Abstract: A method for the control of a polymerization process, which method employs the combination of a densitometer measurement of the polymerization reaction mixture and a quadratic computer model.

Abstract: A method for solution polymerizing ethylene wherein an ethane purge stream is separated, subjected to high efficiency cryogenic distillation, and a side cut from that distillation recycled to the polymerization process while the overhead and bottoms from that distillation are removed from the polymerization process.

Abstract: A method and apparatus for operating a pressure vessel containing a bed of particulate material comprising substantially leveling the bed and employing a plug-flow inducer in the bed.

Abstract: A method and apparatus for operating a pressure vessel containing a bed of particulate material comprising substantially leveling the bed and employing a fluid flow distributor above the bed.

Abstract: A method for the control of a polymerization process, which method employs the combination of a densitometer measurement of the polymerization reaction mixture and a quadratic computer model.

Abstract: A method and apparatus for operating a pressure vessel containing a bed of particulate material comprising substantially leveling the bed and employing a plug-flow inducer in the bed.

Abstract: A method and apparatus for operating a pressure vessel containing a bed of particulate material comprising substantially leveling the bed and employing a fluid flow distributor above the bed.

Abstract: An advanced control method is disclosed for the polymerization of an alpha-olefin in a substantially horizontal, quench-cooled, stirred bed reactor.

Abstract: The molecular weights (Mw and Mn) and polydispersity (Mw/Mn) of a polymer have significant impact on the final product properties and processability of materials made out of it. This invention provides a method for on-line prediction of polymer properties. In a continuous polymerization reactor in which an irreversible polymerization reaction occurs, sensors provide axial temperature and pressure profile in the reactor as well as monomer flow rates and concentration for determining Mw, Mn and polydispersity. Based on a non-Newtonian fluid mechanics analysis, differential influx analysis of a side stream incorporation and determination of the moments of the molecular weight distribution via a Newton-Raphson algorithm, the model calculates an axial polymer properties profile.On-line real time "analytical measurement" of polymer properties is used to alert the operator of unusual reactor problems, to optimize reactor operation during shut-down and start-up or rate changes.