Method and apparatus for minimizing polymer agglomerate or lump formation in a gas-phase polypropylene polymerization reactor

• US 4,921,919 A
• Filed: 06/03/1988
• Issued: 05/01/1990
• Est. Priority Date: 12/10/1985
• Status: Expired due to Term

• Current Assignee: Amoco Corporation (BP PLC)
• Original Assignee: Amoco Corporation (BP PLC)
• Inventors: Stevens, Jack F., Lin, Chi-Hung, Rose, Philip M., Tovrog, Benjamin S.
• Primary Examiner(s): Smith, Edward J.
• Application Number:
  US07/202,092
• Time in Patent Office: 697 Days
• Field of Search: 526/88
• US Class Current: 526/88
• CPC Class Codes: B01J 19/002 Avoiding undesirable reactions or side-effects, e.g. avoiding explosions, or improving the yield by suppressing side-reactions
• CPC Class Codes: B01J 19/18 Stationary reactors having moving elements inside B01J19/08, B01J19/26 take precedence
• CPC Class Codes: B01J 2208/00 Processes carried out in the presence of solid particles; Reactors therefor
• CPC Class Codes: B01J 2219/00184 controlling the weight of reactants in the reactor vessel
• CPC Class Codes: B01J 2219/182 horizontal
• CPC Class Codes: B01J 2219/1943 cylindrical
• CPC Class Codes: B01J 8/36 with fluidised bed through which there is an essentially horizontal flow of particles
• CPC Class Codes: B01J 8/382 with a rotatable device only
• CPC Class Codes: C08F 10/00 Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
• CPC Class Codes: C08F 2/34 Polymerisation in gaseous state
• CPC Class Codes: C08F 2400/02 Control or adjustment of polymerization parameters
• CPC Class Codes: Y10S 526/901 Monomer polymerized in vapor state in presence of transition metal containing catalyst
• CPC Class Codes: Y10S 526/919 Catalyst injection technique in addition polymerization processes

Abstract

The process and the system are used for carrying out the quench-cooled, vapor-phase polymerization of olefin monomer in a horizontally disposed reactor vessel which comprises contacting olefin monomer, or a mixture of olefin monomers, with a polymerization catalyst system in the presence of hydrogen in the reactor vessel to form a polymer product. The improvement comprises introducing a titanium-containing catalyst component of the catalyst system into the top side of the reactor vessel at a point adjacent to the upstream end of the reactor vessel and introducing a cocatalyst plus modifer component of the catalyst system into the top side of the reactor vessel at a distance, downstream of the point of introduction of the titanium-containing catalyst component, which is equal to 25% of the inside diameter of the reactor vessel.

Claims

1. In a process for quench-cooled, vapor-phase polymerization of olefin monomer in a horizontally disposed reactor vessel comprising contacting olefin monomer, or a mixture of olefin monomers, with a polymerization catalyst system in the presence of hydrogen in a reactor vessel to form a polymer product, the improvement comprising introducing a high activity titanium-containing catalyst component of the catalyst system into the top side of the reactor vessel onto a polymer bed at a point as close as possible to the upstream end of the reactor vessel, mixing the catalyst component with the polymer product in the reactor vessel and introducing a cocatalyst plus modifier component of the catalyst system into the top side of the reactor vessel onto the polymer bed at a distance downstream of the point of introduction of the catalyst, the downstream distance being equal to at least 25% of the inside diameter of the reactor vessel.

2. The process of claim 1 wherein the downstream distance is equal to 30% of the inside diameter of the reactor vessel.

3. The process of claim 1 wherein the downstream distance is equal to 80% of the inside diameter of the reactor vessel.