Improvements in scrapers or sweep devices for removing sediment or sludge from settling tanks or reservoirs

摘要

619,345. Scraping apparatus. FARRER, Ltd., W. E., and FARRER, W. G. Dec. 3, 1946; No. 35830. [Class 68 (i)] [Also in Group XXIII] The sludge from the bottoms of tanks is removed whilst the tanks are full by an apparatus 2 consisting of a structure having an inverted V- or U-shaped cross-section, the inclined depending limbs 6 carrying scraper blades 7 that cut into the sludge when the apparatus is dragged forward by a power - operated carriage moving over rails placed above and at either side of the tank. The upper portion of the apparatus is sealed off to form a buoyant chamber 9 and the towing cables 3 are attached at either end at a point 17 below this chamber so that the apparatus does not overturn on being dragged forward. The apparatus may be mounted on wheels, the scraper blade being carried centrally of the wheels. If the apparatus is intended to cut in one direction only, then only one blade is provided, a counterweight being placed on the other limb. Vent holes 15 are formed below the buoyant chamber, which may be replaced by a block of buoyant material, to prevent air being trapped with the structure and upsetting the balance. In the case of a circular tank, the towing carriage travels along an arm rotating about the centre of the tank. The apparatus may be used to remove scum from the surface of the tank contents.