CN112779047A

CN112779047A - Electrode plate and electric desalting tank

Info

Publication number: CN112779047A
Application number: CN201911083543.3A
Authority: CN
Inventors: 张艳玲; 韩磊; 许伟伟; 屈定荣; 兰正贵; 牛鲁娜
Original assignee: China Petroleum and Chemical Corp; Sinopec Qingdao Safety Engineering Institute
Current assignee: China Petroleum and Chemical Corp; Sinopec Safety Engineering Research Institute Co Ltd
Priority date: 2019-11-07
Filing date: 2019-11-07
Publication date: 2021-05-11
Anticipated expiration: 2039-11-07
Also published as: CN112779047B

Abstract

The invention relates to the technical field of crude oil electric desalting, and discloses an electrode plate and an electric desalting tank. The electrode plate comprises a plurality of electrode rods and a plurality of supporting beam bodies, wherein the supporting beam bodies are arranged at intervals to form electrode rod setting intervals between the adjacent supporting beam bodies, the electrode rods are arranged in the electrode rod setting intervals at intervals in the extending direction of the supporting beam bodies, and the electrode rods are arranged at intervals along the wave-shaped curve. The wave-shaped inclined planes of the electrode rods arranged in the wave shape are beneficial to rolling of large liquid drops, the oil-water separation effect is enhanced, and the electrode rods arranged in the wave shape can keep the stability of a weak electric field under the condition of high and low fluctuation of an oil-water layer interface, so that the desalting and dewatering effect of crude oil is improved.

Description

Electrode plate and electric desalting tank

Technical Field

The invention relates to the technical field of crude oil electric desalting, in particular to an electrode plate and an electric desalting tank.

Background

The crude oil produced in the formation inevitably contains a certain amount of salts and water due to the source and environment of the crude oil. In addition, the crude oil also carries small amounts of water during its production, transportation and processing. Salts and water contained in crude oil not only cause damage to oil plants but also adversely affect the processing of crude oil, and therefore, it is necessary to desalt and dewater crude oil.

The core equipment of the crude oil electric desalting device is an electric desalting tank, and electrodes are arranged in the electric desalting tank to form an electric field, so that the crude oil is subjected to the action of a high-voltage electric field and a demulsifier to gradually agglomerate micro liquid drops into larger water drops, and the larger water drops are settled and separated from the crude oil under the action of gravity. The most common electrode forms at present are a horizontal type, a vertical suspension type and a squirrel cage type, and the electrode plates are generally grid-shaped.

In practice, the horizontal electrode plates only have an electric field between the electrode plates, the actual retention time of the crude oil in the electric field region is short, and particularly for the electric desalting tank with a two-layer electrode plate structure, the stability of a weak electric field is easily influenced under the condition that the height of an oil-water interface fluctuates up and down, and the desalting and dewatering of raw materials are unfavorable. The electrode plates arranged in a vertical suspension way can obtain larger electric field capacity, but the alternating current and direct current desalting equipment using the arrangement has the defects of complex structure, easy failure of the quality of rectifying equipment and the like. The squirrel-cage electrode has good desalting and dewatering effects, but has large volume, and high construction cost and energy consumption.

Disclosure of Invention

An object of the present invention is to provide an electrode plate capable of improving efficiency of electric desalting when it is disposed in an electric desalting tank, and reducing construction costs and energy consumption.

In order to achieve the above object, in a first aspect, the present invention provides an electrode plate comprising a plurality of electrode rods and a plurality of support beam bodies, wherein the plurality of support beam bodies are arranged at intervals to form an electrode rod arrangement interval between adjacent support beam bodies, wherein the plurality of electrode rods are arranged at intervals in the electrode rod arrangement interval in an extending direction of the support beam bodies, and the plurality of electrode rods are arranged at intervals along a wave-shaped curve.

According to the technical scheme, the plurality of electrode rods are arranged in the electrode rod arrangement intervals at intervals in the extending direction of the supporting beam body and are arranged at intervals along the wave-shaped curve, namely, the plurality of electrode rods are integrally in the wave-shaped curve, and when at least two electrode plates are arranged in the electric desalting tank, for example, the plurality of electrode rods of each electrode plate are arranged in a wave shape. For example, the lower electrode plate is connected with an alternating current power supply, the upper electrode plate is grounded, and an oil-water layer interface at the bottom in the electric desalting tank is also used as a grounded electrode plate, so that a strong electric field is formed between the two electrode plates, and a weak electric field is formed between the lower electrode plate and the oil-water layer interface. Therefore, the oil-water mixture enters the electric desalting tank from the bottom of the electric desalting tank, rapidly rises through an oil-water layer interface, enters a weak electric field area, and then enters a strong electric field area through a lower electrode plate. Under the action of an electric field, salt-containing small droplets in the oil-water mixture are aggregated into large droplets, the large droplets are settled out from the crude oil and enter a continuous water phase at the bottom of the electric desalting tank, salt-containing sewage can be discharged through a water outlet at the bottom of the tank, and the dehydrated crude oil flows out from an upper collector of the electric desalting tank. When an oil-water mixture passes through the electrode plates from bottom to top, the electrode rods are arranged at intervals along the wave-shaped curve, so that the effective contact area between the liquid drops and the electrode rods is increased, the flow direction of the oil-water mixture is consistent with the direction of an electric field in a strong electric field area, the electrostatic acting force between the liquid drops is increased, the liquid drops are charged after contacting the electrode rods, the dipole coalescence and electrophoretic coalescence processes between the liquid drops are enhanced, the wave-shaped inclined planes of the electrode rods arranged in a wave shape are favorable for rolling of large liquid drops, the oil-water separation effect is enhanced, the large liquid drops can form a water film at the intervals between the electrode rods, the water film can enhance the liquid drop-interface coalescence effect in the electrocoagulation process, and in addition, under the condition of high and low fluctuation of an oil-water layer interface, the electrode rods arranged in a wave shape can keep the stability of a weak electric field, this is advantageous for improving the desalting and dewatering effect of the crude oil.

Further, the electrode rods are arranged in parallel, and two ends of each electrode rod are respectively connected to the support beam bodies corresponding to the respective ends.

Further, the support beam body is wave-shaped.

Further, the wavy extending tracks of the supporting beam bodies are the same.

Further, the wavy upper surface of the support beam body is formed by the equation y-sin (x), and the wavy lower surface of the support beam body is formed by the equation y-sin (x) -0.2, wherein 0< x <2 pi.

Further, the plurality of electrode rods are arranged at equal intervals along a curve y ═ sin (x) -0.1, wherein 0< x <2 pi.

Further, a plurality of the support beam bodies are conductive beam bodies.

In a second aspect, the invention provides an electric desalting tank, which comprises a tank body with a crude oil inlet, a water outlet and a crude oil outlet, wherein a plurality of electrode plates are arranged in the tank body at intervals in the height direction, and the electrode plates are wave-shaped electrode plates.

As the electrode plates are wavy electrode plates, the lower electrode plate is connected with an alternating current power supply, the upper electrode plate is grounded, and the oil-water layer interface at the bottom in the electric desalting tank is also used as a grounded electrode plate, so that a strong electric field is formed between the two electrode plates, and a weak electric field is formed between the lower electrode plate and the oil-water layer interface. Therefore, the oil-water mixture enters the electric desalting tank from the bottom of the electric desalting tank, rapidly rises through an oil-water layer interface, enters a weak electric field area, and then enters a strong electric field area through a lower electrode plate. Under the action of an electric field, salt-containing small droplets in the oil-water mixture are aggregated into large droplets, the large droplets are settled out from the crude oil and enter a continuous water phase at the bottom of the electric desalting tank, salt-containing sewage can be discharged through a water outlet at the bottom of the tank, and the dehydrated crude oil flows out from an upper collector of the electric desalting tank. When the oil-water mixture passes through the electrode plates from bottom to top, the effective contact area between the liquid drops and the electrode plates is increased because the plurality of electrode plates are arranged at intervals along the wave-shaped curve, the flowing direction of the oil-water mixture is consistent with the direction of an electric field in a strong electric field area, the electrostatic acting force between the liquid drops is increased, the electrode plates are bare electrodes, the liquid drops are charged after contacting the electrode plates, the dipole coalescence and electrophoretic coalescence processes between the liquid drops are enhanced, the wave-shaped inclined planes of the wave-shaped electrode plates are beneficial to rolling of large liquid drops, the oil-water separation effect is enhanced, the large liquid drops can form water films at the intervals penetrating through the thickness of the electrode plates, the water films can enhance the liquid drop-interface coalescence effect in the electrocoagulation process, and in addition, under the condition of high and low fluctuation of the oil-water layer interface, the wave-shaped electrode, this is advantageous for improving the desalting and dewatering effect of the crude oil.

Further, the height of the electrode plates and the distance between the adjacent electrode plates can be adjusted.

Further, the electrode plate is the electrode plate described in any of the above first aspects.

Drawings

Fig. 1 is a schematic perspective view of an electrode plate according to an embodiment of the present invention, showing two such electrode plates stacked in a height direction;

FIG. 2 is a schematic diagram of a top view of an electrode plate according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a side view of an electrode plate according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a simple structure of an electric desalting tank according to an embodiment of the present invention.

Description of the reference numerals

1-electrode bar, 2-supporting beam body, 3-interval, 4-wave upper surface, 5-wave lower surface, 6-crude oil inlet, 7-water outlet, 8-crude oil outlet, 9-tank body, 10-electrode plate, 11-distributor, 12-hanger, 13-transformer and 14-upper collector.

Detailed Description

In a first aspect, as shown in fig. 1 to 3, the present invention provides an electrode plate comprising a plurality of electrode rods 1 and a plurality of support beam bodies 2, wherein the plurality of support beam bodies 2 are arranged at intervals to form electrode rod arrangement intervals 3 between adjacent support beam bodies 2, that is, the plurality of support beam bodies 2, for example, two support beam bodies 2, are arranged at intervals side by side, wherein the plurality of electrode rods 1 are arranged at intervals in the electrode rod arrangement intervals 3 in the extending direction of the support beam bodies 2, and the plurality of electrode rods 1 are arranged at intervals along a wave-shaped curve.

In this embodiment, since the plurality of electrode rods 1 are arranged at intervals in the electrode rod arrangement interval 3 in the extending direction of the support beam body 2, and the plurality of electrode rods 1 are arranged at intervals along the wave-shaped curve, that is, the plurality of electrode rods 1 are entirely in the wave-shaped curve, when at least two such electrode plates are arranged in the electric desalting tank, for example, the plurality of electrode rods of each electrode plate are arranged in the wave-shaped curve. For example, the lower electrode plate is connected with an alternating current power supply, the upper electrode plate is grounded, and an oil-water layer interface at the bottom in the electric desalting tank is also used as a grounded electrode plate, so that a strong electric field is formed between the two electrode plates, and a weak electric field is formed between the lower electrode plate and the oil-water layer interface. Therefore, the oil-water mixture enters the electric desalting tank from the bottom of the electric desalting tank, rapidly rises through an oil-water layer interface, enters a weak electric field area, and then enters a strong electric field area through a lower electrode plate. Under the action of an electric field, salt-containing small droplets in the oil-water mixture are aggregated into large droplets, the large droplets are settled out from the crude oil and enter a continuous water phase at the bottom of the electric desalting tank, salt-containing sewage can be discharged through a water outlet at the bottom of the tank, and the dehydrated crude oil flows out from an upper collector of the electric desalting tank. When an oil-water mixture passes through the electrode plates from bottom to top, the electrode rods are arranged at intervals along the wave-shaped curve, so that the effective contact area between the liquid drops and the electrode rods is increased, the flow direction of the oil-water mixture is consistent with the direction of an electric field in a strong electric field area, the electrostatic acting force between the liquid drops is increased, the liquid drops are charged after contacting the electrode rods, the dipole coalescence and electrophoretic coalescence processes between the liquid drops are enhanced, the wave-shaped inclined planes of the electrode rods arranged in a wave shape are favorable for rolling of large liquid drops, the oil-water separation effect is enhanced, the large liquid drops can form a water film at the intervals between the electrode rods, the water film can enhance the liquid drop-interface coalescence effect in the electrocoagulation process, and in addition, under the condition of high and low fluctuation of an oil-water layer interface, the electrode rods arranged in a wave shape can keep the stability of a weak electric field, this is advantageous for improving the desalting and dewatering effect of the crude oil.

In the electrode plate of the present invention, in an embodiment, each supporting beam body 2 may be a vertical plate, for example, two vertical plates are oppositely arranged at intervals, and a plurality of electrode rods 1 are arranged between two vertical plates along the wave shape at intervals, for example, two ends of each electrode rod 1 are respectively connected to the vertical plate corresponding to the respective end. Alternatively, in another embodiment, the support beam body 2 is wave-shaped to form a wave beam, such as the structure illustrated in fig. 1 to 3, which can significantly reduce the cost and make the electrode plate lighter, for example, two wave beams are spaced apart, and a plurality of electrode rods are spaced apart along the wave extension direction of the two wave beams, so that a plurality of electrode rods 1 are spaced apart along the wave curve.

In addition, in the electrode plate of the present invention, the plurality of electrode rods 1 may have a plurality of arrangements, for example, some of the plurality of electrode rods may be parallel to each other, some of the plurality of electrode rods may be inclined to each other, or, as shown in fig. 2, the plurality of electrode rods 1 may be parallel to each other, and both ends of each electrode rod 1 may be respectively connected to the support beam bodies 2 corresponding to the respective ends, so that the connection stability of each electrode rod 1 may be improved. It should be understood that, in another mode, both ends of the first electrode rod and the last electrode rod of the plurality of electrode rods 1 may be respectively connected to the support beam bodies 2 corresponding to the respective ends, an intermediate beam body may be connected between the first electrode rod and the last electrode rod, and the other electrode rods between the first electrode rod and the last electrode rod may be disposed on the intermediate beam body, preferably, the intermediate beam body is a wave-shaped beam body. The number of the middle beam bodies may be one, and preferably, both ends of one middle beam body may be connected to the middle portions of the leading electrode rod and the trailing electrode rod, respectively. Of course, the number of the middle beam bodies can be two, and the two middle beam bodies are arranged at intervals and are respectively connected to two ends of the head electrode rod and the tail electrode rod. The intermediate beam body can be an insulator or an electrode rod.

In addition, when the support beam body 2 is in a wave shape to be formed into a wave beam, the wave extension trajectories of a plurality of wave beams, for example, two wave beams shown in fig. 2, may be the same, so that it is convenient to manufacture and connect the electrode rods by positioning the two wave beams having the same trajectories at intervals and connecting the plurality of electrode rods. Of course, the wave extension trajectories of a plurality of wave beams, such as the two wave beams shown in fig. 2, may alternatively be different.

In addition, the plurality of electrode rods can be arranged undulating with any desired curvature, and the undulating beam can also extend with any desired undulating curvature. For example, as shown in fig. 3, the wavy upper surface 4 of the support beam body 2 is formed by the equation y ═ sin (x), where 0< x <2 pi, and the wavy lower surface 5 of the support beam body 2 is formed by the equation y ═ sin (x) -0.2, where 0< x <2 pi. In this way, it is possible to have a thicker thickness at the valleys and valleys of the waves, thereby maintaining the self-strength of the support beam body 2 while making the electrode plate as lightweight as possible.

Of course, it will be appreciated that the undulating upper surface 4 and the undulating lower surface 5 of the support beam body 2 may have the same curvature, i.e., may be formed by the same equation as set forth above.

In addition, as shown in fig. 1 and 2, the plurality of electrode rods 1 are arranged at equal intervals along a curve y ═ sin (x) -0.1, where 0< x <2 pi.

In addition, in the electrode plate of the invention, the plurality of supporting beam bodies 2 can be conductive beam bodies, so that each electrode rod can be electrified only by electrifying the supporting beam bodies 2.

Of course, the plurality of support beams 2 may be insulating beams, and it is necessary to supply power to each electrode rod when power is supplied.

In a second aspect, the present invention provides an electric desalting tank, as shown in fig. 4, which comprises a tank 9 having a crude oil inlet 6, a water outlet 7 and a crude oil outlet 8, wherein a plurality of, for example, two electrode plates 10 are arranged in the tank 9 at intervals in the height direction, for example, the electrode plates 10 are hung on the tank 9 by insulating hangers 12, while the electrode plates in the lower layer can be hung on the electrode plates in the upper layer or can be directly hung on the tank 9, and the electrode plates 10 are wave-shaped electrode plates.

Because the electrode plates are wave-shaped electrode plates, the lower electrode plate is connected with an alternating current power supply such as a transformer 13, the upper electrode plate is grounded, and the oil-water layer interface at the bottom in the electric desalting tank is also used as a grounded electrode plate, a strong electric field is formed between the two electrode plates, and a weak electric field is formed between the lower electrode plate and the oil-water layer interface. Therefore, the oil-water mixture enters the electric desalting tank from the bottom of the electric desalting tank, rapidly rises through an oil-water layer interface, enters a weak electric field area, and then enters a strong electric field area through a lower electrode plate. Under the action of an electric field, salt-containing small droplets in the oil-water mixture are aggregated into large droplets, the large droplets are settled out from the crude oil and enter a continuous water phase at the bottom of the electric desalting tank, salt-containing sewage can be discharged through a water outlet at the bottom of the tank, and the dehydrated crude oil flows out from an upper collector of the electric desalting tank. When the oil-water mixture passes through the electrode plates from bottom to top, the effective contact area between the liquid drops and the electrode plates is increased because the plurality of electrode plates are arranged at intervals along the wave-shaped curve, the flowing direction of the oil-water mixture is consistent with the direction of an electric field in a strong electric field area, the electrostatic acting force between the liquid drops is increased, the electrode plates are bare electrodes, the liquid drops are charged after contacting the electrode plates, the dipole coalescence and electrophoretic coalescence processes between the liquid drops are enhanced, the wave-shaped inclined planes of the wave-shaped electrode plates are beneficial to rolling of large liquid drops, the oil-water separation effect is enhanced, the large liquid drops can form water films at the intervals penetrating through the thickness of the electrode plates, the water films can enhance the liquid drop-interface coalescence effect in the electrocoagulation process, and in addition, under the condition of high and low fluctuation of the oil-water layer interface, the wave-shaped electrode, this is advantageous for improving the desalting and dewatering effect of the crude oil.

Further, the height of the electrode plates 10 and the interval between the adjacent electrode plates 10 can be adjusted. For example, the hanger comprises a multi-section rod with the length capable of being adjusted in a telescopic mode, the multi-section rod is adjusted to a required height position and then fixed in position, and the rod body can be locked through a radial locking screw to fix the position. The hanging height of each electrode plate can be adjusted respectively. Thus, the height position of the electrode plate 10 can be adjusted accordingly according to the actual demand for electric desalting and dewatering.

It should be noted that, in the electric desalting tank of the present invention, the wavy electrode plate may be a wavy plate, and the wavy plate may have a plurality of through holes penetrating through the thickness of the plate, and the through holes may be circular holes, strip-shaped holes or holes of any other shape, so as to facilitate the passage of oil-water mixture and crude oil.

Alternatively, the corrugated electrode plate may be any of the electrode plates described above in relation to the first aspect, for example, an electrode plate formed of two corrugated beams and a plurality of electrode rods.

Of course, the electric desalting tank of the invention further comprises a distributor 11 and an upper collector 14, so that the oil-water mixture can enter the tank from the distributor 11, the dehydrated and desalted crude oil floats to the top and is collected by the upper collector 14 and then is discharged from a crude oil outlet 8, and the water settled to the bottom of the tank can be discharged from a water discharge port 7 at the bottom of the tank.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, numerous simple modifications can be made to the technical solution of the invention, including that the individual specific technical features can be combined in any suitable way. The invention is not described in detail in order to avoid unnecessary repetition. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.

Claims

1. An electrode plate, characterized by comprising a plurality of electrode rods (1) and a plurality of support beam bodies (2), wherein a plurality of the support beam bodies (2) are arranged at intervals to form electrode rod setting intervals (3) between the adjacent support beam bodies (2), wherein a plurality of the electrode rods (1) are arranged at intervals in the electrode rod setting intervals (3) in the extending direction of the support beam bodies (2), and a plurality of the electrode rods (1) are arranged at intervals along a wave-shaped curve.

2. The electrode plate according to claim 1, characterized in that a plurality of the electrode rods (1) are arranged in parallel with each other, and both ends of each of the electrode rods (1) are respectively connected to the support beam bodies (2) corresponding to the respective ends.

3. Electrode plate according to claim 1, characterized in that the support beam body (2) is wave-shaped.

4. Electrode plate according to claim 3, characterized in that the undulating course of a plurality of support beam bodies (2) is identical.

5. The electrode plate according to claim 4, characterized in that the upper wavy surface (4) of the support beam body (2) is formed by the equation y-sin (x) and the lower wavy surface (5) of the support beam body (2) is formed by the equation y-sin (x) -0.2, wherein 0< x <2 pi.

6. The electrode plate according to claim 1, wherein the plurality of electrode rods (1) are arranged at equal intervals along a curve y ═ sin (x) -0.1, wherein 0< x <2 pi.

7. The electrode plate according to any one of claims 1 to 6, characterized in that a plurality of the support beam bodies (2) are electrically conductive beam bodies.

8. The electric desalting tank is characterized by comprising a tank body (9) with a crude oil inlet (6), a water outlet (7) and a crude oil outlet (8), wherein a plurality of electrode plates (10) are arranged in the tank body (9) at intervals in the height direction, and the electrode plates (10) are wavy electrode plates.

9. The electrodeionization tank of claim 8, wherein the height of said electrode plates (10) and the spacing between adjacent electrode plates (10) are adjustable.

10. The electrodeionization tank of claim 8 or 9, wherein the electrode plate (10) is according to any one of claims 1 to 7.