C2C Technology for Passenger Car Tire Rubber by a Continuous Devulcanization Process
Wilma K. Dierkes, Johannes Wilhelmus van Hoek, Sitisaiyidah Saiwari, Louis A.E.M. Reuvekamp, G. Heideman, Anke Blume & Jacobus W.M. Noordermeer
Location
University of Twente
Link:
Abstract
As a means for decreasing the amount of waste tires and for re-using tire rubber for new tires, devulcanization of ground passenger car tires is a promising approach. Being an established technology for NR and EPDM, earlier work has shown that for ground passenger car tire rubber with a relative high percentage of SBR, a devulcanization process can be formulated too. This was proven for a laboratory scale batch process in an internal mixer, using diphenyl disulfide as devulcanization aid and powder-sized material. In this study, the devulcanization process for passenger car tire rubber is further scaled up and transformed into a continuous process in a co-rotating twin-screw extruder. As SBR is rather sensitive, the screw design was based on a low shear concept. A granulate with a particle size from 1 to 3.5 mm was a chosen as feedstock. The devulcanization was fine-tuned in terms of process conditions, extruder parameters, and ancillary equipment. The influence of these parameters on the devulcanization efficiency and the product quality will be discussed, based on the Horikx concept. A best practice for a continuous devulcanization process in this type of extruder will be given.