Pretreatment is necessary for efficient oil extraction from raw palm kernel. In palm kernel oil industrial production, oil raw materials are usually palm kernel or pressed cake. If the material is palm kernel, the main pretreating steps are palm nut cleaning, shelling and separation, crushing, flaking and steamed frying. If your raw material is a press cake from palm oil press workshop, you need to do this: The material cake should be cracked by a screw conveyor and conveyed into a fiber separator drum for fiber separation. After these simple treatment, you can get cleaner palm kernel, the rest of the process is the same:
Palm Nut Cleaning
The raw palm nut’s impurity should be cleaned firstly otherwise it would cause damage to the screw press machine. The magnetic selector is installed for removing metal debris, while the vibrating sieve is used for removal of sand, fines or other undesirable impurities. And the stones could be removed by gravity stoner.
Palm Nut Shelling and Separation
By palm kernel husking and separating system, the clean palm nut is cracked and divided into palm kernel and shell. First of all, the palm nut is husked by our high-quality palm nutcracker with a husking rate of 85-95%. Next, the cracked shell and kernel are separated by air separator machine, through the air duct, shell and kernel could be firstly separated onto V-shaped screen’s upper layer and the lower layer, finally, the rest kernel on the upper layer could be dropped from the screen holes by screen vibrating. After separating, the kernel content in the shell and the shell content in the kernel are less than 5%. Shelling can increase the oil yield, improve the quality of crude oil & cake, reduce abrasion of equipment and increase the effective production of equipment. The palm shells are always sent to the boiler room for fuel use.
Since palm kernel is relatively large and hard, in order to better improve the oil yield, the palm kernel needs to be secondary crushing after husking. The main crushing equipment is rolling crusher, which can break kernels into small pieces and easy to produce oil. It has a simple structure, stable performance and easy to operate.
Flaking machine is mainly made up of two or more opposite rotating rolls (high nickel chrome molybdenum alloy). When the kernel pieces are in the middle of the two rollers, they are squeezed by instantaneous pressure to form flakes, meanwhile, the crude oil is rolled out firstly. This machine is widely used in oil plants and individual oil processing mill, easy to operate and maintain. After flaking, the palm kernels are easy to be steamed.
The purpose of steamed cooking is to completely destroy the oil cells by high temperature and moisture, so that the protein is denatured, the oil is steamed out and collected, the viscosity and the surface tension of the oil are reduced, the elasticity and plasticity of the material are adjusted, and the enzymes are passivated. Steamed cooking equipment is a steam frying pan, which can process the raw palm kernel flakes into matured flakes by heating, spraying and steaming. The equipment can also be used as a softening pot, softening can improve the quality of rolled flakes, thereby increasing the oil yield, and can improve the quality of crude oil. It is the necessary equipment for vegetable oil factory.