The present invention relates to a method for consecutively producing at least two different polyethylene resins in one slurry loop reactor, comprising producing a first polyethylene resin in the presence of a Ziegler-Natta and/or a Chromium catalyst, and consecutively producing a second polyethylene resin in the presence of a metallocene catalyst, characterized in that the ratio of the melt flow index of the first produced polyethylene resin to the melt flow index of the second produced polyethylene resin is at least 0.3.

A system and method for discharging a transfer slurry from a first polymerization reactor through a transfer line to a second polymerization reactor, the transfer slurry including at least diluent and a first polyethylene. A product slurry is discharged from the second polymerization reactor, the product slurry including at least diluent, the first polyethylene, and a second polyethylene. The velocity, pressure drop, or pressure loss due to friction in the transfer line is determined, and a process variable adjusted in response to the velocity, pressure drop, or pressure loss not satisfying a specified value.

A system and method for discharging a transfer slurry from a first polymerization reactor through a transfer line to a second polymerization reactor, the transfer slurry including at least diluent and a first polyethylene. A product slurry is discharged from the second polymerization reactor, the product slurry including at least diluent, the first polyethylene, and a second polyethylene. The velocity, pressure drop, or pressure loss due to friction in the transfer line is determined, and a process variable adjusted in response to the velocity, pressure drop, or pressure loss not satisfying a specified value.

A method of monitoring a solid component of a reactor feed stream in a polymer production system, comprising (a) measuring a turbidity of the reactor feed stream, wherein the reactor feed stream comprises a solid component of a polymerization catalyst system, and (b) translating the turbidity of the reactor feed stream into a concentration of the solid component in the reactor feed stream. A method of monitoring a solid component of a reactor feed stream in a polymer production system, comprising (a) measuring a turbidity of a precontactor feed stream, wherein the precontactor feed stream comprises a solid component of a polymerization catalyst system, and (b) translating the turbidity of the precontactor feed stream into a concentration of the solid component in a precontactor effluent stream, wherein the precontactor effluent stream comprises the reactor feed stream.

A polyolefin production system including: a first reactor configured to produce a first discharge slurry having a first polyolefin; a second reactor configured to produce a second discharge slurry having a second polyolefin; and a post-reactor treatment zone having at least a separation vessel configured to receive the second discharge slurry or both the first discharge slurry and the second discharge slurry.

A reactor for the polymerization of olefins comprising a first inlet for introducing a first stream comprising monomer(s), catalyst(s) and optionally hydrogen, solvent or comonomer(s) and/or mixtures thereof, at least one outlet for withdrawing a product stream, characterized in that the reactor further comprises at least one second inlet for introducing a second stream comprising monomer(s), catalyst(s) and optionally hydrogen, solvent or comonomer(s) and/or mixtures thereof; and a process for polymerizing olefins in a reactor according to the present invention, comprising the steps of introducing monomer(s), catalyst(s), and optionally hydrogen, solvent or comonomer(s) and/or mixtures thereof as the first stream via the first inlet into the reactor forming a reaction mixture; polymerizing a polymer from the reaction mixture; withdrawing the product stream via the at least one outlet from the reactor; characterized in that the process comprises a further step of introducing a second stream comprising monomer(s), catalyst(s), and optionally hydrogen, solvent or comonomer(s) and/or mixtures thereof into the reactor via the at least one second inlet into the reactor.

There is a need to provide a system that can meet the thermal requirements of high-temperature reactions, particularly those involving molten substances. There is provided a new fluid reactor, and a method for using the reactor. The reactor for reacting a fluid with a gas comprises two first vessels in direct contact with two second vessels, with apertures arranged in a series to direct fluid in the first vessels to flow towards and through the aperture of each first vessel and into a connected second vessel by gas entering each first vessel through a gas inlet, and with apertures of the second vessels that allow the fluid flowing from each first vessel through each second vessel to flow into a first vessel connected to the second vessel.