Production of olive oil
Horizontal centrifuge or decanter
The paste, in the form it leaves the beater, goes to the decanter, which contains horizontal centrifuge separators.
The horizontal centrifuge or decanter is a horizontal cylinder, tapering out at one of its ends, which contains an endless screw (spiral), which draws the paste inside.
The decanter separates the oil from the paste, via the centrifugal force, using the extremely high rotational speed and the different specific weights of the various phases for separation (oil and water plus the olive pomace).
The centrifugal force makes the pomace (the chopped olive stone), mixed with the wash water, accumulate in the tapered part of the cylinder and, from there, it exits via a valve. The same centrifugal force pulls the oil to the opposite end due to its different specific weight. From the decanter, the oil passes to the vertical centrifuge.
The water added to the paste must have a temperature of approximately 26ºC to help centrifugation.
The greater the quantity of vegetation water contained in the olives, the lower the amount of water that needs to be added.
This system is thus called “two-phase” because it separates the oil on one side and the pomace and water ( alperujo) on the other.
The oil leaves the horizontal centrifugal separator or decanter, and makes its way to the vertical centrifuge or centrifugal separator.