METHOD OF CONTINUOUS DYNAMIC FILTRATION AND AN APPARATUS FOR CARRYING OUT THE SAME

1,176,860. Filtration apparatus. VYZKUMNY USTAV ORGANICKYCH SYNTHES. 20 Dec., 1967 [21 Dec., 1966], No. 57857/67. Heading B1D. In a filter as illustrated in Fig. 1 (not shown), comprising a cylindrical housing (6), containing fixed hollow filter elements (7) and other filter elements (5) mounted on a rotary shaft (4), to which suspension is fed at one end (2) and from which thickened suspension is withdrawn through a valve or pump (15) at the other end, the torque applied to shaft (4) is monitored and compared with a preset level, and the difference is used to control valve or pump (15) to maintain the solids content of suspension in the housing around a fixed level. The valve or pump (15) may be electrically, hydraulically or pneumatically powered and may operate continuously at a variable rate or may be switched on or off as the difference reaches respective positive and negative predetermined values. Shaft (4) is turned by an electric motor, and torque may be measured directly, in terms of current or power consumption thereof, or indirectly with a dynamometer. The relative movement of elements (5, 7) creates agitation therebetween and prevents solids accumulating on their filtering surfaces. Either elements (5) or elements (7) could be replaced by non- filtering members. Elements (7) have individual filtrate outlets (8) and filtrate from elements (5) is discharged through hollow shaft (4).