LLL extractor
The Desmet LLL extractor is the third type of large capacity extractors in the Desmet portfolio. ‘LLL’ stands for Low Level Linear extractor. This extractor differentiates from the Reflex and LM extractor, since it is a shallow bed extractor with layer heights between 0.5 and 1 m.
The Desmet LLL extractor is a double deck horizontal shallow bed percolation extractor where the material is transported through the extractor by a robust but simple chain with paddles that pulls the material over the fixed wedge bar floors of the upper and lower part of the extractor.
The material is extracted by spraying hexane in counter current over the extraction bed. The miscella is collected in up to 16 miscella hoppers under the fixed floors and from there pumped to the next extraction stage.
The shallow bed allows the extraction of low percolating material A typical application is the extraction of thin soybean flakes.
The working principle of the LLL extractor is explained in more details hereunder.
How does it work
The feedstock coming from the preparation plant enters the extractor through the inlet feeding hopper at the upper part of the extractor.
The material is transported through the upper part of the extractor by the chain with paddles. At the end of the upper part the partially extracted material falls through a chute to the lower part of the extractor, hereby restoring the percolation rate. No material is entering the chain return elbow. The material is then again transported with the chain through the lower part of the extractor for further extraction. After a dripping zone, the extracted material then falls in the outlet hopper, situated at the same side as the inlet hopper, for transport to the desolventizing section of the extraction plant.
During the transport trough upper and lower part, hexane is sprayed in counter current over the extraction bed. The miscella is collected in up to 16 hoppers under the fixed wedge bar floor and from there pumped to the hexane sprayers of the next extraction section. This creates a very efficient counter current extraction.
The LLL extractor is a very flexible and forgiving extractor. Extraction time can easily be adapted by changing the chain speed. This extractor is especially recommended for difficult to extract material with low percolation rates. A typical example are thin soya flakes but also a lot of other materials can be successfully extracted.
