Screening device
OwnerSten Eskil Einarsson Ahlforsinventor
Life of this patent
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Abstract
A treatment chamber for purification and fractionation of materials suspensions, particularly fibrous suspensions under pressure, and wherein the treatment chamber includes a rotary screening drum provided with pulsation members, the drum also including screening holes located on the back-side of, or immediately behind, the pulsation members as viewed in the direction of drum rotation.
Claims16
A device for purifying and fractionating a material suspension, notably a fiber suspension, under pressure, said device including
- a treatment chamber having a circular cross-section, with an inlet for the suspension and outlets for reject and accept, respectively;
- a screening drum having a circular cross-section and rotatable in the treatment chamber, said drum being provided with pulsation organs;
- said inlet being exterior of said drum,
- each pulsation organ having a limited extension along the axial dimension of said drum, and a rounded front surface, said organ being adapted to create pulsations in the suspension layer close to the screening drum,
- said drum being perforate to provide an array of screen holes spaced on the surface of said drum,
- the number of screen holes being considerably larger than the number of pulsation organs and
- at least one screen hole being located on the surface of each said pulsation organ at its leeward side, viewed in the direction of rotation of said drum, thereby causing a local return flow outwardly through said screening drum.
A device for purifying and fractionating a material suspension, notably a fiber suspension, under pressure, said device including
- a treatment chamber having a circular cross-section, with an inlet for the suspension and outlets for reject and accept, respectively;
- a screening drum having a circular cross-section and rotatable in the treatment chamber, said drum being provided with pulsation organs;
- said inlet being exterior of said drum,
- each pulsation organ having a limited extension along the axial dimension of said drum on its exterior surface, and a rounded front surface, said organ being adapted to create pulsations in the suspension layer close to the screening drum,
- said drum being perforate to provide an array of screen holes spaced on the surface of said drum,
- the number of screen holes being considerably larger than the number of pulsation organs and
- at least one screen hole being located on the drum surface adjacent to said pulsation organ on its leeward side viewed in the direction of rotation of said drum, thereby causing a local return flow outwardly through said screening drum.
Dependencies are inferred from the claim text.