Abstract: A device for treating a preferably cellulose containing suspension, comprising a housing (110) on a stand (112), characterized in that it comprises an injection chamber (132) limited by two disc-shaped wall members (134) arranged so as to rotate about a center of rotation (C') common to the axle, in that at least one inlet opening (130) is disposed in the inner part of the chamber (132) for the suspension to be treated, in that outlets (167) for the treated suspension are disposed in an outer part (166) (the acceptance space) of the injection chamber (132), in that extraction chambers (170) are disposed outside the wall members (134) of the injection chamber (132), in that openings (164) for filtrate are disposed between the injection chamber (132) and the extraction chamber (170) within at least one annular zone of the radial extent of the wall members (134), in that outlets (130) for filtrate are arranged from the extraction chambers, and in that the size of the injection chamber is variable.

Abstract: The invention relates to a method for lime sludge reburning in a fluidizing bed. The method is characterized in that a cooling medium (10) is injected immediately above the fluidizing bed (3). The invention also comprises means for performing the method. The arrangement which is known per se is provided with an injection device (10) for a cooling medium above the fluidizing bed (3).

Abstract: The present invention relates to a fluid reservoir, chiefly a reservoir whose purpose is to constitute a buffer, wherein the liquid level varies substantially comprising an inlet conduit (1) for liquid, an outlet conduit (2) for liquid, reservoir walls (3), a reservoir bottom (4) and a liquid outflow arrangement (5) located inside the said reservoir, which is connected to the said inlet conduit (2), the said outflow arrangement (5) comprising means (6) to ensure that its opening (7) follows the surface of the liquid (8) in the said reservoir (3, 4), the opening (7) preferably being located so that it discharges on a level with or immediately below the said liquid surface, which significantly reduces the risk that gas is included in the liquid flowing out via the outlet conduit.

Abstract: The invention relates to a pump for pumping fibrous pulp suspension and separating gas from the suspension, comprising a pump casing with a pump casing chamber (4) with an axial inlet (17) and a radial outlet (6) for the suspension and also a gas outlet (19); in the pump chamber part a pump wheel (3) with a hub (27), on the hub front pump vanes (30) in a front pump chamber part (4A) facing the inlet, rear pump vanes (32) in a rear pump chamber part (4B) and an annular partition (28) between the front and rear pump chamber parts, which partition is joined to the hub; and a drive shaft (10) for the pump wheel which extends through one end wall (7) of the pump casing, and also bearing members (13, 14, 15) for the drive shaft.

Abstract: The invention relates to a process for dividing up the sulphide content of green liquor into a sulphide-rich part and a sulphide-poor part by crystallizing out sodium carbonate (Na.sub.2 CO.sub.3). The crystallization of the sodium carbonate is effected by evaporating green liquor with a ratio of hydroxide ions [OH.sup.- ] and sulphide ions [HS.sup.- ] such that the liquor which is obtained after evaporation and separation of the solid phase has high sulphidity and an acceptably low content of carbonate ions [CO.sub.3.sup.2- ]. Prior to evaporation, the hydroxide ion content in the liquor is increased by adding quicklime (CaO). The solid phase (sodium carbonate and calcium carbonate) which has been separated off is diluted with water so that the sodium carbonate crystals go into solution and at the same time the solution is given a cation content which favours the causticization which is subsequently undertaken. The causticization is carried out in a conventional causticization plant.

Abstract: In a pulp digester for continuous cooking under raised pressure and temperature of fiber material in a vertical digester (1), input of fiber material and cooking liquid takes place at the top of the digester, withdrawal of spent cooking liquor is carried out from at least one digester screening arrangement (1D) between the top and the bottom of the digester, and fiber material is fed out from the bottom (1C) of the digester, and at least one screening arrangement (2) in the lower half of the digester, wherein at least one of said screening arrangements (1, 2) has at least one screen element (2A) of which the main configuration is of angular shape, preferably rectangular, most preferred square, having a screen face (3A) of which the total area is less than 1 m.sup.

Abstract: A process for chlorine-free bleaching of chemical pulp in association with the production thereof, where a suspension of the pulp preferably has a concentration exceeding 8% of cellulose-containing fiber material and where the pulp entering into a bleaching line is preferably fed continuously through at least one bleaching vessel in the bleaching line, is treated with at least one acid for adjusting the pH to a value below 7, and with a chelating agent, and is subsequently bleached in at least one stage to a brightness exceeding 75% ISO, preferably exceeding 80%, with hydrogen peroxide or the corresponding quantity of another peroxide, employed in a quantity exceeding 5 kg/BDMT, where the peroxide bleaching takes place at elevated temperature and at a pressure in the bleaching vessel which exceeds 2 bar and where the cross-sectional area of the bleaching vessel exceeds 3 m.sup.2 and the area of the metal surface exposed towards the interior of the bleaching vessel is less than 4 V m.sup.

Abstract: The invention relates to a diffuser, comprising a substantially cylindrical, vertical container, through which cellulose pulp is arranged to be transported, nozzle arms, for delivering a fluid, such as washing liquid, to the pulp, concentrically disposed screen surfaces and screen arms disposed on and connected to said screen surfaces for withdrawal of said fluid. The screen arms are provided, at their outer ends, with withdrawal pipes, directed substantially vertically downwards, which are slidably controlled and are connected in sealing arrangement to outlets for said fluid. The invention relates also to a stuffing box designed to receive a rod, preferably a pull rod for raising and lowering a screen pack having screen surfaces in a diffuser, said rod being guided in sealing arrangement and slidably through a fixture which is mounted in a bearing for free movement in a plane substantially perpendicular to said rod.

Abstract: An apparatus for mixing a first fluid into a second fluid that comprises a housing (1) having a flow chamber (39) for the second fluid, a flow restrictor member (6) in the flow chamber, and holes (18) for introducing the first fluid into at least one gap (15, 16) between the flow restrictor member and those walls (5, 10) of the flow chamber (39) facing towards the flow restrictor member. The flow restrictor member and flow chamber, in a plane transversely to the principal flow direction (31) of the second fluid, each has the shape of a wedge. Gaps (15, 16) are formed between each of those two sides of the flow restrictor member that converge in a wedge shape and those walls of the wedge-shaped chamber facing towards the flow restrictor member. The holes (18) for introducing the first fluid are disposed in the region of the gaps (15, 16).

Abstract: A method for washing a fibre suspension including the steps of feeding the suspension into an annular displacement space, supplying a fluid through a permeable outer surface of the space, rotating the space to establish a fibre layer between the fluid supplied through the permeable outer surface of the displacement space and a remaining part of the fibre suspension.

Abstract: A screening device for pulp production includes a cylindrical container for continuous flow-through of a fiber suspension and further includes an inlet to the container and an outlet for the fiber suspension, a moveable support member mounted in the container and which supports hollow screening members for vertical movement; a tubular enclosure open at opposite ends is mounted on the supporting member which enclosure has a moveable piston mounted therein, a hydraulic cylinder being connected to the piston to move the piston in a portion of the enclosure with the hydraulic drive mounted outside of said container with transmission members connected to said supporting member which will therefore absorb the reaction forces generated in moving the piston.

Abstract: A method of integrating bleaching and recovery in connection with the production of chemical pulp that has been digested and preferably delignified with oxygen gas using processes that retain the viscosity and strength, to kappa number less than 16 without the use of chemicals containing chlorine, and using a bleaching sequence including at least one step with sequestering agent and/or acid, and a peroxide step.

Abstract: A process for the continuous digestion of cellulosic fiber material, comprising impregnation with impregnating liquid consisting of at least one fresh digesting liquor, in a closed impregnating system and subsequent digestion with digesting liquid in a closed digester system, said impregnating liquid being supplied through a supply system, together with steamed fibre material, to an inlet end of the impregnating system, liquid being withdrawn from the impregnating system at a point (46) located at a predetermined distance from said inlet end.

Abstract: A process for recovering energy from a combustible gas generated by partial oxidation of cellulose waste liquor in a gas generator (A) operating in a temperature range of 600.degree.-1300.degree. C. and a pressure in the range of 1-100 bar, cooling and cleaning said combustible gas and using the gas as fuel in a recuperated gas turbine cycle (C, E), wherein water and/or steam is injected to humidify compressed air and/or combustible gas, increasing turbine motive fluid massflow and power output.

Abstract: A screening body for a pulp digester includes two, spaced apart ring supporting a plurality of axially extending screening bars each of which has a foot portion frictionally received in and welded to a correspondingly formed recess formed on the inner side of each of the ring segments; an apparatus for manufacturing a screening body is also provided and which includes a first assembly member which mounts a form for receiving the ring member segments in parallel relation and into which are inserted the screening bars with the foot portions fractionally received in complementary recesses formed on the inner side of each of the ring segments; a retaining member in the form of a second assembly device includes a cylindrical drum surface which is pressed against the screening bars of a partially assembled screening body section while a second and subsequent sections of the screening body are assembled.

Abstract: A screening body for a pulp digester includes two, spaced apart ring supporting a plurality of axially extending screening bars each of which has a foot portion frictionally received in and welded to a correspondingly formed recess formed on the inner side of each of the ring segments; an apparatus for manufacturing a screening body is also provided and which includes a first assembly member which mounts a form for receiving the ring member segments in parallel relation and into which are inserted the screening bars with the foot portions fractionally received in complementary recesses formed on the inner side of each of the ring segments; a retaining member in the form of a second assembly device includes a cylindrical drum surface which is pressed against the screening bars of a partially assembled screening body section while a second and subsequent sections of the screening body are assembled.

Abstract: A screen dram for the dewatering and/or washing of cellulose pulp, comprises a first cylinder (2) made from non-stainless material, which is rotatable about its axis (5); a cylindrical screen plate (6) arranged coaxially on the outside of the first cylinder, but at a distance from it, and between the screen plate and the first cylinder an annular chamber (7) which can receive liquid which has passed through the screen plate, which chamber contains passages (26) which extend in the axial direction towards one or both ends of the drum for the withdrawal of the screen liquid. The chamber (7) is lined with stainless steel (8) in the form of one or more cylindrical plate sections (8a, 8b . . . 8n). These, by virtue of shrink joints, can be joined to and bear in seal-tight arrangement against the cylindrical casing of the first cylinder. Preferably, the stainless steel contains at least 5% molybdenum.

Abstract: In a pulp digester for continuous cooking under raised pressure and temperature of fiber material in a vertical digester (1), input of fiber material and cooking liquid takes place at the top of the digester, withdrawal of spent cooking liquor is carried out from at least one digester screening arrangement (1D) between the top and the bottom of the digester, and fiber material is fed out from the bottom (1C) of the digester, and at least one screening arrangement (2) in the lower half of the digester, wherein at least one of said screening arrangements (1, 2) has at least one screen element (2A) of which the main configuration is of angular shape, preferably rectangular, most preferred square, having a screen face (3A) of which the total area is less than 1 m.sup.

Abstract: A device for treating a preferably cellulose-containing suspension, comprising a housing (1) on a stand (2).

Abstract: Apparatus for treating pulp with a treating liquid, comprising a vessel (1) with cylindrical wall (2), inner screening means (3) for withdrawing liquid from the pulp, and a plurality of distributing tubes (5) on the outside of the vessel for the supply of treating liquid into the vessel through a plurality of inlet connections (6). According to the invention each distributing tube (5) is formed of an annular section (20) and an opposing part (21) of the cylinder wall (2), the section being welded directly to the cylinder wall, and the section and the cylinder wall part enclosing between them a distributing channel (22). Furthermore, each inlet connection (6) is provided with an opening (23) extending through the cylinder wall part and connecting the distribution channel to the interior of the vessel.