Nova Chemicals (international) S.a.

Chevron Phillips Chemical Company LP

Nova Chemicals Inc.

Nova Chemicals S.a.

Benjamin Milton Shaw

Peter Phung Minh Hoang

Cliff Baar

Victoria Ker

Patrick Lam

Xiaoliang Gao

Charles Ashton Garret Carter

Craig Allan Hulet

Ross Donald Moreton

John D Hottovy

Dale A Zellers

Yves Lacombe

Dusan Jeremic

Yan Jiang

Ian Douglas McKay

Lee Douglas Henderson

Alexei Kazakov

Ian Ronald Jobe

Kamal Kamel Botros

James Arthur Auger

Billy Santos

John Iatrou

Dale Warren Nagel

Amy Marie Jones

Kent Gray Jensen

Ian Woods

Joel Racle

Andy Mak

Amanda Dolores Murphy

Teresa Yuk Woon Leung

Mark Jay Ziebart

Kent Jensen

Craig Hulet

Ian Douglas Mckay

Cliff Robert Barr

Peter Phung Hoang

Cliff Robert Baar

Charles Ashton Carter

Billy Gaspar Santos

Provided herein is a unidirectional blow down system for a high-pressure tubular reactor with a hyper that minimizes the tube wall metal temperature during a decomposition event wherein the system prevents the reactor walls from reaching a temperature capable of causing the tube metal to austenize. Also provided are methods of designing and methods of operating a unidirectional blowdown system.

Method for designing multi-valve uni-direction blowdown system for a high pressure tubular reactor

In the high pressure polymerization of ethylene homopolymers or copolymers, conditions in the high pressure recycle system may lead to the build-up of low molecular weight oligomers and waxes. Sequentially draining knock-out pots, located downstream of a high pressure separator, at regular intervals can reduce the build-up of low molecular weight oligomers and waxes during the high pressure polymerization of alpha olefins.

Mitigation of wax levels in the high pressure low density polyethylene process

Olefin polymerization is carried out with a supported phosphinimine catalyst which has been treated with a long chain substituted amine compound.

Modified phosphinimine catalysts for olefin polymerization

Olefin polymerization is carried out with a single site polymerization catalyst in the presence of a continuity additive. The continuity additive is a cocktail containing one or more dialkanolamide derived from a fatty acid, an oil soluble sulfonic acid and a dialkanolamine.

Reactor operability in a gas phase polymerization process

Polyethylene films having a good balance of optical and mechanical properties are disclosed. The films are derived from ethylene copolymer compositions made with a suitably substituted phosphinimine catalyst. The ethylene copolymers have very narrow molecular weight distributions and broadened comonomer distributions.

Polyethylene film

A method for altering the polymer architecture of ethylene copolymers made with a supported phosphinimine polymerization catalyst. The method involves changing the amount of a catalyst modifier added to a reactor separately from or together with a supported phosphinimine polymerization catalyst.

Methods for controlling ethylene copolymer properties

In the high pressure of polymerization of ethylene homopolymer or copolymers conditions in the reactor may become unstable leading to the decomposition ('decomp') of the reaction mixture. Monitoring temperature excursions traveling through the reactor over close thermocouples (a roller) to detect changes in the mean temperature and the moving temperature front for a group of thermocouples detects conditions potentially leading to a decomp.

Roller detection

The time between shut downs of a gas phase reactor for the polymerization of polyethylene may be significantly increased if the catalyst used is not prepared by impregnating the support with a solution of catalyst in an electron donor; the reaction is controlled using the addition of activator based on polymer production rate and the recycle stream contains a condensed liquid phase in an amount greater than 13 weight %. Operating the reactor in this manner increase the time between cleaning the cooler (heat exchanger) the bed plate, or both from about 4 to 6 months to not less than about 24 months.

Increased run length in gas phase reactors

Fouling in a dispersed phase reactor in the presence of a phosphinimine catalyst and MAO may be reduced by reducing the loading of the phosphinimine catalyst to provide from 0.02 to 0.031 mmol of transition M per g of catalyst while still maintaining a productivity of not less than 2500 g of polymer/gram of catalyst. The catalyst may optionally be used in the presence of an antistatic agent.

Reduced reactor fouling

Single site reactor/catalyst continuity in a dispersed phase reaction in terms of initial activation and subsequent deactivation may be improved by treating the support with a metal salt. The activator and catalyst are then deposited on the treated support. The resulting catalyst has a lower consumption of ethylene during initiation and a lower rate of deactivation. Preferably the catalyst is used with an antistatic agent.

Reactor continuity

Techniques are provided for the prevention of reactor fouls in polymerization reactors. A technique is provided for limiting polymer particle size to prevent or limit the occurrence of reactor fouls associated with large polymer particles. A technique is also provided for measuring reactor temperature at one or more local hot spots of the reactor and for controlling the polymerization reaction based upon these temperature measurements. In particular, control of the reaction may be based on the hottest temperature, such that the hottest temperature in the reactor is maintained within the reactor fouling curve. A technique is also discussed for predicting reactor fouls by using statistical analyses, such as periodogram analysis, to identify leading indicators of impending fouls. Preventative measures may be performed upon identification of such a leading indicator. In addition, the statistical analyses may be used to identify catalysts having less propensity to foul.

Method and system to reduce polymerization reactor fouling

A method of starting up a gas phase polymerization reactor, comprising controlling an amount of hydrocarbon absorbed in a polymer seedbed during startup to avoid formation of agglomerates or sheeting on an interior wall of the reactor. A system for of starting up a gas phase polymerization reactor, comprising a controller coupled to the polymerization reactor and controlling an amount of hydrocarbon absorbed in a polymer seedbed during startup to avoid formation of agglomerates or sheeting on an interior wall of the reactor.

Method for polymerizing olefins in a gas phase reactor using a seedbed during start-up

Growing community of inventors

Calgary, Canada

Benjamin Milton Shaw