Compression rings for column relief in continuous cooking vessels
AssigneeAndritz-Ahlstrom Inc.
InventorJay K. Sheerer
Life of this patent
Estimating the term…
Abstract
The flow of a liquid slurry of comminuted cellulosic fibrous material (e.g. wood chips) in a vertical vessel is made more uniform by providing a plurality of vertically spaced sets of either substantially continuous or discontinuous protrusions which extend inwardly from the internal surface of the vessel a maximum distance of between about 2-12 inches. A preferred vessel is a continuous or batch digester. The protrusions may have an arcuate, rectangular, isosceles or scalene triangular, right triangular, or trapezoidal cross-section, and may be spaced from each other vertically between about 1-12 feet, and have a height of between about 1-3 feet. Discontinuous protrusions have a preferred arcuate spacing of between 1-10 feet.
Claims11
A method of treating a liquid slurry of comminuted cellulosic fibrous material in a substantially vertical vessel having an internal surface, comprising:
- (a) introducing the slurry into the vessel so that the slurry moves substantially downwardly in the vessel in a column;
- and
- (b) at a plurality of vertically spaced locations in the vessel temporarily relieving compressive forces on the comminuted cellulosic fibrous material within the column and the normal forces on the internal surface of the vessel so that friction between the comminuted material and the vessel internal surface is temporarily decreased, or substantially eliminated, providing more uniform flow of the material in the vessel.
Dependencies are inferred from the claim text.