CN106964502B - A kind of three-phase cyclone separator with helical structure - Google Patents

Abstract

A three-phase cyclone separator with a spiral structure. The main purpose is to provide a three-phase cyclone separation device with compact structure, small equipment volume and good separation effect. It is characterized in that: the inner cylinder with a frustum-like structure inside is placed inside the outer cylinder and kept coaxial with the outer cylinder; the inner diameter of the swirl section of the inner cylinder is larger than the inner diameter of the water phase outlet section, and along the swirl section The outer wall of the bottom end is tangentially connected to two internal tangential inlets; on the inner wall of the outer cylinder, several outer helical structures arranged along the circumference are fixed, and the outer helical structures are distributed from the lower end of the tangential inlet; On the inner wall surface of the small cone section of the inner cylinder, there are inner helical structures distributed; the helical direction of the outer helical structure is the same as that of the liquid flow in the outer cylinder formed by the tangential inlet, and the inner helical structure The direction of rotation is opposite to that of the outer helical structure.

Description

A three-phase cyclone separator with spiral structure

technical field

The invention relates to a device for separating multiphase media used in the fields of petroleum, chemical industry, marine engineering, water treatment and environmental protection.

Background technique

At present, cyclones are more and more widely used in petroleum, chemical and coal industries. The use of gravity settling tanks and three-phase separation cyclones is currently the main equipment for people to separate three-phase mixed liquids. Among them, the gravity settling tank is relatively large in volume, and is usually equipped with weir plates and other components inside, and its structure is relatively complicated. In addition, since gravity is used for separation treatment, it leads to long treatment time, discontinuous work, and large floor space. However, for the existing three-phase separation cyclone, when it separates the mixed phase, there are problems such as unstable flow field and too low velocity of the liquid flow to a position far from the inlet. Therefore, how to design a separation cyclone with high separation efficiency, small space occupation, stable flow field, wide application and convenient operation and maintenance has become an important problem faced by petrochemical and other related fields.

As a kind of separation equipment, cyclone has been applied to a certain extent in our country, and the invention patent of three-phase separation cyclone has also attracted more and more attention. Northeast Petroleum University (formerly Daqing Petroleum Institute) has applied for a number of invention patents, such as ZL201510366926.7, ZL201410675327.9, ZL201410658938.2, ZL201210345243.X, ZL201210346843.8, ZL201210196492.7, etc.; Patents such as ZL201520519735.5, ZL201520520103.0, ZL201420185334.6, ZL201310582217.3, ZL201210292638.8, etc. The above patents are mainly to increase related devices for auxiliary separation to carry out separation, the most representative one is to add spiral guide vanes in the swirler. However, the above improvements are still difficult to meet the requirements of high separation efficiency, small space occupation and stable flow field under some special working conditions.

Contents of the invention

In order to solve the technical problems mentioned in the background technology, the present invention provides a three-phase cyclone separator with a spiral structure, which has many outstanding features such as high separation efficiency, compact structure and easy processing. .

The technical solution of the present invention is: the three-phase cyclone separator with a spiral structure includes an outer cylinder, and the upper and lower ends of the outer cylinder are respectively coaxially connected with an upper end cover and a lower end cover. The outer wall at the top of the outer cylinder is tangentially connected to two tangential inlets, which are unique in that:

The center of the upper end cover is vertically connected with an air guide outer cylinder, the lower end of the air guide outer cylinder is a bell-shaped gradual expansion section, and the air guide outer cylinder and the upper end cover have the same central axis;

An oil phase outlet pipe is vertically connected to the center of the lower end cover. Around the oil phase outlet pipe, a frustum-like structure with a concave arc surface is fixed. The bottom end of the frustum-like structure is connected to the lower end cover. Touch, the top of the frustum-like structure is flush with the outlet of the oil phase outlet pipe; the frustum-like structure has the same central axis as the oil phase outlet pipe and the lower end cover;

The three-phase cyclone separator also includes an inner cylinder, and the inner cylinder is composed of a water phase outlet section, a small cone section, a large cone section and a swirl section connected in sequence from top to bottom with the same central axis. The outlet section of the water phase and the swirl section are straight pipe sections, and the inner diameter of the swirl section is greater than the inner diameter of the outlet section of the water phase; two internal tangential inlets are connected tangentially along the outer wall of the bottom end of the swirl section;

The inner cylinder is located in the outer cylinder; among them, the water phase outlet section passes through the air guide outer cylinder, and the annular gap formed between the two is the annular air phase outlet; the bottom end of the swirl section is connected to the lower end cover, which is similar to the truncated cone structure The body is located in the inner cavity of the swirl section, and the frustum-like structure has the same central axis as the inner cylinder;

On the inner wall of the outer cylinder, several outer helical structures arranged along the circumference are fixed, and the outer helical structures are distributed from the lower end of the tangential inlet; on the inner wall of the small cone section of the inner cylinder, there are distributed Inner helical structure; the helical direction of the outer helical structure is the same as that of the liquid flow in the outer cylinder formed through the tangential inlet, and the helical direction of the inner helical structure is opposite to that of the outer helical structure.

The present invention has the following beneficial effects: In this three-phase separation cyclone with spiral structure, the inner cylinder is turned upside down and placed inside an outer cylinder, and the outer wall of the inner cylinder is provided with an internal tangential inlet, which is set at the bottom of the swirl section On the one hand, it eliminates the low-pressure area in the cyclone chamber, reduces the pressure difference between the inlet and the overflow port, and reduces the short-circuit flow generated by entering the cyclone directly from the overflow port without separation. , improving the separation efficiency. In addition, the double helical channel structure of the inner and outer cylinders of the hydrocyclone can stabilize the flow field and have a certain swirling effect on the mixed phase, which can increase the fluid rotation speed and guide the fluid flow, thereby improving the separation efficiency. In addition, this kind of separator can not only realize oil-gas-water, gas-liquid-solid three-phase separation, but also realize two-phase fine separation of two phases (liquid-solid, gas-liquid and liquid-liquid) by changing the size parameters of related structures. Treatment, taking gas-liquid separation as an example, after the initial gas-liquid separation in the external separation section, the residual gas in the liquid is separated through the inner cylinder, so as to improve the separation efficiency.

To sum up, this kind of three-phase separation cyclone with spiral structure has the advantages of high separation efficiency, stable flow field, compact structure, easy processing, wide application, small equipment size and convenient operation and maintenance, etc., which can effectively solve the problem of Related fields face problems such as high cost of three-phase separation equipment, large area occupation, and discontinuous treatment process in actual production.

Description of drawings:

Fig. 1 is a top view structural diagram of the present invention.

FIG. 2 is a schematic diagram of the A-A section structure in FIG. 1 .

FIG. 3 is a schematic cross-sectional structure diagram of the B-B section in FIG. 2 .

Fig. 4 is a main dimensional drawing of the present invention.

Fig. 5 is a side view of the three-phase separation cyclone according to the present invention after part of the outer cylinder and the inner cylinder are removed.

In the figure, 1-tangential inlet, 2-annular air phase outlet, 3-external helical structure, 4-internal tangential inlet, 5-lower end cover, 6-type frustum structure, 7-oil phase outlet pipe, 8 - swirl section, 9-large cone section, 10-inner cylinder, 11-outer cylinder, 12-small cone section, 13-inner spiral structure, 14-water phase outlet section, 15-upper end cover, 16-guide Air cylinder.

Detailed ways:

The present invention will be further described below in conjunction with accompanying drawing:

As shown in Figure 1, this kind of three-phase cyclone separator with a spiral structure includes an outer cylinder 11, and the upper and lower ends of the outer cylinder 11 are respectively coaxially connected with an upper end cover 15 and a lower end cover 5, Two tangential inlets 1 are connected tangentially along the outer wall of the top of the outer cylinder, and its unique features are:

The center of the upper end cover 15 is vertically connected with an air guide outer cylinder 16 , the lower end of the air guide outer cylinder 16 is a flared section in the shape of a bell mouth, and the air guide outer cylinder 16 and the upper end cover 15 have the same central axis.

The center of the lower end cover 5 is vertically connected with an oil phase outlet pipe 7, surrounding the oil phase outlet pipe 7, a frustum-like structure 6 with an inner concave arc surface is fixed, the bottom of the frustum-like structure 6 The top of the frustum-like structure 6 is flush with the outlet of the oil phase outlet pipe 7; the frustum-like structure 6 has the same central axis as the oil phase outlet pipe 7 and the lower end cover 5.

The three-phase cyclone separator also includes an inner cylinder 10, and the inner cylinder 10 is composed of a water phase outlet section 14 having the same central axis, a small cone section 12, a large cone section 9 and a swirl section from top to bottom. 8 are connected in sequence; the water phase outlet section 14 and the swirl section 8 are straight pipe sections, and the inner diameter of the swirl section 8 is greater than the inner diameter of the water phase outlet section 14; Internal tangential entrance 4.

The inner cylinder 10 is located in the outer cylinder 11; wherein, the water phase outlet section 14 passes through the air guide outer cylinder 16, and the annular gap formed between the two is the annular air phase outlet 2; the bottom end of the swirl section 8 is connected to the lower end On the cover 5 , the frustum-like structure 6 is located in the inner cavity of the swirl section 8 , and the truncated-cone structure 6 and the inner cylinder 10 have the same central axis.

On the inner wall of the outer cylinder 11, several outer helical structures 3 arranged along the circumference are fixed, and the outer helical structures 3 are distributed from the lower end of the tangential inlet 1; On the inner wall surface, internal helical structures 13 are distributed; the direction of rotation of the external helical structures 3 is the same as that of the liquid flow in the outer cylinder 11 formed through the tangential inlet 1, and the direction of rotation of the internal helical structures 13 The direction of rotation is opposite to that of the outer helical structure 3.

In practice, the edge cross-section of the helical structure can be trapezoidal, elliptical or circular, etc., wherein the outer helical structure starts from the lower end of the entrance, and the helical structure is left-handed, while the inner helical structure is right-handed.

Taking the oil-gas-water three-phase mixed medium as an example, the mixed fluid enters the cyclone from double tangential inlets, changing the linear motion of the mixed medium into a circular motion, and the fluid moves downward while rotating. Due to the existence of the inner cylinder, the external gas The cross-sectional area of the liquid separation space gradually decreases. At the same time, the fluid flows along the outer helical structure on the inner wall of the outer cylinder. The helical channel formed by the outer helical structure has a certain flow guiding and swirling effect on the fluid, and the liquid phase with higher density is thrown towards the The side wall, while the gas phase with low density migrates to the outer wall of the inner cylinder structure, and finally is discharged from the annular air phase outlet at the top. Most of the liquid and a very small part of the gas that has not been separated enter the inner cylinder through the internal tangential inlet, and the mixed medium rotates in the inner cavity of the swirl section with a frustum-like structure (the generatrix is an arc) , the design of the frustum-like structure eliminates the low-pressure area at the top of the cyclone chamber, which not only reduces the pressure difference between the inlet and the oil phase outlet, but also reduces the direct discharge from the oil phase outlet of the cyclone without separation. The generated short-circuit flow improves the separation efficiency. The mixed medium that flows continuously in the back pushes the mixed medium in the swirl chamber to move toward the large cone section and small cone section on the inner cylinder while rotating. The fluid has a certain guiding effect, which makes the flow field more stable and facilitates the separation of oil and water. The oil droplets with lower density gather toward the middle while rotating and are finally discharged from the oil phase outlet at the bottom, while the water phase with higher density is thrown to the side wall and then discharged from the water phase outlet. Finally, the three-phase separation of oil, gas and water is realized.

A preferred embodiment of the present invention, in this example, is given below in conjunction with FIG. 4 for specific implementation. The main parameters and dimensions of this kind of separator are necessary to be limited:

As shown in the figure, a ₁ and b ₁ are the equivalent height and width of the inlet of the outer cylinder of the cyclone respectively; v ₁ is the inlet velocity of the outer cylinder of the cyclone; a ₂ and b ₂ are the equivalent of the inlet of the inner cylinder of the cyclone respectively height and width; v ₂ is the inlet velocity of the inner cylinder of the cyclone; l ₁ is the radial height of the edge of the outer helical structure, l ₂ is the radial height of the edge of the inner helical structure, l ₃ is the small cone section of the cyclone height; P ₁ is the lead of the outer helical structure, P ₂ is the lead of the inner helical structure; Q is the processing capacity of the separator; D ₁ is the main diameter of the outer cylinder of the cyclone, and D ₂ is the swirling flow The main diameter of the inner cylinder of the device, _D3 is the diameter of the outlet section of the water phase of the cyclone; t is the wall thickness of the cyclone;

Then the three-phase cyclone separator needs to meet the following conditions (1) to (8):

Condition (1): b ₁ =Q/(2v ₁ ×a ₁ ), and the range of v ₁ is between 8 m/s ~15m/s;

Condition (2): b ₂ =Q/(2v ₂ ×a ₂ ), and the range of v ₂ is between 4 m/s ~10m/s;

Condition (3): ;

Condition (4): ;

Condition (5): D ₃ =0.5D ₂ ;

Condition (6): 0.5D ₁ <D ₂ <0.75D ₁ ;

Condition (7): 0<P ₁ <l ₀ -a ₁ -a ₂ ;

Condition (8): 0<P ₂ <l ₃ .

The reason for the above limitation is that the swirler has two cylinders, and the edge of the helical structure is between the two cylinders. If the radial dimension of the edge is too long, it will not only affect the flow field, but also cause the edge and Structural interference occurs in the inner cylinder of the cyclone, which makes the cyclone unable to use normally; if the radial dimension of the rib is too short, it will not be able to create swirl and stabilize the flow field. Therefore, it is necessary to limit the radial size of the ribs of the helical structure.

P determines the angle of rise, height, and number of turns of the helical structure of the cyclone. If P is not restricted, the helical structure of the cyclone may cause the inlet of the cyclone to be blocked, affecting the normal use of the cyclone and affecting the normal use of the cyclone. The flow field also has a great influence, so that the swirler with this structure cannot function effectively.

Claims (2)

1. a kind of three-phase cyclone separator with helical structure, including an outer cylinder (11), the upper/lower terminal of outer cylinder (11) Coaxial line is connected with upper end cover (15) and bottom end cover (5) respectively, and the outer wall along the outer cylinder (11) top tangentially accesses two Tangential inlet (1), it is characterised in that：

The center of the upper end cover (15) is vertically connected with an air guide outer barrel (16), and the lower end of air guide outer barrel (16) is in loudspeaker The divergent segment of mouth shape, air guide outer barrel (16) and upper end cover (15) central axis having the same；

The center of the bottom end cover (5) is vertically connected with an oil phase outlet pipe (7), fixed around the oil phase outlet pipe (7) There are one the class frustum structure body (6) using inner concave arc surface, bottom end and the bottom end cover (5) of class frustum structure body (6) touch, class cone The outlet flush on the top and oil phase outlet pipe (7) of platform structure (6)；Class frustum structure body (6) and oil phase outlet pipe (7) with And bottom end cover (5) central axis having the same；

The three-phase cyclone separator further includes an inner cylinder (10), and the inner cylinder (10) is from top to bottom respectively by in same Water phase outlet section (14), small cone section (12), large cone section (9) and the eddy flow section (8) of mandrel line are constituted after being sequentially connected with；Water phase goes out Mouth section (14) and eddy flow section (8) are straight pipe, and the internal diameter of eddy flow section (8) is more than the internal diameter of water phase outlet section (14)；Along eddy flow section (8) outer wall of bottom end tangentially accesses two internal tangential inlets (4)；

Inner cylinder (10) is located in outer cylinder (11)；Wherein, water phase outlet section (14) is pierced by air guide outer barrel (16), is formed between the two Annular gap be annular space gaseous phase outlet (2)；The bottom end of eddy flow section (8) is connected on bottom end cover (5), class frustum structure body (6) In the inner cavity of eddy flow section (8), class frustum structure body (6) and inner cylinder (10) central axis having the same；

Inner wall in outer cylinder (11) is fixed with several external spiral structures (3) circumferentially arranged, the external spiral structure Body (3) is distributed since the lower end of tangential inlet (1)；At the internal face of the small cone section (12) of the inner cylinder (10), it is distributed with Inside spin structure (13)；The rotation direction of the external spiral structure (3) with via tangential inlet (1) be formed by outer cylinder (11) Interior liquid stream direction of rotation is identical, and the rotation direction of inside spin structure (13) is oppositely oriented with external spiral structure (3).

2. a kind of three-phase cyclone separator with helical structure according to claim 1, it is characterised in that：

l₀It is the height of cyclone outer cylinder, a₁And b₁It is cyclone outer cylinder entrance equivalent altitude and width respectively；v₁It is eddy flow Device outer cylinder entrance velocity；a₂And b₂It is cyclone inner cylinder entrance equivalent altitude and width respectively；v₂It is cyclone inner cylinder entrance speed Degree；l₁For the radial height of external spiral structure rib, l₂It is the radial height of inside spin structure rib, l₃It is cyclone small cone section Height；P₁For the helical pitch of external spiral structure, P₂For the helical pitch of inside spin structure；Q is the treating capacity of separator；D₁It is rotation Flow device outer cylinder full diameter, D₂It is cyclone inner cylinder full diameter, D₃It is cyclone water phase exducer diameter；T is the wall of cyclone It is thick；

Then the three-phase cyclone separator needs to meet following condition (1) to condition (8)：

Condition (1)：b₁=Q/ (2v₁×a₁), and v₁Range between 8m/s~15m/s；

Condition (2)：b₂=Q/ (2v₂×a₂), and v₂Range between 4m/s~10m/s；

Condition (3)：

Condition (4)：

Condition (5)：D₃=0.5D₂；

Condition (6)：0.5D₁<D₂<0.75D₁；

Condition (7)：0<P₁<l₀-a₁-a₂；

Condition (8)：0<P₂<l₃。