Palm oil physical refining process(3)
Palm oil physical refining process can be divided into 3 parts: pretreatment process, steam refining and deodorization process, and fractionation.
Palm oil physical refining process
Fractionation of palm oil physical refining process:
In palm oil physical refining process, fractionation process consists of a controlled cooling of the oil, thereby inducing a partial, or ‘fractional’, crystallization. The remaining liquid (olein) is then separated from the solid fraction (stearin) by means of a filtration or centrifugation.
The picture presents a general lay-out of a present-day fractionation process. Often multiple crystallizers are used in (overlapping) series. This is not only a matter of capacity, it is also in order to maximize the use of the filter; by a good planning of the crystallization times of filtration, the expensive (batch) filter should be in constant operation.
It should be kept in mind that fractional crystallization of a triglyceride oil is a relatively slow process and is therefore the time determining stage; some simple fractionations can be established in about 5hr crystallizer residence time, whereas more complex oils can require up to 3 days of cooling and crystal maturation before being sent to the filter.