GB1205947A - Process and apparatus for recovery of sucrose - Google Patents

Abstract

1,205,947. Extrusion press filter. FRENCH OIL MILL MACHINERY CO. 26 Sept., 1967 [18 Oct., 1966], No. 43867/67. Heading B1D. [Also in Division C6] In the extraction of sugar or a similar process involving the removal of liquid from fibrous materials, bagasse resulting from a first extraction by a diffusion system is fed by a rotating feed worm 42 in a hopper 40 to a series of more slowly rotating expressing worms 48 of progressively reducing diameters disposed in axial alignment along the length of a barrel which is divided into two or more (three, as shown) sections 45, 65, 75 of correspondingly reducing diameters, a ring member or members 60, 70, having a tapered inner surface, being fitted between adjacent sections, the expressing worms including a corresponding tapered section of worm flight 68 co-operating with the or each ring member, there also being a discharge ring 96 defining an inwardly tapering press outlet at the outlet end of the final barrel section, a discharge sleeve 90 having a tapered outer surface mounted for axial movement between inner and outer positions corresponding to minimum and maximum areas respectively of the annular outlet thus formed, and means yieldably urging the discharge sleeve towards its inner position so as to regulate the pressure in the bagasse and maintain this pressure at a predetermined value. The tapering inner surface of the discharge ring is extended inwardly by a bush 92 whose inner surface first tapers inwardly and then outwardly. A main drive shaft 50 passes through the various worms and terminates in a threaded end which carries a nut 80 on which the sleeve 90 is slidably mounted with the interposition of a bush 82. The expressing worms, comprising a succession of body members 48a having flight members 48b and separated by spacers 49, are secured directly to the shaft 50, while feed worm 42 is driven at a higher speed via gearing (not shown). The walls of the barrel sections 45, 65, 75 are provided with outlet openings (52, Fig. 4, not shown) for the extracted juice and also with breaker bars 47 projecting inwardly into the spaces between the flight members 48b, the bars 47 preferably being slotted. Movement of sleeve 90 is resisted by a hydraulic cylinder 103 through rod 100, the hydraulic pressure in cylinders 103 being controlled by a pressure-regulating valve (188, Fig. 5 not shown), hydraulic fluid being supplied by a pneumatically operated booster pump (155). Motor overload switches (202, 204) control a solenoid-operated valve (195) to release pressure should the resistance to rotation of the worms become inadmissably high.