Abstract: The invention is concerned with a process for transporting a thermally unstable viscous mass through pipes and is characterized in that(a) during transportation, the mass is divided into X.sub.1 partial flows T.sub.1, X.sub.1 being calculated according to the relationX.sub.1 =Q.sup.(N-1), (I)wherein Q and N indicate positive integers independent from each other, and(b) the viscous mass in the partial flows is transported at the same rate.

Abstract: The invention is concerned with a device for the continuous delivery of shredded materials exhibiting low flowability, particularly shredded cellulose materials, characterized in: (A) a receptacle for the shredded material to be delivered, said receptacle having an inlet and an outlet and whereto shredded material is delivered by means of an inlet screw, (B) a discharge arm provided in the receptacle and being arranged rotatably, which discharge arm transports the material present in the receptacle towards the outlet by means of rotation, (C) an outlet pit joined to the outlet receiving the material delivered to the outlet by the discharge arm, (D) an outlet screw protruding into the outlet pit and discharging the material delivered to the outlet pit (FIG. 1).

Abstract: To prepare cellulose fibres, a solution of cellulose in a tertiary amine-oxide is shaped in hot condition to give filaments, the filaments are cooled and then introduced into a precipitation bath in order to precipitate the dissolved cellulose, whereby the shaped solution is exposed to an essentially laminar gas stream (FIG. 2a) for cooling before introduction into the precipitation bath.

Abstract: The invention is concerned with a process for the production of a suspension of cellulose in a liquid, aqueous tertiary amine-oxide, wherein shredded cellulose is mixed with the liquid, aqueous tertiary amine-oxide, said process comprising:(A) contacting the shredded cellulose with the liquid, aqueous tertiary amine-oxide, a first mixture being prepared, and(B) spreading this first mixture mechanically as a layer on a surface and transporting it along this surface while intensively being mixed, until a homogeneous suspension is produced which is removed from the surface, wherein(C) measures (A) and (B) are carried out continuously.

Abstract: The spinneret according to the invention is especially suitable for spinning cellulose solutions and has a die body which is essentially rotationally symmetrical having an inlet in its centre for cooling gas, an inlet for cellulose solutions, an annular deep-drawn spinning insert of precious metal with spinning holes wherein the spinning insert is designed pan-shaped in cross-section, and a baffle plate to deflect the cooling gas stream through the cellulose filaments which are extruded from the spinning holes, so that the cooling gas stream strikes the extruded cellulose filaments essentially at right angles. The spinning holes in the spinning insert are uniformly spaced from one another.

Abstract: A process is disclosed for the preparation of a shapeable solution of cellulose in an aqueous tertiary amine-oxide from comminuted cellulose. The process includes introducing previously comminuted cellulose material into an aqueous solution of a tertiary amine-oxide to prepare an initial suspension, subjecting the initial suspension to high-consistency milling to further break-up the cellulose material to obtain a second suspension, and converting the second suspension into a shapeable solution of cellulose by heating under reduced pressure.

Abstract: Method for the preparation of cellulose sheet by extrusion of a heated solution of cellulose in a tertiary amine-oxide, which method includes using an extrusion die with an extrusion orifice, characterised in that, immediately below the extrusion orifice there is provided an inlet for cooling gas to cool the extruded sheet. The method according to the invention is especially suitable for the preparation of cellulose tubular films.

Abstract: A plant for the production of cellulose films and fibers includes at least one pulping device for producing a first suspension of pulp in an aqueous amine-oxide solution and a first thin-film treatment apparatus for receiving the first pulp suspension and producing a concentrated pulp suspension. The plant also includes a second thin-film treatment apparatus wherein the concentrated pulp suspension is transformed into a mouldable solution of cellulose and a spinning device connected to the second thin-film treatment apparatus, wherein the mouldable cellulose solution is processed into cellulose films and fibers. A process for the production of cellulose films and fibers according to an amine-oxide process includes the steps of suspending pulp in an aqueous amine-oxide solution to produce a first suspension, concentrating the first suspension, producing a mouldable cellulose solution by heating, and processing the solution to form cellulose films and fibers.

Abstract: To prepare cellulose mouldings, a solution of cellulose in a tertiary amine-oxide is moulded in a hot state and the moulded solution is introduced into a precipitation bath in order to precipitate the contained cellulose, wherein the hot moulded solution is cooled before introduction into the precipitation bath. Cooling occurs immediately after the moulding process and preferably consists of blowing air horizontally on to the cellulose moulding. The process according to the invention allows spinning of the cellulose solution with a high fibre density without the spun fibres sticking together after emerging from the spinneret. In spite of the high fibre density, it furthermore allows the use of a long air gap between the spinneret and the precipitation bath, by which means sufficient time is generated in the spinning process to affect the textile properties of the fibres by drawing at the die.

Abstract: The invention is concerned with a process for controlling a flowing suspension of shredded cellulose in a liquid, aqueous tertiary amine-oxide and is characterized by the combination of measures that (A) the suspension is introduced into a vessel having an inlet for the suspension, (B) the suspension introduced into the vessel is transported through the vessel and (C) the suspension transported throught the vessel is discharged from the vessel by means of an outlet, (D) the weight of the vessel being measured and the introduction and discharging of the suspension being controlled by means of deviations from a predetermined set value.

Abstract: A rotating tube heat treatment installation, for example a rotating tubular kiln for the thermal splitting of MgSO.sub.3, or a slag cooler for the separation of salts and aluminum, comprises as the main replaceable component, a rotating tube (1) which is surrounded by a tubular jacket (2) and separated therefrom by a gap. The tubular jacket (2) is linked to the rotating tube (1) by means of a carrier system, and has drive (8) and possible bearing races and bandings (9) mounted externally. The connections (3, 4) for the heat exchange fluid are disposed at its ends, and thermal insulation, in particular light insulation (7), is fitted internally. In this way the rotating tube, which is exposed to corrosion and thermal stresses, is simplified structurally and can be readily replaced.

Abstract: There is disclosed a process for preparing solutions of cellulose in aqueous tertiary amine oxides from a suspension of cellulose in an aqueous solution of the tertiary amine oxide by supplying heat at a reduced pressure. The suspension is transported over a heating surface, spread in layers or coats, until a homogenous solution of the cellulose has formed, which has a viscosity of between 50 and 15,000 Pas.s. Feeding of the suspension and drawing-off of the homogenous solution are carried out continuously. The solutions are prepared in an indirectly heated evacuatable vessel provided with a stirring device. The vessel is designed as a cylindrical container including a centrically mounted stirring shaft having agitators joined thereto, the radial distance of the agitators from the internal wall of the container being 20 mm at the most. There are provided an intake for the cellulose suspension in the upper part of the container and an outlet for the homogenous cellulose solution in its lower end.

Abstract: A cellulosic solution in a amine oxide and water is forced through an elongated orifice passage having a minimum length of 1000 /.mu.m and a minimum diameter along the length which is up to 150 /.mu.m so that fiber characteristics are imparted to the emerging strand which passes through an air gap of at the most 35 mm in length into the coagulating solution.

Abstract: Shaped cellulosic bodies and especially cellulosic fibers or filaments are produced by precipitating cellulose from a solution containing cellulose and NMMO. To allow elevated concentrations of NMMO in the precipitating bath without detriment to the properties of the fibers or filaments produced, the temperature of the precipitating bath is held at most at 0.degree. C.

Abstract: A solution of cellulose in water and N-methylmorpholine-N-oxide (NMMO) containing 2 to 44% by weight cellulose is stabilized at 0.01 to 1%, preferably 0.1% H.sub.2 O.sub.2 and 0.01 to 2%, preferably 0.1% of an H.sub.2 O.sub.2 stabilizer, preferably oxalic acid or a salt thereof during formation of the solution and during heating to prevent discoloration of the cellulose and reduce the composition of NMMO.

Abstract: An aqueous N-methylmorpholine-N-oxide solution which was used as a spinning bath in the production of cellulosic products is regenerated by contacting it with active coal, silicon dioxide or alumina adsorbent and filtering, thereby reducing turbidity, eliminating nitrosoamine, decolorizing the solution and removing transition metals like iron therefrom.

Abstract: For the removal of water from dilute aqueous solution of NMMO, N-methylmorpholine or morpholine or mixtures thereof, the solution is subjected to reverse osmosis at a pressure in excess of the osmotic pressure and probably around 40 bar and a temperature of 25.degree. C. to 75.degree. C. to form a retentate containing the amines and a permeate which is practically free from the amines. The permeate can be used as process water while the retentate can be worked up to NMMO for reuse in the cellulose solubilization process.

Abstract: There is disclosed a process for preparing solutions of cellulose in aqueous tertiary amine oxides from a suspension of cellulose in an aqueous solution of the tertiary amine oxide by supplying heat at a reduced pressure. The suspension is transported over a heating surface, spread in layers or coats, until a homogenous solution of the cellulose has formed, which has a viscosity of between 50 and 15,000 Pas.s. Feeding of the suspension and drawing-off of the homogenous solution are carried out continuously. The solutions are prepared in an indirectly heated evacuatable vessel provided with a stirring device. The vessel is designed as a cylindrical container including a centrically mounted stirring shaft having agitators joined thereto, the radial distance of the agitators from the internal wall of the container being 20 mm at the most. There are provided an intake for the cellulose suspension in the upper part of the container and an outlet for the homogenous collulose solution in its lower end.