Abstract: A device for separating particles in a liquid in which a paper suspension to be cleaned and supplied to a chamber of revolution (1) rotating about an axis (2). Movable deviators (7, 8) precede the fixed outlets (9, 10) to intercept most of the through-put of the suspension in the region of the periphery of the chamber (1), then deviate it towards the longitudinal axis of rotation (2) so as to recover most of the kinetic energy of rotation. The outlets (7, 8, 9, 10) are situated at the opposite end to that of chamber (1) from the supply (5, 6) and are arranged at the periphery of this chamber (1). A diabolo-shaped central body of revolution (11) is arranged inside the chamber, along the longitudinal axis of rotation (2) for rotation about its axis and with a radial run-off (12) in the vicinity of its smallest cross-section connected to an axial outlet duct (13).

Abstract: Method and device for preparation and primary separation of paper pulp in which the initial disintegration is produced in a primary pulper 1 of known type, the contents of the pulper, after this separation is discharged directly and discontinuously into a large-sized vat where it is stirred by an agitator with longitudinal shaft equipped with spiral arms, and from there poured discontinuously into a separator.

Abstract: The aeration of dispersions, especially the aeration of fiber suspensions in a flotation apparatus 1, is performed with a ring injector 2 to which air is delivered through air feed ducts 11 in the mixing section 4. The annular gap forming in the ring injector 2 is thus aerated inside and out. The center core 7, which tapers in the direction of the greatest free cross section Q4 of the ring injector 2, is provided with a fin 56 which prevents the rotation of the dispersion.

Abstract: The invention relates to a primary pulper turbine for processing recycled paper, of the type having the general shape of an helix.This turbine is formed of a shaft (2) carrying at least two helical disks (3, 4) coaxial to the shaft (2) and having a small pitch. These disks extend over at most 360.degree. and are spaced from each other along the shaft (2) by a distance of at least 1.5 times the helical pitch of a disk. The turbine carries on its base a set of radially extending fins (6, 7, 8), each one of which is curved into a spiral starting from the shaft (2).Preferably, the slant of the helical disks (3, 4, 5) relative to a plane perpendicular to the shaft (2) is approximately 15.degree., and the disks are angularly spaced from each other by a same angle approximately equal to 360.degree. divided by the number of disks, for providing a proper dynamic balance of the turbine.

Abstract: The invention relates to a method and apparatus for sorting out recycled paper pulp obtained from scrap material containing contaminants in the form of large pieces of foreign material such as plastics, adhesives, pieces of rope and the like.The invention avoids the need to disintegrate such large pieces of foreign material prior to their removal.The device of the invention comprises a drum (1) with an horizontal axis (2), an end wall (3) of the drum being fitted with a perforated plate (4) and an helical stirrer (5) having profiled blades rotating in a plane parallel to this plate at a short distance thereof, these blades having a transverse cross-section with a hydrodynamic profile adapted for generating a depression in front of the perforated plate, and a leading edge (6) forming a Bernouilli spiral with a constant angle of approximately 30.degree.

Abstract: A device for cleaning and recovering paper pulp includes a tank divided into inner and outer chambers by a fixed cylindrical sieve. The inner chamber also contains a rotating drum with blades that draw acceptable pulp from the outer chamber through the sieve to the inner chamber for discharge and moves rejected material through a helical path in the outer chamber toward another discharge point. The end of the helical path is blocked to form a dead space where the rejected material is concentrated and then periodically discharged.

Abstract: A process is provided for the removal from paper pulp of impurities, the pulp being contained in a pulping machine. Some of the pulp is periodically transferred into an enclosed chamber annexed to the pulping machine, the chamber having a volume which is small compared to the volume of the pulping machine. The pulp in the chamber is stirred and separated by a rotor, and fibre suspension is returned to the pulping machine, dilution water being introduced into this chamber. The chamber is emptied and impurities thereafter discharged.

Abstract: A process is provided for the removal from paper pulp of impurities, the pulp being contained in a pulping machine. Some of the pulp is periodically transferred into an enclosed chamber annexed to the pulping machine, the chamber having a volume which is small compared to the volume of the pulping machine. The pulp in the chamber is stirred and separated by a rotor, and fibre suspension is returned to the pulping machine, dilution water being introduced into this chamber. The chamber is emptied and impurities thereafter discharged.

Abstract: An apparatus for purifying paper pulp in the liquid state by screening. The apparatus comprising a cylindrical fixed screen disposed coaxially with a rotor within a housing. The rotor has longitudinal blades which, in section transverse to the rotor axis, have the general shape of an angle one side of the angle being substantially radial to the rotor and a second side inclined thereto. This apparatus is capable of both centripetal and centrifugal operation, and at concentrations of from 3 to 4%.