Oilseed preparation is a critical step in the entire process because the efficiency of all downstream processes, including the quality of the extracted oil and meal, depends on it. Here, the oilseeds are cleaned and processed mechanically and/or thermally to make the seeds ready for pressing to ensure maximum pressing efficiency.
We offer complete equipment and process technology for all types of oilseeds – right from bulk storage, weighing, cleaning, destoning, dehulling, cracking, flaking, and conditioning.
We will work with you at every step of the process – right from undertaking complex modeling to find optimal solutions to conducting pilot testing if needed to ensure your installation is both seamless and optimized.
The first step to preparing the seed for extraction is cleaning. The seeds are cleaned in specially designed seed cleaners that filters impurities such as leaves, dust, stems. The seed cleaner is usually a multi-deck machine capable of segregating the different factions. The cleaner also contains an aspiration system that removes other lighter particles, like dust, loose hulls etc.
Depending on the stage of the oilseed storage, we offer both pre-cleaners and post-cleaners.
Pre-cleaners clean seeds before storage. Post-cleaners are used to clean seeds after storage but before processing. Seed cleaners can be mechanical, mechanical and pneumatic, or rotary drum types. United offers seed cleaners with variable speeds and flexibility (from 1TPH to 20 TPH, depending on the type of seed) to ensure smooth flow of seeds.
Destoning removes seed-sized stones which have not separated from the seeds after screening. It is based on the principle that stones and seeds have different densities (stones are heavier than seeds). The system consists of a vibratory sieve and an aspiration system (vacuum-based) built on an adjustable sloping deck. The units we offer includes a cyclone fan and an inspection window to check progress. An air-locked steel box frame ensures there is no dust emission.
Dehulling means ‘removing the hull.’ It is undertaken on certain oilseeds to improve the quantity of extracted oil and quality of the meal and is done by feeding the oil seeds to specialised equipment depending on type of seed.
It can be either a warm or hot process. Hot dehulling is suitable for oilseeds that have up to 14% moisture. Dehulling also reduces the quantity of fiber in the processed meal, leading to more protein content.
Cracking is a form of seed breaking and is done prior to pressing.
During cracking, the oilseeds are crushed in a cracking mill, which can be adjusted to reduce the oilseeds to a certain size. Typically, there will be many cracking rolls stacked vertically, one above the other, so that after the first roller has crushed the seeds, they are gravity fed into the second cracker and third cracker until the oilseeds are reduced to the desired size.
Some oilseeds, such as rapeseeds and sunflower, contain a higher percentage of oil, and for higher capacity plants, its critical to flake the seeds to ensure a higher efficiency of extraction. Prior to Flaking seeds are usually conditioned, and flaking ensures a deformation of the seed particles into thinner flakes, which rupture the seeds oil cells, making them accessible to the extraction process.