A method of manufacturing bulked continuous carpet filament, said method comprising: providing a PET crystallizer; passing a plurality of flakes of recycled PET through said PET crystallizer to at least partially dry the surface of the PET flakes; after passing said plurality of flakes through said PET crystallizer, at least partially melting said plurality of flakes into a polymer melt; providing a multi-screw extruder that comprises: (i) a first satellite screw extruder, said first satellite screw extruder comprising a first satellite screw that is mounted to rotate about a central axis of said first satellite screw; (ii) a second satellite screw extruder, said second satellite screw extruder comprising a second satellite screw that is mounted to rotate about a central axis of said second satellite screw; and (iii) a pressure regulation system that is adapted to maintain a pressure within said first and second satellite screw extruders below about 18 millibars; using said pressure regulation system to reduce a pressure within said first and second satellite screw extruders to below about 18 millibars; after said step of passing said plurality of flakes through said PET crystallizer, while maintaining said pressure within said first and second satellite screw extruders below about 18 millibars, passing said polymer melt through said multi-screw extruder so that: a first portion of said polymer melt passes through said first satellite screw extruder, and a second portion of said polymer melt passes through said second satellite screw extruder; and after said step of passing said polymer melt through said multi-screw extruder, forming said polymer melt into bulked continuous carpet filament. providing a PET crystallizer; passing a plurality of flakes of recycled PET through said PET crystallizer to at least partially dry the surface of the PET flakes; after passing said plurality of flakes through said PET crystallizer, at least partially melting said plurality of flakes into a polymer melt; providing a multi-screw extruder that comprises: (i) a first satellite screw extruder, said first satellite screw extruder comprising a first satellite screw that is mounted to rotate about a central axis of said first satellite screw; (ii) a second satellite screw extruder, said second satellite screw extruder comprising a second satellite screw that is mounted to rotate about a central axis of said second satellite screw; and (iii) a pressure regulation system that is adapted to maintain a pressure within said first and second satellite screw extruders below about 18 millibars; (i) a first satellite screw extruder, said first satellite screw extruder comprising a first satellite screw that is mounted to rotate about a central axis of said first satellite screw; (ii) a second satellite screw extruder, said second satellite screw extruder comprising a second satellite screw that is mounted to rotate about a central axis of said second satellite screw; and (iii) a pressure regulation system that is adapted to maintain a pressure within said first and second satellite screw extruders below about 18 millibars; using said pressure regulation system to reduce a pressure within said first and second satellite screw extruders to below about 18 millibars; after said step of passing said plurality of flakes through said PET crystallizer, while maintaining said pressure within said first and second satellite screw extruders below about 18 millibars, passing said polymer melt through said multi-screw extruder so that: a first portion of said polymer melt passes through said first satellite screw extruder, and a second portion of said polymer melt passes through said second satellite screw extruder; and after said step of passing said polymer melt through said multi-screw extruder, forming said polymer melt into bulked continuous carpet filament.