Aeration deoxygenization device for oilfield produced water

Abstract

The invention relates to an oilfield produced water nitrogen aeration and oxygen removal device which comprises a liquid storage tank, an aeration head is arranged on the lower portion of the inner side of the liquid storage tank, a rotational flow degasser is arranged on the upper portion of an inner cavity of the liquid storage tank, and an inlet of the aeration head and an inlet of the rotational flow degasser are connected with a gas inlet pipeline and a liquid inlet pipeline respectively; and the liquid outlet pipeline is fixedly inserted into the lower part of the outer side of the liquid storage tank. According to the equipment provided by the embodiment of the invention, oxygen in water can be replaced and discharged by utilizing a nitrogen air floatation principle, so that the oxygen content in the water is reduced. Nitrogen with extremely high content in the atmosphere is used as an inert gas raw material and is uniformly injected from the bottom of a liquid storage tank through an injection system, so that the nitrogen moves upwards from the bottom of the liquid storage tank, oxygen is discharged into the atmosphere from a fireproof ventilation cap, and the oxygen content in produced water is reduced, so that the corrosion rate of produced water treatment equipment, injection equipment and an injection pipeline is reduced; the safety and environmental protection hidden dangers in the oilfield produced water treatment and injection process are reduced.

Description

Technical Field

[0001] The present application relates to the technical field of oilfield produced water treatment, and in particular to an oilfield produced water nitrogen aeration and deoxygenation device. Background Art

[0002] The oilfield water system is responsible for the mission of fully ensuring that the oilfield development "injects good water and injects enough water". The amount and quality of injected water directly affect the development effect. With the application of tertiary oil recovery technology in oilfield development, the quality of incoming water has become more complicated and more difficult to handle. At the same time, the oxygen content index of the outflowing water quality has become more stringent. Therefore, we proposed a nitrogen aeration and deoxygenation device for oilfield produced water. Summary of the invention

[0003] The present application provides an oilfield produced water aeration and deoxygenation device to solve the problems raised in the background technology.

[0004] In order to solve the above technical problems or at least partially solve the above technical problems, the present application provides an oilfield produced water aeration and deoxygenation device, comprising:

[0005] A liquid storage tank, wherein an aeration head is provided at the lower inner part of the liquid storage tank, a cyclone degasser is provided at the upper inner part of the liquid storage tank, and the inlets of the aeration head and the cyclone degasser are connected to an air inlet pipeline and a liquid inlet pipeline respectively;

[0006] A liquid outlet pipeline is fixedly plugged into the lower part of the outer side of the liquid storage tank, and a sampling pipeline is also arranged on the liquid outlet pipeline.

[0007] Optionally, a gas pressure gauge and a gas flow meter are also provided on the air intake pipeline.

[0008] Optionally, a flow meter and a Y-type filter are further provided on the liquid inlet pipeline, and the flow meter is arranged on the outlet side of the Y-type filter.

[0009] Optionally, a sewage pipe is also connected to the lower side of the liquid storage tank, and a switch valve is provided on the sewage pipe.

[0010] Optionally, a fire-resistant and breathable cap is provided on the upper side of the liquid storage tank.

[0011] Optionally, an overflow pipeline is provided on the upper outer side of the liquid storage tank.

[0012] Optionally, the lower portion of the liquid storage tank is fixedly connected to the trolley mechanism via a fixing clamp.

[0013] Optionally, the trolley mechanism includes a base plate, wheels and armrests, the wheels are fixedly connected to the four corners of the base plate, and the armrest is fixedly connected to the right side of the upper end of the base plate.

[0014] Optionally, the middle portion of the upper end of the base plate is fixedly connected to the liquid storage tank.

[0015] Optionally, a sampling valve is provided on the sampling pipeline.

[0016] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0017] The device provided in the embodiment of the present application can utilize the nitrogen flotation principle to displace and discharge the oxygen in the water, thereby reducing the oxygen content in the water. Using nitrogen with a very high content in the atmosphere as an inert gas raw material, the injection system is uniformly injected from the bottom of the liquid storage tank, so that the nitrogen moves upward from the bottom of the liquid storage tank, and the squeezed oxygen also moves upward, and finally the oxygen is discharged into the atmosphere from the fireproof breathable cap, reducing the oxygen content in the produced water, thereby reducing the corrosion rate of the produced water treatment equipment, injection equipment, and injection pipeline, and reducing the safety and environmental protection risks in the oil field produced water treatment and injection process. The raw material required for the operation of the equipment is only nitrogen. Compared with other inert gases that can replace oxygen, nitrogen has a very high content in the atmosphere, a simple preparation method, a low price, and a high economy. And a produced water deoxygenation device includes two efficient deoxygenation methods of cyclone degassing and nitrogen aeration degassing. The overall process is simple and efficient, the cost is low, and it has good process adaptability in various oil field produced water treatment stations.

[0018] The equipment can be widely used in comprehensive oil-containing produced water deoiling treatment in the petrochemical industry, oil field oil production reinjection water deoiling treatment, crude oil dehydration oily wastewater treatment, crude oil deoxygenation wastewater treatment in oil refining and chemical industry, and other precision treatments. The structure of the invention is reasonable and simple, and it is easy to manufacture, maintain and move. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] Figure 1 This is an overall structural diagram of an oilfield produced water aeration and deoxygenation device.

[0022] In the figure: 1. flow meter; 2. Y-type filter; 3. gas pressure gauge; 4. gas flow meter; 5. liquid inlet pipeline; 6. air inlet pipeline; 7. drain pipe; 8. fire-retardant vent cap; 9. overflow pipeline; 10. liquid outlet pipeline; 11. fixing clamp; 12. bottom plate; 13. wheel; 14. cyclone degasser; 15. liquid storage tank; 16. aeration head; 17. sampling pipeline; 18. handrail. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0024] Various embodiments of the present application may exist in the form of a range. It should be understood that the description in the form of a range is only for convenience and simplicity and should not be understood as a hard limit to the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single values ​​within the range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which are applicable regardless of the range. In addition, whenever a numerical range is indicated in the present application, it is meant to include any quoted numbers (fractions or integers) within the indicated range. Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present application, etc., can be purchased from the market or can be prepared by existing methods.

[0025] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the present application, the terms "include", "comprise", etc. refer to "including but not limited to". In the present application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In the present application, "and / or" describes the association relationship of the associated objects, indicating that three relationships may exist, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A, B can be singular or plural. In the present application, "at least one" refers to one or more, and "plural" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of singular items or plural items. For example, "at least one of a, b, or c" or "at least one of a, b and c" can both mean: a, b, c, ab, i.e. a and b, ac, bc or abc, where a, b, c can be single or plural, respectively.

[0026] like Figure 1 As shown, the embodiment of the present application provides an oilfield produced water aeration and deoxygenation device, characterized in that it includes:

[0027] A liquid storage tank 15, wherein an aeration head 16 is disposed at the lower inner portion of the liquid storage tank 15, and a cyclone degasser 14 is disposed at the upper inner portion of the inner cavity of the liquid storage tank 15, wherein the inlets of the aeration head 16 and the cyclone degasser 14 are connected to the air inlet line 6 and the liquid inlet line 5 respectively;

[0028] The liquid outlet pipeline 10 is fixedly plugged into the lower outer portion of the liquid storage tank 15 , and a sampling pipeline 17 is also provided on the liquid outlet pipeline 10 .

[0029] Specifically: the liquid outlet pipeline 10 is connected to the lower part of the liquid storage tank 15 by means of a flange, and is used to transport the produced water after being treated and qualified;

[0030] The aeration head 16 disperses and aerates the nitrogen into the liquid storage tank 15;

[0031] The liquid storage tank 15 can be made of steel or PVC material, and is used to store the produced water to be processed. If the liquid storage tank 15 is made of PVC material, the body is transparent and colorless, and a liquid level gauge is not required. Other materials need to be equipped with a liquid level gauge to check the liquid level in the liquid storage tank 15;

[0032] The cyclone degasser 14 is installed on the top of the liquid storage tank 15 and connected to the liquid inlet pipe 6 for preliminary treatment of the produced water. The installation method is to fix it inside the top plate of the liquid storage tank 15 with screws;

[0033] The material of the liquid inlet pipeline 5 can be carbon steel or PVC. The size of the liquid inlet pipeline 5 can be determined according to the amount of produced water to be treated. The liquid inlet pipeline 5 is mainly responsible for transporting the produced water to the liquid storage tank 15. The source of the liquid inlet pipeline 5 is provided with a regulating valve of the same specification as the pipeline, which is used to adjust the liquid inlet amount of the liquid storage tank 15. The liquid inlet port can be connected to the produced water pipeline to be treated by flange, slip or welding. The end of the liquid inlet pipeline 5 is connected to the liquid storage tank 15 by farad method, and the liquid inlet pressure is 0 to 0.5Mpa.

[0034] like Figure 1 As shown: the air intake pipeline 6 is also provided with a gas pressure gauge 3 and a gas flow meter 4.

[0035] Specifically: the gas pressure gauge 3 is used to detect the nitrogen pressure in the pipeline. To facilitate the later verification and maintenance, it is connected to the air intake pipeline 6 by threading, and its installation position is located downstream of the gas flow meter 4;

[0036] The gas flow meter 4 is used to measure the nitrogen intake volume. To facilitate later verification and maintenance, it is connected to the intake pipe 6 by means of a flange.

[0037] like Figure 1 As shown: the liquid inlet pipeline 5 is also provided with a flow meter 1 and a Y-type filter 2, and the flow meter 1 is arranged at the outlet side of the Y-type filter 2.

[0038] Specifically: the flow meter 1 is used to measure the flow rate of produced water. To facilitate the later verification and maintenance, the flow meter 1 is connected to the liquid inlet pipe 5 by a flange to measure the liquid inlet flow rate;

[0039] The Y-type filter 2 can be made of steel or PVC and is installed on the liquid inlet pipe 5 by welding or fusion. The installation position is located downstream of the regulating valve and is used to filter impurities in the incoming liquid.

[0040] like Figure 1 As shown: a sewage pipe 7 is also plugged into the lower side of the liquid storage tank 15, and a switch valve is provided on the sewage pipe 7.

[0041] Specifically, the sewage pipe 7 is connected to the bottom of the liquid storage tank 15 by welding or hot melting, and is used to discharge sewage and impurities in the liquid storage tank 15 during device maintenance.

[0042] like Figure 1 As shown: a fire-resistant vent cap 8 is provided on the upper side of the liquid storage tank 15 .

[0043] Specifically, the fire-blocking vent cap 8 is connected to the top plate of the liquid storage tank 15 by means of a flange, and is used to discharge the displaced gas and nitrogen in the produced water.

[0044] like Figure 1 As shown: an overflow pipeline 9 is provided on the upper outer side of the liquid storage tank 15 .

[0045] Specifically, the overflow pipeline 9 is a safety protection measure to prevent excessive overflow of pipeline liquid.

[0046] like Figure 1 As shown: the lower part of the liquid storage tank 15 is fixedly connected to the trolley mechanism through a fixing clamp 11.

[0047] like Figure 1 As shown: the trolley mechanism includes a base plate 12, wheels 13 and handrails 18. The wheels 13 are fixedly connected to the four corners of the base plate 12, and the handrail 18 is fixedly connected to the right side of the upper end of the base plate 12.

[0048] Specifically, the bottom plate 12, the handrails 18, and the wheels 13 form a movable cart.

[0049] like Figure 1 As shown: the middle part of the upper end of the bottom plate 12 is fixedly connected to the liquid storage tank 15.

[0050] like Figure 1 As shown: the sampling pipeline 17 is provided with a sampling valve.

[0051] Specifically, the sampling pipeline 17 is installed below the liquid outlet pipeline 10 by welding or hot melting, and is used for sampling and monitoring the output water quality.

[0052] When the equipment is in use, the water to be treated enters from the liquid inlet pipeline 5 and is injected into the liquid storage tank 15 through the cyclone degasser 14. The cyclone degasser 14 can remove part of the oxygen in the liquid inlet. The flow meter 1 is used to measure the liquid inlet flow rate, and the Y-type filter 2 is used to filter impurities in the liquid inlet. The inert gas nitrogen enters from the air inlet pipeline 6 and is discharged from the small holes evenly distributed on the aeration head 16 arranged at the bottom of the liquid storage tank. The gas pressure gauge 3 is used to display the air inlet pressure, and the gas flow meter 4 is used to measure the liquid inlet flow rate. After the nitrogen is released from the aeration head 16, it moves upward, squeezing the oxygen in the liquid storage tank 15 to move upward, and finally the oxygen and excess nitrogen are discharged into the atmosphere through the flame-retardant breathable cap 8. The deoxygenated water is transported to the subsequent process through the liquid outlet pipeline 10.

[0053] The drain port 7 is used to regularly discharge the sediment at the bottom of the liquid storage tank 15, the overflow line 9 is used to discharge the excess liquid, and the sampling line 17 is used to sample the liquid in the liquid outlet line to detect the deoxygenation effect.

[0054] The bottom plate 12, the handrails 18, and the wheels 13 form a movable cart, and the liquid storage tank 15 is fixed to the bottom plate 12 by a fixing clamp 11, so as to facilitate the movement of the whole set of equipment.

[0055] Compared with existing technologies:

[0056] [1] CN202221883294.3 A sewage treatment aeration device;

[0057] During the produced water treatment process, air is introduced into the tank through an aerator, and the produced water is continuously aerated to reduce the content of anaerobic bacteria in the produced water, thereby achieving the effect of removing iron and manganese. This method mainly treats microorganisms and elements such as iron and manganese in produced water, and cannot reduce the dissolved oxygen content in produced water.

[0058] [2] CN03219467.6 Oilfield produced water treatment equipment;

[0059] The reinjected water enters the deoxygenation water tank from the top through the lifting water pump, and its bottom opening is connected to the deoxygenation water pump. The water enters the deoxygenation water pump through the bottom to increase the pressure, and is lifted to the desorption deoxygenator for deoxygenation for 3 to 10 minutes. The water from the bottom enters the circulating deoxygenation water tank, thereby removing the oxygen in the produced water. This method adds auxiliary tools such as pumps, and the deoxygenation process is complicated and difficult to maintain. It is not suitable for actual working conditions on site.

[0060] [3] CN202222723836.7 A pipeline mixer for oilfield produced water reinjection;

[0061] This method introduces produced water into the equipment box through a pipeline mixer, and adds preservatives and deoxidizers to the produced water to achieve the purpose of deoxygenating the produced water. This method deoxidizes by adding chemicals, and the deoxidizer is expensive and has low economic benefits.

[0062] [4] CN201811207136.4 A method for treating produced water from a carbon dioxide flooding oil field;

[0063] The method uses a method for treating produced water from a carbon dioxide-driven oil field, including: 1. filtering the produced water from the oil field to remove oil and suspended solids therein to obtain filtered water; 2. degassing the filtered water to remove gas therein to obtain degassed water. The present invention utilizes ceramic membrane filtration to remove oil, suspended solids, impurities, etc. in produced water, and membrane degassing technology can effectively remove carbon dioxide, oxygen, etc. in produced water. The present invention combines ceramic membrane filtration with membrane degassing technology, and has a high carbon dioxide removal rate. The obtained water can be directly used for reinjection; and can be deoxygenated at the same time. However, membrane filtration technology is relatively expensive and difficult to maintain in the later stage, which is not conducive to use in field conditions.

[0064] [5] CN201620188839.7 An oilfield produced water treatment system;

[0065] The method uses an oilfield produced water treatment system, including a sewage lift pump, the water inlet of the sewage lift pump is connected to the oilfield regulating tank, the water outlet of the sewage lift pump is connected to the water inlet of the vortex cavitation flotation machine, the water outlet of the vortex cavitation flotation machine is connected to the water inlet of the ultrasonic filter, the water outlet of the ultrasonic filter is connected to the water inlet of the sterilizer, and the water outlet of the sterilizer is connected to the reinjection water tank. First, a flocculant is added to the produced water, and after nitrogen aeration and flotation treatment by the vortex cavitation flotation device, the oil pollution and raw water in the produced water are separated, and most of the dissolved oxygen in the raw water is eliminated at the same time, but the deoxygenation agent is added, and the deoxygenator is expensive and the economic benefit is low.

[0066] Compared with the deoxygenation of produced water by using a deoxygenator, the structure of the present application can reduce the treatment cost of a ton of water by 0.5 yuan / ton on average, which has a high economic benefit. Therefore, the present invention has a good external market prospect in the domestic and foreign oil field produced water treatment process system, and the technology has the advantages of high economic benefit and strong scalability.

[0067] The above is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. It will be apparent to those skilled in the art that various modifications to these embodiments are possible, and the general principles defined in the present application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown in the present application, but will conform to the widest scope consistent with the principles and novel features applied for by the present application.

Claims

1. An oilfield produced water nitrogen aeration and deoxygenation device, characterized in that: include: A liquid storage tank (15), wherein an aeration head (16) is provided at the lower inner portion of the liquid storage tank (15), and a cyclone degasser (14) is provided at the upper inner portion of the inner cavity of the liquid storage tank (15), and the inlets of the aeration head (16) and the cyclone degasser (14) are respectively connected to an air inlet pipeline (6) and a liquid inlet pipeline (5); A liquid outlet pipeline (10), wherein the liquid outlet pipeline (10) is fixedly plugged into the lower portion of the outer side of the liquid storage tank (15), and a sampling pipeline (17) is also provided on the liquid outlet pipeline (10).

2. The oilfield produced water nitrogen aeration and deoxygenation device according to claim 1, characterized in that: The air intake pipeline (6) is also provided with a gas pressure gauge (3) and a gas flow meter (4).

3. The oilfield produced water nitrogen aeration and deoxygenation device according to claim 1, characterized in that: The liquid inlet pipeline (5) is also provided with a flow meter (1) and a Y-type filter (2), and the flow meter (1) is arranged on the outlet side of the Y-type filter (2).

4. The oilfield produced water nitrogen aeration and deoxygenation device according to claim 1, characterized in that: A sewage pipe (7) is also plugged into the lower side of the liquid storage tank (15), and a switch valve is provided on the sewage pipe (7).

5. The oilfield produced water nitrogen aeration and deoxygenation device according to claim 1, characterized in that: A fire-retardant vent cap (8) is provided on the upper side of the liquid storage tank (15).

6. The oilfield produced water aeration and deoxygenation device according to claim 1, characterized in that: An overflow pipeline (9) is provided on the upper outer side of the liquid storage tank (15).

7. The oilfield produced water aeration and deoxygenation device according to claim 1, characterized in that: The lower part of the liquid storage tank (15) is fixedly connected to the trolley mechanism via a fixing clamp (11).

8. The oilfield produced water nitrogen aeration and deoxygenation device according to claim 7, characterized in that: The trolley mechanism comprises a base plate (12), wheels (13) and a handrail (18); the wheels (13) are fixedly connected to the four corners of the base plate (12); and the handrail (18) is fixedly connected to the right side of the upper end of the base plate (12).

9. The oilfield produced water nitrogen aeration and deoxygenation device according to claim 8, characterized in that: The middle portion of the upper end of the bottom plate (12) is fixedly connected to the liquid storage tank (15).

10. The oilfield produced water nitrogen aeration and deoxygenation device according to claim 1, characterized in that: The sampling pipeline (17) is provided with a sampling valve.

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