Exxonmobil Chemical Patents Inc.

Exxon Chemical Patents, Inc.

Chevron Phillips Chemical Company LP

Thomas W Towles

Scott Thomas Roger

James Austin Kendrick

Anthony Nicholas Speca

Stanley J Katzen

Robert G Depierri

Edward F Smith

James E Skinner

Scott T Roger

James A Kendrick

Provided herein is a method for operating a slurry polymerization reaction system to reduce, inhibit, and/or prevent fouling in the polymer recovery and separation apparatus, including one or more portions of a high pressure flash tank. The method generally comprises polymerizing a monomer feed in a slurry polymerization reactor in the presence of catalyst and diluent to produce a polymerization effluent; continuously discharging at least a portion of said polymerization effluent from the reactor through a discharge valve; combining a catalyst poison stream with the polymerization effluent downstream of said discharge valve, wherein the catalyst poison stream comprises a catalyst poison that is a gas at standard conditions; and flashing the combination of polymerization effluent and catalyst poison stream in a first flash tank.

Method and apparatus for reducing fouling

The present invention relates to the removal of hydrocarbon residues from a catalyst and more specifically the air activation of a catalyst containing hydrocarbon residues. It also relates to extruded pipe and utility conduit resins comprising polyethylene, household/industrial chemicals container resins, and to a polyethylene resin particularly suitable for large parts by blow molding and sheet extrusion procedures, wherein the resin is made by a process using an activated chromium and titanium-based catalyst.

Catalyst activation and resins therefrom

A process/apparatus is disclosed for continuously separating a liquid medium comprising diluent and unreacted monomers from a polymerization effluent comprising diluent, unreacted monomers and polymer solids, comprising a continuous discharge of the polymerization effluent from a slurry reactor through a discharge valve and transfer conduit into a first intermediate pressure flash tank with a conical bottom defined by substantially straight sides inclined at an angle to that of horizontal equal to or greater than the angle of slide of the slurry/polymer solids and an exit seal chamber of such diameter (d) and length (l) as to maintain a desired volume of concentrated polymer solids/slurry in the exit seal chamber such as to form a pressure seal while continuously discharging a plug flow of concentrated polymer solids/slurry bottom product of the first flash tank from the exit seal chamber through a seal chamber exit reducer with inclined sides defined by substantially straight sides inclined at an angle to that of horizontal equal to or greater than the angle of slide of the polymer solids which remain after removal of about 50 to 100% of the inert diluent therefrom to a second flash tank at a lower pressure.

Continuous slurry polymerization apparatus

The present invention relates to methods for controlling fouling in the reaction zone of slurry-type olefin polymerization reactors by measuring a process operating parameter and by responding to said process operating parameter, e.g., by introducing a gaseous poison for the polymerization catalyst in response to a comparison between said measured parameter and a fouling parameter limit for said measured parameter.

Method for controlling fouling in slurry-type polymerization reactors

A method for polymerizing ethylene is provided. The method can include preparing a supported catalyst composition comprising the steps of: (a) dehydrating a chromium impregnated support; (b) at least partially dissolving a titanium-containing compound in one or more inert solvents to provide a solution comprising the titanium-containing compound; (c) contacting the dehydrated chromium impregnated support with the titanium-containing solution to provide a mixture comprising the solvent, titanium-containing compound and chromium impregnated support; (d) removing the solvent from the mixture; and (e) activating the product of step (d) at a temperature of at least 800&#xb0; F. (427&#xb0; C.) to provide a supported titanated chrome catalyst composition. The supported titanated chrome catalyst composition can be feed to a slurry reactor, and contacted with an optional co-catalyst, under polymerization conditions, with ethylene.

Method for catalyst preparation and improved polyethylene blow molding resin

A process of converting a loop reactor into multiple loop reactors comprising starting with a loop reactor comprising at least 8 vertical legs, at least two non-vertical conversion runs, each non-vertical run connected in fluid flow communication with two vertical legs; at least two feed inlets; and at least two continuous discharge conduits; disconnecting at least one connection of each conversion run; and reconnecting each conversion run in fluid flow communication with a different vertical leg in such a manner to form multiple loop reactors each having at least one feed inlet and at least one continuous discharge conduit.

Continuous slurry polymerization process and apparatus

A process/apparatus is disclosed for continuously separating a liquid medium comprising diluent and unreacted monomers from a polymerization effluent of a slurry loop reactor containing a flow of slurry therein, comprising a discharge conduit extending a distance into the loop reactor; the conduit having a longitudinal axis and an opening inside the loop reactor; at least a portion of the conduit being curved along its longitudinal axis inside the loop reactor; and the opening substantially facing the flow of the slurry, wherein the discharge conduit is located within a lower leg of the loop reactor such that a continuous discharge of the polymerization effluent from a slurry reactor through a discharge valve and transfer conduit into a first intermediate pressure flash tank wherein volatile inert diluent and unreacted monomers are removed and the polymer solids which remain after removal of about 50 to 100% of the inert diluent therefrom to a second flash tank at a lower pressure.

Continuous slurry polymerization volatile removal

A process/apparatus is disclosed for continuously separating a liquid medium comprising diluent and unreacted monomers from a polymerization effluent comprising diluent, unreacted monomers and polymer solids, comprising a continuous discharge of the polymerization effluent from a slurry reactor through a discharge valve and transfer conduit into a first intermediate pressure flash tank with a conical bottom defined by substantially straight sides inclined at an angle to that of horizontal equal to or greater than the angle of slide of the slurry/polymer solids and an exit seal chamber of such diameter (d) and length (l) as to maintain a desired volume of concentrated polymer solids/slurry in the exit seal chamber such as to form a pressure seal while continuously discharging a plug flow of concentrated polymer solids/slurry bottom product of said first flash tank from the exit seal chamber through a seal chamber exit reducer with inclined sides defined by substantially straight sides inclined at an angle to that of horizontal equal to or greater than the angle of slide of the polymer solids which remain after removal of about 50 to 100% of the inert diluent therefrom to a second flash tank at a lower pressure.

Growing community of inventors

Baton Rouge, LA, United States of America

Thomas W Towles