Performance Evaluation of Floating Fish Feed Extruder

Abstract

The performance of a developed floating fish feed extruder was evaluated. The effect of some parameters such as; screw speeds (100 rpm; 150 rpm; and 200 rpm); moisture content of ration (20 %; 25 %; 30 % and 35 %); and die diameters (3 mm; 5 mm; 9 mm) on specific mechanical energy requirements; expansion ratio; bulk density and pelleting efficiency were determined. Results showed that increasing the screw speed from 100 rpm to 150 rpm tend to increase in extrusion efficiency from 63.25 % to 68.50 %. And decrease in bulk density from 1.05 g/cm3 to 0.94 g/cm3; decrease in specific mechanical energy from 24.70 kJ/kg to 22.30 kJ/kg. By increasing the die diameter from 3 mm to 5 mm; the specific mechanical energy tends to reduce from 28.44 kJ/kg to 26.46 kJ/kg; reduce bulk density from 1.05 g/cm3 to 0.97 g/cm3. And increase extrusion efficiency from 63.25 % to 68.00 %. Results also showed that increase in moisture content from 20 % to 25 % tend to reduce the specific mechanical energy from 28.44 kJ/kg to 24.99 kJ/kg; reduce bulk density from 1.05 g/cm3 to 1.01 g/cm3. And increase the extrusion efficiency from 63.25 % to 72 %.