Abstract: An apparatus and method for removing polymer solids from a slurry loop reactor. A discharge conduit having a longitudinal axis and an end section for removing polymer solids from the slurry loop reactor is provided. The discharge conduit is attached to the slurry loop reactor so that the longitudinal axis and at least a portion of an outer wall of the slurry loop reactor form an angle of less than about 90 degrees. The end section includes a first edge and a second edge that extends past at least a portion of an inner wall of the slurry loop reactor into a liquid reactor slurry. Polymer solids contained within the liquid reactor slurry are concentrated on the second edge so that an average polymer solids concentration in the discharge slurry is greater than an average polymer solids concentration of the liquid reactor slurry within the slurry loop reactor.

Abstract: Multiple components are selected, conveyed, and measured in a polymerization system. A control system adjusts the system variables to the desired values. Portions of the components can be fed to a pre-contactor before introduction into the polymerization reactor. The catalyst component concentrations and residence times are tightly controlled in the pre-contactor to affect product properties. The pre-contactor can be a single or multiple combinations of a CSTR or plug flow pre-contactors.

Abstract: A method for transferring polymer within a polymerization system, comprising continuously withdrawing the polymer from the reactor and conveying the polymer from a reactor to a flash chamber via a pressure differential between the reactor and the flash chamber. A method for transferring polymer within a polymerization system comprising conveying the polymer from a reactor to a flash chamber via a pressure differential between the reactor and the flash chamber and purging interstitial gases from the polymer prior to conveying the polymer from the sash chamber to a purge column. A method for transferring polymer within a polymerization system comprising conveying the polymer from a flash chamber directly to a purge column via a pressure differential between the flash chamber and the purge column.

Abstract: An olefin polymerization process and apparatus wherein a fluid slurry comprising monomer, diluent and catalyst is circulated in a continuous loop reactor by two or more pumps. The process and apparatus allow operating the reaction at significantly higher solids content in the circulating fluid slurry. In a preferred embodiment, the fluid slurry is circulated by two impellers arranged so that the downstream impeller benefits from the rotational energy imparted by the upstream impeller. An olefin polymerization process operating at higher reactor solids by virtue of more aggressive circulation has improved efficiencies, particularly in larger-volume reactors.

Abstract: A manufacturing process for producing polyolefin, having a feed system, a reactor system including at least one polymerization reactor, a diluent/monomer recovery system, a fractionation system, and an extrusion/loadout system having an extruder. The manufacturing process is configured to consume less than 325 kilowatt-hours of electricity per metric ton of polyolefin produced.

Abstract: 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.

Abstract: A method for transferring polymer within a polymerization system, comprising continuously withdrawing the polymer from the reactor and conveying the polymer from a reactor to a flash chamber via a pressure differential between the reactor and the flash chamber. A method for transferring polymer within a polymerization system comprising conveying the polymer from a reactor to a flash chamber via a pressure differential between the reactor and the flash chamber and purging interstitial gases from the polymer prior to conveying the polymer from the flash chamber to a purge column. A method for transferring polymer within a polymerization system comprising conveying the polymer from a flash chamber directly to a purge column via a pressure differential between the flash chamber and the purge column.

Abstract: We disclose a monovinylarene/conjugated diene block copolymer, comprising: (i) a random (conjugated dienex/monovinylareney)m block, wherein x is about 2.5 wt % to about 10 wt %, y is from about 90 wt % to about 97.5 wt %, and x+y is about 97.5 wt % to 100 wt %; and (ii) a (conjugated diene)n block; wherein n is from about 20 wt % to about 30 wt %, m is from about 70 wt % to about 80 wt %, and m+n is from about 90 wt % to 100 wt %. We also disclose a method of forming the block copolymer and a method for fabricating an article from the block copolymer. The block copolymer typically exhibits a Tg at least about 10° C. less than the Tg of a reference polymer differing only in that x is about 0 wt % and y is about 100 wt %.

Abstract: A polymerization process and apparatus in which olefin monomer is polymerized in a liquid diluent in a loop reactor having a relatively smooth inner wall. Another aspect of the invention includes a first polymerization step in which at least one olefin monomer is polymerized in a liquid diluent in a loop reactor to produce a first product fluid slurry comprising liquid diluent and solid olefin polymer particles having a relatively low melt index. A second polymerization step is then provided in which at least one olefin monomer is polymerized in a liquid diluent in the same loop reactor to produce a fluid slurry comprising liquid diluent and solid olefin polymer particles having a relatively high melt index.