This process utilises a two-stage evaporator as cooker and dryer. This is made possible by using re-circulated fats as a carrier liquid. The process offers very high digestibility due to relative short retention time and cooking temperatures as well as low steam consumption due to the utilisation of waste heat in the second stage of the slurry evaporator.
The slurry process can be made even more energy efficient through the addition of a third effect if waste heat from e.g. a disc dryer is available as energy source.