Research On Structure Design And Effects Of New Extruder For Sinking Aquafeed

Compared to common floating aquafeed, the relative low production efficiency, which results in high production cost, is one of the disadvantages for producing sinking aquafeed with an extruder. Meanwhile, the existing extrusion method for sinking aquafeed, which limits the product's expansion extent under a low-temperature and low-pressure condition, cannot result in high gelatinization of the extruded product, neither further enhance the animal digestion. Limited by these two factors, the promotion of such technology is still not so ideal.This thesis studies the feasibility of producing sinking aquafeed efficiently by equipping a cooling zone on a common extruder which is normally used to produce floating aquafeed. First of all, extrude and ripen the material in the extruder under a high-temperature and high-pressure condition with the same processing parameters for producing floating aquafeed, then reduce the temperature of the material in a dispersive cooling way so as to inhibit expansion, and obtain a sinking aquafeed with required bulk density.In this study experiments were carried out by furnishing a MY165 single screw extruder with a cooling zone based on three different technical parameters. And the result shows that compared with those main technical parameters adopted in the conventional technologies for producing sinking aquafeed and floating aquafeed, equipping a cooling zone with a cooling time of I Is to extrude sinking aquafeed, can raise the production efficiency from the original 1400 kg/h to 3200kg/h with an increase of 228.6%, while reduce the unit power consumption from the original 68.6 kW·h / t to 44.75kW·h / t with a decrease of 34.77%. And the gelatinization of the sinking aquafeed can be enhanced from 70.5% to 91.6%, similar to that of the floating aquafeed.