Kamyr Ab

Kamyr Aktiebolag

Rune Hillstrom

Rolf Ekholm

Joseph R Phillips

Finn Jacobsen

Bjorn Ahs

Daniel Palsson

An apparatus for dewatering a pulp is described, comprising a vessel having a pulp chamber for pulp to be dewatered; a pulp inlet to the vessle; pulp outlet from the vessel; a filtrate chamber with an outlet for filtrate expelled from the pulp; a stationary cylindrical screen mounted within the vessel and defining said plup chamber and filtrate chamber on opposite sides thereof; and mechanical cleaning means supported by a shaft and disposed in the pulp chamber close to the screen face of the screen for removing a mat of pulp therefrom. The apparatus further comprises a backflushing means mounted outside the vessel and including a cylinder with first and second end portions and a piston mounted within the cylinder for reciprocal movement therein. The first end portion communicates with the interior of the apparatus, and the second end portion communicates with the filtrate chamber. Furthermore, the backflushing means comprises a power transmitting means for actuating the piston in the cylinder to move reciprocally in cycles each cycle comprising a slow stroke for drawing filtrate slowly into the cylinder and removing pulp slowly therefrom, and a fast stroke for expelling said drawn-in filtrate quickly out from the cylinder and drawing pulp quickly into the cylinder, said quickly expelled filtrate causing a backlfush through the screen.

Apparatus for dewatering pulp

A suspension of fibrous cellulose pulp is separated into at least two portions in an apparatus comprising a closed housing having inlet and outlets, and a rotor means provided with projections, said rotor means comprising a first rotor part surrounded by a screening means, the first rotor part and the screening means in their axial extension forming a screening zone and being arranged to cooperate with each other during rotation of the first rotor part for screening the suspension in a fluidized state. The rotor means comprises a second rotor part located immediately adjacent to the first rotor part, a rigid, water-impervious wall member surrounding the second rotor part. The second rotor part and the wall member form in their axial extension a pre-treating zone located immediately upstream of the screening zone and cooperate with each other during rotation of the second rotor part, Futhermore, the second rotor part has projections which, during rotation of the rotor part, run along the inner cylindrical surface of the wall member, without coming into contact therewith, so that the suspension is pre-treated and converted into a fluidized state suitable for screening in the screening zone located immediately thereafter.

Apparatus for separating a suspension of fibrous cellulose pulp

An apparatus for screening a suspension of fibrous cellulose pulp is described which comprises a housing and a rotor shaft, the housing having an inject section, first and second screening sections, each of which comprising rotor members mounted on the rotor shaft and a cylindrical screening plate cooperating therewith and defining an outer accept chamber and an inner screening chamber, and a reject section for the removal of fiber suspension remaining at screening, the inject section communicating with the screening chamber of the first screening section. According to the invention the inject section is disposed between the first screening section and the second screening section, and the screening chamber of the first screening section communicates with the adjacent reject section. The housing includes an inlet section disposed at the end of the second screening section facing away from the inject section, so that an internal space of the inlet section communicates with the screening chamber of the second screening section, whereas the accept chamber of the first screening section communicates with the internal space of the inlet section via a communication extending outside the housing for transferring the fiber suspension screened off in the first screening section to the second screening section. Further, the screening chamber of the second screening section communicates with the adjacent inject section for circulation of the remaining fiber suspension passing axially through the screening chamber, the accept chamber of the second screening section having an outlet for discharging fiber suspension which has been screened off.

Apparatus for screening a suspension of fibrous cellulose pulp

A method of delignification of cellulosic fiber material is described. The pulp containing said cellulosic fiber material is fed in a main line containing a main reactor in which the pulp is treated with oxygen. The pulp is screened at at lest one point in the main line, and the screen reject obtained is fed in a branch line containing at least one secondary reactor for separate treatment with oxygen. According to the invention the separate treatment with oxygen is carried out without previous refining, and the screen reject thus separately treated in said branch line is returned to the main line at a point upstream of said main reactor.

Growing community of inventors

Karlstad, Sweden

Rune Hillstrom