초록 ▼

A method and apparatus for separating particles from liquids is disclosed. The apparatus comprises a generally cylindrical swirl chamber with a generally axially symmetric shape, and a porous filter element positioned coaxially inside the swirl chamber. The porous filter is preferably composed of a

A method and apparatus for separating particles from liquids is disclosed. The apparatus comprises a generally cylindrical swirl chamber with a generally axially symmetric shape, and a porous filter element positioned coaxially inside the swirl chamber. The porous filter is preferably composed of a plurality of porous tubes. The liquid to be treated is forced into the swirl chamber through tangential injection slits extending along most of the height of the chamber, which generate a vortex flow inside the swirl chamber and around the porous filter element. Particle-free liquid permeates across the porous filter, flows along its interior, and is collected at a filtrate outlet port. The remaining liquid, now having a higher particle concentration, flows out of the apparatus and can be separately collected, or recirculated back to the apparatus for further separation. The swirling flow retards particle motion toward the filter element thus minimizing buildup of a cake of particles on the porous filter medium. The swirling flow also enables increased shear along the filter medium, reducing cake formation. In addition, the swirl produces a favorable stratification in the cake that tends to reduce the cohesion of the cake. The slits are designed to enforce similar flow conditions in all sections of the swirl chamber, thereby preventing uneven loading of the filter element and particle accumulation at the bottom of the chamber. The flow is periodically interrupted, causing the cake to be partially removed. These mechanisms enable attainment of much higher flow rates of effluent liquid than conventional cross flow filtration systems.

대표청구항 ▼

A method for separating particles from a liquid in a device with a longitudinal central axis including an outer fluid containment member with static members within, the outer fluid containment member encompassing an inner swirl chamber with a lateral wall that is substantially cylindrical in shape,

A method for separating particles from a liquid in a device with a longitudinal central axis including an outer fluid containment member with static members within, the outer fluid containment member encompassing an inner swirl chamber with a lateral wall that is substantially cylindrical in shape, at least one elongated porous filter element symmetrically positioned with respect to the central axis, multiple elongated narrow injection slits through the lateral wall, the slits are openings that are substantially coextensive with the at least one elongated porous filter element; the method comprising the steps of: (a) swirling the liquid about the longitudinal central axis by injecting the liquid through the elongated narrow injection slits, thereby generating a vortex with similar flow characteristics at various cross-sections of the central axis; (b) collecting filtered liquid at a first outlet from the device which permeates across the at least one filter element; and (c) collecting a mixture of particles and liquid which does not permeate across the at least one filter element at a second outlet from the device.