SE9901220L - Input of finely divided fibrous material into a pulp cooking process - Google Patents

Abstract

In a chisel-type convergence for a chip bin in a wood chip pulping process and system (or other bin or hopper), an improvement in uniformity of discharge of the chips from a chips bin or the like is provided, including a substantially uniform flow velocity distribution along the slot outlet of the bin or hopper. The bin may include a conventional hollow substantially right circular cylindrical first, upper, body portion, a second, hollow transition, portion connected to the bottom of the first portion, and a third transition portion, below the second portion and above a metering device, such as a metering screw or a star-feeder. The third transition operates less than full of chips, and provides relief from chip compaction. The third transition portion may include stationary or movable baffles, and/or a metering screw may be provided which can pivot downwardly in order to minimize or eliminate the thrusting force against the bin or upper chips to facilitate discharge. Broadly a bin or hopper (preferably with one dimensional convergence and a slot outlet) is provided that has a metering screw substantially directly undeneath the slot outlet, and has a varying average pitch, shaft diameter, and flight diameter over the length thereof.