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 A portion of the reactor overhead can be withdrawn from the reactor to a vent column and contacted with a liquid stripping medium (L) within the vent column to remove at least a portion of the olefin monomer to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.

公开(公告)号：US20220119563A1

公开(公告)日：2022-04-21

申请号：US17310700

申请日：2020-03-04

Applicant: ExxonMobil Chemical Patents Inc.

Inventor： Bruce J. SAVATSKY ,  Brian R. GREENHALGH ,  Joseph A. MOEBUS ,  Aaron C. MCGINNIS ,  Ryan W. IMPELMAN ,  Anne A. BERNARD-BRUNEL

IPC: C08F210/06 ,  C08F210/08 ,  C08F210/16 ,  C08F110/02 ,  B01J8/18 ,  B01J19/00 ,  B01J19/24

Abstract: The present disclosure relates to processes for production of polyolefins from olefin monomer(s) in a gas phase reactor using condensing agent(s) (CAs), and in particular relates to controlling condensed phase cooling in a gas phase reactor used to polymerize olefin monomer(s). The method may include introducing first and second condensing agent(s) into the reactor at ratio(s) determined by ascertaining a stick limit for the first condensing agent, calculating an equivalence factor relating the first and second condensing agents, ascertaining total allowable condensing agent, and calculating amount of the first condensing agent removed and replaced by the second condensing agent. The method may further include calculating the dew point limit of a gas phase composition including olefin monomer(s) as well as the first and second condensing agents; and determining if introducing a mixture comprising the olefin monomer(s) and the condensing agent composition would exceed the calculated dew point limit.

公开(公告)号：US20220098332A1

公开(公告)日：2022-03-31

申请号：US17310699

申请日：2020-03-04

Applicant: ExxonMobil Chemical Patents Inc.

Inventor： Bruce J. SAVATSKY ,  Brian R. GREENHALGH ,  Joseph A. MOEBUS ,  Aaron C. MCGINNIS ,  Ryan W. IMPELMAN ,  Anne A. BERNARD-BRUNEL

IPC: C08F2/34

Abstract: This disclosure relates to processes for producing polyolefins in a gas phase reactor using condensing agent(s) (CAs), and real-time calculation of the ratio of one type of CA to another CA within a CA composition. This disclosure provides methods for controlling condensed phase cooling in a gas phase reactor used to polymerize olefins. The polymerization may employ one or more polymerization catalysts to polymerize one or more olefin monomers, and may include introducing a first condensing agent and a second condensing agent in a ratio of first condensing agent to second condensing agent, which ratio is calculated by ascertaining a stick limit for a first condensing agent, calculating an equivalence factor relating the first condensing agent and a second condensing agent, ascertaining a total allowable condensing agent, and calculating a first amount of the first condensing agent removed and replaced by a second amount of the second condensing agent.