A process for screening polymer from a polymer-lean vapor stream, whereby the process comprises the steps of separating an effluent stream comprising the polymer and a first mixture of hydrocarbons into a polymer-rich stream and the polymer-lean vapor stream; spraying a condensed vapor composition comprising a second mixture of hydrocarbons into the polymer-lean vapor stream via a condensed vapor composition stream; screening a screened condensed vapor composition stream comprising the polymer and the condensed vapor composition from the polymer-lean vapor stream.

A process for screening polymer from a polymer-lean vapor stream, whereby the process comprises the steps of separating an effluent stream comprising the polymer and a first mixture of hydrocarbons into a polymer-rich stream and the polymer-lean vapor stream; spraying a condensed vapor composition comprising a second mixture of hydrocarbons into the polymer-lean vapor stream via a condensed vapor composition stream; screening a screened condensed vapor composition stream comprising the polymer and the condensed vapor composition from the polymer-lean vapor stream.

The present invention relates to a method for producing an ethylene-based copolymer, and more particularly, to a method for producing an ethylene-based copolymer capable of increasing process efficiency by preventing plugging and corrosion of a facility. The method for producing an ethylene-based copolymer includes a producing mode and a washing mode of which one is selectively performed. The producing mode includes: a) hyper-compressing primary compressed ethylene, and a mixture including a carboxylic acid-containing comonomer and a polar solvent to produce a compressed material; b) reacting the compressed material to produce a reaction product including an ethylene-based copolymer; and c) separating and recovering unreacted residues from the reaction product and introducing the unreacted residues into the mixture of step a). The washing mode includes: re-supplying the compressed material produced in step a) to step a) as a mixture, without performing step b).

The present invention relates to a method for producing an ethylene-based copolymer, and more particularly, to a method for producing an ethylene-based copolymer capable of increasing process efficiency by preventing plugging and corrosion of a facility. The method for producing an ethylene-based copolymer includes a producing mode and a washing mode of which one is selectively performed. The producing mode includes: a) hyper-compressing primary compressed ethylene, and a mixture including a carboxylic acid-containing comonomer and a polar solvent to produce a compressed material; b) reacting the compressed material to produce a reaction product including an ethylene-based copolymer; and c) separating and recovering unreacted residues from the reaction product and introducing the unreacted residues into the mixture of step a). The washing mode includes: re-supplying the compressed material produced in step a) to step a) as a mixture, without performing step b).

A method of preparing an aromatic vinyl compound-vinyl cyanide compound polymer includes polymerizing a reaction mixture containing an aromatic vinyl compound, a vinyl cyanide compound, and an organic solvent in a reactor and transferring the vaporized reaction mixture present in the upper space of the reactor to a heat exchanger via a pipe and condensing the vaporized reaction mixture. The condensed reaction mixture is transferred to one side of the pipe and sprayed into the pipe, the flow velocity of the reaction mixture vaporized in the reactor is reduced, and temperature is lowered. Accordingly, a phenomenon wherein polymer particles in a reactor are sucked into a heat exchanger is prevented, and occurrence of polymerization in the heat exchanger is suppressed. Therefore, productivity and quality may be improved.

A method of preparing an aromatic vinyl compound-vinyl cyanide compound polymer includes polymerizing a reaction mixture containing an aromatic vinyl compound, a vinyl cyanide compound, and an organic solvent in a reactor and transferring the vaporized reaction mixture present in the upper space of the reactor to a heat exchanger via a pipe and condensing the vaporized reaction mixture. The condensed reaction mixture is transferred to one side of the pipe and sprayed into the pipe, the flow velocity of the reaction mixture vaporized in the reactor is reduced, and temperature is lowered. Accordingly, a phenomenon wherein polymer particles in a reactor are sucked into a heat exchanger is prevented, and occurrence of polymerization in the heat exchanger is suppressed. Therefore, productivity and quality may be improved.

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.

Systems and methods of reducing heat exchanger fouling rate and of producing polyolefins are provide herein. In some aspects, the methods include providing a first gas stream comprising a gas and entrained fine polyolefin particles to a gas outlet line; preferentially removing a portion of the entrained fine polyolefin particles from the gas outlet line to form a bypass stream comprising a higher concentration of the entrained fine polyolefin particles than is present in the first gas stream; providing the bypass stream to a bypass line comprising a bypass line inlet and a bypass line outlet, wherein the bypass line inlet is located upstream of a first heat exchanger, and wherein the bypass line outlet is located downstream of the first heat exchanger; providing at least a portion of the first gas stream to the first heat exchanger, which produces a first cooled gas stream; 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, wherein a temperature of the combined gas stream is below the dew point of the combined gas stream.

Systems and methods of reducing heat exchanger fouling rate and of producing polyolefins are provide herein. In some aspects, the methods include providing a first gas stream comprising a gas and entrained fine polyolefin particles to a gas outlet line; preferentially removing a portion of the entrained fine polyolefin particles from the gas outlet line to form a bypass stream comprising a higher concentration of the entrained fine polyolefin particles than is present in the first gas stream; providing the bypass stream to a bypass line comprising a bypass line inlet and a bypass line outlet, wherein the bypass line inlet is located upstream of a first heat exchanger, and wherein the bypass line outlet is located downstream of the first heat exchanger; providing at least a portion of the first gas stream to the first heat exchanger, which produces a first cooled gas stream; 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, wherein a temperature of the combined gas stream is below the dew point of the combined gas stream.

A method of preparing an aromatic vinyl compound-vinyl cyanide compound polymer includes polymerizing a reaction mixture containing an aromatic vinyl compound, a vinyl cyanide compound, and an organic solvent in a reactor and transferring the vaporized reaction mixture present in the upper space of the reactor to a heat exchanger via a pipe and condensing the vaporized reaction mixture. The condensed reaction mixture is transferred to one side of the pipe and sprayed into the pipe, the flow velocity of the reaction mixture vaporized in the reactor is reduced, and temperature is lowered. Accordingly, a phenomenon wherein polymer particles in a reactor are sucked into a heat exchanger is prevented, and occurrence of polymerization in the heat exchanger is suppressed. Therefore, productivity and quality may be improved.