BELT PRESS-FILTER FOR SLIME AND SLUDGE DEWATERING Russian patent published in 2003 - IPC

FIELD: treatment of sewage waters for removal of slime and sludge accumulated in operation of industrial and public utility enterprises. SUBSTANCE: press-filter consists of carrying frame in which many shafts are mounted. Passed between shafts are two endless belt-type sieves of lower and upper locations. Shafts are rotated by electromechanical drive through driven and two driving shafts. Belt sieves are tensioned by two shafts located in movable bearings with separate hydraulic drives. Liquid slime is loaded onto upper sieve on which free filtration of slime liquid fraction takes place. At the end of zone, partially dewatered slime is transferred onto lower belt through trough. Further on, belt sieves are combined on shaft, and liquid slime is located between belts and enters zone of initial compaction formed by three shafts with symmetrical location coordinates. Initial compaction is characterized by low specific pressures which are built up, either by principle of one-sided squeezing by belt sieves of three shafts over tangent circular surface, or by two-sided squeezing of three-shafts by wave-like principle when belt sieves roll around the middle shaft from atop. In zone of initial compaction thinning of liquid slime occurs in conditions when liquid phase of slime is squeezed out and slime itself is not squeezed out of edge of combined belt sieves. Squeezing out of slime is prevented by two-sided flanging of shafts made in the form of conical bans. Similar shafts are installed in zone of wave compaction pressures in direction of slime dewatering progress. High specific pressure in compaction rise in zone where dewatering is ended and slime is thickened with its subsequent removal by scrapers. EFFECT: higher efficiency of liquid slime dewatering with reduced expenses for manufacture and use of press-filters. 2 cl, 3 dwg