A Comparative Study of Residence Time Distributions in a Kneader, Continuous Mixer, and Modular Intermeshing Co-Rotating and Counter-Rotating Twin Screw Extruders

Abstract

Abstract Residence time distributions were measured for a Buss Kneader, Kobelco Nex-T continuous mixer as well as intermeshing co-rotating and counter-rotating twin screw extruders using polypropylene with aluminum flakes as a marker. Various modular screw configurations, screw speeds and feed rates were considered. Increasing feed rate and increasing screw speed the mean residence to shorter values and narrows the residence time distribution. Generally, in comparison of the different machines, the intermeshing counter-rotating twin screw extruder has the shortest mean residence time and narrowest distribution of residence times, while the Buss Kneader has the longest mean residence time and broadest residence time distribution.