The main aim of this research was to develop a mathematical
model of heat and mass balance of pre-conditioning and
extrusion stages to predict the temperature, moister content and
energy requirement of the feed production at different heating
temperatures and feeding rates. To achieve that, the effect of
temperature and mass flow rate of water and oil in
preconditioning on energy rate of preconditioning, mass flow
rate of production, mass fraction of moisture of production, and
energy rate of product were studied. The results indicate that the
energy rate of preconditioning ranged from 523.4 to 8164.7 kJ
h-1 and 209. to 3266.3 kJ h-1 for water and oil, respectively,
the energy rate carried by water injection into extruder
increased from 352.5 to 916.5 kJ h-1. The mass flow rate of
production increased from 144 to 174, 133 to163 and 119 to179
kg h-1 for water, oil and water and oil, respectively. The mass of
moisture of production ranged from 0.2 to 0.34, 0.32 to 0.26,
and 0.24 to 0.3 kg h-1 for water, oil and water and oil,
respectively. The temperature of product ranged from 159 to
174, 180 to163 and 185 to179 °C for water, oil and water and
oil, respectively. The energy rate of product ranged from 52590
to 60795.3, 54616 to 57672.9 and 50708.2 to 61970.3 kJ h-1
when the temperatures increased from 25 to 65°C, respectively,
at 5 and 30 kg h-1 mass flow rate.
|
