fields according to claim 1, characterized in that: The top packing layer (4) and the auxiliary packing layer (5) both include a catalyst particle layer (9) and a hydrophilic particle layer (10) laid on top of it.

3. The hydrogen sulfide removal device for associated natural gas in oil fields according to claim 1, characterized in that: The volatilization device (6) is a ring structure formed by bundling multiple hollow tubes.

4. The hydrogen sulfide removal device for associated natural gas in oil fields according to claim 2, characterized in that: The water tank (2) is filled with catalytic packing material (7) for oxidizing sulfur ions.

5. The hydrogen sulfide removal device for associated natural gas in oil fields according to claim 4, characterized in that: The catalyst particle layer (9) and the catalyst filler (7) are both ceramic particles or activated carbon particles loaded with transition metal oxides.

6. The hydrogen sulfide removal device for associated natural gas in oil fields according to claim 1, characterized in that: The connection between the water tank (2) and the cylinder (1) is provided with a screen (8).

7. The hydrogen sulfide removal device for associated natural gas in oil fields according to claim 1, characterized in that: The height of the air inlet (103) is consistent with the liquid level in the cylinder (1).

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