There are three methods of extracting Palm kernel Oil
- Mechanical Extraction
- Solvent Extraction
- Traditional Method
This extraction method can be used for any enterprise be it large or small scaled operations. It involves three simple methodologies
- Pre Treatment of Kernel
The process of solvent extraction involves three simple methodologies Pre Treatment of Kernel, Extraction of Oil and recovery of solvent from the meal and oil. This process is not recommended for small businesses. It is much more suitable for high capacity operations.
It’s important to clean the feed kernels of foreign elements to avoid damage to the presses. Common elements that are removed are metal debris, sand, and stone. Then the kernels are broken into smaller fragments. The kernel fragments are then fed into a large roller mill where the thickness of the kernels is reduced producing flakes
The kernel flakes are then steam conditioned in order to adjust the moisture content of the meal, rupture cell walls, reduce oil viscosity, and coagulate the protein in the meal to facilitate separation of the oil from protein materials
- Screw pressing
The cooked meal is then fed into the screw press where it is compressed. The expelled oil drains through the perforation of the lining bars while the oil free cake is discharged through the annular orifice
- Oil Clarification
The oil is drained to a reservoir then channeled through a decanter or coarse screen to remove solid impurities. The oil is also further passed through a filter press to remove left over solid particles to produce a clear oil which is then stored. The cakes are also discharged to storage.
The process of solvent extraction involves three simple methodologies. Pre Treatment of Kernel, Extraction of Oil and recovery of solvent from the meal and oil. This process is not recommended for small businesses. It is much more suitable for high capacity operations.
This methods starts when the palm nuts are shelled. Previously, this shelling process was done by manually cracking each nut with two stones by hands. However, this labour intensive process has been largely replaced by the use of nut-cracking machines
Cracking of the nuts gives a mixture of kernels and shells which have to be separated. This separation is done in a clay-bath, which has a concentrated mixture of water and clay. This bath is designed such that the shells sink to the bottom while the lighter kernels float to the top of the mixture. The kernels are then scooped with strainers or baskets, purified with clan water and then dried.
Oil extraction is done by frying palm kernels in old oil or simply heating the dried nuts. The fried palm kernels are then pounded or ground to a paste in a grinder. The paste is mixed with a small quantity of water and heated to release the palm kernel oil. The oil produced periodically skimmed from the top.