Solvent extraction of solids - by percolation through solids bed across which pressure gradient is set up

摘要

In extracting raw materials from solids by percolating solvent through a bed of the particulate solid the solvent percolation is accelerated by setting up a pressure gradient across the bed. In a conventional rotary extractor the extraction zone is maintained at a higher pressure than the collection zone for the percolated solvent. This is achieved with a dividing plate between the zones whose edges are sealed and which has narrow openings, which taper upwards towards the extraction zone, for passage of the solvent.