CN218620666U

CN218620666U - Propylene polymerization device

Info

Publication number: CN218620666U
Application number: CN202222829671.1U
Authority: CN
Inventors: 尚明柱; 陈秀平; 李亚萍; 王斌; 朱飞飞
Original assignee: Zhejiang Satellite Energy Co ltd
Current assignee: Zhejiang Satellite Energy Co ltd
Priority date: 2022-10-26
Filing date: 2022-10-26
Publication date: 2023-03-14
Anticipated expiration: 2032-10-26

Abstract

The utility model provides a propylene polymerization device, this propylene polymerization device is including the prepolymerization reaction unit that connects gradually, liquid phase polymerization reaction unit, middle separation unit and gaseous phase polymerization reaction unit, middle separation unit is including parallelly connected first cyclone and the second cyclone that sets up, be equipped with the pipe connection between first cyclone and the second cyclone, gaseous phase polymerization reaction unit is including the horizontal reactor that connects gradually, third cyclone and knockout drum, horizontal reactor is equipped with material inlet, the gaseous phase export, liquid phase propylene entry, gaseous phase propylene entry and mixed material export, gaseous phase entry is established to third cyclone, gaseous phase export and polymer export, the knockout drum is equipped with material inlet, liquid phase export and gaseous phase export, the material inlet of middle separation unit passes through the pipeline with prepolymerization reaction unit discharge gate and communicates. The utility model discloses rational in infrastructure improves propylene polymerization efficiency, can satisfy the industrial production demand very much.

Description

Propylene polymerization device

Technical Field

The utility model relates to a polymerization facility, concretely relates to propylene polymerization facility belongs to macromolecular material technical field.

Background

The existing propylene polymerization device adopting a horizontal reactor generally adopts the modes of prepolymerization, liquid phase polymerization and gas phase polymerization to carry out propylene polymerization, wherein a mixed material obtained by the liquid phase polymerization contains polymer powder and one or more gas phases of propylene, hydrogen, ethylene and butylene.

Disclosure of Invention

Based on above background, the utility model aims to provide a propylene polymerization facility solves the problem in the background art.

In order to realize the purpose of the utility model, the utility model provides a following technical scheme:

the utility model provides a propylene polymerization device, this propylene polymerization device is including the prepolymerization reaction unit, liquid phase polymerization reaction unit, middle separation unit and the gas phase polymerization reaction unit that connect gradually, middle separation unit is including parallelly connected first cyclone and the second cyclone that sets up, be equipped with the pipe connection between first cyclone and the second cyclone, the gas phase polymerization reaction unit is including the horizontal reactor, third cyclone and the knockout drum that connect gradually, the horizontal reactor is equipped with material entry, gas phase export, liquid phase propylene entry, gas phase propylene entry and mixed material export, the third cyclone is equipped with gas phase entry, gas phase export and polymer export, the knockout drum is equipped with material entry, liquid phase export and gas phase export, the material entry and the liquid phase polymerization reaction unit discharge gate of first cyclone communicate through the pipeline, the bottom of first cyclone and second cyclone communicate with the material entry of horizontal reactor through the pipeline.

Preferably, the prepolymerization reaction unit comprises a propylene cooler and a prepolymerization reactor which are connected in sequence, and the prepolymerization reactor is connected with the liquid phase polymerization reaction unit.

Preferably, the liquid phase polymerization reaction unit comprises a loop reactor, the loop reactor is communicated with a prepolymerization reactor, and a cooling water jacket is arranged outside the loop reactor. The loop reactor has the functions of strong heat removal capacity and stable temperature control, and the cooling water jacket can remove the cooling water in the loop reactor.

Preferably, a material circulating pump is arranged at the bottom of the loop reactor. The material circulating pump can make the mixed material in the loop reactor in a circulating state to prevent precipitation.

Preferably, a gas phase outlet of the horizontal reactor is communicated with a gas phase inlet of a third cyclone separator, a gas phase outlet of the third cyclone separator is communicated with a material inlet of the liquid separation tank through a pipeline, and a condenser is arranged on the pipeline.

Preferably, the gas phase outlet of the liquid separation tank is communicated with the gas phase propylene inlet through a pipeline, and a circulating gas fan is arranged on the pipeline.

Preferably, the liquid phase outlet of the liquid separation tank is communicated with the liquid phase propylene inlet through a pipeline, and a propylene condensate pump is arranged on the pipeline.

Compared with the prior art, the utility model has the advantages of it is following:

the utility model discloses a propylene polymerization device, the mixed material that will come from liquid phase polymerization gets into middle separating element in reaction process, flash distillation takes place in first cyclone, then the separation of powder and unreacted propylene, the propylene gas after the separation goes circulation system after second cyclone separates once more, the powder that second cyclone separated out, get into gas phase polymerization unit, this propylene polymerization device is through setting up middle separating element, make the powder content among the mixed material that gets into gas phase polymerization unit improve, reduce the gaseous phase among the mixed material, thereby improve horizontal reactor's reaction efficiency, improve propylene polymerization efficiency.

Drawings

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

FIG. 1 is a schematic structural view of a propylene polymerization apparatus according to the present invention.

In the figure: 1. a prepolymerization reaction unit; 2. a liquid phase polymerization reaction unit; 3. an intermediate separation unit; 4. a gas phase polymerization reaction unit; 10. a propylene cooler; 11. a prepolymerization reactor; 20. a loop reactor; 21. a material circulating pump; 22. a cooling water jacket; 31. a first cyclone separator; 32. a second cyclone separator; 41. a horizontal reactor; 42. a third cyclone separator; 43. a condenser; 44. separating the liquid tank; 45. a propylene condensate pump; 46. and a circulating air fan.

Detailed Description

The technical solution of the present invention is further specifically described below by using specific embodiments and with reference to the accompanying drawings. It is to be understood that the practice of the present invention is not limited to the following examples, and that any modifications and/or changes in form made to the present invention are intended to fall within the scope of the present invention.

In the utility model, all parts and percentages are weight units, and the adopted equipment, raw materials and the like can be purchased from the market or commonly used in the field if not specified. The methods in the following examples are conventional in the art unless otherwise specified. Unless otherwise indicated, the components or devices in the following examples are all common standard components or components known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or through routine experimentation.

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. However, one or more embodiments may be practiced without these specific details by one of ordinary skill in the art.

The embodiment of the utility model discloses a propylene polymerization device, including prepolymerization reaction unit 1, liquid phase polymerization reaction unit 2, middle separator unit 3 and the gas phase polymerization reaction unit 4 that connect gradually.

The prepolymerization unit 1 comprises a propylene cooler 10 and a prepolymerization reactor 11 which are connected in sequence, the propylene cooler 10 is arranged to cool propylene to a required temperature, the prepolymerization reactor 11 is provided with a material inlet and a material outlet, the propylene cooler 10 is connected with the material inlet of the prepolymerization reactor 11, the propylene enters the prepolymerization reactor 11 from the material inlet of the prepolymerization reactor 11 after being cooled, and prepolymerization is carried out in the prepolymerization reactor 11.

The liquid phase polymerization reaction unit 2 comprises a loop reactor 20, a material outlet of the prepolymerization reactor 11 is connected with the loop reactor 20, a cooling water jacket 22 is arranged outside the loop reactor 20, the loop reactor 20 has the functions of strong heat removal capability and stable temperature control, a material circulating pump 21 is arranged at the bottom of the loop reactor 20 and is used for enabling mixed materials in the loop reactor 20 to be in a circulating state all the time and controlling the flow rate of the materials so as to prevent polymers in the mixed materials from settling, and the cooling water jacket 22 can withdraw cooling water from the loop reactor 20.

The intermediate separation unit 3 comprises a first cyclone separator 31 and a second cyclone separator 32 which are arranged in parallel, a pipeline is arranged between the first cyclone separator 31 and the second cyclone separator 32 for connection, a discharge hole of the loop reactor 20 is connected with a material inlet of the first cyclone separator 31, and the bottoms of the first cyclone separator 31 and the second cyclone separator 32 are communicated with a material inlet of the horizontal reactor 41 through pipelines.

The gas-phase polymerization reaction unit 4 comprises a horizontal reactor 41, a third cyclone separator 42 and a liquid separating tank 44 which are connected in sequence, wherein the horizontal reactor 41 is provided with a material inlet, a gas-phase outlet, a liquid-phase propylene inlet, a gas-phase propylene inlet and a mixed material outlet, the third cyclone separator 42 is provided with a gas-phase inlet, a gas-phase outlet and a polymer outlet, the liquid separating tank 44 is provided with a material inlet, a liquid-phase outlet and a gas-phase outlet, materials discharged by the middle separation unit 3 enter the horizontal reactor 41 in the gas-phase reaction unit, the gas-phase outlet of the horizontal reactor 41 is communicated with the gas-phase inlet of the third cyclone separator 42, the gas-phase outlet of the third cyclone separator 42 is communicated with the material inlet of the liquid separating tank 44 through a pipeline, the pipeline is provided with a condenser 43, the gas-phase outlet of the liquid separating tank 44 is communicated with the gas-phase propylene inlet through a pipeline, the pipeline is provided with a circulating gas blower 46, the liquid-phase outlet of the liquid separating tank 44 is communicated with the liquid-phase propylene inlet through a pipeline, and the pipeline is provided with a propylene condensate pump 45.

Taking the production of the EPDM as an example, the process flow of the propylene polymerization device is as follows:

1. prepolymerization reaction

Liquid phase propylene (25 ℃,4.0-4.5 MPag) at room temperature is cooled to 6-10 ℃ by a propylene cooler 1010, enters a prepolymerization reactor 11, and is subjected to prepolymerization reaction in the prepolymerization reactor 11.

The residence time of the catalyst in the prepolymerization reactor 11 is 12-18min, the prepolymerization reactor 11 is operated in a full kettle way, the catalyst and propylene are uniformly mixed by a stirrer, the reaction temperature is 16-24 ℃, and the pressure is 3.3-4.2MPag.

2. Liquid phase polymerization

The catalyst and unreacted propylene passing through the prepolymerization reactor 11 are introduced into the loop reactor 20 together with newly added liquid phase propylene.

At the same time, fresh liquid phase propylene, ethylene, hydrogen and butenes are also fed to the loop reactor 20 from the bottom.

The mole percent of ethylene to propylene in the feed is 1.0-4.0% and the ethylene content in the polymer is 2.0-4.8% wt. 1.0-12.0% by mole of butene and propylene, and 0.5-8.8% by weight of butene content in the polymer. The mole percentage of the hydrogen and the propylene is 0.05-1.5%, and the polymer melt mass flow rate is 2-20g/10min.

The temperature of the liquid phase polymerization reaction is controlled between 66 ℃ and 74 ℃, and the heat of polymerization is withdrawn by jacket cooling water of the loop reactor 20.

The loop reactor 20 is operated full, without the need for liquid level control. The feed leaving the loop reactor 20 contained 45-60% by weight of polymer, the remainder being propylene, hydrogen, ethylene and butene.

The loop reactor 20 keeps the flow velocity of the liquid phase mixture in the loop reactor 20 at 6-8 m/s through a material circulating pump 21 arranged at the bottom, so as to ensure that the polymer and the propylene are uniformly mixed;

3. intermediate separation reaction

The mixed material from the liquid phase polymerization unit 2 is introduced into the intermediate separation unit 3, and flash evaporation is carried out in the first cyclone 31, and then separation of the powder and unreacted propylene is carried out.

The separated propylene gas is separated again by the second cyclone 32 and then sent to the circulation system. The powder separated by the second cyclone 32 is introduced into the gas-phase polymerization reaction unit 4.

The pressure of the intermediate separation unit 3 is controlled between 2.3 and 2.7 MPag.

4. Gas phase polymerization

The material discharged from the middle separation unit 3 enters a horizontal reactor 41 in the gas phase reaction unit, the operation temperature is 62-90 ℃, and the operation pressure is 2.2-2.6MPag.

The gas phase propylene at the top of the reactor enters a propylene condenser 43 after the small-particle-size polymer is removed by a third cyclone separator 42, the heat of polymerization reaction is removed, the partially condensed liquid phase propylene and the supplemented liquid phase propylene and butylene return to the horizontal reactor 41 through a propylene condensate pump 45, and the partially uncondensed non-condensable gas and the ethylene and hydrogen enter the bottom of the horizontal reactor 41 through a circulating gas fan 46.

Controlling the mole percentage of ethylene and propylene in the gas phase at the top of the kettle to be 0.5-3.0%, and the ethylene content in the ternary random copolymerization polypropylene to be 1.8-4.5% by weight. The mole percentage of butene to propylene is 1.5-11.0%, the butene content in the ternary random copolymer polypropylene is 0.8-8.5% wt. The mol percentage of the hydrogen and the propylene is 0.03 to 1.2 percent, and the melt mass flow rate of the ternary random copolymerization polypropylene is 2 to 20g/10min.

The material level in the horizontal reactor 41 is controlled to be 50-70%, and the material level is controlled through a material outlet line at the bottom of the kettle. The feed leaving the horizontal reactor 41 contained 75-85% by weight of polymer, the remainder being propylene and hydrogen.

The horizontal reactor 41 is a horizontal stirred reactor containing an expansion section to ensure uniform mixing of the polymer and propylene.

The polymer passing through the horizontal reactor 41, 95% by weight, has a particle diameter of 20 mesh to 60 mesh. Wherein the polymer with the particle size of more than 40 meshes accounts for 60 percent, and the content of the polymer with the particle size of less than 100 meshes is less than 1 percent.

The polymer, after low-pressure flash and nitrogen displacement, had a volatile organic content of less than 0.01% by weight and could be used as such without further devolatilization.

The molecular weight distribution width of the polymer reaches 4-6. If the loop reactor 20 and the horizontal reactor 41 employ differential hydrogen addition and melt mass flow rate control, the final polymer molecular weight distribution width can be increased to over 6.

When a special catalyst system is used, the high-flow ternary random copolymerization polypropylene with the melt mass flow rate of 20-30g/10min can be produced. The method is used for the field of rapid injection molding or thin-wall injection molding.

The ternary random copolymer polypropylene obtained by the above method has xylene soluble content of less than 2.8% by weight, which is superior to national standard, and can be used in the field of food packaging.

The ternary random copolymerization polypropylene obtained by the method has the polymer melting point of lower than 120 ℃, 45 ℃ lower than that of common homopolymerization polypropylene, and the downstream processing temperature can be reduced by at least 30 ℃. Due to the addition of ethylene and butylene, the crystallinity of the polymer is less than half of that of homopolymerized polypropylene, and the polypropylene has excellent barrier property and compatibility, and is particularly suitable for being used as an intermediate layer of a CPP cast film packaging material.

The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of the embodiments are only used to help understand the method and its core ideas of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.

Claims

1. A propylene polymerization apparatus characterized in that: the propylene polymerization device comprises a prepolymerization reaction unit (1), a liquid-phase polymerization reaction unit (2), an intermediate separation unit (3) and a gas-phase polymerization reaction unit (4) which are sequentially connected, wherein the intermediate separation unit (3) comprises a first cyclone separator (31) and a second cyclone separator (32) which are arranged in parallel, a pipeline is arranged between the first cyclone separator (31) and the second cyclone separator (32) for connection, the gas-phase polymerization reaction unit (4) comprises a horizontal reactor (41), a third cyclone separator (42) and a liquid separation tank (44) which are sequentially connected, the horizontal reactor (41) is provided with a material inlet, a gas-phase outlet, a liquid-phase propylene inlet, a gas-phase propylene inlet and a mixed material outlet, the third cyclone separator (42) is provided with a gas-phase inlet, a gas-phase outlet and a polymer outlet, the liquid separation tank (44) is provided with a material inlet, a liquid-phase outlet and a gas-phase outlet, the material inlet of the intermediate separation unit (3) is communicated with the discharge hole of the prepolymerization reaction unit (1) through a pipeline, and the bottoms of the first cyclone separator (31) and the second cyclone separator (32) are communicated with the reaction unit (41) through a pipeline.

2. The propylene polymerization apparatus according to claim 1, wherein: the prepolymerization unit (1) comprises a propylene cooler (10) and a prepolymerization reactor (11) which are sequentially connected, and the prepolymerization reactor (11) is connected with the liquid phase polymerization unit (2).

3. The propylene polymerization apparatus according to claim 1, wherein: the liquid phase polymerization reaction unit (2) comprises a loop reactor (20), the loop reactor is communicated with a prepolymerization reactor, and a cooling water jacket (22) is arranged outside the loop reactor (20).

4. The propylene polymerization apparatus according to claim 3, wherein: the bottom of the loop reactor (20) is provided with a material circulating pump (21).

5. The propylene polymerization apparatus according to claim 1, wherein: and a gas-phase outlet of the horizontal reactor (41) is communicated with a gas-phase inlet of a third cyclone separator (42), a gas-phase outlet of the third cyclone separator (42) is communicated with a material inlet of a liquid separating tank (44) through a pipeline, and a condenser (43) is arranged on the pipeline.

6. The propylene polymerization apparatus according to claim 5, wherein: and a gas phase outlet of the liquid separation tank (44) is communicated with a gas phase propylene inlet through a pipeline, and a circulating gas fan (46) is arranged on the pipeline.

7. The propylene polymerization apparatus according to claim 6, wherein: and a liquid phase outlet of the liquid separation tank (44) is communicated with a liquid phase propylene inlet through a pipeline, and a propylene condensate pump (45) is arranged on the pipeline.