Treatment device for enriching ethane in olefin polymerization

Abstract

The utility model provides a treatment device for enriching ethane in olefin polymerization, which solves the problem that a shunting system cannot realize flow integrated regulation and the like, and comprises a reaction unit, the reaction unit is connected with a devolatilization unit, the devolatilization unit is connected with the reaction unit through a monomer recovery device, the monomer recovery device is provided with a shunting assembly, and the shunting assembly is connected with the devolatilization unit. The monomer recovery device is provided with a backflow assembly opposite to the flow dividing assembly. The adjusting device has the advantages of high adjusting precision, good structural stability and the like.

Description

Technical Field

[0001] The utility model belongs to the technical field of ethane treatment, and particularly relates to a treatment device for enriching ethane in olefin polymerization. Background Art

[0002] During the olefin polymerization process, a large amount of exhaust gas is generated during production, mainly including substances such as ethylene, ethane, butene, hexene, octene, and hydrogen. To improve the utilization rate of raw materials, reduce costs and increase efficiency, a complete set of recovery devices is required for the above exhaust gas. Hydrocarbons with relatively high boiling points such as C2 and above are recycled back into their respective storage tanks for repeated use, and non-condensable gases such as hydrogen are transported to the torch for combustion treatment. Polymer-grade ethylene (99.95%) contains approximately less than 500 ppm of ethane. As the reaction cycle progresses, ethane in the entire system will gradually accumulate, resulting in a decrease in ethylene purity and thus reducing the polymerization efficiency. In addition, due to the increase in exhaust gas volume, the conventional shunt system cannot meet its integrated control requirements.

[0003] In order to solve the deficiencies of the existing technology, people have conducted long-term explorations and proposed various solutions. For example, a Chinese patent document discloses an ethane recovery tank [202010618675.8], which includes a recovery tank with a main inlet and a main outlet. A purification tank is installed on one side of the recovery tank. The purification tank is provided with a secondary inlet, an inlet pump is installed on one side of the secondary inlet, a gas guide pipe is installed on the other side of the secondary inlet, several branch pipes are installed on the gas guide pipe, several branch tubes are installed on the branch pipes, a filter pool is arranged in the purification tank, the branch tubes are installed in the filter pool, the purification tank is provided with a secondary outlet, an air suction pump is installed on one side of the secondary outlet, and the air suction pump is installed on one side of the main inlet. A filter pool is arranged in the purification tank, the mixed gas is discharged into the gas guide pipe through the inlet pump, several branch pipes are connected to the gas guide pipe, and several branch tubes are connected to the branch pipes.

[0004] The above solution solves the problem of ethane recovery and treatment to a certain extent, but there are still many deficiencies in this solution, such as the problem of inconvenient integrated distribution management of exhaust gas. Summary of the Invention

[0005] The purpose of the utility model is to solve the above problems and provide a treatment device for enriching ethane in olefin polymerization, which is reasonably designed and convenient for integrated management of the exhaust gas of olefin polymerization.

[0006] To achieve the above purpose, the utility model adopts the following technical solutions: A treatment device for enriching ethane in olefin polymerization includes a reaction unit, the reaction unit is connected to a devolatilization unit, the devolatilization unit is connected to the reaction unit through a monomer recovery device, a shunt assembly is installed on the monomer recovery device, and a reflux assembly opposite to the shunt assembly is equipped on the monomer recovery device.

[0007] In the above-mentioned processing device for enriching ethane in olefin polymerization, the monomer recovery device includes a recovery tank. A number of gas outlets are provided at the upper end of the recovery tank, and an air inlet is provided at the lower end of the recovery tank. The interior of the recovery tank is divided into an air inlet chamber and an air outlet chamber by a partition.

[0008] In the above-mentioned processing device for enriching ethane in olefin polymerization, the flow splitting assembly includes an air inlet adjustment assembly arranged between the partition and the air inlet chamber, and an air outlet adjustment assembly is arranged between the partition and the air outlet chamber.

[0009] In the above-mentioned processing device for enriching ethane in olefin polymerization, the air inlet adjustment assembly includes an adjustment motor installed at the lower end of the recovery tank. The output end of the adjustment motor is connected to an adjustment rod extending along the central axis of the recovery tank. The upper end of the adjustment rod is rotatably connected to the partition. A number of air inlet grooves that are centrosymmetric and radially arranged are formed on the partition. The adjustment rod is connected to an adjustment piece that fits against the lower end of the partition. Adjustment openings that are offset or overlapped with the air inlet grooves are formed on the adjustment piece.

[0010] In the above-mentioned processing device for enriching ethane in olefin polymerization, the air outlet adjustment assembly includes a valve piece arranged in the air outlet chamber and slidingly fitted against the inner wall of the recovery tank. Valve openings that are offset or overlapped with the gas outlets are formed on the valve piece. An opening and closing motor is installed at the upper end of the recovery tank. The output end of the opening and closing motor is meshed and driven with an adjustment rack on the side of the valve piece through an adjustment gear.

[0011] In the above-mentioned processing device for enriching ethane in olefin polymerization, flow sensors corresponding to the gas outlets and the air inlet one by one are installed in the recovery tank.

[0012] In the above-mentioned processing device for enriching ethane in olefin polymerization, a pressure relief port is installed at the top of the recovery tank, and the pressure relief port is equipped with an electromagnetic on-off valve.

[0013] In the above-mentioned processing device for enriching ethane in olefin polymerization, the reflux assembly includes a reflux pipe connected to the gas outlet, and the reflux pipe is equipped with a check valve.

[0014] In the above-mentioned processing device for enriching ethane in olefin polymerization, temperature sensors are respectively installed in the air inlet chamber and the air outlet chamber in the recovery tank.

[0015] In the above-mentioned processing device for enriching ethane in olefin polymerization, the inner side of the recovery tank is coated with a fluorocarbon coating.

[0016] Compared with the existing technology, the advantages of the present utility model are as follows: The monomer recovery device is internally provided with a flow splitting component for exhaust gas splitting, so as to flexibly adjust the internal flow rate of the reflux component; The intake and outlet regulating components in the flow splitting component are relatively independent, and the equipped valve body structure adjusts the overall flow rate and the flow rate of each outlet; In the reflux component, the reflux pipe cooperates with the check valve to prevent gas from flowing back and improve the overall safety of the treatment system. Description of the Drawings

[0017] Figure 1 is the structural block diagram of the present utility model;

[0018] Figure 2 is the structural schematic diagram of the monomer recovery device of the present utility model;

[0019] Figure 3 is another structural schematic diagram of the monomer recovery device of the present utility model;

[0020] Figure 4 is the structural sectional view of the monomer recovery device of the present utility model;

[0021] Figure 5 is the structural schematic diagram of the partition board of the present utility model;

[0022] In the figure, monomer recovery device 1, recovery tank 11, outlet 12, inlet 13, partition board 14, intake cavity 15, outlet cavity 16, pressure relief port 17, electromagnetic on-off valve 18, regulating motor 21, regulating rod 22, intake groove 23, regulating piece 24, regulating port 25, valve piece 26, valve port 27, opening and closing motor 28, reflux component 3, reflux pipe 31, check valve 32, reaction unit 4, devolatilization unit 5, intake regulating component 6, outlet regulating component 7. Detailed Embodiments

[0023] The following further elaborates on the present utility model in detail in conjunction with the drawings and specific embodiments.

[0024] As Figures 1-5 shown, a treatment device for enriching ethane in olefin polymerization includes a reaction unit 4, the reaction unit 4 is connected to a devolatilization unit 5, and the copolymer solution obtained by polymerization in the reaction unit 4 passes through the devolatilization unit 5 to separate the POE product from the exhaust gas. The devolatilization unit 5 is connected to the reaction unit 4 through a monomer recovery device 1 to recover the reaction solvent, octene, and most of the ethylene. The monomer recovery device 1 is equipped with a flow splitting component to adjust and distribute the flow rate of the exhaust gas. The monomer recovery device 1 is equipped with a reflux component 3 opposite to the flow splitting component, and part of the gas is recovered by the reflux component 3, and a small part of combustible gases such as ethylene, ethane, and hydrogen are transported to the torch for combustion treatment.

[0025] Specifically, the monomer recovery device 1 includes a recovery tank 11 made of stainless steel. A number of air outlets 12 are provided at the upper end of the recovery tank 11, and an air inlet 13 is provided at the lower end of the recovery tank 11. The inside of the recovery tank 11 is divided into an air inlet chamber 15 and an air outlet chamber 16 by a partition 14. The flow splitting assembly mainly adjusts the flow rates of the air outlets 12 and the partition 14.

[0026] In-depth, different from the conventional fixed flow channel structure, in this embodiment, the flow splitting assembly includes an air inlet adjustment assembly 6 provided between the partition 14 and the air inlet chamber 15, and an air outlet adjustment assembly 7 is provided between the partition 14 and the air outlet chamber 16. The air inlet adjustment assembly 6 and the air outlet adjustment assembly 7 are relatively independent, and can completely close the internal flow channels of the monomer recovery device 1 or control the flow rates of each flow channel.

[0027] In addition, the air inlet adjustment assembly 6 controls the gas flow in the air inlet chamber 15 and the air outlet chamber 16, including an adjustment motor 21 installed at the lower end of the recovery tank 11. The output end of the adjustment motor 21 is connected to an adjustment rod 22 extending along the central axis of the recovery tank 11. The upper end of the adjustment rod 22 is rotatably connected to the partition 14. A number of air inlet slots 23 that are centrosymmetric and radially arranged are formed on the partition 14. The adjustment rod 22 is connected to an adjustment piece 24 that fits against the lower end of the partition 14. An adjustment opening 25 that is offset or overlapped with the air inlet slots 23 is formed on the adjustment piece 24. When the adjustment motor 21 drives the adjustment rod 22 and the adjustment piece 24 to rotate, the flux of the air inlet slots 23 is also adjusted accordingly.

[0028] At the same time, in order to improve the adjustment accuracy of the reflux assembly 3, the air outlet adjustment assembly 7 includes a valve piece 26 that is arranged in the air outlet chamber 16 and slides and fits against the inner wall of the recovery tank 11. A valve opening 27 that is offset or overlapped with the air outlet 12 is formed on the valve piece 26. The valve piece 26 adjusts the flux of the valve opening 27 in a vertical lifting manner. An opening and closing motor 28 is installed at the upper end of the recovery tank 11. The output end of the opening and closing motor 28 is in meshing transmission with an adjustment rack on the side of the valve piece 26 through an adjustment gear. Each opening and closing motor 28 is independently driven and controlled, and drives the valve piece 26 to lift by a gear-rack drive structure.

[0029] Visibly, a flow sensor corresponding to the air outlet 12 and the air inlet 13 one by one is installed in the recovery tank 11. The flow sensor cooperates with the flow splitting assembly to achieve flow feedback adjustment, thereby improving the control accuracy of the reflux assembly 3 for the hydrocarbon material cycle.

[0030] Obviously, a pressure relief port 17 is installed at the top of the recovery tank 11. The pressure relief port 17 is equipped with an electromagnetic on-off valve 18. When the input discharge gas of the monomer recovery device 1 exceeds the rated flow rate, the electromagnetic on-off valve 18 opens and rapid pressure relief is carried out through the pressure relief port 17.

[0031] Preferably, the reflux assembly 3 includes a reflux pipe 31 connected to the air outlet 12, and the reflux pipe 31 is equipped with a one-way valve 32. The reflux pipe 31 is connected to an external reactor to separate and recover the reaction solvent, octene, and most of the ethylene therein.

[0032] Obviously, temperature sensors are respectively installed in the air inlet cavity 15 and the air outlet cavity 16 of the recovery tank 11, and the inner side of the recovery tank 11 is coated with a fluorocarbon coating. The overall recovery tank 11 has good high-temperature resistance, and the temperature sensors therein monitor the temperature of the exhaust gas from the devolatilization unit in real time.

[0033] In summary, the principle of this embodiment is that the monomer recovery device 1 is internally provided with a shunt assembly to shunt the exhaust gas from the devolatilization unit, thereby precisely adjusting the internal flow rate of the reflux assembly 3 to ensure the stable operation of the reaction unit for the exhaust gas treatment. The shunt assembly takes into account both flow rate adjustment and exhaust gas distribution, and has a high adjustment flexibility.

[0034] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar methods for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0035] Although terms such as monomer recovery device 1, recovery tank 11, air outlet 12, air inlet 13, partition 14, air inlet cavity 15, air outlet cavity 16, pressure relief port 17, electromagnetic on-off valve 18, adjustment motor 21, adjustment rod 22, air inlet groove 23, adjustment piece 24, adjustment port 25, valve piece 26, valve port 27, opening and closing motor 28, reflux assembly 3, reflux pipe 31, one-way valve 32, reaction unit 4, devolatilization unit 5, air inlet adjustment assembly 6, air outlet adjustment assembly 7 are used more frequently in this article, the possibility of using other terms is not excluded. The use of these terms is only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. A treatment device for enriching ethane in olefin polymerization, comprising a reaction unit (4), wherein the reaction unit (4) is connected to a devolatilization unit (5), and the devolatilization unit is connected to the reaction unit (4) through a monomer recovery device (1), characterized in that, The monomer recovery device (1) described above is equipped with a flow splitting component, and the monomer recovery device (1) is equipped with a reflux component (3) opposite to the flow splitting component.

2. The treatment device for enriching ethane in olefin polymerization according to claim 1, characterized in that, The monomer recovery device (1) includes a recovery tank (11). A number of gas outlets (12) are provided at the upper end of the recovery tank (11), an air inlet (13) is provided at the lower end of the recovery tank (11), and the interior of the recovery tank (11) is divided into an air inlet chamber (15) and an air outlet chamber (16) by a partition plate (14).

3. The processing device for enriching ethane in olefin polymerization according to claim 2, wherein, The flow splitting component includes an air inlet adjustment component (6) arranged between the partition plate (14) and the air inlet chamber (15), and an air outlet adjustment component (7) is arranged between the partition plate (14) and the air outlet chamber (16).

4. A treatment device for enriching ethane in olefin polymerization according to claim 3, characterized in that, The air inlet adjustment component (6) includes an adjustment motor (21) installed at the lower end of the recovery tank (11). The output end of the adjustment motor (21) is connected to an adjustment rod (22) extending along the central axis of the recovery tank (11). The upper end of the adjustment rod (22) is rotatably connected to the partition plate (14). A number of air inlet grooves (23) that are centrosymmetric and radially arranged are formed on the partition plate (14). The adjustment rod (22) is connected to an adjustment piece (24) that fits against the lower end of the partition plate (14), and an adjustment opening (25) that is misaligned or overlapped with the air inlet grooves (23) is formed on the adjustment piece (24).

5. The treatment device for enriching ethane in olefin polymerization according to claim 3, characterized in that, The air outlet adjustment component (7) includes a valve piece (26) arranged in the air outlet chamber (16) and slidingly fitted against the inner wall of the recovery tank (11). A valve opening (27) that is misaligned or overlapped with the gas outlets (12) is formed on the valve piece (26). An opening and closing motor (28) is installed at the upper end of the recovery tank (11), and the output end of the opening and closing motor (28) is in meshing transmission with an adjustment rack on the side of the valve piece (26) through an adjustment gear.

6. The processing device for enriching ethane in olefin polymerization according to claim 2, wherein, Flow sensors corresponding to the gas outlets (12) and the air inlets (13) one by one are installed in the recovery tank (11).

7. A treatment device for enriching ethane in olefin polymerization according to claim 2, characterized in that, A pressure relief port (17) is installed at the top of the recovery tank (11), and the pressure relief port (17) is equipped with an electromagnetic on-off valve (18).

8. The processing device for enriching ethane in olefin polymerization according to claim 2, characterized in that The reflux component (3) includes a reflux pipe (31) connected to the gas outlets (12), and the reflux pipe (31) is equipped with a check valve (32).

9. The treatment device for enriching ethane in olefin polymerization according to claim 2, characterized in that, Temperature sensors are respectively installed in the air inlet chamber (15) and the air outlet chamber (16) in the recovery tank (11).

10. The processing device for enriching ethane in olefin polymerization according to claim 2, characterized in that, The inner side of the recovery tank (11) is coated with a fluorocarbon coating.

Images