Apparatus and process for the gas-phase polymerization

Patent metadata

Field	Value
Publication number	US-12337310-B2
Application number	US-202017783170-A
Country	US
Kind code	B2
Filing date	Dec 9, 2020
Priority date	Dec 11, 2019
Publication date	Jun 24, 2025
Grant date	Jun 24, 2025

Abstract

An apparatus for carrying out a gas-phase olefin polymerization having a first polymerization zone having a cylindrical segment of diameter D01, a second polymerization zone having a cylindrical upper part of diameter D05 and a cylindrical lower part of diameter D06, a separation zone of diameter D04, a first connecting element of diameter D03, which is a bend of radius R03 or has a bend part of radius R03, a gas recycle line of diameter D08, a transition segment of diameter D02, and a second connecting element of a diameter D09, which is a bend or has a bend part, wherein the ratio D04 to D05 is 1.0 to 1.5, the ratio D05 to D06 is 1.2 to 2, the ratio R03 to D03 is 1 to 6, the ratio D03 to D01 is 0.3 to 0.85, and the ratio D08 to D02 is 1.0 to 2.2.

First claim

The invention claimed is:

1. An apparatus for carrying out a gas-phase olefin polymerization comprising
a first polymerization zone, adapted and arranged for growing polymer particles to flow upward under fast fluidization or transport conditions, comprising a cylindrical segment having a diameter D01;
a second polymerization zone, adapted and arranged for the growing polymer particles to flow downward, comprising a cylindrical upper part having a diameter D05 and a cylindrical lower part having a diameter D06;
a gas/solid separation zone of a cylindrical shape having a diameter D04, adapted and arranged for separating growing polymer particles from a gas flow, which is arranged on top of the upper part of the second polymerization zone and is directly connected to the upper part of the second polymerization zone;
a tubular first connecting element having a diameter D03, adapted and arranged for connecting the cylindrical segment of the first polymerization zone to the gas/solid separation zone;
a tubular gas recycle line having a diameter D08, adapted and arranged for connecting the gas/solid separation zone to the first polymerization zone;
a tubular transition segment having a diameter D02, arranged between the gas recycle line and the cylindrical segment of the first polymerization zone; and
a tubular second connecting element having a diameter D09, adapted and arranged for connecting the lower part of the second polymerization zone to the transition segment;
wherein the gas recycle line is equipped with a compressor, adapted and arranged for circulating gas in the gas recycle line, and a heat exchanger, adapted and arranged for removing heat from the gas flowing in the gas recycle line;
wherein the ratio of D04 to D05 is from 1.0 to 1.5 and the ratio of D05 to D06 is from 1.2 to 2;
wherein the first connecting element is a bend having a radius R03 or is a tubular element comprising one or more bend parts having one or more radiuses R03 and one or more linear parts, the ratio of R03 to D03 is from 1 to 6, and the ratio of D03 to D01 is from 0.3 to 0.85;
wherein the first connecting element comprises a connecting piece, the first connecting element and the gas/solid separation zone are connected by the connecting piece, and the connection of the connecting piece to the gas/solid separation zone is tangential and has an inclination, so that the central axis of the connecting piece and the horizontal form, an angle A16 in the range from 0° to 40°;
wherein the transition segment is a bend or a tubular element comprising one or more bend parts and one or more linear parts and the ratio of D08 to D02 is 1.0 to 2.2; and
wherein the second connecting element is a bend or a tubular element comprising one or more bend parts and one or more linear parts.

2. The apparatus of claim 1 , wherein the central axis of the second connecting element at the position where the second connecting element is connected to the transition segment and the horizontal form an angle A02 in the range from 0° to 40°.

3. The apparatus of claim 1 , wherein the apparatus further comprises a line for feeding a barrier gas, a barrier liquid, or a combined gas/liquid barrier into the upper part of the second polymerization zone.

4. The apparatus of claim 1 , wherein the apparatus further comprises a line for feeding a transport gas into an upper part of the second connecting element.

5. The apparatus of claim 4 , wherein the second connecting element is provided with a gas distribution grid extending from the upper end of the second connecting element for an angle A09 of at least 50° along the bending of the second connecting element.

6. The apparatus of claim 1 , wherein the second polymerization zone comprises a throttling valve, and the apparatus further comprises a line for feeding a dosing gas into the lower part of the second polymerization zone at one or more positions above the throttling valve.

7. The apparatus of claim 1 , wherein the compressor is a centrifugal compressor comprising variable guide vanes, and the gas recycle line is further equipped with a butterfly valve.

8. The apparatus of claim 7 , wherein the variable guide vanes are arranged upstream of the centrifugal compressor, and the butterfly valve is arranged downstream of the centrifugal compressor.

9. The apparatus of claim 1 , wherein the gas/solid separation zone has a height H04, and the ratio of H04 to D04 is 2.5 to 4.5.

10. The apparatus of claim 1 , wherein the upper part of the second polymerization zone has a height H05, and the ratio of H05 to D05 is 2 to 4.

11. The apparatus of claim 1 , wherein the apparatus is part of a series of polymerization reactors.

12. A process for carrying out a gas-phase olefin polymerization in the apparatus of claim 1 at temperatures of from 20° C. to 200° C. and pressures of from 0.5 MPa to 10 MPa, in the presence of a polymerization catalyst, comprising the steps of:
(a) feeding one or more olefins into the apparatus,
(b) contacting the olefins and the polymerization catalyst under reaction conditions, and
(c) discharging the polymer product from the apparatus,
wherein the growing polymer particles
(i) flow upward through the first polymerization zone under fast fluidization or transport conditions,
(ii) leave the first polymerization zone,
(iii) pass through the gas/solid separation zone,
(iv) enter the second polymerization zone,
(v) flow downward under the action of gravity,
(vi) leave the second polymerization zone, and
(vii) are reintroduced, at least partially, into the first polymerization zone,
thereby establishing a circulation of polymer between the first polymerization zone and the second polymerization zone, wherein the second polymerization zone comprises a bed of densified polymer particles.

13. The process of claim 12 , wherein introducing a gas or liquid into the second polymerization zone via a feeding line prevents completely or partially the gas mixture in the first polymerization zone from entering the upper part of the second polymerization zone, and the gas mixture in the second polymerization zone differs from the gas mixture in the first polymerization zone.

14. The process of claim 13 , wherein the surface of the bed of densified polymer particles is located in the upper part of the second polymerization zone.

15. The process of claim 12 , wherein the polymerization is a homopolymerization of ethylene, or a copolymerization of ethylene and one or more other olefins selected from the group consisting of 1-butene, 1-hexene, and 1-octene, a homopolymerization of propylene, or a copolymerization of propylene and one or more other olefins selected from the group consisting of ethylene, 1-butene and 1-hexene.

16. The process of claim 12 , wherein the central axis of the second connecting element at the position where the second connecting element is connected to the transition segment and the horizontal form an angle A02 in the range from 0° to 40°.

17. The process of claim 12 , wherein the apparatus further comprises a line for feeding a transport gas into an upper part of the second connecting element, and the second connecting element is provided with a gas distribution grid extending from the upper end of the second connecting element for an angle A09 of at least 50° along the bending of the second connecting element.

18. The process of claim 12 , wherein the gas/solid separation zone has a height H04, and the ratio of H04 to D04 is 2.5 to 4.5.

19. The process of claim 12 , wherein the upper part of the secon

Assignees

• Basell Polyolefine Gmbh

Inventors

• Mei Giulia
• Penzo Giuseppe
• Rinaldi Riccardo
• Azzarello Emanuele
• Pesare Rosario

Classifications

• B01J19/2435 Primary

  Loop-type reactors · CPC title

• B01J8/0055 Primary

  using cyclones · CPC title

• C08F10/00

  Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond · CPC title

• B01J8/26

  with two or more fluidised beds, e.g. reactor and regeneration installations · CPC title

• B01J8/1863

  followed by a downward movement outside the reactor and subsequently re-entering it · CPC title