Patent application number | Description | Published |
20100282075 | Systems and Methods for Removing Entrained Particulates from Gas Streams, and Reactor Systems - Various methods and systems for removing particulates from a cycle gas stream, e.g., in a reactor system, are provided. In certain embodiments, the methods are performed in conjunction with a polymerization reactor system such as a gas-phase reactor system for production of polyolefin polymers. The methods comprise the step of compressing a gas stream having particulates entrained therein. | 11-11-2010 |
20110196112 | Methods for Cleaning the Distributor Plate in a Fluidized Bed Reactor System - A method for cleaning a distributor plate in a fluidized bed polymerization reactor system according to one embodiment includes, in a first mode, operating with about a normal, baseline value of superficial gas velocity in a fluidized bed polymerization reactor system having a reactor vessel, a recycle line, and a distributor plate in the reactor vessel near an inlet of the reactor vessel. In a second mode, the superficial gas velocity is increased above the baseline value of the first mode to a level sufficient to raise the temperature of the cycle gas at the inlet above an average temperature of the cycle gas at the inlet in the first mode, and to a level sufficient to dislodge foulant from holes in the distributor plate. | 08-11-2011 |
20110294973 | Method for Seed Bed Treatment for a Polymerization Reaction - A method for preparing a reactor for performance of a polymerization reaction, the method including providing at least one seed bed into the reactor; wherein the at least one seed bed includes at least one organometallic compound and polymer particles. | 12-01-2011 |
20120041159 | Systems and Methods for Monitoring a Polymerization Reaction - Systems and methods for monitoring a polymerization reactor are provided. The method can include estimating an acoustic condition of a polymer produced in a reactor. The method can also include estimating a stickiness control parameter of the polymer produced in the reactor. The method can further include pairing the acoustic condition with the stickiness control parameter to provide a paired acoustic condition and stickiness control parameter. | 02-16-2012 |
20120070575 | METHODS FOR APPLYING SOLUTION CATALYSTS TO REACTOR SURFACES - A method for treating at least one interior surface (for example, a bed wall) of a fluidized bed polymerization reactor system, including by applying a solution catalyst (preferably at least substantially uniformly and in liquid form) to each surface, and optionally (where a catalyst component of the solution catalyst comprises at least one chromium containing compound) oxidizing at least some of the applied chromium containing compound in a controlled manner. | 03-22-2012 |
20120329962 | Methods for Operating a Polymerization Reactor - Methods for shutting down and restarting polymerization in a gas phase polymerization reactor are provided. The method can include introducing a polymerization neutralizer to the reactor in an amount sufficient to stop polymerization therein. The method can also include stopping recovery of a polymer product from the reactor and stopping introduction of a catalyst feed and a reactor feed to the reactor. The method can also include adjusting a pressure within the reactor from an operating pressure to an idling pressure. The method can also include adjusting a superficial velocity of a cycle fluid through the reactor from an operating superficial velocity to an idling superficial velocity. The method can also include maintaining the reactor in an idled state for a period of time. | 12-27-2012 |
20130085245 | Methods for Reducing Static Charge of a Catalyst and Methods for Using the Catalyst to Produce Polyolefins - Catalysts and methods for making and using the same are provided. The method for fabricating a catalyst may includes contacting a supported catalyst with a monomer under conditions that reduce an overall charge of the catalyst to less than about 75% of an initial charge of the catalyst. A method for polymerization may include introducing a pre-polymerized catalyst and one or more olefins into a gas phase fluidized bed reactor, operating the reactor at conditions sufficient to produce a polyolefin, wherein the polymerization is carried out in the substantial absence of any continuity additives. | 04-04-2013 |
20140200317 | Methods for Reducing Static Charge of a Catalyst and Methods for Using the Catalyst to Produce Polyolefins - Catalysts and methods for making and using the same are provided. The method for fabricating a catalyst may includes contacting a supported catalyst with a monomer under conditions that reduce an overall charge of the catalyst to less than about 75% of an initial charge of the catalyst. A method for polymerization may include introducing a pre-polymerized catalyst and one or more olefins into a gas phase fluidized bed reactor, operating the reactor at conditions sufficient to produce a polyolefin, wherein the polymerization is carried out in the substantial absence of any continuity additives. | 07-17-2014 |
Patent application number | Description | Published |
20080312375 | Polymerization Process - This invention is directed to processes of making polymer in the presence of a fluorinated hydrocarbon and recovering the polymer. The processes provided enable polymerization processes to be practiced with minimal fouling in the reaction system, and allows for the recovery of the fluorinated hydrocarbon and other hydrocarbons such as hydrocarbons for re-use in the process or hydrocarbon by-products from the polymerization process. The invention is particularly beneficial in the production of propylene polymers and copolymes using bulky ligand metallocene-type catalyst systems. | 12-18-2008 |
20080319583 | Method for on-line monitoring and control of polymerization processes and reactors to prevent discontinuity events - Generally, a method of monitoring a polymerization reaction in a fluid bed reactor to generate, in on-line fashion, data indicative of the imminent occurrence of a discontinuity event (for example, sheeting) and optionally also control the reaction to prevent the occurrence of the discontinuity event is provided. Typical embodiments include the steps of generating in on-line fashion at least one of bed static data indicative of static charge in the fluidized bed and carryover static data indicative of carryover static; and generating at least one of temperature data (in on-line fashion using at least one monitored reaction parameter) indicative of a first temperature and acoustic emission data indicative of resin stickiness in the reactor, where the first temperature is indicative of at least one of degree of resin stickiness in the reactor and a characteristic of melting behavior of polymer resin in the reactor in the presence of at least one diluent. | 12-25-2008 |
20090018279 | Method for controlling sheeting in gas phase reactors - Embodiments of the present invention relate to measuring and controlling static in a gas phase reactor polymerization. In particular, embodiments relate to monitoring carryover static in an entrainment zone during gas phase polymerization to determine the onset of reactor discontinuity events such as chunking and sheeting. Embodiments also relate to monitoring carryover static to determine the need for effective additions of continuity additives that minimize reactor static activity and thereby preventing discontinuity events. | 01-15-2009 |
20090137756 | Bulk density promoting agents in a gas-phase polymerization process to achieve a bulk particle density - Disclosed herein is a gas phase polymerization process including the steps of passing a recycle stream through a fluidized bed in a gas phase fluidized bed reactor in the presence of a bulk density promoting agent, wherein the bulk density promoting agent is of a saturated hydrocarbon and/or a non-polymerizable unsaturated hydrocarbon having 6 or more carbon atoms; polymerizing at least one alpha-olefin monomer in the presence of a catalyst to produce an alpha-olefin polymer; and controlling an amount of the bulk density promoting agent in the reactor such that a bulk density of the alpha-olefin polymer discharged from the reactor is greater than or equal to about 480 kg/m | 05-28-2009 |
20100144983 | Methods for determining temperature value indicative of resin stickiness from data generated by polymerization reaction monitoring - In some embodiments, a method including the steps of monitoring a polymerization reaction which produces a polymer resin in a fluid bed reactor, where a dry melt reference temperature is characteristic of melting behavior of a dry version of the resin, and in response to data indicative of at least one monitored parameter of the reaction, determining in on-line fashion a reduced melt reference temperature that is at least substantially equal to the difference between the dry melt reference temperature and a temperature by which the dry melt reference temperature is depressed by the presence of condensable diluent gas with the resin in the reactor. Optionally, the method also includes the step of controlling the reaction in response to the reduced melt reference temperature or a stickiness parameter determined from the reduced melt reference temperature. | 06-10-2010 |
20100184927 | METHODS FOR APPLYING SOLUTION CATALYSTS TO REACTOR SURFACES - A method for treating at least one interior surface (for example, a bed wall) of a fluidized bed polymerization reactor system, including by applying a solution catalyst (preferably at least substantially uniformly and in liquid form) to each surface, and optionally (where a catalyst component of the solution catalyst comprises at least one chromium containing compound) oxidizing at least some of the applied chromium containing compound in a controlled manner. | 07-22-2010 |
20100286346 | Method for On-Line Determination of Degree or Onset of Resin Stickiness Using Acoustic Data - Provided is a method for monitoring a polymerization reaction in a fluid bed reactor to determine in on-line fashion a current value, and preferably also a limiting value, of a stickiness control temperature, and optionally controlling the reaction in response thereto in an effort to prevent occurrence of a discontinuity event. The stickiness control temperature is a temperature indicative of a characteristic of melting behavior of polymer resin in the reactor, and may be indicative of occurrence of resin sheeting or another discontinuity event. Optionally, a predetermined relation between values of acoustic energy in the reactor and values of a stickiness control temperature is used to provide error checking for determination of the stickiness control temperature, or a current value of the stickiness control temperature is determined from acoustic data and a predetermined relation between values of an acoustic condition in the reactor and values of the stickiness control temperature. | 11-11-2010 |