Methods of reducing heat exchanger fouling rate or of producing polyolefins may include providing a first gas stream comprising a gas and entrained fine polyolefin particles to a gas outlet line; removing a portion of the entrained fine polyolefin particles from the gas outlet line to form a bypass stream; and providing the bypass stream to a bypass line comprising a bypass line inlet and a bypass line outlet. The bypass line inlet and outlet are located upstream and downstream of a first heat exchanger. The methods may further include providing at least a portion of the first gas stream to the first heat exchanger; and combining the bypass stream and a second gas stream at the bypass line outlet to form a combined gas stream comprising one or more olefins or paraffins. A temperature of the combined gas stream is below the dew point of the combined gas stream.

Methods of reducing heat exchanger fouling rate or of producing polyolefins may include providing a first gas stream comprising a gas and entrained fine polyolefin particles to a gas outlet line; removing a portion of the entrained fine polyolefin particles from the gas outlet line to form a bypass stream; and providing the bypass stream to a bypass line comprising a bypass line inlet and a bypass line outlet. The bypass line inlet and outlet are located upstream and downstream of a first heat exchanger. The methods may further include providing at least a portion of the first gas stream to the first heat exchanger; and combining the bypass stream and a second gas stream at the bypass line outlet to form a combined gas stream comprising one or more olefins or paraffins. A temperature of the combined gas stream is below the dew point of the combined gas stream.

A process (and a related system) for collecting samples of a polymerization catalyst or of a catalyst-containing polymer from an operation unit, having an upper end and a lower end, of a polymerization plant, including the steps of: a) extracting a prefixed amount of product from the lower end of the operation unit through a discharge valve; b) directing the product towards a filtering unit through an inlet valve; c) flushing an inert gas through the filtering unit; d) outgassing the filtering unit, through the outlet valve; and e) displacing the filtering unit, for collecting the sample.

A process (and a related system) for collecting samples of a polymerization catalyst or of a catalyst-containing polymer from an operation unit, having an upper end and a lower end, of a polymerization plant, including the steps of: a) extracting a prefixed amount of product from the lower end of the operation unit through a discharge valve; b) directing the product towards a filtering unit through an inlet valve; c) flushing an inert gas through the filtering unit; d) outgassing the filtering unit, through the outlet valve; and e) displacing the filtering unit, for collecting the sample.

A process (and a related system) for collecting samples of a polymerization catalyst or of a catalyst-containing polymer from an operation unit, having an upper end and a lower end, of a polymerization plant, including the steps of: a) extracting a prefixed amount of product from the lower end of the operation unit through a discharge valve; b) directing the product towards a filtering unit through an inlet valve; c) flushing an inert gas through the filtering unit; d) outgassing the filtering unit, through the outlet valve; and e) displacing the filtering unit, for collecting the sample.

A method for producing a polyolefin with a wide molecular weight distribution can comprise: polymerizing one or more monomers in the presence of a catalyst system in a loop reactor to produce a polyolefin product having a polydispersity index of 2.5 to 8, wherein the loop reactor comprises two or more reactors in series, and wherein the loop reactor has a loop thermal gradient of 50° C. to 150° C. and/or a standard deviation of inter-component thermal gradients along the loop reactor of 10° C. to 50° C.

A method for producing a polyolefin with a wide molecular weight distribution can comprise: polymerizing one or more monomers in the presence of a catalyst system in a loop reactor to produce a polyolefin product having a polydispersity index of 2.5 to 8, wherein the loop reactor comprises two or more reactors in series, and wherein the loop reactor has a loop thermal gradient of 50° C. to 150° C. and/or a standard deviation of inter-component thermal gradients along the loop reactor of 10° C. to 50° C.

A slurry polymerization process for the preparation of polyethylene in a reactor cascade of two or more polymerization reactors wherein monomers are polymerized in the polymerization reactors which include a reactor outlet arranged in each reactor bottom for feeding a reactor slurry to a subsequent polymerization reactor and for emptying the polymerization reactor.

A slurry polymerization process for the preparation of polyethylene in a reactor cascade of two or more polymerization reactors wherein monomers are polymerized in the polymerization reactors which include a reactor outlet arranged in each reactor bottom for feeding a reactor slurry to a subsequent polymerization reactor and for emptying the polymerization reactor.

Activators may comprise compounds represented by the Formula [Ar(EHR.sup.1R.sup.2)(OR.sup.3)]d+[M.sup.k+Q.sub.n].sup.d, wherein: Ar is an aryl group; E is nitrogen or phosphorous; R.sup.1 is a C.sub.1-C.sub.30, optionally substituted, linear alkyl group; R.sup.2 is a C.sub.1-C.sub.30, optionally substituted, linear alkyl group; R.sup.3 is a C.sub.10-C.sub.30, optionally substituted, linear alkyl group; M is an element selected from group 13 of the Periodic Table of the Elements; d is 1, 2 or 3; k is 1, 2, or 3; n is 1, 2, 3, 4, 5, or 6; n−k=d; and each Q is independently hydride, bridged or unbridged dialkylamido, halide, alkoxide, aryloxide, hydrocarbyl, substituted hydrocarbyl, halocarbyl, substituted halocarbyl, or halosubstituted-hydrocarbyl radical. Catalysts systems may comprise these activators and methods of preparing polyolefins may use these catalysts systems.