Gas-liquid-solid separation device

Abstract

The invention discloses a gas-liquid-solid separation device which comprises a tank body, and a gas-liquid guide device, a demister and a spraying device which are sequentially mounted in the tank body from bottom to top, the gas-liquid flow guide device comprises a variable-diameter barrel with an upper opening and a lower opening, so that the speed-reduced flow of gas-liquid phase fluid is realized; the lower surface of the demister and the upper surface of the gas-liquid guide device are arranged at an interval, and a turbulent flow area is formed between the demister and the gas-liquid guide device; and the spraying device is used for spraying mineral oil towards the area where the demister is located. According to the reciprocating compressor, the turbulence capacity of gas-phase fluid can be improved, contact coalescence of liquid drops is promoted, the liquid content of a gas-phase outlet is reduced, and the operation stability of the reciprocating compressor is improved.

Description

Technical Field

[0001] The invention relates to a gas-liquid-solid separation device, and in particular to a gas-liquid-solid separation device suitable for a polyolefin industry chain. Background Art

[0002] In the propylene bulk polymerization process, the recovery of propylene after polymerization is one of the key units of the process. It mainly uses a circulating gas reciprocating compressor to pressurize low-pressure propylene and then cool it down to obtain liquid propylene. After long-term use, the circulating gas reciprocating compressor will have liquid phase and fine powder residues, which will affect the operating stability of the reciprocating compressor.

[0003] At present, the industry widely uses a separation tank with a demister for gas-liquid-solid separation. The following technical problems exist during use: 1. After the gas enters the gas-liquid separation tank from the inlet, a vortex will be formed at the nozzle, which will indirectly enhance the effect of mist entrainment and affect the sedimentation of fine powder and fine droplets; 2. After the gas enters the gas-liquid separation tank, the flow pattern is relatively fixed, and the gas flow direction will basically not change, which reduces the aggregation and sedimentation of droplets, and small-size droplets are directly taken out of the gas-liquid separation tank by the gas; 3. After the droplets and fine powder are brought into the demister by the gas, the larger droplets are intercepted by the wire mesh, which increases the pressure drop and flow rate of the gas at the wire mesh, and the droplets cannot flow out of the wire mesh, and more smaller droplets are taken out of the wire mesh demister. In order to avoid the above problems and achieve long-term stable operation of the device, effective measures need to be taken to make more droplets and fine powder settle in the gas-liquid separation tank to avoid the problem of increased pressure drop and too many droplets being taken out of the gas-liquid separation tank. How to enhance the turbulence of the fluid in the gas-liquid separation tank to promote the aggregation of droplets and fine powder is a key issue.

[0004] Therefore, it is very important to develop a separation tank suitable for gas-liquid phase separation containing solid powder, which is used to reduce the amount of fine powder and small droplets carried out of the gas-liquid separation tank, ensure the continuous and stable operation of the compressor, and improve the stable operation of the gas-liquid separation tank. Summary of the invention

[0005] To this end, the present invention proposes a separation device for gas-liquid-solid separation, which can increase the turbulence capacity of the gas phase fluid, promote the contact and aggregation of droplets, help reduce the liquid content at the gas phase outlet, and improve the operating stability of the reciprocating compressor.

[0006] In view of the above technical problems, the present invention provides the following technical solutions:

[0007] A gas-liquid-solid separation device comprises: a tank body, a gas-liquid flow guiding device, a demister and a spraying device which are sequentially installed in the tank body from bottom to top; the gas-liquid flow guiding device comprises a variable diameter cylinder with upper and lower openings to realize the flow reduction of gas-liquid phase fluid; the lower surface of the demister is spaced from the upper surface of the gas-liquid flow guiding device to form a turbulent flow zone therebetween; the spraying device is used to spray mineral oil toward the area where the demister is located.

[0008] In some embodiments of the present invention, the variable diameter cylinder of the gas-liquid diversion device is constructed as a cylinder structure that expands from bottom to top, the lower end of the variable diameter cylinder forms a gas-liquid inlet, and the upper end of the variable diameter cylinder is fixedly connected to the tank body through an annular plate extending in the horizontal direction, and a plurality of jet holes are arranged on the annular plate.

[0009] In some embodiments of the present invention, a plurality of rows of jet holes evenly arranged circumferentially are radially arranged on the annular plate, a guide plate is provided on the upper surface of the annular plate in the hole wall area of ​​the jet holes, and the guide plate extends obliquely toward the center line of the tank body.

[0010] In some embodiments of the present invention, the jet holes extend obliquely toward the center line of the tank body, the angle between the jet hole extension direction and the vertical direction is 10°-20°, and the area of ​​all the jet holes on the annular plate accounts for 25%-40% of the area of ​​the annular plate.

[0011] In some embodiments of the present invention, a feed inlet is provided on the side wall of the tank body, and the feed inlet and the gas-liquid inlet of the gas-liquid guiding device are on the same horizontal plane.

[0012] In some embodiments of the present invention, the variable diameter cylinder of the gas-liquid flow guiding device includes a cylindrical cylinder located at the lower side and a frustoconical cylinder located at the upper side of the cylindrical cylinder.

[0013] In some embodiments of the present invention, the lower side of the cylindrical body has a guide wall that is inclined inward and has an arc-shaped transition, and the angle between the extension direction of the guide wall and the generatrix of the cylindrical body is 10°-20°.

[0014] In some embodiments of the present invention, the inner diameter of the cylindrical body accounts for 45%-55% of the inner diameter of the tank body, and the maximum inner diameter of the frustum body accounts for 75%-85% of the inner diameter of the tank body.

[0015] In some embodiments of the present invention, the spraying device includes a spraying body and fan blades rotatably connected to the spraying body, and the fan blades rotate around the spraying body under the action of the driving device.

[0016] In some embodiments of the present invention, an exhaust port is provided on the top of the tank body, and the exhaust port is connected to the compressor air intake pipeline. The compressor air intake pipeline is provided with a detection device for detecting the powder content in the gas, and the control device controls the spraying device to spray mineral oil according to the set cycle based on the signal of the detection device.

[0017] The technical solution of the present invention has the following technical effects compared with the prior art:

[0018] In the gas-liquid-solid separation device provided by the present invention, the gas-liquid flow guide device includes a variable diameter cylinder with upper and lower openings. After the gas passes through the variable diameter cylinder, the flow rate changes from high to low and then enters the turbulent area and the mist-foam separation area more smoothly. The spraying device is used to spray mineral oil toward the area where the demister is located. Spraying mineral oil through the demister and the spraying device can intercept more fine powder and droplets, thereby achieving a better gas-liquid separation effect. At the same time, the gas phase fluid carries the mineral oil into the compressor, which can also lubricate the compressor. The gas-liquid-solid separation device is used to remove liquid and solid phases before the reciprocating compressor, strengthen the aggregation and sedimentation of droplets and fine powders by changing the flow rate of the gas phase fluid, and guide them into the liquid phase space through the gas-liquid flow guide device, thereby improving the droplet removal effect, thereby improving the operating stability of the reciprocating compressor, and facilitating the long-term operation of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, which will help to understand the objects and advantages of the present invention, wherein:

[0020] Figure 1 It is a structural schematic diagram of a specific embodiment of the gas-liquid-solid separation device of the present invention;

[0021] Figure 2 It is a schematic diagram of a specific implementation of the gas-liquid flow guiding device in the gas-liquid-solid separation device of the present invention;

[0022] Figure 3 A top view of a specific embodiment of the annular plate in the gas-liquid-solid separation device of the present invention;

[0023] Figure 4 A cross-sectional view of a specific embodiment of the annular plate in the gas-liquid-solid separation device of the present invention;

[0024] Figure 5 It is a schematic diagram of a specific implementation of the spraying device in the gas-liquid-solid separation device of the present invention. DETAILED DESCRIPTION

[0025] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0027] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0029] like Figure 1 The figure shows a specific embodiment of the gas-liquid-solid separation device of the present invention, which is used to be installed on the air intake pipeline of the circulating gas reciprocating compressor to remove liquid and solid impurities. It includes a tank body 100, a gas-liquid flow guiding device 10, a demister 20 and a spraying device 30 which are sequentially installed in the tank body 100 from bottom to top; the gas-liquid flow guiding device 10, the demister 20 and the spraying device 30 are arranged at intervals from each other, and the tank body 100 is divided into a liquid phase area 100a, a speed change area 100b, a turbulent flow area 100c and a mist and foam separation area 100d which are sequentially arranged from top to bottom; specifically, the lower side of the gas-liquid flow guiding device 10 is the liquid phase area 100a, the area where the gas-liquid flow guiding device 10 is located is the speed change area 100b, the area between the demister 20 and the gas-liquid flow guiding device 10 is the turbulent flow area 100c, and the part above the demister 20 is the mist and foam separation area 100d.

[0030] Specifically, the gas-liquid flow guiding device 10 includes a variable diameter cylinder 11 with upper and lower openings. After the gas passes through the variable diameter cylinder 11, the flow rate changes from high to low and then enters the turbulent flow area 100c and the mist and foam separation area 100d more smoothly. The spraying device 30 is used to spray mineral oil toward the area where the demister 20 is located. Spraying mineral oil through the demister 20 and the spraying device 30 can intercept more fine powder and droplets, thereby achieving a better gas-liquid separation effect. At the same time, the gas phase fluid carries mineral oil into the compressor, which can also lubricate the compressor. The gas-liquid-solid separation device is used to remove liquid and solid phases before the reciprocating compressor, strengthen the aggregation and sedimentation of droplets and fine powders by changing the flow rate of the gas phase fluid, and guide the gas-liquid flow guiding device 10 into the liquid phase space, thereby improving the droplet removal effect, thereby improving the operating stability of the reciprocating compressor, and facilitating the long-term operation of the device.

[0031] Specifically, in an optional embodiment, the speed change zone 100b occupies half of the volume of the tank body 100, the variable diameter cylinder 11 of the gas-liquid flow guiding device 10 is constructed as a cylinder structure that expands from bottom to top, the lower end of the variable diameter cylinder 11 forms a gas-liquid inlet, and the upper end of the variable diameter cylinder 11 is fixedly connected to the tank body 100 through an annular plate 12 extending in the horizontal direction, and a plurality of jet holes 121 are arranged on the annular plate 12. The gas-liquid flow guiding device 10 separates the gas-liquid phase fluid in the tank body 100 into two parts, the inner and outer parts, the flow rate of the internal fluid changes from high to low after passing through the variable diameter cylinder 11, and the external fluid changes from low to high and enters the turbulent flow zone 100c through the jet holes 121, and the high and low speed fluids are further mixed in the turbulent flow zone 100c and enter the mist separation zone 100d, which can make the liquid and fine powder in the gas-liquid phase fluid gather into larger droplets, and can achieve better separation of gas and liquid phases. The jet hole 121 optimizes the distribution of the gas phase in the annular area and the cylindrical area by increasing the pressure drop in the annular area, which can effectively improve the problem of uneven gas distribution and increase the degree of gas turbulence, thereby improving the mass transfer and separation efficiency. Experiments have found that the jet hole can increase the fluid pressure drop in the annular area by about 1 kPa.

[0032] Specifically, the annular plate 12 is provided with a plurality of rows of jet holes 121 evenly arranged in the circumferential direction in the radial direction, and the upper surface of the annular plate 12 is provided with a guide plate 13 in the hole wall area of ​​the jet hole 121, and the guide plate 13 extends obliquely toward the center line direction of the tank body 100, so that the fluid flowing upward through the jet hole 121 flows toward the center line direction of the tank body 100, and quickly mixes with the fluid passing through the inside of the variable diameter cylinder 11, thereby optimizing the mixing efficiency of the turbulent zone 100c. More specifically, the angle between the extension direction of the guide plate 13 and the vertical direction is between 15° and 30°, which can reduce the fluid velocity to a small extent and ensure the mixing efficiency of the turbulent zone 100c.

[0033] Specifically, in an optional embodiment, the jet hole 121 extends obliquely toward the center line of the tank body 100, and the angle between the extension direction of the jet hole 121 and the vertical direction is 10°-20°. The area of ​​all the jet holes 121 on the annular plate 12 accounts for 25%-40% of the area of ​​the annular plate 12, which can make the flow rate of the gas phase fluid passing through the jet hole reach 40-50m / s, which is beneficial to the gas mixing in the turbulent zone 100c.

[0034] Specifically, in an optional embodiment, the side wall of the tank body 100 is provided with a feed port 101, and the feed port 101 is on the same horizontal plane as the gas-liquid inlet of the gas-liquid flow guiding device 10. After the gas-liquid phase fluid enters the tank body 100, it is directly divided into two flow channels under the action of the gas-liquid flow guiding device 10, thereby improving the gas-liquid separation efficiency of the fluid. More specifically, the tank body 100 is provided with a plurality of evenly distributed feed ports 101 along the circumference, so that the gas-phase fluid can be evenly distributed in the outer flow channel, which is conducive to full utilization of the outer flow channel space.

[0035] Specifically, in an optional embodiment, the variable diameter cylinder 11 of the gas-liquid flow guiding device 10 includes a cylindrical cylinder 111 located at the lower side and a truncated cone cylinder 112 located at the upper side of the cylindrical cylinder 111. The inner diameter of the cylindrical cylinder 111 accounts for 45%-55% of the inner diameter of the tank body 100, and the maximum inner diameter of the truncated cone cylinder 112 accounts for 75%-85% of the inner diameter of the tank body 100. The height ratio of the cylindrical cylinder 111 to the height of the truncated cone cylinder 112 is 1:3-1:2. By adopting the variable diameter cylinder 11 in the above size range, the flow rate of the fluid inside the variable diameter cylinder 11 can be reduced by about 50% from the gas-liquid inlet to the gas-liquid outlet, and the flow rate of the fluid outside the variable diameter cylinder 11 is increased by 1-2 times from the lower side to the position of the annular plate 12, which is further conducive to the rapid mixing of the gas-liquid phase fluid in the turbulent area 100c.

[0036] Specifically, in an optional embodiment, the lower side of the cylindrical body 111 has a guide wall 113 that is inclined inward and has an arc transition, and the angle between the extension direction of the guide wall 113 and the generatrix of the cylindrical body 111 is 10°-20°. By providing the guide wall 113 at the gas-liquid inlet section, the droplets on the inner wall of the variable diameter cylinder 11 can be gathered, and the gathered droplets can flow downward in bundles.

[0037] Specifically, in an optional embodiment, the mist separation zone 100d occupies 15%-20% of the height of the tank body 100, and the demister 20 part occupies approximately 8%-12% of the height of the tank body 100. The demister 20 uses wire mesh structured packing, and the wire mesh model can be selected according to different polymer product models.

[0038] The spraying device 30 includes a spraying body 31 and fan blades 32 rotatably connected to the spraying body 31. The fan blades 32 can periodically rotate around the spraying body 31 under the action of a driving device. The nozzle of the spraying body 31 can spray mineral oil to improve the mass transfer and separation effect. The fan blades 32 can increase the flow rate of the mineral oil in the demister 20 to prevent the mineral oil from being deposited on the wire mesh of the demister 20.

[0039] The nozzle of the spray body 31 sprays mineral oil in a fan shape to the entire demister 20, and the purpose of removing droplets and fine powder in the gas phase is achieved through the contact and mass transfer exchange between the mineral oil and the fluid. The added fan blades 32 can change the residence time of the mineral oil in the wire mesh filler by adjusting different rotation speeds, thereby improving the gas-liquid contact efficiency. By utilizing the contact between the mineral oil and the liquid-containing gas flow, when the droplet size is 3 to 5 microns, the liquid content of the outlet gas phase can be reduced to 100ppm.

[0040] An exhaust port 102 is provided on the top of the tank body 100, and the exhaust port 102 is connected to the compressor intake pipeline A. The compressor intake pipeline A is provided with a detection device B for detecting the powder content in the gas. The control device C controls the spraying device 30 to spray mineral oil according to a set period according to the signal of the detection device B, so that the spraying device 30 can regularly spray minerals and backwash regularly under conditions with high powder content, thereby reducing the powder content in the gas for lubrication of the compressor cylinder.

[0041] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. However, the obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A gas-liquid-solid separation device, characterized in that: include: The tank body, the gas-liquid guide device, the demister and the spray device installed in the tank body from bottom to top; The gas-liquid flow guiding device comprises a variable diameter cylinder with upper and lower openings to achieve the flow reduction of gas-liquid phase fluid; The lower surface of the demister is spaced apart from the upper surface of the gas-liquid flow guiding device, and a turbulent flow zone is formed therebetween; The spraying device is used for spraying mineral oil toward the area where the demister is located.

2. A gas-liquid-solid separation device according to claim 1, characterized in that: The variable diameter cylinder of the gas-liquid diversion device is constructed as a cylinder structure expanding from bottom to top, the lower end of the variable diameter cylinder forms a gas-liquid inlet, the upper end of the variable diameter cylinder is fixedly connected to the tank body through an annular plate extending in the horizontal direction, and a plurality of jet holes are arranged on the annular plate.

3. A gas-liquid-solid separation device according to claim 2, characterized in that: The annular plate is provided with a plurality of rows of jet holes evenly arranged in the circumferential direction in the radial direction, and a guide plate is provided in the hole wall area of ​​the jet hole on the upper surface of the annular plate, and the guide plate extends obliquely toward the center line direction of the tank body.

4. A gas-liquid-solid separation device according to claim 3, characterized in that: The jet holes extend obliquely toward the center line of the tank body, the included angle between the extending direction of the jet holes and the vertical direction is 10°-20°, and the area of ​​all the jet holes on the annular plate accounts for 25%-40% of the area of ​​the annular plate.

5. The gas-liquid-solid separation device according to claim 1, characterized in that: A feed inlet is provided on the side wall of the tank body, and the feed inlet and the gas-liquid inlet of the gas-liquid guiding device are on the same horizontal plane.

6. The gas-liquid-solid separation device according to claim 1, characterized in that: The variable diameter cylinder of the gas-liquid flow guiding device comprises a cylindrical cylinder located at the lower side and a frustum cylinder located at the upper side of the cylindrical cylinder.

7. A gas-liquid-solid separation device according to claim 6, characterized in that: The lower side of the cylindrical body has a guide wall which is inclined inward and has an arc-shaped transition. The angle between the extension direction of the guide wall and the generatrix of the cylindrical body is 10°-20°.

8. The gas-liquid-solid separation device according to claim 6, characterized in that: The inner diameter of the cylindrical body accounts for 45%-55% of the inner diameter of the tank body, and the maximum inner diameter of the truncated cone body accounts for 75%-85% of the inner diameter of the tank body.

9. The gas-liquid-solid separation device according to claim 1, characterized in that: The spraying device comprises a spraying body and a fan blade rotatably connected to the spraying body, and the fan blade rotates around the spraying body under the action of a driving device.

10. The gas-liquid-solid separation device according to claim 9, characterized in that: An exhaust port is provided on the top of the tank body, and the exhaust port is connected to the compressor air intake pipeline. A detection device for detecting the powder content in the gas is provided on the compressor air intake pipeline. The control device controls the spraying device to spray mineral oil according to a set period based on a signal from the detection device.

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