Abstract: A counter current extractor including an elongate housing with a screw conveyor therein and having a strainer at one end thereof to filter a liquid phase out of the counter current extractor, wherein the strainer is provided with a clearing member to prevent the strainer from remaining clogged with particulate material and wherein liquid being fed into the counter current extractor is spilled into the extractor so as to flow in a cascade over and through a solid phase in the extractor, the liquid being maintained at a desired level by a control member.