A method of manufacturing bulked continuous carpet filament which, in various embodiments, comprises: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) passing the group of flakes through an MRS extruder while maintaining the pressure within the MRS portion of the MRS extruder below about 1.5 millibars; (E) passing the resulting polymer melt through at least one filter having a micron rating of less than about 50 microns; and (F) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.

In particular embodiments, a process for producing bulked continuous carpet filament from recycled polymer utilizes two vacuum pumps (140A, 140B) in combination with a single extruder (100). In various embodiments, the dual vacuum arrangement (e.g., at least two vacuum pumps (140A, 140B)) operably coupled to the single extruder (e.g., MRS extruder (100)) may be configured to remove one or more impurities from recycled polymer as the recycled polymer passes through the extruder.

Systems for manufacturing bulked continuous carpet filament from polymer, where the systems are configured for: (1) melting polymer (e.g., derived from post-consumer PET bottles) to create a first single stream of polymer melt; (2) separating the first single stream of polymer melt into multiple streams of polymer melt; (3) exposing the multiple streams of polymer melt to a pressure of between about 0 millibars and about 5 millibars; (4) allowing the multiple streams of polymer melt to fall into a receiving section of a melt processing unit; (5) recombining the multiple streams of polymer melt into a second single stream of polymer melt; and (6) providing the second single stream of polymer melt to one or more spinning machines that are configured to form the second single stream of polymer melt into bulked continuous carpet filament.

A screw includes a screw main body, a conveyance portion conveying a raw material, and a passage provided in the screw main body. The passage includes a first passage element, a second passage element, and a third passage element. The screw main body has a plurality of cylindrical bodies arranged in an axial direction of the rotating shaft. At least a portion of the conveyance portion is formed on outer peripheral surfaces of the cylindrical bodies adjacent to each other, and the passage is formed in the cylindrical body so as to cross over between the adjacent cylindrical bodies.

An extruder screw for a multi-screw extruder for plastics extrusion includes: a feeding and metering zone for melting and homogenizing the plastic and an evacuating zone for carrying away gaseous constituents and a compressing and/or discharging zone; a multi-screw section, which has a plurality of planetary screws, which lie open on the outer circumference of the extruder screw, at least over part of their length; and a driving zone, in which the planetary screws engage by way of a toothing in an external toothing on a central shaft or in an internal toothing in a stator ring or in the inner wall of an extruder bore of the multi-screw extruder. The feeding and metering zone extends into the multi-screw section, wherein the respective part of the planetary screws that is lying in the metering zone is at least partially enclosed.

Systems for manufacturing bulked continuous carpet filament from polymer, where the systems are configured for: (1) melting polymer (e.g., derived from post-consumer PET bottles) to create a first single stream of polymer melt; (2) separating the first single stream of polymer melt into multiple streams of polymer melt; (3) exposing the multiple streams of polymer melt to a pressure of between about 0 millibars and about 5 millibars; (4) allowing the multiple streams of polymer melt to fall into a receiving section of a melt processing unit; (5) recombining the multiple streams of polymer melt into a second single stream of polymer melt; and (6) providing the second single stream of polymer melt to one or more spinning machines that are configured to form the second single stream of polymer melt into bulked continuous carpet filament.

A method of manufacturing bulked continuous carpet filament that includes providing a polymer melt and separating the polymer melt from the extruder into at least eight streams. The multiple streams are exposed to a chamber pressure within a chamber that is below approximately 25 millibars, or another predetermined pressure. The streams are recombined into a single polymer stream. Polymer from the polymer stream is then formed into bulked continuous carpet filament.

A screw includes a screw main body, a conveyance portion conveying a raw material, and a passage provided in the screw main body. The passage includes a first passage element, a second passage element, and a third passage element. The screw main body has a plurality of cylindrical bodies arranged in an axial direction of the rotating shaft. At least a portion of the conveyance portion is formed on outer peripheral surfaces of the cylindrical bodies adjacent to each other, and the passage is formed in the cylindrical body so as to cross over between the adjacent cylindrical bodies.

A system comprising: (1) a grinding unit configured to receive and grind recycled PET bottles into a group of polymer flakes comprising up to about ten percent colored polymer flakes and balance substantially clear polymer flakes; (2) a washing unit configured to wash the group of polymer flakes; and (3) an extruder configured to extrude material in a plurality of different extrusion streams. The extruder may be further configured to: (1) receive a concentrate-polymer mixture comprising a mixture of the polymer flakes and a color concentrate; (2) melt the concentrate-polymer mixture to produce a polymer melt; (3) reduce a pressure within the extruder; and (4) pass the polymer melt through the extruder so that the polymer melt is divided into the plurality of extrusion streams. The system may then filter the polymer melt through at least one filter and form the polymer melt into bulked continuous carpet filament.

A method of manufacturing bulked continuous carpet filament that includes providing a polymer melt and separating the polymer melt from the extruder into at least eight streams. The multiple streams are exposed to a chamber pressure within a chamber that is below approximately 25 millibars, or another predetermined pressure. The streams are recombined into a single polymer stream. Polymer from the polymer stream is then formed into bulked continuous carpet filament.