Superfine® Air Classifiers have been used for decades to shift the protein value of wheat flour. Sturtevant Simpactor® pin mills or Powderizer® air classifying mills can be teamed with a Superfine® Air Classifier to obtain fractions precisely selected for particle size, starch protein level, viscosity, or absorption.
Sturtevant flour refining systems offer full operating flexibility and high capacities. With this system, precise separations are easily achieved for protein shifts, primary classifications, coarse and fine separation for new end products; in one operation and no matter what the wheat source. Supplemental recycling and blending make individual specifications. A similar process can also be used for other grains including peas, corn, soy, barley and oat.
Application: Wheat, peas, corn, soy, barley and oat protein fractionation, modified and specialty flours.
The Method of Operation
Material to be classified is fed through a top-mounted inlet and falls directly to a distributing plate which spins the material laterally, forming an “umbrella” of thinly spread particles. Carefully controlled ascending air currents carry “fines” upward to the final selection zone. Here rejecter blades emit centrifugal force which acts to preclude oversize particles entering the “fines” chamber. Oversize low protein flour drops out of the tailings cones while high protein flour “fines” are exhausted to a cyclone or bag collector.
Function
The air classifier has two distinct functions: first, it may be employed to select fine particles as the desired product; second, it can de-dust a coarse product. In either case, the product selected can be varied by external control of the air velocity.
Use
By its ability to “cut out” a fines fraction from the carefully selected patent flour stream, the air classifier provides the means to alter the protein percentage in the end products. The miller can also use the protein rich “fines” to enhance other streams.
The net effect is to allow the soft wheat miller to use the wheat grown in the immediate area to produce flour for the miller’s special needs.
For the hard wheat miller, the air classifier offers the opportunity to divide-off a high protein fraction. This must in turn be reground and classified to finally produce a high protein, clear fraction and a specialty low protein, “sweet goods” fraction.