Abstract: A biological wastewater treatment system includes an equalization tank for sending a defined first portion of the wastewater to a submerged membrane filter. When the quantity of the received wastewater exceeds the defined first portion, a second portion of wastewater, formed from the wastewater that exceeds the defined first portion, is sent to a filtration process. The filtration process includes adding a flocculating agent to the second portion entering filtration, filtering the second portion, thereby producing retentive waste including flocculated material, and then sending the retentive waste to the submerged membrane filter.

Abstract: An apparatus for mixing a first fluid into a flow path (44) of a second fluid, said apparatus having a chamber (12), which encloses the flow path and exhibits a first inlet (13) for receiving the second fluid, a second inlet (15) arranged downstream of the first inlet for receiving the first fluid, as well as an outlet arranged downstream of the second inlet for discharging a mixture of the first fluid and the second fluid, said flow path extending from the first inlet to the outlet and said second inlet opening into the flow path, a throttle body (29), which is pivotally arranged inside the chamber for controlling the flow area of the flow path, and pivoting means (50, 51) for pivoting the throttle body for said controlling of the flow area.

Abstract: A rotor adapted for mounting for rotation within a screen of a pulp screening apparatus, and for defining a screening space between the rotor and the screen so that pulp suspension flows into the screening space, with accepted pulp passing through the screen to a stock outlet and rejected pulp passing along a screen inlet surface in a screening flow direction to a rejects outlet. The rotor has an interior, and an exterior with pressure impulse protuberances thereon for rotation with the rotor in close proximity to the inlet surface. A stock inlet communicates with the screening space and the rotor interior. And the rotor has at least one opening extending in the screening flow direction from its interior to its exterior for over at least a fourth of screening flow length of the rotor for admitting a substantial portion of pulp suspension from the stock inlet and the rotor interior into the screening space.

Abstract: A hydrocyclone (1) for separating a liquid mixture into a heavy fraction including heavy particles and alight fraction, comprising a housing (2) forming an elongated separation chamber (3) having a circumferential wall (4), abase end (5), an apex end (6), at least one inlet member (7) for supplying a liquid mixture into the separation chamber (3), at least one of the inlet member/s (7) positioned at the base end (5), a first outlet member (8) for discharging separated light fraction from the separation chamber (3) at the base end (5), a second outlet member (9) for discharging separated heavy fraction from the separation chamber (3) at the apex end (6), means (10) for supplying the liquid mixture to the separation chamber (3) via the at least one inlet member (7), so that during operation a liquid stream is generated as a helical vortex (11) about a center axis (12) in the separation chamber (3), said helical vortex (11) extending from the base end (5) to the apex end (6), a first flow deflection means arrang

Abstract: A hydrocyclone (1) for separating a liquid mixture into a heavy fraction and a light fraction, comprising a housing (2) forming an elongated separation chamber (3) having a circumferential wall (4), a base end (5), an apex end (6), means (10) for supplying the liquid mixture to the separation chamber (3) via the at least one inlet member (7), so that during operation a liquid stream is generated as a helical vortex (11) about a centre axis (12), at least one path (13) in the circumferential wall (4) at least over a portion of the separation chamber (3), and at least one means for creating turbulence, which comprises at least one step (14) in the path (13) of the circumferential wall (4) showing an increase of the radius of the separation chamber (3), wherein the at least one step (14) having an angle (?) relative the centre axis (12).

Abstract: An impeller for use in association with an extraction plate adapted for defibering liquid slurry stock and causing defibered material to pass through the extraction plate. The impeller includes a cylindrical central body portion and a plurality of vanes extending outwardly in a generally tangential direction from the central body portion. The vane leading face height from an extraction side to an air foil surface is substantially constant from the vane outer end to where the vane is attached to the central body portion at the radially outward edge of the central body portion, and then thereafter gradually decreasing in height from the radially outward edge of the body central portion to the airfoil surface at the vane inner end.

Abstract: A device including a hollow cylindrical body, first and second stationary coaxial annular screening screens disposed within the body, and a rotor within the body and positioned between the screens to conduct the slurry through the first screen and then through the second screen, the rotor being driven in rotation. The pulp slurry passes through a central entry pipe, radially outward and then upward along the inside of the rotor, further inward through a coarse screen cylinder, and then around the end of the rotor to pass between the outer surface of the rotor and the inner surface of a fine screen cylinder. The pulp slurry then finally passes outward through the fine screen cylinder. Coarse rejects, such as knots or other coarse material, are collected at the end of the coarse screening chamber and led away for further processing. Fine rejects are similarly collected at the end of the fine screening chamber, also to be led away separately for further processing.