CN1867732A

CN1867732A - Method for loading a fibrous substance suspension and arrangement for carrying out this method

Info

Publication number: CN1867732A
Application number: CNA2004800300091A
Authority: CN
Inventors: 洛撒·法尔泽; 克劳斯·多尔
Original assignee: Voith Paper Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2003-10-31
Filing date: 2004-09-28
Publication date: 2006-11-22
Also published as: WO2005042841A1; DE10351292A1; BRPI0416090A; US20070068640A1; EP1682722A1

Abstract

A method for loading a fibrous substance suspension, which contains cellulose fibers, with calcium carbonate, comprises the following method steps: introducing calcium hydroxide in liquid or dry form or calcium oxide into the fibrous substance suspension; introducing gaseous carbon dioxide into the fibrous substance suspension; precipitating calcium carbonate by the carbon dioxide; triturating the fibrous substance suspension during the loading process, and; washing the fibrous substance suspension after the crystallization process and/or before the triturating process and/or during the triturating process and/or after the triturating process.

Description

The method of load fibers material suspension and the equipment of implementing this method

The present invention relates to load the method for the fibrous substance suspension that contains cellulose fibre with calcium carbonate.

If when fibrous substance suspension was pressed fiber one loading one PROCESS FOR TREATMENT, precipitation of calcium carbonate was come out, this technology for example has description in DE101 13 998 A1.

Task of the present invention is to set up a kind of other method that is used to prepare with the calcium carbonate load fibers:

Implement this task by the present invention by the method for following operation:

● make to be in a liquid state or the calcium hydroxide of dry state or calcium oxide add in the fibrous substance suspension;

● gaseous carbon dioxide is added in the fibrous substance suspension;

● use the carbon dioxide winnofil;

● milled fibre material suspension and in loading procedure at washing the fibre material suspension behind the crystallization process and/or before process of lapping and/or in process of lapping and/or behind process of lapping.

The method that this task also can be selected to have following operation is finished:

● make to be in a liquid state or the calcium hydroxide of dried forms or calcium oxide add fibrous substance suspension;

● gaseous carbon dioxide is introduced fibrous substance suspension;

● use the carbon dioxide winnofil;

● fibrous suspension is introduced the hopper that install in fibrous substance suspension flow direction downstream, and/or introducing is used for reprocessing before the machine of fibrous substance suspension washing fibrous suspensions.Respectively before or after grinding step, adopt fiber-loading-technology by final products institute requirement.

By the method that the present invention describes, the calcium carbonate with the fiber loading (the FLPCC=fiber loads the calcium carbonate of precipitation) for the preparation precipitation particularly is used for the cellulose manufacturing or is used for fiber applications in papermaking.The fibrous material that loads, for example by reclaiming paper, by DIP (deinking paper), by the secondary stock material, bleaching or unbleached fibrous matter, all kinds of lignin, various paper material fiber (papierrohzellstoff), bleaching or unbleached sulfate fiber, the waste product of rapidoprint (Fertigstoff ausschuss) flax-, cotton-and/or other the paper material of paper that hemp (being mainly used in cigarette) and/or all are used on paper machine prepare.

Can unrestrictedly use by the inventive method, no matter whether contain filler in the final products, this product is to prepare (GCC=grinding calcium carbonate) or wherein use talcum powder, silicon, titanium dioxide (TiO jointly at batch reactor or with grinding technics with depositing technology ₂).

The FLPCC-technology that is described below is the filler that other preparation method uses, and its filler with fiber-loading-prepared replaces.Extend to the Application Areas of papermaking and all paper product kinds with the filler of fiber-loading-prepared, comprise wrapping paper, the content of its filler is between 1%～60%, and perhaps it is the covering layer of the white of filer content between 1%～60%.

Application Areas of the present invention is not limited to and uses this filler in paper technology, and the present invention can comprise application in the fiber manufacturing at various paper-making process or supporting process.If with fiber-loading-PROCESS FOR TREATMENT, the result obtains a kind of new product fully to fibrous suspension in papermaking, it has new more performance than product known on the market.The technology that describes below can be directly be settled out filler (calcium carbonate) in the material in paper mill is prepared, this filler finally distributes equably and is deposited on the fibrous matter, particularly paper fiber or therein.

The combination of the form of implementation of the present invention by following description or separately application can reach preparation and have separately the fibrous matter that the calcium carbonate of precipitation loads, in this tosca on fiber or in the fiber or be deposited on wherein, the formation of the disconnected calcium carbonate (PCC) that freely precipitates hereinto.Behind the process of lapping and/or in process of lapping and/or behind the crystallization process at crystallizer and/or before the material gathered trough, or the basin that sends back to storage tank or send back to other entrance side before sending into paper machine or by pressing filtering liquid is by adopting additional washing process, can make the content of calcium hydroxide in the feeding system of fiber-loading-equipment be calibrated to constant or adjusts to constant.Calcium hydroxide can directly add the fibrolysis device, and pressing filtering liquid turns back to the material dissolution system.Do not get transformed into the calcium hydroxide of calcium carbonate or calcium hydroxide that it is not deposited on the fiber or in the fiber as yet and send back to the operation that connects previously again.

Has only the filler that is not deposited on the fiber or in the fiber, that is the calcium carbonate of free settling washs out it, fiber outside and the inner fiber itself that has filler are removed and pressing filtering liquid does not circulate by washing process, and fiber-loading-technology can keep its favourable influence like this.

In the form of implementation of describing in detail below replenishing of the present invention, the embodiment that further describes with reference to US 6,413 365, DE10107448 A1 and DE101 13 998 A1 implements to press method of the present invention with this embodiment is same.

The present invention is particularly including a kind of method, and according to said method fibrous suspension injects a press device to extrude filtrate.Filtrate to small part is sent back in the flow process with the dissolving fibrous substance suspension the most at last, promptly delivers in the basin of entrance side, for example delivers in the hopper, and calcium hydroxide to small part is sent in the flow process with the dissolving fibrous matter.In whole material dissolution system, promptly be used for the device of the dissolving of fibrous material on stream, pH value maintains between 7～12, particularly between 8～12.

Adopting moisture fibrous material, particularly denseness by the present invention is 0.1%～20%, and preferably 2%～8% moisture paper material is as raw material.

The calcium hydroxide or the calcium oxide of moisture or dried forms are mixed into moisture paper fibrous matter at existing solid material content in 0.01%～60% scope.Mixed process adopts static mixer, and hopper or a substance solution system adopt pH value in 7～12 scopes, preferably between 9～12 at this.The reactivity of calcium hydroxide is between 0.01～180 second, preferably between 0.05～60 second.Sneak into dilution water by predefined response parameter, so that make moisture raw material.

Carbon dioxide is sneaked in the wet paper material suspension with corresponding response parameter.Be precipitated out in carbon dioxide atmosphere at this calcium carbonate.

Paper siccative simultaneously per ton uses the grinding energy of 0.1～300kwh scope, compares with traditional producd fibers material suspension technology, and the inventive method reaches higher lapping degree with more rational energy consumption.Can save at least 50% by the present invention and grind energy.This all produces effect to all carry out grinding technics in it is produced paper especially, in these paper grades especially to having the kind of high or very high lapping degree, for example, FL-cigarette paper (loading of FL=fiber), FL-B﹠amp; P-paper, FL-paper bag brown paper and FL-filter paper.These paper are not needed filler, and free filler is not deposited on the fiber or in the fiber, can remove at grinding step or before fibrous substance suspension is introduced the raw feed materials groove or before sending into paper machine.But the inside and outside filler that also has of fiber itself, also there is advantageous effects in fiber-loading-technology like this.

The high mechanical properties of the final products that reach by high lapping degree all produces advantageous effects to the production of all paper product kinds, FL-cigarette paper particularly, FL-B﹠amp; P-paper, FL-paper bag brown paper and FL-filter paper, reason is in the mechanical load of the technology decision different workshop sections at paper machine, for example in compacting workshop section, dry workshop section or in the zone that paper web is rolled, intermediate product of producing and the final products that will produce are owing to use roller press (Aufroll-), wrapping machine (Wickel-), rewinding machine (Umroll-), interpreter (Konvertierung).Particularly when producing cigarette paper, on cigarette paper, form high mechanical load.

This is in other cases owing to adopt wrapping machine and because low face is heavy is limited when making cigarette.

By also created the prerequisite of better drying by the preliminary treatment of fibrous substance suspension of the present invention, in the production of all paper product kinds, improved efficient by it, its advantage makes residue humidity in 1%～20% scope.

Producing the paper of all kinds with the inventive method, or the cardboard of cardboard or various types of service, be included in white covering layer on the ply of board and all can reach higher whiteness and/or higher higher optical value with high brightness preferably to 15 luminance points.

The introducing of control energy in process of lapping, i.e. heat and by its heating that causes, control corresponding can make multi-form crystal.

The present invention relates to other the layout on a kind of method, adopt static mixer as reactor therein, purifier, disperser and/or Fluffer-FLPCC reactor, fiber content wherein, especially paper content contains between 0.01%～15% at static mixer, contains 2%～40% at purifier and disperser, especially contain 2%～8% and contain 20%～35% at the LC-mill, and contain 15%～60% at the Fluff-FLPCC reactor at the HC-mill.

The present invention relates to a kind of method equally, and particularly precipitation reaction according to said method adopts energy consumption between 0.3～8kwh/t, particularly between 0.5～4kwh/t without grinding technics the time.

Technological temperature is preferably between-15 ℃～120 ℃, particularly at 20 ℃～90 ℃.Preferably generate rhomboidan (Rhomboedrische), triangle (skalenohedrische) and spherulite, wherein crystalline size is between 0.05 μ m～5 μ m, particularly between 0.3 μ m～2.5 μ m.

For producing a kind of fibrous suspension that calcium carbonate loads that has, adopt static and/or dynamic, the hybrid element of Zhuan Donging particularly.

This method preferably in pressure limit at 0bar～15bar, particularly between 0～6bar, carry out.The same preferred pH value of the method particularly carries out between 6.5～9.5 between 6～10.This reaction time between 0.01～180 second, particularly between 0.05～60 second.

By above-mentioned paper product kind of carrying out the time, other advantage of technology of the present invention is that it also can continue processing on calender, therefore adopting fiber-loading-technology, make fiber-loading-particle be deposited in the fiber or fiber around or on fiber, can avoid its blackening is black glaze polishing reason (Schwarzsatinage).

Compare with the fibrous material of traditional mode of production with the fiber of producing by fiber of the present invention-loading-group technology-technology and to have higher water separation capability, it is between 5～100ml CSF or between 0.2～150SR and depend on the required lapping degree and the content of stuffing.This fiber has lower about 2～25% moisture holding capacities, and this is to depend on the raw material that is used to produce paper.Comparing water with traditional fibrous material can remove from fibrous suspension quickly, and makes the faster drying of fibrous material relatively.This also is a kind of positive influences to regain.Therefore regain is very little at paper-making process, and the impressionability of the kind of the paper produced is also had positive influences.

The present invention also relates to implement the equipment of one of said method.This is in the dehydrating threaded rod front and is added with a wherein static mixer of washing fibrous suspensions.

Another one of the present invention arranges that the filtrate of the fibrous suspension that obtains sends back to hopper by pipeline or delivers in the other bunkerage and handle with the preparation that is used for fibrous suspension in dehydrating threaded rod.

Preferably, an additional static mixer of washing fibrous suspensions therein is housed in the crystallizer front.

What have advantage equally is to arrange an additional wash mill to be used for washing fibrous suspensions in the crystallizer back.

Arrange it is that an additional static mixer is arranged in the crystallizer front at the another kind of device, fibrous suspension mixes with filtrate and/or with calcium hydroxide suspension therein.

Be that the present invention describes in force in more detail below, they are:

● Fig. 1 is the preparation that is used at the fibrous suspension of machine producd fibers material web (Fasertoffbahn).

● Fig. 2 is second kind of scheme

Being used for fibrous suspension is a pipeline system (Fig. 1), and this pipeline is furnished with control valve 2,3.Control valve 2 is contained on the pipeline 4, is connected with a static mixer 5 by pipeline 4 pipeline systems 1.By valve 6 dilution water and/or the preferred filtrate that is connected with calcium hydroxide are sent into blender 5.Blender 5 back connect a groove 7 or a container that is used to store fibrous suspension on the flow direction of fibrous suspension.By groove 7 usefulness pumps 8 fibrous suspension is pumped into another static mixer 9.Blender 9 is also sent into dilution water by valve 10.Equally by being contained in the inflow of the valve 11 control calcium hydroxide suspensions on the pipeline 12.

This is regulated by device for formulating 13, therein solid oxidation calcium or calcium hydroxide is put into water, imports water at this device for formulating 13 by pipeline 14 usefulness valves 15.The suspension that makes at device for formulating 13 imports pipeline 12 with pump 16.

Therefore flow out the fibrous suspension that mixes with calcium hydroxide by blender 9 and deliver to dehydrating threaded rod 19 with valve 18 in pipeline 17, extract water therein out from fibrous suspension, for example this water turns back to blender 5 as dilution water by pipeline 20.Another kind of mode or the water of extracting out at dehydrating threaded rod 19 in addition also can import material storaging tank 21 to be used for fibrous suspension, or it can send back to blender 9, under any circumstance, its pH value of aggregation of storing at dehydrating threaded rod 19 improves owing to the backflow of the water that contains calcium hydroxide and regulates.

The fibrous suspension that is flowed out by dehydrating threaded rod 19 passes through pipeline 22 to homogenizing screw rod 23, so that fibrous suspension becomes even.In its flow direction downstream a container (crystallizer) is installed at pipeline 24 again.This crystallizer is connected with carbon dioxide-basin 30 by a pipeline 29 that is equipped with

valve

26,27 and pump 28 and is used for the charging of carbon dioxide.Basin imports crystallizer 25 with carbon dioxide thus so that the precipitation reaction of required calcium hydroxide and carbon dioxide form calcium carbonate with in the fiber of fibrous material as filler.

By another pipeline 31 that is branched out by pipeline 29, it is furnished with a valve 32, and carbon dioxide-basin 30 is connected with homogenizing screw rod 23 in addition.Therefore can import carbon dioxide at this, so that there to small part generation precipitation reaction.

Same pipeline 29 links to each other with a static mixer 34 by another valve 33, and it is used for adding carbon dioxide by a pipeline 36 of being furnished with valve 35 again from the fibrous suspension that crystallizer 25 flows out.

Flow out fibrous suspension mixed storage tank 37 from blender 34.One filter 38 is installed between blender 34 and blending tank 37, is sent back to storage tank 7 or other bunkerage with prepared and diluted water or fibrous suspension from the come out filtrate of enrichment calcium carbonate of filter 38.Mixed storage tank 37 is equipped with the mixing fully that rotor 39 is used for fibrous substance suspension.The fibrous suspension that flows out from blender 34 flows directly to the material pot of paper machine again or carries out further mechanical treatment.For example enter in concise device-charging-case.

Can be from pipeline system 1 by valve 3 with the valve 3 of pipeline 40 wherein is installed, the conveying fiber material suspension is to blender 34, and it does not add calcium hydroxide as yet.

In addition, by the machine for preparing fibrous material breadth (Faserstoffbahn).Particularly, for example making the fresh water (FW) that reclaim in the machine screen barrier, or, sending back to container 21 as above-mentioned fibrous suspension from dehydration worm screw 19 by the plain boiled water (Wei β wasser) or the fresh water (FW) of paper machine.This for example can carry dilution water by pipeline 41 usefulness valves 42.

Flow out the dilution water that mixes with fresh water (FW) from container 21 and pass through pipeline 43, pump 44 and valve 45 are passed to crystallizer 25.It is to be used for structure with filler load fibers suspension operation by what Fig. 1 described.Particularly use calcium carbonate, be affected the forming in the different phase of producing of fibrous suspension that produce.

In another kind of form of implementation kind, fibrous suspension is transported to a pipeline system that assembles with control valve 49,50 to load with calcium carbonate at device 48 (Fig. 2).Control valve 49 is mounted on the pipeline 51, is connected with a static mixer 52 by its this pipeline system.By valve 53 dilution water is imported static mixer.Control the inflow of calcium hydroxide suspension equally by another valve 55 of installing at pipeline 54.This provides adjusting by being equipped with device 56, and solid oxidation calcium or calcium hydroxide place water therein.Add entry by pipeline with valve 57 at this device for formulating 56.The suspension of preparation is sent into pipeline 55 with pump 58 in device for formulating 56.

Flow out and mixes with calcium hydroxide and the fibrous suspension that dilutes is delivered to pipeline 59 thus with valve 60 by blender 52.By pipeline 59 suspension is directly delivered to container 61 (crystallizer).This container is provided with valve 62,63 and links to each other with the material storaging tank 66 of carbon dioxide with the input carbon dioxide with the pipeline 65 of pump 64 by one.Thus carbon dioxide is sent into crystallizer 61, for make produce there required calcium hydroxide and carbon dioxide precipitation reaction with form calcium carbonate in the fiber of fibrous material as filler.Replace using blender 52 calcium hydroxides also can sneak into by raw material tank.

Pipeline 65 links to each other with a static mixer 68 by another valve 67, and it is used for making the fibrous substance suspension that flows out from crystallizer 61 add carbon dioxide again by a pipeline 70 of being furnished with valve 69.

Flow out fibrous suspension to blending tank 71 (fusion case) from blender 68, it is equipped with a rotor with complete blended fiber suspension.Flow out fibrous substance suspensions or, for example in the material feeding box of a concise device, handle by blending tank 71 directly to the material basin of paper machine or carry out further mechanical treatment.

In addition, by valve 50 and pipeline 73 fibrous substance suspension is delivered to blender 71, this suspension is adding calcium hydroxide not.

Also can a concise device 74 be installed at pipeline system in addition is used for by the additional concise fibrous substance suspension of process of lapping.By the pipeline 75 that pipeline 59 branches come out fibrous substance suspension is sent into this concise device.The fibrous substance suspension that will grind again from concise device 74 enters pipeline 70 and from there, as above-mentioned, enters material storaging tank by pipeline 76.

Consider in advance that in addition concise device 74 imports carbon dioxide with the static mixer 78 that links to each other with pipeline 75 by by a pipeline 77 of pipeline 65 branches from carbon dioxide-head tank 66.

In the structure that is used for the fibrous substance suspension preparation, container 74 is born additional process of lapping, creates a simple structure that is used for the fibrous material proportioner like this.Process of lapping is simultaneously as whipping process, so that make tosca in fiber by shear history.

Can have a filter 79 between blender 68 and blending tank 71, it is similar to filter 38, from wherein sending head tank back to the filtered fluid of calcium carbonate enrichment or being used for other bunkerage of prepared and diluted water or fibrous substance suspension.

Relevant bis table

1. pipeline system

2. control valve

3. control valve

4. pipeline

5. static mixer

6. valve

7. groove

8. pump

9. static mixer

10. valve

11. valve

12. pipeline

13. proportioner

14. pipeline

15. valve

16. pump

17. pipeline

18. valve

19. dehydrating threaded rod

20. pipeline

21. basin

22. pipeline

23. homogenizing screw rod

24. pipeline

25. container

26. valve

27. valve

28. pump

29. pipeline

30. carbon dioxide-basin

31. pipeline

32. valve

33. valve

34. static mixer

35. valve

36. pipeline

37. blending tank

38. filter

39. rotor

40. pipeline

41. pipeline

42. valve

43. pipeline

44. pump

45. valve

46.-

47.-

48. device

49. control valve

50. control valve

51. pipeline

52. blender

53. valve

54. pipeline

55. valve

56. proportioner

57. valve

58. pump

59. pipeline

60. valve

61. container

62. valve

63. valve

64. pump

65. pipeline

66. carbon dioxide basin

67. valve

68. blender

69. valve

70. pipeline

71. mixed storage tank

72. rotor

73. pipeline

74. concise device

75. pipeline

76. pipeline

77. pipeline

78. static mixer

79. filter

Claims

1. load the method for the fibrous substance suspension that contains cellulose fibre with calcium carbonate, have following processing step:

● the calcium hydroxide or the calcium oxide of liquid or dried forms are added in the fibrous substance suspension,

● the carbon dioxide of gaseous state is added in the fibrous substance suspension,

● use the carbon dioxide winnofil,

● milled fibre material suspension in loading procedure,

● in washing the fibre material suspension behind the crystallization process and/or before process of lapping and/or during process of lapping and/or behind process of lapping.

2. particularly by the method for claim 1, have following processing step with the fibrous substance suspension of calcium carbonate loading cellulose fiber:

● the calcium hydroxide or the calcium oxide of liquid or dried forms are added in the fibrous substance suspension liquid,

● use the carbon dioxide winnofil,

● washing the fibre material suspension before fibrous substance suspension being introduced the machine that the material trough installed in fibrous substance suspension flow direction downstream and/or introducing be used for reprocessing fibrous substance suspension.

3. particularly by the method with calcium carbonate load fibers material suspension of claim 1 and 2, have following processing step:

● introduce the filtered fluid that pressure setting (19,38,79) is used to extrude fibrous substance suspension,

● send back to small part filtrate and to be used to dissolve fibrous substance suspension in the operation.

4. by the method for claim 3, it is characterized in that

Filtrate sends back in the basin of inlet side, particularly raw material tank (7).

5. by the method for claim 3 or 4, it is characterized in that,

Calcium hydroxide to small part sends back in the operation with the dissolving fibrous material.

6. by the method for claim 5, it is characterized in that,

Be used for the dissolving of fibrous material in operation, pH value will maintain between 7～12, particularly between 8～12 at least.

7. by the method for one of aforesaid right requirement, it is characterized in that,

Using moisture fibrous material, particularly denseness as raw material is 0.1～20%, preferably the moisture paper material between 2%～8%.

8. by the method for one of aforesaid right requirement, it is characterized in that,

Calcium hydroxide is sneaked in the moisture fibrous material, particularly the paper fiber of solid contents between 0.01%～60% wherein.

9. by the method for one of aforesaid right requirement, it is characterized in that,

Calcium hydroxide is to mix with static mixer (9,16) or with storage tank.

10. by the method for one of above-mentioned claim, it is characterized in that,

Calcium hydroxide is at the scope internal reaction between 0.05～60 second particularly between 0.01～180 second.

11. the method by one of above-mentioned claim is characterized in that,

Dilution water is sneaked in the fibrous substance suspension, particularly before adding carbon dioxide and/or calcium hydroxide or calcium oxide, during or afterwards.

12. the method by one of above-mentioned claim is characterized in that,

Carbon dioxide is sneaked in the moist fibrous substance suspension.

13. the method by one of above-mentioned claim is characterized in that,

Paper siccative per ton uses the grinding energy between 0.1～300kwh.

14. the method by claim 13 is characterized in that,

The introducing of energy is to control by grinding technics.

15. the method by one of aforesaid right requirement is characterized in that,

Use static mixer, concise device (80), disperser and/or loosening device-FLPCC-reactor is as reactor, fibrous material content wherein, particularly paper content is between 0.01～15% at static mixer, and concise device and disperser are between 2～40%, particularly when LC-grinds between 2～8% and when HC-grinds between 20%～35%, and at loosening device-FLPCC-reactor between 15%～60%.

16. the method by one of above-mentioned claim is characterized in that,

To precipitating anti-use energy consumption, particularly between 0.5～4kwh/t, particularly when not adopting grinding technics at 0.3～8kwh/t.

17. the method by one of above-mentioned claim is characterized in that,

Technological temperature is between-15～120 ℃, particularly between 20～90 ℃.

18. the method by one of above-mentioned claim is characterized in that,

Form (rhombedrische) leg-of-mutton (Skalcnohedrische) and the spherulite of rhombus.

19. the method by claim 18 is characterized in that,

Crystal size is between 0.05～5 μ m, particularly between 0.3～3.5 μ m.

20. the method by one of aforesaid right requirement is characterized in that,

Adopt static and dynamic, the hybrid element of Zhuan Donging (68) particularly.

21. the method for one of above-mentioned claim is characterized in that,

This method is particularly carried out between 0～6bar at pressure limit 0～15bar.

22. the method by one of above-mentioned claim is characterized in that,

This method is particularly carried out between 6.5～9.5 between pH value 6～10.

23. the method by one of above-mentioned claim is characterized in that,

The time of the reaction of this method particularly carried out between 0.05～40 second between 0.01～180 second.

24. be used to implement device by claim 1～23 method, it is characterized in that,

At dehydrating threaded rod (19) an additional static mixer (9) is arranged before, fibrous substance suspension mixes with filtrate and/or calcium hydroxide suspension therein.

25. the device by claim 24 is characterized in that,

The filtrate of the fibrous substance suspension that obtains at dehydration ascarid bar (19) turns back to storage tank (7) by pipeline (20) or another one is used for the bunkerage that fibrous substance suspension is prepared.

26., it is characterized in that by claim 24 or 25

Additional static mixer (52), a washing the fibre material suspension therein arranged in that crystallizer (61) is preceding.

27. the device by claim 26 is characterized in that,

In crystallizer (25,61) back one additional wash mill (38,79) is installed and is used to clean fibrous substance suspension.

28., it is characterized in that by claim 26 or 27

An additional static mixer (52) arranged in that crystallizer (61) is preceding, wherein can return fibrous substance suspension.