Extraction process

摘要

A process for the continuous extraction of water soluble solids from solid particles containing them for providing an extract product in one or more extraction stages. In each extraction stage, a slurry containing particles to be extracted and extract is introduced into an extraction reactor e.g. immediately above a solid-liquid separator to form an upwardly moving packed bed. Particles are scraped from the packed bed for defining an upper surface of the packed bed. An extraction liquid is introduced into the extraction reactor above the upper surface of the packed bed. A portion of the extraction liquid percolating through the packed bed for extracting water soluble substances from the particles in the packed bed and forming an extract. The remaining portion of the extraction liquid entrains the particles scraped from the packed bed for providing a spent particles slurry. The spent particles slurry is removed from the extraction reactor. Extract is removed from below the packed bed and at least a portion of the extract forms the extract product. The extraction stages may be separated by one or more solubilization stages. Examples of water soluble substances are soluble coffee solids or soluble tea solids. <IMAGE>