[go: up one dir, main page]

WO1994028216A1 - Pompage de melanges contenant de la cellulose - Google Patents

Pompage de melanges contenant de la cellulose Download PDF

Info

Publication number
WO1994028216A1
WO1994028216A1 PCT/GB1994/001105 GB9401105W WO9428216A1 WO 1994028216 A1 WO1994028216 A1 WO 1994028216A1 GB 9401105 W GB9401105 W GB 9401105W WO 9428216 A1 WO9428216 A1 WO 9428216A1
Authority
WO
WIPO (PCT)
Prior art keywords
cellulose
mixture
pulp
pump
weight
Prior art date
Application number
PCT/GB1994/001105
Other languages
English (en)
Inventor
Gary Edward George Gray
Iain Richard Jack
Original Assignee
Courtaulds Fibres (Holdings) Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Courtaulds Fibres (Holdings) Limited filed Critical Courtaulds Fibres (Holdings) Limited
Priority to AU67285/94A priority Critical patent/AU6728594A/en
Priority to EP94915650A priority patent/EP0700461A1/fr
Priority to JP7500368A priority patent/JPH08510434A/ja
Publication of WO1994028216A1 publication Critical patent/WO1994028216A1/fr
Priority to FI955650A priority patent/FI955650A0/fi

Links

Classifications

    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D1/00—Treatment of filament-forming or like material
    • D01D1/02—Preparation of spinning solutions

Definitions

  • This invention relates to a method of conveying a cellulose containing mixture having a paste or slurry like consistency.
  • the mixture comprises cellulose, amine oxide and water.
  • the invention also relates to a system of conveying a cellulose containing liquid mixture.
  • Cellulose containing mixtures are well known in different fields of application.
  • wood processing and paper making industries there is a need to convey fiber suspensions of pulp having a relatively high consistency (i.e. percentage by weight of dry cellulose material in solution).
  • cellulose containing solution In other industries, such as the textile industry, there is the need to convey cellulose containing solution to a shaping station where the solution is adapted to be shaped and subsequently regenerated into a cellulosic product, such as a fiber or filament or cellulosic rod, tubing, plate or film.
  • An object of the present invention is to provide a method of pumping a cellulose containing liquid mixture, e.g. a cellulose-amine oxide-water mixture, using a reciprocating piston pump, e.g. a so-called concrete pump such as a double cylinder reciprocating pump.
  • a reciprocating piston pump e.g. a so-called concrete pump such as a double cylinder reciprocating pump.
  • Premixes comprising mixtures of cellulose, amine oxide and water, are particularly difficult to handle and convey without the cellulose breaking down or the amine oxide becoming separated from, or squeezed out of, the mixture. It has been found, however, that by using a reciprocating piston pump operating at relatively low reciprocating speeds, such premixes do not deteriorate in quality and the mixed components remain in a homogeneous state.
  • the method is particularly suited to premixes having a consistency (proportion of dry weight of cellulose in the mixture) in excess of 8%, e.g. at least 10% or preferably at least 12%, such as 13%.
  • the method can also be advantageously used for mixtures having consistencies in excess of 15%, e.g. up to 20%.
  • the invention is particularly suited to conveying a premix at an elevated temperature, typically in excess of 150°F, e.g. 176°F, and comprising a mixture containing cellulose dispersed in a solvent for cellulose comprising amine oxide and water.
  • a mixture comprises approximately 13 parts by weight of cellulose and 87 parts by weight of amine oxide and water.
  • the mixture comprises 13% by weight of cellulose, 72% by weight of amine oxide and 15% by weight of water.
  • the reciprocating pump is thermally lagged and may be heated, e.g. by means of a hot water jacket, to ensure that the mixture remains at an elevated temperature.
  • the solvent for cellulose comprises any suitable tertiary amine oxide which is compatible with water.
  • Preferred tertiary amine oxides are cyclic mono (N- methylamine-N-oxide) compounds such as, for example, N- methyl-morpholine-N-oxide, N-methylpiperidine-N-oxide, N- methylpyrrolidone-oxide, dimethylcyclohexylamine oxide and the like.
  • a system for preparing and conveying a cellulose containing liquid mixture comprising a premixer for mixing the constituents of the mixture, a storage hopper into which the mixture is stored and a reciprocating piston pump for conveying the mixture in the storage hopper to a further processing station.
  • Figure 1 is a schematic representation of apparatus for forming a mixture containing at least cellulose and a solvent for the cellulose;
  • Figures 2a and 2b are schematic side and sectional views, respectively, showing particulate material being deposited on the outside of a filtering sleeve;
  • Figures 3a and 3b are schematic side and sectional views, respectively, showing particulate material previously deposited on the outside of a filtering sleeve being removed therefrom;
  • Figure 4 is a schematic sectional view, on an enlarged scale, of a premixer of the apparatus shown in Figure 1;
  • Figure 5 is a part sectional view, on an enlarged scale, of a storage hopper of the apparatus shown in Figure 1, and
  • Figures 6 and 7 are, respectively, a schematic end sectional view and view from above, on enlarged scales, of part of a reciprocating dual piston pump of the apparatus shown in Figure 1.
  • Figure 1 shows schematically apparatus, generally designated by the reference numeral 1, for forming a mixture of cellulosic material dispersed in a solvent for the cellulose.
  • the apparatus 1 comprises a first set of pulp rolls 2, a second set of pulp rolls 3, a pulp shredding device 4 and associated fan 23, pulp separators 5a and 5b, filtering means 6, premixer 7a and 7b, storage hoppers 84 and 85 and reciprocating dual piston pumps 88 and 89.
  • a multi-layered first web 9 of cellulosic material is formed by drawing webs from the first set of pulp rolls 2 using a lower pair of nip rolls 8 and an upper pair of nip rolls 10. In its path between the nip rolls 8 and 10, the first web 9 is fed between a pair of spaced apart web guide plates 11.
  • a multi-layered second web 12 of cellulosic material is also formed by drawing webs from the second set of pulp rolls 3 using a lower pair of nip rolls 13 and an upper pair of nip rolls 14. The second web is guided between the nip rolls 13 and 14 by means of spaced apart guide plates 15.
  • the guide plates 11 and 15 are positioned between the nip rolls 8 and 10 and 13 and 14, respectively, so as to guide the multi-layered webs 9 and 12 between the nip rolls without the need for operator interaction.
  • the guide plates 11 and 15 are hinged for access in case during use there is a blockage between the guide plates.
  • Pulp rolls are supplied to end users on the basis of the viscosity of a liquid product produced in a predetermined manner from the pulp material. Although viscosity ratings vary from batch to batch, an end user can select stock rolls having viscosity ratings from pre-selected viscosity bands.
  • the rolls in the first set of pulp rolls 2 have a viscosity rating in a lower value band and the rolls in the second set of pulp rolls 3 have a viscosity rating in a higher value band.
  • the speed of travel of the webs 9 and 12 to the shredding device 4 is controlled to provide a mixture of pulp material having the desired viscosity rating.
  • shredded pulp from the shredding device 4 can be weighed in weighting apparatus (not shown) before the desired weight of pulp is added to the premix 7a or 7b. If this method is employed, it is assumed that the pulp rolls consist of a set percentage by weight of cellulose and a set percentage by weight of water, e.g. 94% by weight of cellulose and 6% by weight of water. Preferably, however, the bone-dry weight of pulp material is calculated as it is fed to the shredding device with the use of sensing means 16 and 17 sensing the webs 9 and 12, respectively.
  • Each sensing means 16, 17 comprises a beta ray scanner for measuring the weight per unit area of the composite layered web 9 or 12 and optionally also comprises a moisture measuring device employing microwave absorption techniques to measure the moisture content of the web 9 or 12. If moisture measurement is not employed, the moisture content of each web is considered to be about 6% by weight of the web, the remaining 94% by weight being cellulose. With signals for the weight per unit area of each web 9, 12, the width of each web and the moisture content of each web, the amount of cellulose delivered to the shredding device 4 can be calculated and this figure used to control the amount of cellulose added to each premixer.
  • Metal detectors 18 and 19 are also provided to detect for the undesirable presence of metal within the webs 9 and 12. If metal is detected the process can be automatically stopped.
  • the multi-layered first and second webs 9 and 12 of cellulosic material are fed into the inlet of the shredding device 4 where the webs are cut or comminuted into irregular flakes or particles of pulp material.
  • the shredding device 4 is provided with rotating cutter knives 20 which are designed to cut or tear the cellulosic web material with minimum compression of the cut edges of the web material.
  • a particular preferred typed of pulp shredder is the cutter manufactured by Ulster Engineering and marketed by Birkett Cutmaster Limited known as the "AZ 45 Special". Such a shredder is provided with a knife type cutter (type 31 mm x 7 hook) .
  • the rotating knives 20 of the shredding device 4 rotate at approximately 140 rpm and cut the cellulosic material into irregular shapes or flakes up to about 1 to 20 cm 2 , typically from about 3 to 15 cm 2 .
  • the cutter knives also generate a quantity of much finer cellulosic particles or "pulp dust".
  • up to 99% of the web material is cut into these larger flakes or particles of cellulosic material with the remaining 1% being formed into pulp dust.
  • the cut and shredded pulp material exits from the outlet of the shredding device 4 and is conveyed via circular section ducting 21 to a diverter valve 22.
  • the pulp material is conveyed in an air stream created by the air fan 23 at the outlet of the shredding device 4 which sucks in air at air inlet A through a filter 24.
  • This fan has vanes which are fitted with cutting blades and these help to shred and break up further the particles of cellulosic material exiting from the shredding device 4.
  • the process operates as a batch process and, depending on which part of the batch process is in operation, the diverter valve 22 directs the cut pulp from ducting 21 either via ducting 25 to the pulp separator 5a or via ducting 26 to the pulp separator 5b.
  • the pulp separators 5a and 5b operates in a similar manner and only pulp separator 5a will be described in detail hereafter.
  • the pulp separator 5a has an inlet 27, a first outlet 28 arranged in line with the first inlet 27 and a second outlet 29 offset from a path between the inlet 27 and first outlet 28.
  • a mesh screen 30 is arranged at an angle between the direct path between the inlet 27 and first outlet 28.
  • the cut pulp material including the pulp dust is conveyed in a stream of air via the ducting 25 through the inlet 27 and is directed towards the first outlet 28.
  • the mesh screen 30 has a mesh size of 0.1 inch (2.54mm) and allows the pulp dust, up to a particle size of 0.1 (2.54mm) inch and the conveying air stream to pass therethrough and out through the first outlet 28.
  • the larger particles of cut cellulosic material which are too large to pass through the mesh of the screen 30, are deflected by the angled screen 30 downwardly through the second outlet 29.
  • the pulp dust and conveying air stream which exits from the first outlet 28 is passed via ducting 31 and 32 to an inlet of the filtering means 6.
  • the filtering means 6 serves to extract the pulp dust from the conveying air stream.
  • a particularly suitable form of filtering means 6 comprises the JETLINE V filter manufactured by NEU Engineering Limited of Woking, Surrey, England.
  • Such a filtering means 6 has a plurality of filter sleeves 40 (see Figures 2a, 2b, 3a, 3b) arranged vertically in rows, e.g. twelve rows of eight filter sleeves per row.
  • Each filter sleeve 40 of just under 1 m 2 gives a total area for all 96 sleeves of 100m 2 square section conveniently comprising needle-felt sleeve which is supported on a rigid vertical frame 41 made of anti-corrosion steel wire.
  • the filtering means 6 operates under positive pressure, the pulp dust laden inlet air being blown upwardly and radially inwardly through the tubular filter sleeve 40 in the direction of the arrows in Figure 2a.
  • a "cake” 42 of pulp dust builds up on the outside of the sleeves 40 and "clean” air is conveyed upwardly through a venturi shaped outlet tube 44. Clean air exits at 45 (see Figure 1) in the direction of arrow B.
  • the cakes 42 of pulp dust are removed from the filter sleeves 40 by pulsing air periodically downwardly through the integral venturi tube 44, with each row of filter tubes being cleaned in turn.
  • Each cleaning process involves injecting compressed air downwardly via duct 46 from compressed air line 47 into each sleeve 40 via the venturi tube 44. This momentarily reverses the air flow through the filter sleeve and abruptly inflates the filter sleeve thus throwing off the cake of pulp dust (see Figure 3a and 3b).
  • the pulp dust removed from the filter sleeves 40 drops into a storage hopper 50 at the bottom of the filtering means 6.
  • the storage hopper 50 has four sides angled inwardly and downwardly towards a rotary valve 51.
  • Each of the four walls of the hopper 50 are provided with a pair of blow nozzles 52 which are periodically operated to prevent the pulp dust accumulating on the angled side walls of the hopper 50.
  • pulp dust is conveyed via ducting 56 to a diverter valve 57.
  • the diverter valve 57 either diverts the flow of pulp dust via ducting 58a to cyclone separator 59a or via duct 58b to cyclone separator 59b.
  • pulp dust exits from the latter and is conveyed via ducting 60 to T-into a duct 62 leading from the second outlet 29 of separator 5a.
  • a rotary valve 61 is provided in ducting 60 and a further rotary valve 63 is provided in ducting 62 adjacent its inlet end. Provided these valves 61 and 63 are turning, the pulp dust conveyed via ducting 60 is re-combined with the larger particles of cut cellulosic material separated by the pulp separator 5a. Outlet air from the cyclone separator 59a is cycled back to the separating means 6 via ducting 70 in order to extract any further pulp dust which still might be present in the air exiting from the cyclone 59a.
  • the separator 5b is brought into operation when the diverter valve 22 is set to divert the cut pulp and conveying air via ducting 26. Pulp dust exists from the first outlet of the separator 5b and is conveyed via ducting 72 and 32 to the filtering means 6.
  • the diverter valve 57 ensures that pulp dust from the filtering means 6 is diverted via ducting 58b to the cyclone separator 59b from where pulp dust passes via outlet 74 for re-combination with coarser particles of cellulosic material separated in the separator 5b and exiting via ducting 75. This re ⁇ combination of pulp dust proceeds when rotary valves 76 and 77 are operational and not in their stationary condition.
  • the shredded pulp and pulp dust from the ducting 62 and 75 is fed to inlets 80 and 81, respectively, of the premixers 7a and 7b, respectively, depending on which batch is being processed.
  • Each of the inlets 80 and 81 is conveniently heated by means of a hot water jacket 82 (see Figure 4) through which hot water, e.g. at 120°F (49°C) is circulated.
  • the hot water is supplied via hot water supply pipe 82a and is returned via hot water return pipe 82b.
  • the premixer 7a has four further inlets 83 (only one of which is shown) for the introduction therein of a water solution of tertiary amine oxide, the mixture consisting of 78% parts by weight of amine oxide and 22% parts by weight of water.
  • a particularly preferred tertiary amine oxide is N-methyl-morpholine-N-oxide.
  • the temperature of the amine oxide solution is carefully controlled to a desired temperature of approximately 180°F (82°C), e.g. 176°F (80°C), prior to its introduction into the premixer.
  • the amount of amine oxide solution introduced into the premixer 7a is carefully controlled by a mass flow meter and a valve 83c in supply line 83d so as to produce a mixture with the added pulp consisting of approximately 13 parts by weight of cellulosic material and 87 parts by weight of amine oxide and water.
  • a mass flow meter and a valve 83c in supply line 83d so as to produce a mixture with the added pulp consisting of approximately 13 parts by weight of cellulosic material and 87 parts by weight of amine oxide and water.
  • approximately 80001b of amine oxide solution and approximately 12001b of shredded pulp are added to the premixer.
  • a stabiliser such as powdered propyl gallate, is also conveniently added to each premixer for mixing with the other materials.
  • the stabiliser is added to prevent or reduce the decomposition of the amine oxide and the decomposition of the cellulose. It is suitably added to the shredded pulp just prior to the latter being introduced into the premixer.
  • Other additives may be added at this stage. Examples of such additives are dulling agents, e.g. titanium dioxide, viscosity modifiers and pigments.
  • the premixer 7a comprises a mixing chamber within which is mounted a horizontal shaft 65 having radial paddles 65a extending therefrom.
  • the paddles 65a are in the form of plough blade stirrers and extend radially conveniently in different axial planes.
  • the horizontal shaft 65 is driven by an externally mounted motor and rotates relatively slowly at approximately 72 r.p.m..
  • Mounted in line in the walls of the mixing chamber of the premixer 7a are four spaced apart refiner mixers 67 (only one of which is shown in Figure 4) each driven by an externally mounted motor 67a to rotate relatively quickly at speeds of approximately 3000 r.p.m.
  • the axis 68 of rotation of each refiner blade is orthogonal to the axis of rotation of the slowly rotating paddles 65a, which rotate at tip speeds in the range 4 to 6 m/s, preferably 5-5.5 m/s.
  • the quickly rotating refiner mixers 67 are primarily intended to chop up the larger particles of shredded pulp after the latter have swollen in the amine oxide solution.
  • the slowly rotating paddles are intended to mix the introduced components together to facilitate dispersion of the cellulose in the amine oxide solution.
  • the combined actions of the slowly rotating paddles 65a and the quickly rotating refiner mixers 67 produces a homogeneously mixed mixture of the cellulosic material dispersed in the amine oxide and water.
  • the items 65c, 67b and 83e shown in Figure 4 represent part of an electronic computer control system for automatically controlling the entire process and, in particular, the motor 65b, the motors 67a and a mass flow meter upstream of valve 83c, respectively.
  • each premixer which provides the walls of the mixing chamber, has heating jackets 69 around which hot water, typically at a temperature of about 180°F (82°), e.g. 176°F (80°C), is circulated to retain the contents of each mixing chamber at an elevated temperature of about 180°F (82°C), e.g. 176°F (80°C).
  • Hot water is supplied via supply pipe 69a and is returned for re-heating via return pipe 69b.
  • Each mixing operation typically takes about 21 minutes to perform.
  • the amine oxide solution is initially loaded into the premixer in about 5 minutes and the pulp and added propyl gallate are subsequently loaded over a period of about 10 minutes.
  • Mixing then proceeds for at least four minutes, typically for about 6 minutes, at an elevated temperature of about 180 ⁇ F (82°C), e.g. 176°F (80°C), in which time a high quality mixture is obtained in which the cellulosic material is broken down into discrete individual fibers which are substantially uniformly dispersed in the tertiary amine oxide.
  • an elevated temperature of about 180 ⁇ F (82°C), e.g. 176°F (80°C)
  • a high quality mixture is obtained in which the cellulosic material is broken down into discrete individual fibers which are substantially uniformly dispersed in the tertiary amine oxide.
  • the result is a premix having a relatively high cellulose content of about
  • the premix can subsequently be converted under the action of heat and pressure into a viscous dope in which the cellulose is dissolved in the amine oxide solution, the dope so produced being suitable for subsequently producing cellulosic products.
  • a particularly suitable mixer has been found to be the RT3000 Model Mixer manufactured by Winkworth Machinery Limited at Swallowfield, Near Reading, Berkshire, United Kingdom.
  • the premixers 7a and 7b have valved bottom outlets 82a and 82b which are connected, respectively, to the inlets 83a and 83b of vertical storage hoppers 84 and 85.
  • the hoppers 84 and 85 have outlets 86 and 87, respectively, which are connected to inlet sides of reciprocating piston pumps 88 and 89, respectively.
  • the pumps 88 and 89 have outlet pipes 90 and 91, respectively, connected to a dope making stage (not shown).
  • the mixture is either passed from premixer 7a, via the storage hopper 84 to the piston pump 88 for conveyance via outlet pipe 90 to the dope making stage or is passed from premixer 7b, via the storage hopper 85 to the piston pump 89 for conveyance via outlet pipe 91 to the dope making stage.
  • the storage hoppers 84 and 85 serve to maintain the mixture formed in the premixers 7a and 7b, respectively, in a mixed homogeneous condition of the correct consistency and viscosity. Since the storage hoppers 84 and 85 are identical and the reciprocating piston pumps 88 and 89 are identical only storage hopper 84 and piston pump 88 will be described in detail hereafter.
  • the storage hopper 84 (shown schematically in Figure 5) is arranged vertically and has a circular cylindrical upper portion 84a and a frusto-conical lower portion 84b.
  • Heating pipes 84c are arranged on the outside of the portions 84a and 84b for passing hot water around the walls of the hopper to maintain the contents of the hopper at an elevated temperature of about 180°F (82°C), e.g. 176°F (80°C).
  • Hot water is supplied via inlets 84h and 84i and is returned via outlets 84j and 84k.
  • a vertical, axially disposed shaft 84d carrying axially spaced apart radial arms 84e is rotatable at a relatively slow speed of from 2-10 r.p.m., e.g. 8 r.p.m..
  • the shaft 84d is supported by an upper bearing (not shown), a lower bearing 84g and an intermediate bearing carried by radial arms 84p.
  • Axially adjacent pairs of the arms 84e carry a common stirrer 84f, with four such stirrers 84f being shown in Figure 4.
  • These stirrers 84f are positioned at the radially outer extremities of the arms 84e and in use sweep out stirring paths adjacent the walls of the hopper 84.
  • stirrers 84f act to stir premix contained in both the upper portion 84a and the lower portion 84b of the storage hopper 84.
  • Figure 5 only half the numbers of arms 84e and stirrers 8 f are shown since corresponding arms and stirrers (not shown) extend on the right hand side of the hopper 84, each arm on the right hand side being diametrically in line with its corresponding arm 84e.
  • the arms 84e carrying the lower stirrer 84f in the upper portion 84a and the arms 84e carrying the lower stirrer 84f in the lower portion 84b are also aligned in a common plane which is offset, e.g. 90°, from the axial plane containing the other radial arms 84e. It will be appreciated that Figure 5 is only schematic since the offset radial arms are all shown.
  • the premix passed into the storage hopper 84 can be kept in a viscous usable condition at the correct elevated temperature for a desired period of time, e.g. up to several hours.
  • the relatively slowly rotating stirrers 84f keep the cellulose dispersed in the amine oxide solution so that the mixture remains in a homogeneous condition.
  • the premix. can thus be kept in a usable condition for a period of time before being transported to the dope forming stage and serves to provide a useful degree of control in the production process.
  • the storage hopper 84 provides a break in the process and is able to absorb any discontinuities upstream, e.g. caused by having to stop the process for system failures or the like, without the need to discard the already mixed premix.
  • the reciprocating piston pump 88 is a dual piston, hydraulically actuated so-called "concrete pump".
  • a particularly suitable concrete pump is the Schwing Type KSP 17 HD EL pump manufactured by Schwing GmbH.
  • Such a concrete pump 88 is found to be particularly suitable for conveying the premix to the dope forming stage without the premix losing its homogeneity.
  • the premix is delivered, on opening of a valve 95, through an outlet of the hopper 84 into an inlet 96 (see Figures 6 and 7) of the pump 88.
  • the premix On the suction stroke of one of the pistons of the dual piston pump, the premix is drawn through the outlet of the hopper into one of the two cylinders 97, 98 of the pump 88.
  • the premix previously drawn into the cylinder is pushed forward through a transfer tube 99 for conveyance through the outlet pipe 90.
  • the transfer pipe 99 is mounted on pivot shaft 100 and, on actuation of an hydraulic ram 105, is pivotally movable between a position shown in full lines in Figure 7 in which the cylinder 98 is connected to the pipe 90 and a position shown in dashed lines in Figure 7 in which the cylinder 97 is connected to the pipe 90.
  • opening 101 (shown in chain lines) is the inlet of the outlet pipe 90 and openings 102 and 103 are at the ends of the cylinders 97 and 98, respectively.
  • the reciprocating piston pump 88 is found to be robust in use and provides a positive pumping action for conveying the cellulosic premix.
  • the relatively slowing reciprocating pistons do not "squeeze out” and separate the amine oxide from the cellulose to any significant degree and do not break down the cellulose. This is primarily because a large proportion of the kinetic energy of the moving pistons is used to move the premix.
  • the pump acts as a metering pump.
  • each cylinder Since the volume of each cylinder is known and since each cylinder is filled with premix on a suction stroke, the amount of premix discharged on each discharge stroke can be accurately determined. Thus the amount of premix being conveyed over a period of time can be accurately controlled by controlling the speed of the reciprocating pistons.
  • the pump is relatively reliable in use, does not cause the cellulose to be separated out from the amine oxide and accurately meters the premix.
  • the premix contains approximately 13% by weight of cellulose and the reciprocating piston pump is able to pump the premix reliably and effectively.
  • the premix from the pumps 88, 89 is conveyed via hot water traced pipes 90,91 to a dope forming stage, the dope so formed subsequently being shaped and regenerated into a cellulosic product, such as a fiber, filament, rod, tubing, plate or film.
  • the pipes 90 and 91 are provided with valves 92a and 92b, respectively, and reciculating pipes 93a and 93b are connected upstream of the valves 92a and 92b for connecting the outlets of the pumps 88 and 90 to inlets of the storage hoppers 7a and 7b.
  • the recirculating pipes 93a and 93b incorporate valves 94a and 94b, respectively.
  • premix can be pumped around closed circuits including the storage hoppers 7a and 7b without having to be pumped to the dope forming station.
  • these valves can be closed and the mixture can be recirculated back to the storage hoppers.
  • the outlet pipes 90 and 91 are also lagged.
  • the steps of controlling the feeding of web from the paper rolls to the shredding apparatus, of supplying the shredded pulp to the premixers including the step of recovering fine particles filtered from the shredded pulp, of adding desired quantities of premix constituents to the premixers, of mixing the premix constituents in the premixers, of stirring the formed premix in the storage hoppers and of pumping the premix to a dope forming stage is preferably automatically controlled under computer control.
  • the invention finds application in the textile industry for the production of cellulosic products.

Landscapes

  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)

Abstract

L'invention concerne un procédé d'acheminement d'un mélange relativement visqueux contenant de la cellulose, tel qu'un prémélange de cellulose dispersée dans une solution d'oxyde d'amine et d'eau, cet acheminement étant effectué à l'aide d'une pompe à piston alternatif, par exemple une pompe à béton.
PCT/GB1994/001105 1993-05-24 1994-05-20 Pompage de melanges contenant de la cellulose WO1994028216A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
AU67285/94A AU6728594A (en) 1993-05-24 1994-05-20 Pumping of cellulose containing mixtures
EP94915650A EP0700461A1 (fr) 1993-05-24 1994-05-20 Pompage de melanges contenant de la cellulose
JP7500368A JPH08510434A (ja) 1993-05-24 1994-05-20 セルロースを含む混合物のポンピング
FI955650A FI955650A0 (fi) 1993-05-24 1995-11-23 Selluloosaa sisältävien seosten pumppaaminen

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US6743093A 1993-05-24 1993-05-24
US08/067,430 1993-05-24

Publications (1)

Publication Number Publication Date
WO1994028216A1 true WO1994028216A1 (fr) 1994-12-08

Family

ID=22075931

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1994/001105 WO1994028216A1 (fr) 1993-05-24 1994-05-20 Pompage de melanges contenant de la cellulose

Country Status (8)

Country Link
EP (1) EP0700461A1 (fr)
JP (1) JPH08510434A (fr)
AT (1) AT1083U1 (fr)
AU (1) AU6728594A (fr)
FI (1) FI955650A0 (fr)
TR (1) TR28394A (fr)
TW (1) TW283755B (fr)
WO (1) WO1994028216A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6547999B1 (en) 1999-10-18 2003-04-15 Viskase Corporation Cellulose food casing, cellulose composition and production method therefor

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012068352A2 (fr) * 2010-11-17 2012-05-24 Danny Ness Réservoir de mélange et procédé d'utilisation

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4178142A (en) * 1976-07-21 1979-12-11 Friedrich Wilh. Schwing Gmbh Double-cylinder pump especially for conveying cement
US4416698A (en) * 1977-07-26 1983-11-22 Akzona Incorporated Shaped cellulose article prepared from a solution containing cellulose dissolved in a tertiary amine N-oxide solvent and a process for making the article
EP0356419A2 (fr) * 1988-08-16 1990-02-28 Lenzing Aktiengesellschaft Procédé pour produire des solutions de cellulose
WO1994006530A1 (fr) * 1992-09-17 1994-03-31 Courtaulds Fibres (Holdings) Limited Formation de solutions

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4178142A (en) * 1976-07-21 1979-12-11 Friedrich Wilh. Schwing Gmbh Double-cylinder pump especially for conveying cement
GB1569922A (en) * 1976-07-21 1980-06-25 Schwing Gmbh F Double-cylinder pump especially for conveying cement
US4416698A (en) * 1977-07-26 1983-11-22 Akzona Incorporated Shaped cellulose article prepared from a solution containing cellulose dissolved in a tertiary amine N-oxide solvent and a process for making the article
EP0356419A2 (fr) * 1988-08-16 1990-02-28 Lenzing Aktiengesellschaft Procédé pour produire des solutions de cellulose
WO1994006530A1 (fr) * 1992-09-17 1994-03-31 Courtaulds Fibres (Holdings) Limited Formation de solutions

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6547999B1 (en) 1999-10-18 2003-04-15 Viskase Corporation Cellulose food casing, cellulose composition and production method therefor

Also Published As

Publication number Publication date
FI955650L (fi) 1995-11-23
AT1083U1 (de) 1996-10-25
TR28394A (tr) 1996-05-23
FI955650A0 (fi) 1995-11-23
JPH08510434A (ja) 1996-11-05
AU6728594A (en) 1994-12-20
EP0700461A1 (fr) 1996-03-13
TW283755B (fr) 1996-08-21

Similar Documents

Publication Publication Date Title
EP0700462B1 (fr) Formation d'un premelange a base de cellulose
US5456748A (en) Premix storage hopper
EP0700460B1 (fr) Filtration d'une matiere particulaire a base de cellulose
AT409130B (de) Verwendung einer vorrichtung zum halten und abgeben einer homogenen cellulosesuspension
EP1007228B1 (fr) Appareil pour fragmenter et separer les particules
KR100798213B1 (ko) 라이오셀 섬유 제조 방법 및 장치
WO1994028216A1 (fr) Pompage de melanges contenant de la cellulose
CN1235912C (zh) 一种在氧化胺水溶液中的纤维素悬浮液的连续制备方法及装置
CN107266592A (zh) 具有高堆积密度的水溶性非离子型纤维素醚粉末的制造方法
US20020079074A1 (en) Feather processing method and product
GB2115681A (en) Tobacco lamina and stem processing
RU2038846C1 (ru) Устройство для рыхления и жидкостной обработки волокнистых материалов
JPS6071556A (ja) ガラス繊維強化セメント複合材料の製造方法
RU2356910C1 (ru) Установка для непрерывного получения натриевой соли карбоксиметилцеллюлозы
CZ1212U1 (cs) Zařízení pro výrobu omítkových hmot na bázi celulózy

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AT AT AU BB BG BR BY CA CH CN CZ DE DE DK ES FI GB HU JP KP KR KZ LK LU LV MG MN MW NL NO NZ PL PT RO RU SD SE SI SK TT UA UZ VN

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1994915650

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 955650

Country of ref document: FI

WWP Wipo information: published in national office

Ref document number: 1994915650

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: CA

WWW Wipo information: withdrawn in national office

Ref document number: 1994915650

Country of ref document: EP