Dewaxing or Winterization is a process to remove solids (saturated glycerides or waxes) from oil. These solids cause cloudiness in oil at low temperature.
This process is suitable for oils like Sunflower Oil, Cottonseed Oil, Corn Oil, Ricebran Oil etc which have wax contents more than permissible limit.
The oil is mixed with filter-aid and is cooled at desired temperature in Crystallizers. Crystallizers are equipped with agitator to bring first crystals into contact with more oil to make bigger crystals.
It also has cooling coils which ensures gradual cooling of oil to the crystallization temperature. After the desired crystallization time, the oil mass is filtered in plate and frame filters/horizontal PLF/gravity filters where crystallized waxes separate from oil.