A device for separating the constituents of a fluid medium includes an element for separating the constituents, helping to define, upstream and/or downstream from the separation element, a closed chamber, to which at least one conduit is connected. The conduit includes at least one activatable sealing device, the activation of which is capable of at least partially closing and opening the conduit. The device also includes a controller for the activation of the sealing device, controlling the closing and opening, at least partially, of the conduit cyclically, at a frequency greater than 0.008 Hz.

A device for separating the constituents of a fluid medium includes an element for separating the constituents, helping to define, upstream and/or downstream from the separation element, a closed chamber, to which at least one conduit is connected. The conduit includes at least one activatable sealing device, the activation of which is capable of at least partially closing and opening the conduit. The device also includes a controller for the activation of the sealing device, controlling the closing and opening, at least partially, of the conduit cyclically, at a frequency greater than 0.008 Hz.

A screen sorting device for cleaning a fibrous stock suspension includes: an inlet for the fibrous stock suspension; a first sorting stage, which includes a first accepts discharge; at least one second sorting stage, which includes a second accepts discharge; and a fill level detection way, which is configured for detecting an accumulation height in the at least one second sorting stage and is assigned to the at least one second sorting stage.

An apparatus and a method for processing recycled material, comprising a first pulper (3) having an inlet (2) for receiving recycled material (1), a water inlet (26) for producing a mixture of water and particles of recycled material, a first rotor unit (R1) configured to slush recycled material and a first screen plate (18) connected to a first outlet (20) configured to extract a first portion of recycled material from the first pulper (3); a last pulper (8) having a reject washer configured to remove coarse rejected recycled material from the last pulper (8); and an upper channel (4) from the first pulper (3) to the last pulper (8), wherein the mixture of water and particles of recycled material is configured to flow over from the first pulper (3) to the last pulper (8). The apparatus comprises a of the last pulper (8) being lower than or at the same level as the first pulper (3); a lower channel (40) at the bottom of the first pulper (3) extending to the last pulper (8); and a gate (45) at the lower channel (40), configured to cause, when open, the mixture of water and particles of recycled material to flush to the last pulper (8).

An apparatus and a method for processing recycled material, comprising a first pulper (3) having an inlet (2) for receiving recycled material (1), a water inlet (26) for producing a mixture of water and particles of recycled material, a first rotor unit (R1) configured to slush recycled material and a first screen plate (18) connected to a first outlet (20) configured to extract a first portion of recycled material from the first pulper (3); a last pulper (8) having a reject washer configured to remove coarse rejected recycled material from the last pulper (8); and an upper channel (4) from the first pulper (3) to the last pulper (8), wherein the mixture of water and particles of recycled material is configured to flow over from the first pulper (3) to the last pulper (8). The apparatus comprises a of the last pulper (8) being lower than or at the same level as the first pulper (3); a lower channel (40) at the bottom of the first pulper (3) extending to the last pulper (8); and a gate (45) at the lower channel (40), configured to cause, when open, the mixture of water and particles of recycled material to flush to the last pulper (8).

A pulper for circulating a fibrous stock suspension. The pulper includes at least one screen, having a screen surface which is provided with screen openings, and over which a rotor passes. The rotor is formed by a rotor head, to which a plurality of rotor blades are attached on the outer circumference. The rotor circle of the screen, which is passed over by the rotor wings, includes a plurality of bar-shaped elevations. In the process, pulping is to be improved, while wear is to be minimized, in that the angle of intersection between the working edge of the rotor blades pointing in the direction of rotation and the shear edge of the elevations pointing counter to the direction of rotation does not decrease radially outwardly.

A pulper for circulating a fibrous stock suspension. The pulper includes at least one screen, having a screen surface which is provided with screen openings, and over which a rotor passes. The rotor is formed by a rotor head, to which a plurality of rotor blades are attached on the outer circumference. The rotor circle of the screen, which is passed over by the rotor wings, includes a plurality of bar-shaped elevations. In the process, pulping is to be improved, while wear is to be minimized, in that the angle of intersection between the working edge of the rotor blades pointing in the direction of rotation and the shear edge of the elevations pointing counter to the direction of rotation does not decrease radially outwardly.

A cellulose nanofibrils production method comprising the steps of: identifying a desired level of cellulose nanofibrils pulp purity, partially refining pulp to produce a cellulose nanofibrils pulp purity between 5% and 15% less than the desired desired purity, and then separating out the cellulose nanofibrils from the longer fibers to produce the desired level of cellulose nanofibrils pulp purity.

A cellulose nanofibrils production method comprising the steps of: identifying a desired level of cellulose nanofibrils pulp purity, partially refining pulp to produce a cellulose nanofibrils pulp purity between 5% and 15% less than the desired desired purity, and then separating out the cellulose nanofibrils from the longer fibers to produce the desired level of cellulose nanofibrils pulp purity.

A rotor unit in a vessel containing a mixture of water and particles of recycled material, comprising a rotor unit body (19); a screen plate (18) installed to the vessel; a rotor (78) connected to the rotor unit body (19) and configured to rotate inside the vessel, comprising at least two wings (81) configured to slush recycled material in a rotating action and at least two foils (82) configured to clean the screen plate (18) by rotating above the screen plate (18); a space (89) around the rotor (78) defined by a rotor body (77); pipework (21) configured to bring diluting water from outside the vessel to the space (89) around the rotor (78); wherein the rotor body (77) defining the space (89) around the rotor (78) comprises an opening (76) allowing the diluting water to pass through the opening (76) towards the mixture of water and particles of recycled material. The opening (76) at the rotor body (77) is at the same level with the lower edge of the at least two wings (81) or the at least two foils (82), wherein the diluting water is allowed to pass through the opening (76) to the screen plate (18).