Method of removing liquids from solids

A method of removing a liquid from a mass of a material which is capable of being transported and worked by an extruder having a barrel-screw combination, wherein the method comprises:

• transporting the liquid-containing material with a first barrel-screw to a liquid-extraction location within the first barrel, the first barrel-screw applying to the material first transporting and working forces which are generally applied in a first direction;
• applying second transporting and working forces to the material within or slightly downstream of the liquid-extraction location, the second forces being applied in a second direction which is generally opposite the first direction, the application of the first forces and the simultaneous application of the first and second forces to the material tending to compact the material to extract therefrom the liquid contained therein;
• permitting the extracted liquid to exit the first barrel from the liquid-extraction location along a path which extends away from the liquid-extraction location generally transverse to the first and second direction;
• and
• preventing the material from traversing the path by applying third transporting and working forces thereto along the path in a direction generally opposite to that taken by the exiting liquid, the application of the third forces being ineffective to prevent the exiting of the liquid,
• the first, second, and third forces effecting a pinch point on the material within or slightly downstream of the liquid-extraction location to substantially obviate liquid flow countercurrent to said first direction.