Immersion vs. percolation in the extraction of oil from oleaginous seeds

摘要

The influence of the two contact modes, percolation and immersion, during the extraction of oilseeds by means of a solvent are presented. Experiments were performed in lab-scale equipment with soybean flakes, arranged in beds that reproduce these two contact modes. The extractions were carried out with hexane at constant temperature. To simulate the performance of shallow- and deep-bed extractors, two different bed height/diameter ratios were used. The experimental results are explained in terms of the basic transfer phenomena that occur during extraction. These phenomena are addressed to develop a mathematical model, which is used to simulate extraction under both contact modes. The immersion scheme yielded greater efficiency than the percolation mode to extract soybean flakes for the two bed height/diameter ratios studied. The mathematical model predicts very well the experimental findings. It also predicts the solvent retained by the solid mass after extracting the oil. [References: 21]