公开(公告)号：US20250025822A1

公开(公告)日：2025-01-23

申请号：US18709439

申请日：2022-10-31

Applicant: ExxonMobil Chemical Patents Inc.

Inventor： Aaron C. MCGINNIS ,  Michael G. TRIBO ,  Michael D. LUCAS ,  Richard P. CUTTING ,  Benjamin J. OHRAN

IPC: B01D53/00 ,  B01J8/00

Abstract: Processes for venting gas phase olefin polymerization systems are provided. A portion of the reactor overhead can be withdrawn from the reactor to a vent column and contacted with a liquid stripping medium (L) within the vent column to remove at least a portion of the olefin monomer to produce a vent column overhead (G) and a vent column bottoms; recycling the vent column bottoms (rich in the olefin monomer and lean in the carrier gas) to the reactor; determining a L*N to C*G ratio, wherein L is total liquid stripping medium flow to the vent column, N is carrier gas concentration in the reactor overhead, C is the monomer concentration in the reactor overhead, and G is the vent column overhead gas flow. One or more of these flow streams (L, N, C, G) can then be controlled based on the calculated L*N to C*G ratio.

公开(公告)号：US20240043581A1

公开(公告)日：2024-02-08

申请号：US18264515

申请日：2022-02-25

Applicant: ExxonMobil Chemical Patents Inc.

Inventor： Nathaniel B. GUY ,  Stacy N. OLALEYE ,  Michael D. LUCAS ,  Handel D. BENNETT ,  David T. LAKIN ,  Benjamin J. OHRAN ,  Aaron C. MCGINNIS

IPC: C08F10/02 ,  B01J8/18 ,  B01J8/00

CPC classification number: C08F10/02 ,  B01J8/1827 ,  B01J8/1872 ,  B01J8/007 ,  B01J8/1809 ,  C08F2400/02 ,  B01J2208/00761 ,  B01J2208/00769 ,  B01J2219/00164 ,  B01J2219/00162

Abstract: A process for producing an olefin polymer employs a gas phase polymerization reactor in fluid communication with a vent column and a product discharge system. The discharge system can include first and second pairs of lock hoppers, where each pair includes an upstream lock hopper connected by a valve to the reactor and a downstream lock hopper connected by a valve to the upstream lock hopper and by a further valve to a product recovery system, and where a first cross-tie can be provided between the upstream lock hoppers of the first and second pairs of lock hoppers and a second cross-tie can be provided between the downstream lock hoppers of the first and second pairs of lock hoppers. Upon reaching the vent column's maximum removal capacity, additional gas can be removed from the reactor by reducing the frequency of opening the second cross-tie between the downstream lock hoppers.