Abstract: In an extruder for processing material to form an extruded product, the extruder including an elongated extruder barrel having a material inlet end and an outlet end remote from the inlet end, and a pair of elongated, axially co-rotatable, flighted extrusion screws within the barrel for moving materials from the inlet end towards and through the outlet end, the barrel is provided with a pair of parallel bores which are formed with spiral grooved surfaces along at least a portion of their lengths. An inlet opening is provided adjacent the inlet end of the barrel such that one of the co-rotating screws of the extruder rotates in a direction outward and downward from the inlet opening and the other screw rotates upward and toward the inlet opening. The bore receiving the upturning screw is provided with a smooth surface region adjacent the opening which prevents material entering the inlet opening from being delivered back into the opening by the upturning screw.

Abstract: A greatly improved twin screw extruder and method are disclosed which significantly reduce extruder wear through provision of separate, complemental, interfitted frustoconical screw and barrel sections adjacent the outlet end of the extruder barrel which create an even, bearing-type support for the rotating screws as material passes through the apparatus. In preferred forms, the screws are intermeshed along the majority of the extruder barrel, but diverge at the region of the final frustoconical screw sections and are received within respective complemental barrel sections; in this fashion the material being processed is split into juxtaposed, non-communicating streams, and thereby evenly flows around and supports the adjacent screw section to lessen the tendency of the screws to separate themselves and come into wearing contact with the surrounding barrel walls. The extruder can be used to process a wide variety of plant-derived materials, but is particularly useful for viscous substances (e.g.

Abstract: A twin screw extruder which significantly reduces extruder wear through provision of separate, complemental, interfitted frustoconical screw and barrel sections adjacent the outlet end of the extruder barrel which create an even, bearing-type support for the rotating screws as material passes through the apparatus. In preferred forms, the screws are intermeshed along the majority of the extruder barrel, but diverge at the region of the final frustoconical screw sections and are received within respective complemental barrel sections; in this fashion the material being processed is split into juxtaposed, non-communicating streams, and thereby evenly flows around and supports the adjacent screw section to lessen the tendency of the screws to separate themselves and come into wearing contact with the surrounding barrel walls. The extruder can be used to process a wide variety of plant-derived materials, but is particularly useful for viscous substances (e.g.

Abstract: A conditioning device for an extruder includes two juxtaposed, frustocylindrical, intercommunicated chambers, one chamber of which has a greater cross sectional area than the other chamber. A mixing shaft centrally located within the small chamber carries a number of radially extending beaters which rotate at a speed twice that of the rotational speed of paddles mounted on a second mixing shaft located in the large chamber and material introduced into the vessel is passed from side-to-side between the two chambers while being advanced along the length of the vessel. The use of relatively fast moving beaters within a small mixing chamber in combination with relatively slow moving paddles in a larger mixing chamber enables flour-like materials to be properly blended with water with both sufficient agitation and proper retention times within the vessel.

Abstract: An improved, low cost, energy efficient extrusion device and method for processing of cellulose, hemicellulose, and like fiber-bearing materials is described which includes a pretreatment extrusion zone and a reaction extrusion zone separated by a pressure sensitive variable die. The method hereof includes the steps of extruding cellulosic material through the pretreatment zone at an elevated pressure and temperature, passing the material into the reaction zone where it is mixed with an acid and is processed at a lower pressure and temperature than in the pretreatment zone, and extruding the material through a final extrusion die. The surging and blowing usually experienced with extrusion of fibrous material is drastically reduced by the unique construction of the extruder die members. The cellulosic material may be hydrolyzed to simple sugars in accordance with the method and apparatus hereof with a minimum of acid degradation of the extrusion equipment.

Abstract: An improved, low cost, energy efficient extrusion device and method for processing of cellulose- or fiber-bearing materials (e.g., wood chips, crop residues, whole or ground soybeans) is described which includes a transition screw section designed to smooth out material flow through the extruder and allow creation of increased barrel pressure and temperature levels. The transition section includes first and second alternating flights, with the depth of the first flight being less than that of the second flight and preferably gradually increasing until it equals the second flight depth. The overall extruder apparatus also advantageously includes a single flighted inlet screw section and a double flighted compression screw section respectively disposed on opposite sides of the transition section; in addition, the extruder has a pressure responsive adjustable die so that the effective dimensions of the die opening can be varied during the extrusion operation.

Abstract: An improved extruder screw section and barrel assembly is provided which is especially designed for effective extrusion processing of whole or cracked grains or cellulosic materials which can subsequently be converted to alcohol. The overall assembly includes an elongated, tubular head section presenting on the interior thereof at least one relatively sharp cutting edge (preferably in the form of a spiral rib), along with an elongated, axially rotatable screw section disposed within the head section. The screw section is characterized by a series of separate, elongated, circumferentially spaced grooves generally along the length of the section which progressively decrease in depth from one side margin of the grooves to the other, in the direction of screw rotation; thus, the material being processed is, by virtue of screw rotation and the groove configuration, pushed radially outwardly against the cutting edge presented by the surrounding barrel section.

Abstract: A commercially feasible, high-output extrusion apparatus and method is provided for producing vegetable protein based meat analogue products characterized by discrete, untwisted, manually separable meat-like layers and at relatively high production rates. The method involves passing hot, moist, pretreated vegetable protein material through an extruder barrel and causing formation of a first choke of the material intermediate the ends of the barrel, subdivision of the material downstream of the first choke point in the presence of steam for thorough cooking and moisturizing of the material, rechoking of the subdivided material adjacent the extrusion end of the barrel, and extrusion of the material as a dense, layered meat analogue product.

Abstract: A commercially feasible, high-output extrusion apparatus and method is provided for producing vegetable protein based meat analogue products characterized by discrete, untwisted, manually separable meat-like layers and at relatively high production rates. The method involves passing hot, moist, pretreated vegetable protein material through an extruder barrel and causing formation of a first choke of the material intermediate the ends of the barrel, subdivision of the material downstream of the first choke point in the presence of steam for thorough cooking and moisturizing of the material, rechoking of the subdivided material adjacent the extrusion end of the barrel, and extrusion of the material as a dense, layered meat analogue product.