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Knowing the change in AT product temperature at the appropriate n can
determine the amount of heat released as a result of the dissipation of
mechanical energy of the extruder working bodies.
The pressure in the product zone of the extruder before matrix decreases
hyperbolically with the increase of its initial moisture. Moreover, the greater the
passage section of the matrix area, and the content of protein supplement
(SOMO), the sharper the reduced pressure of the melt extrudate. On the specific
energy consumption has the greatest impact factor of the living section of the
matrix, and the smallest - design parameter (compression ratio of the screw).
And with the increasing pressure of the product and the speed of the screw
increase the specific energy consumption. Studies have shown that the intensity
of evaporation, which determines the speed of the process flow and productivity
of the extruder, to the greatest extent affects the auger speed.
With the pressure of the product increasing the intensity of moisture
evaporation is markedly increased.
Character modeling extruding food mixtures does not contradict the
theoretical foundations of single-screw extrusion process.
Preparation crisp bread and potato sticks possible at low screw rotation
angular velocities (less than 10.47 "1).
Unit cost of electricity for carrying out the process is in the range
comparable to the cost of electricity foreign industrial extruders.
Basic laws of twin-screw extrusion process cereal extrudates with constant
heat input (0,068 W/mm2), and change the speed of the screws influenced the
decrease in temperature, so you need to report an additional amount of heat to
maintain a stable temperature of the product before matrix zone. The drop in
temperature is linear, indicating the release of heat by internal friction forces
have a similar appearance.
When excessively large diameter channel before matrix zone is not formed
enough pressure, and moisture does not accumulate the energy required for a
good swelling of the extrudate. When changing the ratios of starch and protein in
the mixture extrudable buckwheat and soybean last downward pressure
reduction occurs in before matrix zone. The viscosity of the starch phase below
the protein, and thereby decreases the viscosity of the overall mixture.
Reduction of swelling in protein content of more than 30% due to increased
viscosity of the medium. The greatest impact on the product melt pressure render
the design parameters of the extruder (the diameter of the passage section of the
matrix), and the initial moisture content of the model cereal mixture; geometrical
characteristics of the working body, the angular velocity of the screws and
maximum product pressure to affect the temperature of the matrix before the
zone of the extruder.
Single-screw machines - extruders of friction, the heating capacity for their
effective work required is less than for the same performance twin-screw auger
with full engagement. With the increase of the linear product of the channel
matrix output speed performance increase occurs extruder. In twin-screw
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