Patent GB-339528-A (GB)
Title: Method and apparatus for producing fibrous material
IPC: B02C15/14
Filed: 1930-01-11
Abstract: 339,528. Clark, D'A. M., (Respats, Inc.). Jan. 11, 1930. Boards; pulp, preparation of; pulping- engines.-In the manufacture of fibrous material suitable for the preparation of paper, moulded sheets and blocks, from waste wood, fibrous plants, and the like, such as wood chips, pineapple waste, cocoa-nut fibre, palmetto fibre, flax straw, saw grass, and other ligneous and woody materials, the material, which may be first softened by cooking with caustic soda solution, is mixed with a loose, finely divided splitting agent such as sand or broken stone and the mixture kneaded in a mill comprising a track 5 lined with wear-resisting material 3 in which heavy bevel-edged kneading wheels 9, having wear resistant shoes, rotate. The wheels are mounted on an axle 20 slotted into a vertical shaft 22 driven by gears 29, 30 from a shaft 31. Scrapers 35 follow the rolls 9 and transfer the material from the bottom of - the track 5 to the side thereof. The removal of the kneaded material from the mill is effected by a scoop 37, Fig. 5, connected to a, grooved collar 80 on the shaft 22 and adapted to be raised out of operation by means of a swinging yoke 81, a link 82 and a locking ratchet 85. The scoop 37 transfers the material from the track 5 through the opening 7 within the track to any suitable receiving means such as a conveyer belt 40 which may be arranged to receive material from a number of mills. A removable plug 49 permits the washing of the mill when necessary. The major portion of the parenchymatous, substances present are thus retained in the mass. A small quantity of long fibres of jute, cocoanut. the cortex layers of flax plants, pineapple or palmetto leaves, hemp, coarse vegetable fibres such as sisal, bamboo reed, New Zealand flax, nettle, and ramie stalks may be added to the mixture before the end of the kneading operation. When chips have a high resinous content, the cooking and milling operations may be re- - peated. The mixture after kneading is transferred to a vat 50, Fig. 3, filled with water, where, under the action of air bubbles from jets 51, the splitting agent sinks to the bottom and the fibrous material rises and is picked up by a conveyer 54 and transferred to a machine resembling a Fourdrinier paper-machine for manufacture into sheets, or to other apparatus. The sand at the bottom is impelled out of the vat by a suitable water ejector and may be used repeatedly. Sheets &c. made from fibrous material so prepared retain a sufficient resinous gum content to act as a binding agent which is fused or vulcanized when the sheets are subjected to heat and pressure. Additional binding agents such as the resinous constituent reclaimed from the cooking liquor may be added, and also a suitable reagent such as aluminium sulphate to render the resinous constituents insoluble and thus produce a waterproof board. The sand may be allowed to remain in the disintegrated mass which, with the addition of cementitious material such as Portland cement or gypsum, may be moulded into sheet or block form and used for building or paving purposes.