A REVIEW OF FUNDAMENTAL AND ENGINEERING ASPECTS OF EXTRUSION OF BIOPOLYMERS IN A SINGLE-SCREW EXTRUD

A review of fundamental and engineering aspects of single screw extruder is given. Attention is focussed on flow patterns, flow rates, residence time distributions and power consumption as a function of extruder design and screw rotation speed. The relationship for these engineering variables in extrusion of a purely Newtonian liquid and a power law liquid are reviewed. Where possible these relationships are compared with experimental results from the literature (corn-grits) and with our own measurements on biopolymers (corn-grits, defatted soy flour, modified di-amylopectin).