Growing activity in carpet recycling has prompted new modifications in counter-rotating, twin-rotor continuous mixers. Technical Process & Engineering Inc. (TPEI), of Lehighton, Pa., has built continuous mixers for 30 years. They recently introduced a patented rotor design for hard-to-recycle, low-bulk-density materials like carpet fiber and film (U.S. Pat. 7350960, Apr. 2008).
Two of its model 9FRE mixers have been sold to compound and pelletize recycled PP carpet fiber at the rate of 4,000 to 8,000 lb/hr. The beefed-up mixing rotors have a first section with Lowenherz, or V-shaped, threads scored in the outer periphery of the rotor to increase feed rate, followed by standard melting screw flights, which feed into a wing-type helical mixer in the second half of the rotor. A patented pneumatic seal (U.S. Pat. 6390666) with a stepped metallic sleeve improves the rotor's upstream seal by purging contaminants before they reach the seals.
TPEI's continuous mixers are supplied as a unitized system with the mixer feeding a continuous ribbon directly into the throat of a single-screw discharge extruder for pelletizing or direct extrusion. The transition between mixer and discharge extruder includes a proprietary "J-Block" feed section for even flow of material into the extruder without surging, eliminating the need for metering or melt pumps.
Technical Process & Engineering Inc. is a one-stop source for plastics and rubber processing equipment and associated technical support. After nearly 30 years, TPEI continues to provide superior quality machining, fabrication, engineering, and technical support services to the plastics and rubber processing industries. From rotor repairs and restacking; machine alterations and rebuilds; to the design and fabrication of complete "turnkey" mixer / extruder / pelletizer / dryer systems; TP&E is the one-stop answer to keeping your facility running profitably.
892 Blakeslee Blvd. Drive West
Lehighton, PA 18235
Phone (570) 386-4777
Fax (570) 386-4120