incrust EV Line
DESCRIPTION:
The incrust EV process is relates to a method for energy-saving extruder cooking of animal feed and takes place by dividing a feed mixture into a starch part and a primary part. The starch part, which normally constitutes 20-30% of the entire feed mixture, is fed to a continuous extruder cooker, where the starch part and steam is mixed and extruded at high pressure and temperature until a sufficient gluing and thermoplastic state is obtained.
Subsequently, the starch part is passed, through a venting zone, at atmospheric pressure, where the sudden pressure drop causes an evaporation and temperature drop so that the water content in the starch part decreases.
After the venting zone, the unheated primary part of the feed mixture with low water content and room temperature is added.
The starch part and the primary part are passed through a mixing zone where the two products are mixed homogeneously into a finished product.
After the mixing zone, the finished product is passed with increasing pressure and temperature through a matrix into a vacuum chamber, where the pressure is reduced from 1000 to 100 millibars depending on the desired density and porosity of the pellet. The residence time of the feed pellets in the vacuum chamber is varied according to the density and porosity desired.
The sudden drop in pressure causes an evaporation and temperature drop so that the water content of the finished product decreases.
Experiments have shown that the pellet temperature drop falls from co. 90 to approx. 50˚C when the pressure (inside the pellet chamber) is reduced from 1000 to 200 millibars. At the same time, the pellet becomes more porous after the negative pressure treatment, as the density (less weight per volume content) decreases from 450 to 280 grams per liter pellets. Other experiments have shown that pressures lower than 200 millibars also have a beneficial effect on the control of the porosity of feed pellets.
Compared to the extruder cooking process used today, where the feed mixture is not divided, great energy savings are achieved:
incrust 