CN209865530U - Gas-liquid separation device for defoaming gas - Google Patents

Abstract

The application provides a gas-liquid separation for gaseous defoaming device includes: the device comprises a cyclone shell, a centrifugal defoaming component and a secondary chemical defoaming component, wherein the centrifugal defoaming component and the secondary chemical defoaming component are arranged in the cyclone shell; the centrifugal defoaming component is arranged at the lower part of the rotational flow shell and comprises a rotational flow inner cylinder, a rotating blade assembly and an exhaust pipe, wherein the rotating blade assembly is arranged in the rotational flow inner cylinder, and the rotating blade assembly is sleeved on the outer side of the exhaust pipe; the secondary chemical defoaming component is arranged on the upper part of the rotational flow shell and comprises a defoaming net arranged above the rotational flow inner cylinder in the device and a corrugated plate arranged above the defoaming net. Compared with the existing chemical defoaming method, the method has the advantages that the operation cost is greatly reduced, meanwhile, the gas-liquid two-phase pre-separation process can be realized, and the generation of secondary foam can be effectively reduced.

Description

Gas-liquid separation device for defoaming gas

Technical Field

The application relates to the technical field of multi-phase flow separation, in particular to a defoaming operation and a gas-liquid pre-separation process used in a natural gas foam drainage gas production process.

Background

The existing foam drainage gas production process is a better technology for removing accumulated liquid at the bottom of a well in the middle and later stages of natural gas (including shale gas) production. However, before the natural gas enters the gas transmission pipeline, if a large amount of stable foam carried by the natural gas is not removed in time, certain damage can be caused to pipeline conveying equipment and metering instruments, and meanwhile, the liquid removal effect of the gas-liquid separation equipment is also seriously influenced, so that the safe operation of the gas transmission system is further influenced.

A chemical defoaming method is usually adopted in a first-line station to implement defoaming operation, namely, a skid-mounted injection device is used for regularly putting special defoaming agent liquid or a defoaming rod into a gas pipeline or a tank specially used for defoaming to defoam. Although the defoaming agent has a certain defoaming effect, the universality is not strong, different types of foaming agents and defoaming agents are required to be used for gas wells in different areas, and the early investment cost is correspondingly increased. In addition, the consumption of defoaming agent is bigger, and the defoaming agent quantity that drops into in the actual operation reaches 2 ~ 4 times of theoretical calculation value, only can ensure like this that the defoaming agent fully contacts with the foam, and then reaches the purpose of quick defoaming. The price of the defoaming agent in the existing market is about 3 ten thousand yuan/ton, which leads to the great increase of the operation cost of defoaming operation, and the price is an important technical subject which is urgently and thoroughly desired to be solved by the natural gas production management department.

Meanwhile, the natural gas after the defoaming operation is completed usually enters corresponding gas-liquid separation equipment to remove liquid drop impurities, so that the safe and reliable operation of core equipment such as a compressor unit, a metering instrument and the like in a natural gas long-distance pipeline and a gathering and transportation system is ensured. On site, the natural gas is subjected to deep gas-liquid separation mainly through equipment such as a gas-liquid coalescing filter and the like, and the filtering precision of the coalescing filter is high (usually 0.3 mu m), so the filtering requirement of the coalescing filter element can be met only by the small aperture of the filter material of the coalescing filter element. When the concentration of the liquid contained in the gas is high or the upstream defoaming is incomplete (including the generation of secondary foam), a large amount of liquid drop impurities (especially foam) carried in the gas can be intercepted inside the filter element and block pores inside the filter material, so that the pressure drop of the filter element is rapidly increased, the operation of the filter element must be suspended and replaced in time, and the operation cost is further increased by frequently replacing the filter element.

SUMMERY OF THE UTILITY MODEL

The application provides a gas-liquid separation device for defoaming of gas to at least solve the problem that natural gas carries a large amount of foams among the prior art.

According to an aspect of the present application, there is provided a gas-liquid separation device for defoaming gas, including: the device comprises a cyclone shell 3, a centrifugal defoaming component and a secondary chemical defoaming component which are arranged in the cyclone shell 3; the centrifugal defoaming component is arranged at the lower part of the rotational flow shell 3 and comprises a rotational flow inner cylinder 4, a rotating blade assembly 5 arranged in the rotational flow inner cylinder 4 and an exhaust pipe 7, and the rotating blade assembly 5 is sleeved outside the exhaust pipe 7; the secondary chemical defoaming component is arranged at the upper part of the rotational flow shell 3 and comprises a defoaming net 10 arranged above the rotational flow inner cylinder 4 in the device and a corrugated plate 11 arranged above the defoaming net 10.

In one embodiment, the centrifugal part further comprises a tangential inlet pipeline 2, which is inclined downwards in a horizontal direction by 10-60 degrees, so that the airflow obtains an initial downward speed, and the purpose is to quickly complete the impacting and centrifugal defoaming process of the airflow.

In one embodiment, the swirl inner barrel 4 is a multi-layer structure and comprises an inner barrel 41 and an outer barrel 3.

In one embodiment, a porous structure is arranged on the surface of the inner-layer cylinder 41, the outer-layer cylinder 3 is of a solid structure, and atomizing nozzles are uniformly arranged at a position 20-50 mm away from the inner side wall surface of the inner-layer cylinder 41 along the circumferential direction through a water supply pipeline. The atomizing nozzles are arranged for the purpose of: on the one hand, residual foam on the wall can be removed, and on the other hand, injected water drops can destroy the stability of the foam by reducing the concentration of the foaming agent in the foam.

In one embodiment, the defoaming net 10 is a multi-layer wire mesh structure, the mesh aperture increases from bottom to top, and the surface of the wire mesh is subjected to super-hydrophobic treatment. The structure of the defoaming net can uniformly distribute airflow, simultaneously utilize the extrusion effect of the meshes to defoam, and has certain coalescence capability on small liquid drops. Further, the wire mesh structure may be replaced with a porous foam structure, such as porous nickel foam, etc., in which the pores are three-dimensional pores.

In one embodiment, the corrugated plate 11 is composed of a plurality of corrugated blades 110 arranged in parallel at intervals and an airflow channel 111 formed by the corrugated blades, a liquid discharge chamber 12 and a fixed housing 13, wherein the front and rear parts of the corrugated blades 110 are distinguished by the presence or absence of a hydrophobic hook 113, the rear half part of the corrugated blade 110 is provided with the hydrophobic hook 113, and the front half part is not provided.

In one embodiment, the surface of each of the blades 110 of the corrugated plate 11 is prepared as a super-hydrophobic surface through a modification treatment, and the super-hydrophobic surface can further achieve defoaming and separation of liquid entrained in natural gas.

The existing natural gas liquid defoamer usually needs to consume a large amount of defoamer to meet the requirement of defoaming operation, and the price of the defoamer in the current market is as high as about 3 ten thousand yuan per ton. Meanwhile, a defoaming agent with universality is not researched, and a certain amount of capital must be invested in the early stage to research a proper defoaming agent, so that the investment cost of the defoaming process is further increased.

Compared with the existing defoaming technology, the application reasonably utilizes physical defoaming methods such as centrifugal force, inertial impact and the like and chemical defoaming mechanism capable of defoaming on the hydrophobic surface to realize quick defoaming, and simultaneously, gas-liquid pre-separation can be carried out. The method not only can greatly reduce the cost of defoaming operation, but also can effectively inhibit the generation of secondary foam through the effective separation of gas phase and liquid phase, thereby effectively improving the gas-liquid separation effect of the coalescence filter element and prolonging the service life of the coalescence filter element.

In order to meet the standard of defoaming operation, the existing natural body liquid defoamer is generally used in a first-line station by continuously injecting defoamer. And when the operating time is longer, mix impurity easily in the defoaming agent pipeline, and the nozzle of dosing then can make its spun defoaming agent dosage reduce to some extent because of its inside jam that takes place to lead to the defoaming incomplete, a small amount of foam then can get into downstream equipment through exhaust pipe, and remaining surface active substance leads to the foam regeneration phenomenon easily in the place that pipeline resistance is big, not only the hydrops phenomenon is serious but also causes the pipeline to corrode easily, thereby influences gas transmission safety.

Compared with the existing natural gas liquid defoamer, the defoaming and gas-liquid separation process is realized simultaneously for many times by skillfully utilizing a physical defoaming method and a chemical defoaming mechanism, so that the bubble breaking rate and the gas-liquid separation efficiency can be improved, the generation of secondary foam can be effectively prevented, and the phenomenon of accumulated liquid in a pipeline is reduced.

The existing chemical defoaming method is characterized in that a defoaming agent and a surfactant are subjected to chemical reaction, so that the stability of foam is damaged and the foam is collapsed, the repeated foaming capacity of a foaming agent is influenced, and the recycling of a foam base liquid is difficult to realize.

Compared with the existing chemical defoaming method, the application skillfully utilizes a plurality of defoaming mechanisms to achieve the effect of the defoaming agent, namely, the liquid discharge speed of the foam surface liquid film is accelerated by defoaming methods such as centrifugal force, inertia impact and super-hydrophobic surface to destroy the stability of the foam surface liquid film and force the foam to be quickly destroyed. In addition, other surface active substances are not added, the separated foaming base liquid can be recycled, and the investment cost is further reduced.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of the present application.

FIG. 2 is a schematic view of a tangential inlet line.

Fig. 3 is a schematic view of a rotating vane assembly.

Fig. 4 is a schematic view of a cyclone cartridge.

Fig. 5 is a cross-sectional view of a cyclone cartridge.

Figure 6 is a schematic diagram of a graded pore size defoaming net.

Figure 7 is a corrugated board installation schematic.

Figure 8 is an isometric illustration of a corrugated sheet.

Reference numerals:

1. gas production pipe;

2. a tangential inlet line;

3. a cyclone housing;

4. a rotational flow inner cylinder;

5. a rotating blade assembly;

51. a rotating blade;

52. a shaft sleeve;

53. a flange;

6. a liquid collection cavity;

7. an exhaust pipe;

8. a liquid discharge port;

9. a pod;

10. a defoaming net;

101. the aperture of the silk screen;

11. a corrugated plate;

12. a liquid discharge cavity;

13. an outlet line;

14. fixing the housing;

110. a corrugated blade;

111. an air flow channel;

112. an airflow outlet;

113. a water-repellent hook;

15. separating the partition plate.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In order to solve the problems in the prior art, the present application provides a gas-liquid separation device for defoaming gas, as shown in fig. 1, the gas-liquid separation device mainly comprises a cyclone casing 3, a centrifugal defoaming component and a secondary chemical defoaming component, the centrifugal defoaming component is arranged in the lower part of the cyclone casing 3, and the secondary chemical defoaming component is arranged in the upper part of the cyclone casing 3.

The centrifugal defoaming component mainly comprises a rotating vane assembly 5 and an exhaust pipe 7 which are arranged in the cyclone inner cylinder 4, and the rotating vane assembly 5 is sleeved outside the exhaust pipe 7.

The secondary chemical defoaming component is arranged at the upper part of the rotational flow shell 3 and comprises a defoaming net 10 arranged above the rotational flow inner cylinder 4 in the device and a corrugated plate 11 arranged above the defoaming net 10.

The centrifugal defoaming unit further comprises: and the tangential inlet pipeline 2 is horizontally and obliquely arranged downwards and is used for introducing natural gas into the rotational flow inner barrel 4.

In one embodiment, as shown in FIG. 2, the angle of inclination of the tangential inlet pipe 2 is in the range of 10 to 60 degrees. The purpose of the inlet structure design is to make the air flow have downward initial speed, so that the air flow can quickly complete the processes of shearing, impacting and centrifugal defoaming, and simultaneously can accelerate the liquid drainage speed of the liquid film on the wall surface of the cylinder body.

In one embodiment, as shown in fig. 1, the cyclone housing 3 may be divided into an upper part and a lower part by a separation partition 15.

As shown in fig. 3, the rotating blade assembly 5 includes: the shaft sleeve 52 and a plurality of rotating blades 51 uniformly fixed on the shaft sleeve are sleeved with the outer side of the exhaust pipe 7 through the shaft sleeve 52, and the exhaust pipe 7 is fixed with the separating partition 15 of the upper and lower cavities through a flange 53. During the concrete implementation, when high-speed air current got into whirl inner tube 4 along tangential inlet line 2, thereby drive it and take place to rotate with rotating vane subassembly 5 bumps, can reduce the momentum loss that inertial collision caused, and rotating vane's rotation can also force the air current to be high-speed rotatory flow, makes its centrifugal force that receives different through the two-phase great density difference of gas-liquid, makes the liquid film flowing back of foam surface accelerate, and then destroys the stability of foam and make its quick breakage.

In one embodiment, the angle between the rotating blade assembly 5 and the outer hub of the exhaust pipe 7 is 30 to 90 degrees. The shape of the rotary blade may be an arc line type, but the present application is not limited thereto. In addition, specific parameters such as the bending angle of the rotating blades, the number of the rotating blades and the length of the rotating blades can be optimized according to actual working conditions.

As shown in fig. 4 and 5, the surface of the swirl inner cylinder 4 is provided with a porous structure, the pore size of the porous structure can be optimized according to the size of the actual foam, and the shape of the pores can be a common pore type such as a diamond shape, a circle shape, and the like, but the application is not limited thereto.

In one embodiment, the opening direction is horizontal or inclined downwards. Utilize the hole to the extrusion effect that the foam produced and make its internal and external pressure difference increase until taking place the defoaming mechanism of destroying, can realize further defoaming, the liquid of catching by its wall can pass between the inner wall that porous structure got into whirl casing 3 and the outer wall of whirl inner tube 4 simultaneously to form the liquid film at the inner wall of whirl casing 3 and discharge downwards, can effectively reduce the secondary of liquid drop and smuggle secretly.

In addition, in one embodiment, this application can set up a plurality of atomizing nozzle, and atomizing nozzle can set up in the inside wall face 20 ~ 50mm department apart from whirl inner tube 4, presses close to the baffle of upper and lower cavity simultaneously. Atomized water droplets are injected into the atomizing nozzle through a water supply pipeline (not shown in the figure), on one hand, residual foams on the wall surface, especially crystals of surface active substances, can be removed; on the other hand, the injected water droplets can reduce the concentration of the blowing agent in the foam, thereby destabilizing the foam (increasing the surface tension) and shortening the collapse time thereof. The liquid adding amount of the atomizing nozzle can be determined according to the separating capacity of the gas-liquid separating device, and generally cannot exceed 90% of the maximum allowable gas liquid content.

Specifically, the cyclone housing 3 is a solid structure, and the surface thereof is subjected to anticorrosion and oleophobic and hydrophobic treatment to accelerate liquid discharge.

During specific implementation, parameters such as the pipe diameter and the length of the exhaust pipe need to be selected according to the inner diameter of the whole equipment cylinder body so as to better adjust the air flow speed, realize quick defoaming and improve the gas-liquid separation efficiency.

As shown in fig. 6, the defoaming net 10 is a 5-15-layer net structure, the nets with different pore sizes are fixed together, so that the large pressure difference generated by the extrusion effect of small pores and the super-hydrophobic surface of the small pores can be utilized to realize defoaming while the air flow is uniformly distributed, and the structure has certain coalescence capability on small liquid droplets. In one embodiment, the screen structure with the gradient arrangement of the pore diameters from bottom to top (namely the pore diameters are sequentially increased) has small resistance, and the inside of the screen structure is not easy to block; the surface of the silk screen is treated with super-hydrophobic treatment, which can accelerate the liquid drainage speed of the liquid film on the surface of the foam, so that the liquid film can be quickly broken and drained through the liquid guide pipe 102.

As shown in fig. 7 and 8, the corrugated plate 11 is composed of a plurality of corrugated blades 110, a drainage chamber 12 and a fixed casing 14, which are arranged in parallel and spaced apart from each other. The drainage chamber 12 is disposed below the corrugated plate 11. The adjacent corrugated blades 110 form gas flow channels 111, and the gas passing through the defoaming net 10 passes through the gas flow channels 111 to be deeply defoamed by inertial impact and a super-hydrophobic coating on the surface. The liquid droplets intercepted by the corrugated blades 110 form a thin liquid film on the surface thereof, and flow downwards into the liquid discharge chamber 12 under the action of gravity.

In one embodiment, as shown in fig. 8, the rear part of the corrugated blade 110 is provided with a hydrophobic hook 113 to accelerate liquid drainage, thereby effectively reducing the secondary entrainment of liquid droplets; meanwhile, the surface of each blade is prepared into a super-hydrophobic surface through modification treatment, and when bubbles collide with the surface of the blade, hydrophobic solid particles of the surface coating attract hydrophobic ends of the surfactant to enable the hydrophobic ends to generate hydrophilicity and enter a water phase, so that the defoaming effect is achieved. The corrugated plate can be triangular, trapezoidal, arc-shaped and the like, and the material of the corrugated plate is not limited to common materials such as stainless steel, glass fiber reinforced plastic, polypropylene and the like.

The working flow of the gas-liquid separation device is as follows: high-pressure natural gas firstly enters a rotational flow inner cylinder 4 from a gas production pipe 1 through a tangential inlet pipeline 2, airflow forms downward high-speed rotational flow under the flow guiding action of a rotating vane assembly 5, and a centrifugal field is formed inside the rotational flow inner cylinder 4. Because the gas phase and the liquid phase have larger density difference and are subjected to different centrifugal forces, the heavier liquid phase is thrown to the inner side wall surface of the rotational flow inner cylinder 4, and the light gas phase continuously moves to the center of the cylinder body to form a gas core.

The existence of centrifugal field makes the foam receive uneven internal and external atress, and the liquid film on its surface receives centrifugal force great and impels the flowing back speed to accelerate, and local surface liquid film attenuation, and the bubble inside the foam is because inside and outside pressure differential is bigger and bigger, and gas constantly permeates the liquid film and outwards diffuses, makes the stability of foam suffer serious destruction, consequently can reach the purpose of defoaming.

In addition, the open pore structure on the surface of the rotational flow inner cylinder 4 can realize further defoaming through inertial impact, and can intercept partial small foams, surface active substances and other solid impurities, so that the phenomenon of secondary foaming can be effectively inhibited.

Then, the gas from the exhaust pipe 7 passes through the defoaming net 10, so that the gas flow distribution is uniform, and the secondary defoaming can be performed by using multiple layers of defoaming nets, and meanwhile, the defoaming nets have a certain coalescence effect on small liquid drops.

Finally, the airflow enters the corrugated plate 11, deep defoaming is carried out by utilizing inertial impact and the super-hydrophobic coating on the surface, large liquid drops carried in the gas can be separated, and the intercepted liquid drops can form a thin liquid film on the surface of the blade and flow downwards into the liquid discharge cavity 12 under the action of gravity. While the fine droplet impurities are removed with the gas through outlet line 13 into the downstream coalescing filter. The application recommends defoaming operation and gas-liquid pre-separation process suitable for foam drainage gas production process, utilizes various defoaming methods to accelerate the liquid discharge speed of the foam surface liquid film so as to destroy the stability of the foam surface liquid film, promotes the foam to be rapidly destroyed and simultaneously carries out the gas-liquid pre-separation process, realizes the effective separation of gas and liquid phases, and further can effectively suppress the phenomenon of 'secondary foaming'.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the hardware + program class embodiment, since it is substantially similar to the method embodiment, the description is simple, and the relevant points can be referred to the partial description of the method embodiment.

The foregoing description has been directed to specific embodiments of this disclosure. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims may be performed in a different order than in the embodiments and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may also be possible or may be advantageous.

Although the present application provides method steps as described in an embodiment or flowchart, additional or fewer steps may be included based on conventional or non-inventive efforts. The order of steps recited in the embodiments is merely one manner of performing the steps in a multitude of orders and does not represent the only order of execution. When an actual apparatus or client product executes, it may execute sequentially or in parallel (e.g., in the context of parallel processors or multi-threaded processing) according to the embodiments or methods shown in the figures.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of an embodiment of the specification. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

The principle and the implementation mode of the present application are explained by applying specific embodiments in the present application, and the description of the above embodiments is only used to help understanding the method and the core idea of the present application; meanwhile, for a person skilled in the art, according to the idea of the present application, the specific embodiments and the application range may be changed. In view of the above, the description should not be taken as limiting the application.

Claims (12)

1. A gas-liquid separation device for defoaming gas, comprising: the defoaming device comprises a cyclone shell (3), a centrifugal defoaming component and a secondary chemical defoaming component, wherein the centrifugal defoaming component and the secondary chemical defoaming component are arranged in the cyclone shell (3);

the centrifugal defoaming component is arranged at the lower part of the rotational flow shell (3) and comprises a rotational flow inner cylinder (4), a rotating blade assembly (5) arranged in the rotational flow inner cylinder (4) and an exhaust pipe (7), and the rotating blade assembly (5) is sleeved outside the exhaust pipe (7);

the secondary chemical defoaming component is arranged on the upper part of the rotational flow shell (3) and comprises a defoaming net (10) arranged above the rotational flow inner cylinder (4) in the device and a corrugated plate (11) arranged above the defoaming net (10).

2. The gas-liquid separation device according to claim 1, wherein the centrifugal defoaming unit further comprises: and the tangential inlet pipeline (2) is horizontally and obliquely downwards arranged and is used for introducing natural gas into the rotational flow inner cylinder (4).

3. The gas-liquid separation device according to claim 2, wherein the tangential inlet pipe (2) has an inclination angle in the range of 10 to 60 degrees.

4. The gas-liquid separation device according to claim 1, wherein the side wall of the cyclone inner cylinder (4) is provided with a plurality of holes, and the plurality of holes are horizontally or obliquely downward.

5. A gas-liquid separation device according to claim 1, wherein the cyclone housing (3) is divided into upper and lower portions, and is partitioned by a partition plate (15).

6. The gas-liquid separation device according to claim 5, wherein a plurality of atomizing nozzles are uniformly arranged along the circumferential direction at a distance of 20-50 mm from the inner side wall surface of the cyclone inner cylinder (4), and the atomizing nozzles are in contact with the lower surface of the separation partition plate (15).

7. The gas-liquid separation device according to claim 1, wherein the defoaming net (10) has a multi-layer wire mesh or porous foam structure, the pore size of each layer of wire mesh or porous foam increases from bottom to top, and the surfaces of the multi-layer wire mesh and porous foam are superhydrophobic surfaces.

8. The gas-liquid separation device according to claim 1, wherein the corrugated plate (11) includes: the device comprises a plurality of corrugated blades (110) distributed at intervals, a fixed shell (14) and a liquid discharge cavity (12) arranged below the corrugated plates (11).

9. The gas-liquid separation device according to claim 8, wherein a rear portion of the corrugated blade (110) is provided with a hydrophobic hook (113).

10. The gas-liquid separation device according to claim 8, wherein a surface of each of the corrugated blades (110) of the corrugated plate (11) is a superhydrophobic surface by a modification treatment.

11. The gas-liquid separation device according to claim 1, wherein the rotating vane assembly (5) comprises: the rotary vane comprises a shaft sleeve (52) and a plurality of rotary vanes (51) uniformly and fixedly arranged on the shaft sleeve (52).

12. The gas-liquid separation device according to claim 11, wherein an angle between the rotating blade (51) and an outer hub of the exhaust pipe (7) is 30-90 degrees.