AIR CLASSIFICATION OF ANIMAL BY-PRODUCTS

• Main Author: PLAS, STEPHEN JEFFREY
• Format: Patent
• Language: English; French
• Published: 30.08.2005
• Edition: 7
• Subjects: APPARATUS FOR PREPARING ANIMAL FEEDING- STUFFS; FOODS OR FOODSTUFFS; HUMAN NECESSITIES; MACHINES OR APPARATUS FOR TREATING HARVESTED FRUIT, VEGETABLESOR FLOWER BULBS IN BULK, NOT OTHERWISE PROVIDED FOR; OTHER SEPARATING BY DRY METHODS APPLICABLE TO BULK MATERIAL,e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL; PEELING VEGETABLES OR FRUIT IN BULK; PERFORMING OPERATIONS; SEPARATING SOLIDS FROM SOLIDS; SEPERATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, ORSIFTING OR BY USING GAS CURRENTS; SORTING; THEIR TREATMENT, NOT COVERED BY OTHER CLASSES; TRANSPORTING

The utilization of an air cyclone classifying method to effectively separate out a low ash fraction, containing less than 11 % by weight of non-protein material, from rendered animal meal. A yield of low material greater than 50 % by weight is recovered as usable canine and feline food. The method involves the creation in a first cyclone separator (10) of a double vortex air cyclone having a descending external air vortex (20) and a rising internal air spire (22); wherein an upper chamber (11) therein is equipped with a rotary particle rejector (13). The rendered animal meal infeed is fed into the rising air spire (22) which entrains and carries the low ash fraction through the rotary particle rejector (13), to a second cyclone air cleaning device (26); wherein the low ash material (23a) is recovered from the entraining air. The larger and denser high ash particles (41) are recovered from the first cyclone separator.