Extractors

One of the most common and effective methods of extracting vegetable oils from the seeds of oil crops used in industrial enterprises today is the technology of oil extraction using organic solvents. This technology allows obtaining oil and high-protein meal with a residual oil content of less than 1%. The heart of this technology is extractors, which have been produced by “TAN” company for more than 10 years already.

The extractor is used to separate the oil from the cake granules of oil crops using an organic solvent. Depending on the design and principle of operation, the extractors can be divided into several types:

– tape;

– screw;

– plate-shaped;

– carousel (in other words – rotary).

Extractors produced by the company “TAN” are of the carousel type.

The carousel extractor is a cylindrical device, consisting of one or two storeys with an internal rotor. The rotor consists of a number of segment cells that are continuously loaded with extracted material. Material in the form of granules is supplied from the expander to the feeding bunker of the extractor with the help of a screw conveyor. The cells move along stainless steel slotted bottoms, in which the gaps between the rods increase downwards. This design eliminates the risk of clogging of the grid with material particles and allows the solvent or miscella to escape freely from the material layer, and, accordingly, to extract oil more efficiently. The extracted material is discharged into a gas-tight bin, which is part of the extractor. The bin is equipped with a screw conveyor that feeds the extracted material (meal) to an inclined scraper conveyor (“gooseneck” type), which in turn feeds the meal for further processing into the toaster.

The solvent is fed into the extractor countercurrently to the direction of rotation of the extractor. The liquid solvent seeps (percolates) through the layer of material and the grid bottom into the lower part of the extractor (miscella collector), which is divided into several segmental compartments designed to collect the miscella and transfer it to the pumps. Each segment has its own pump. These segmental compartments separate miscella of different concentration and prevent it from mixing. Miscella is fed by pumps through the nozzles into the extractor from above the raw material, passes (percolates) through the layer of raw material, dissolving the oil, and flows through the grid bottom into the next segment of the miscella collector. Thus, miscella moves countercurrently to the raw material, increasing the oil concentration. The concentrated miscella from the extractor is fed into miscella tank from where it is fed by a pump into the distillers for the solvent removal, and its further condensation in condensers.

The extractor drive consists of an adjustable speed motor, a worm gear box and a chain around the extractor rotor. The rotation speed of the extractor is regulated depending on the amount of material supplied.

The carousel-type extractors produced by “TAN” company have a number of advantages:

• constant level of material in the cells, regardless of the speed of product supply;
• uniform extraction;
• permanent sealing;
• the possibility of increasing the capacity of the extractor by adding storeys.

“TAN” company manufactures fully automated extractors and complex extraction lines. The electronic control system consists of a large number of sensors, a programmable controller (PLC) and frequency converters. The control system also synchronizes the speed of the extractor’s feeding screw, the extractor itself and its discharging screw, allowing control of the entire material flow and guaranteeing a constant level of material in the cells and uniform extraction. Also, complex automation allows achieve compliance with all necessary safety standards, as well as other standards for high-risk areas in the production of vegetable oils

“TAN” company produces extractors of three capacities: 250 tpd, 500 tpd and 1000 tpd based on sunflower seeds. More detailed technical characteristics of carousel extractors manufactured by TAN LLC are given in the table below: