US Patent 8163945 Extraction of oil from food wastes

Raw material such as food waste is scanned by a metal detector (11) and objects or containments removed, the food waste is then ground or macerated by a disintegrator (13), and passed to a live steam kettle (14), then passed to an in-line heater (15) wherein it is raised to and maintained at 80% for 20 minutes. The product is pumped to a three-phase decanter centrifuge (16) where it is separated into solids, water waste and tallow (oily product). The latter is pumped to storage tank (20), using a centrifugal pump (21), while water waste is discharged to effluent while solids are discharged to a container (18).