Modern LTR – low temperature protein processing plants for fishmeal and rendering use a 3-phase decanter centrifuge to separate press water into oil (tallow), stick water and fine sludge solids.

  • The oil (tallow) is further clarified in a high speed separator polisher to contain about 0.2% solids and water
  • The fine sludge solids are sent to the disc dryer
  • The stick water which is the largest volume will be sent to the WHE – waste heat evaporator for concentration before going to the disc dryer.

The advantage with using 3-phase decanter is that the machine can be adjusted to produce clean stick water with a minimum of oil before going to the WHE and dryer, and thereby secure minimum of fat in the finished meal.

The oil with come out with a higher percentage of water that will be removed in the separator polisher.

Decanters are high speed machines that need special care, cleaning, lubrication and relative frequent change of bearings (every 1 – 1.5 years or so) by qualified technicians.
Two phase decanter is being used when only solids and liquid(s) are to be separated, such as hot tallow (oil) coming from a high pressure press in HTR – high temperature rendering plants and in blood meal plant to separate coagulated blood cake and stick water.