A British recycling company has found an interesting application for the MRS Extrusion System from Gneuss (U.S. office in Matthews, N.C.). K2 Polymers Ltd. in Loughborough, U.K., which specializes in recycling engineering resins, is using the MRS (Multi Rotation System) to reprocess nylon 11 regrind heavily contaminated with oil.
The regrind came from deep-sea oil pipes that were scrapped after having been recovered from the sea floor at a depleted oilfield. Some oil was on the surface of the material and some had diffused into the polymer itself. The MRS extruder was able to carry out processing and decontamination in one step, eliminating the need for prewashing. The machine was able to extract the oil because of its extremely high devolatilizing capacity (approximately 25 times greater surface-area exchange rate under vacuum than an equivalent twin-screw extruder), Gneuss reports. An efficient vacuum system required only 25 to 40 mbar of vacuum to remove the oil and volatiles from the melt.
K2 Polymers usedthe MRS 70 with a throughput rate of up to 330 lb/hr. The reprocessed nylon 11 will be used for automotive vacuum and compressed-air hoses. The system included a Gneuss RSFgenius Rotary Melt Filtration System.