WO2008056978A1

WO2008056978A1 - Apparatus for processing fibrous pulp material

Info

Publication number: WO2008056978A1
Application number: PCT/NL2007/050538
Authority: WO
Inventors: Johannes Cornelis Dekker; Harm Bouma; Franciscus Bernardus Maria Mulder
Original assignee: Agrotechnology And Food Innovations B.V.
Priority date: 2006-11-06
Filing date: 2007-11-05
Publication date: 2008-05-15

Abstract

The invention relates to an apparatus (1) for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising a drum (2) having a rotational axis (R), an inlet end (3), an outlet end (4) and an inner surface, a plurality of rolls (11) arranged in said drum with their rotational shafts substantially parallel to said rotational axis of said drum and defining nips between a surface of said rolls and said inner surface of said drum, driving means from revolving said drum and said rotational shafts of said rolls with respect to one another, an inlet (6) for introducing pulp adjacent to said inner surface of said drum at said inlet end of said drum, an outlet (7) for removing processed pulp adjacent to said inner surface of said drum at said outlet end of said drum, and an adjustment device for setting the width of said nips.

Description

Apparatus for processing fibrous pulp material

Background

The present invention relates to an apparatus for processing fibrous pulp material. In US-A-2.551.946 an apparatus for treating paper making fibers is disclosed which has a drum in which rolls are mounted. There rolls can be driven in such a way that they rotate about the rotational axis of the drum. Pulp material is made to travel repeatedly under the rolls, i.e. between the surface of the rolls and an inner surface of the drum.

In US-A-2.719.463 an apparatus for working or treating fibrous material, in particular for treating pulp for making paper, is disclosed which has a drum and two rolls inside the drum. The drum or cylindrical casing is entirely supported on the upper roll of the two rolls and is allowed to rotated or revolve with the driven upper roll. Pulp material is fed to the apparatus via an inlet at an end face of the drum, which inlet is arranged around a shaft of the upper roll and removed via an outlet at the opposite end face of the drum. Each of the two rolls has a grooved surface with grooves which extend in a longitudinal, spiralling way on the surface of said rolls. The grooves are at a slight angle with respect to the longitudinal direction of said rolls.

In DE 894 499 an apparatus for treating of processing fibrous material is disclosed which has a drum and rolls mounted inside said drum. In this apparatus, the drum is driven to rotate around its longitudinal axis and the rolls are pressed against the inner surface of said drum using springs. Neither an inlet or an outlet for the pulp are indicated. The rolls are arranged to co-rotate with the drum at the same speed as the drum, but this speed may be adjusted in such a way that the rolls rotate faster of slower than the drum. Furthermore, the rolls have circumferential grooves, perpendicular to the longitudinal axes of the rolls. In DE 959 345 an apparatus for treating pulp is disclosed, which has a drum.

Inside the drum, one or more rolls are provided which is pressed against the inner surface of the drum with adjustable pressure using spring force or centrifugal force. A roll is driven to rotate around its longitudinal axis. An inlet for the pulp is provided at one end face of the drum, and an outlet is provided at the opposite end face. The roll and the inner surface of the drum can have a different surface speed.

All these devices have room for improvement. In particular, control of various operational parameters before or during operation needs improvement.

Summary of the invention

An object of the invention is to allow independent control of several operational parameters before operation. Another object of the invention is to allow independent control of several operational parameters before operation.

Yet another object of the invention is to improve the flow of pulp through the apparatus.

According to a first aspect of the invention this is realized with an apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising:

- a drum having a rotational axis, en inlet end, an outlet end and an inner surface;

- a plurality of rolls arranged in said drum with their rotational shafts substantially parallel to said rotational axis of said drum and defining nips between a surface of said rolls and said inner surface of said drum;

- driving means from revolving said drum and said rotational shafts of said rolls with respect to one another;

- an inlet for introducing pulp adjacent to said inner surface of said drum at said inlet end of said drum; -an outlet for removing processed pulp adjacent to said inner surface of said drum at said outlet end of said drum, and

-an adjustment device for setting the width of said nips.

This provides the possibility of adjusting the width of the nips during processing of the pulp. Furthermore, it has become possible to accurately adjust the nip, and it is now possible to determine the width of the nips, making it possible to steer and control this parameter and to use this parameter to steer and control the process, for instance for reducing power consumption or milling time. In an embodiment of the apparatus according to the invention, the adjustment device is adapted for displacing the rotational shafts of said rolls radially with respect to said drum.

In an embodiment said adjustment device comprises a driving device, engaging said rotational shafts of said rolls. In an embodiment, said driving device comprises a transmission for transmitting motion of a driving unit, such as an electromotor or a hydraulic unit, into a displacement of the shafts of the rolls in radial direction. Thus, the apparatus can be enabled to actively adapt the width of the nips during processing, depending on process conditions. In an embodiment said adjustment device comprises a driving unit, a gearing coupled to said driving device and comprising gear wheels, and wherein said rotational shafts of said rolls are eccentrically mounted with respect to said gear wheels of said gearing.

In an embodiment said apparatus comprises a central shaft running through said drum, and wherein said adjustment device comprises a sun gear wheel, planet gear wheels engaging said sun gear wheel, and wherein said rotational shafts of said rolls are eccentrically mounted with respect to the rotational axes of said planet gear wheels. This construction is relatively simple and can handle larger force. In addition, a more accurate adjustment is possible. In an alternative embodiment, the shafts of the rolls are eccentrically mounted in planet wheels which engage a central sun wheel, in which the rotation of the sun wheel is transmitted to the planet wheels by means of friction.

In an embodiment said driving device comprises a first sleeve coaxially around one end of said central shaft and a second sleeve coaxially around the other end of said central shaft, wherein said drum is rotatably or revolvably mounted on said first and second sleeve.

In an embodiment said adjustment device is adapted for substantially simultaneously displacing both ends of the rotational shafts of said rolls. In an embodiment, said adjustment device comprises a driving device, two gearings coupled to said driving device and comprising gear wheels, with one gearing mounted near each end of said drum, and wherein both ends said rotational shafts of said rolls are eccentrically mounted with respect to gear wheels of said gearings. In a or further embodiment, said apparatus comprises a central shaft running through said drum, and said adjustment device comprises sleeves rotationally mounted on both ends of said central shaft, and transmission means coupling a driving unit to said shafts of said rolls. In an embodiment, a sun gear wheel is connected to each of said sleeves, and planet gear wheels coupled to both of said sun gear wheels, and wherein both ends of said rotational shafts of said rolls are eccentrically mounted on said planet gear wheels and mounted on said central shaft, and said driving device is operationally coupled to said central shaft for rotating said central shaft with respect to said sleeves. The shafts of the rolls are thus radially displaced via a rotational shift or adjustment of the central shaft. In an embodiment, the driving means for revolving the drum and rotational shafts of the rolls with respect to one another is arranged for revolving the drum about its rotational axis. In a further embodiment of this, the rotational shafts of the rolls are substantially static with respect to the frame in the revolving sense, i.e. compared to the revolving motion of the drum in operation.

The rolls furthermore can run free with respect to the inner surface of the drum in such a way that in operation the relative speed of the inner surface of the drum and the surface of the rolls is as small as possible, nearly zero.

In an embodiment said drum is bearing-coupled to said sleeve, and wherein preferably said apparatus comprises a main driving device which is operationally coupled to said drum for revolving said drum. In an embodiment said apparatus comprises a central shaft mounted on a frame, and wherein a first end of said central shaft is hollow and is coupled to said inlet and a second end of said central shaft is hollow and is coupled to said outlet, said first end of said hollow central shaft opens inside said drum, in particular at an inlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum, and , said second end of said hollow central shaft opens inside said drum, in particular at an outlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum. In an embodiment said first hollow part of said central shaft ends in a first end of said drum in at least one conduit which radially extends from said central shaft and ends between two rolls, debouching adjacent said inner surface of said drum. In an embodiment said second hollow part of said central shaft ends in a second end of said drum, and wherein at least one conduit which comprises an inlet end adjacent said inner surface of said drum and which extends radially from said inner surface of said drum between two rolls to said end of said second hollow part of said central shaft, wherein preferably said inlet end of said at least one conduit opens tangentially to said inner surface of said drum. In an embodiment, said at least one conduit opens as close as possible to said inner surface, for instance almost scraping against said inner surface of said drum for nearly scraping said pulp from said inner surface of said drum. In an embodiment said apparatus further comprising at least one guiding device positioned between two rolls comprising a plurality of guiding fins nearly touching said inner surface of said drum for in operation guiding said pulp from said inlet end of said drum to said outlet end of said drum, and a guiding fin adjacent said outlet end of said drum and nearly touching said inner surface of said drum oriented for guiding said pulp from said outlet end to said inlet end.

In an embodiment the surface said rolls comprise grooves, said grooves being at an angle with respect to the rotational axes of said rolls, preferably said grooves are at an angle of between 45 up to but smaller than 90 degrees with said rotational axes of said rolls, and furthermore in particular said grooves are spiralling grooves. In an embodiment, said groove spirals opposite to the direction in which the pulp passes the drum.

In an embodiment, the spiralling groove is a substantially top hat shaped groove. In an embodiment of the width of the bar, i.e. the substantially flat portion between grooves, is about 2-10 mm., preferably about 4-6 mm., specifically about 5 mm.

In an embodiment of the grooves of the rolls, the breadth of the grooves is about 2-12 mm., preferably about 4-6 mm., specifically about 5 mm.

In an embodiment of the grooves of the rolls, the depth of the grooves is about 2- 15 mm., preferably about 4-11 mm., specifically about 7 mm. In an embodiment, the angle of the grooves with respect to the rotational axis of a roll is about 80-89 degrees, preferably about 86-89 degrees. A roll with for instance about 5 mm. bar width and about 5 mm. groove breadth can be made with an angle of about 86-89 degrees. In this case, the defined angles covers both grooves of rolls, when mounted in the apparatus, which spiral in the direction of the inlet and grooves which spiral in the direction of the outlet.

The pitch of the spiralling groove can be about 10-400 mm, preferably about 10- 50 mm. In an embodiment, the rolls in the apparatus are substantially identical.

In an embodiment, the drum of the apparatus comprises sealings for substantially airtight sealing of said drum. In particular, the apparatus further comprises mean, such as a compressor, a cylinder or other container for pressurized gas, for supplying gas to the drum. This gas can be air, or another gass which can be beneficial for the process. This gas can be provided at a pressure which is above atmospheric pressure. In particular, the air or gas can be provided at a pressure of substantially the same magnitude as the pressure of the pulp during processing. This makes it possible to mill pulp almost without loss of pressure in the milling process. Thus, an additional pump for pumping the pulp to and through the apparatus may no longer be needed. The invention further relates to an apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising:

- driving means from revolving said inner surface of said drum and said rotational shafts of said rolls with respect to one another;

- an inlet for introducing pulp adjacent to said inner surface of said drum at said inlet end of said drum;

-an outlet for removing processed pulp adjacent to said inner surface of said drum at said outlet end of said drum, and wherein said apparatus comprises a central shaft onto which said drum is rotatably mounted and which is mounted on a frame, and wherein a first end of said central shaft is hollow and is coupled to said inlet and a second end of said central shaft is hollow and is coupled to said outlet, said first end of said hollow central shaft opens inside said drum, in particular at an inlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum, and , said second end of said hollow central shaft opens inside said drum, in particular at an outlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum. The invention further relates to an apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising:

-an outlet for removing processed pulp adjacent to said inner surface of said drum at said outlet end of said drum, and

- at least one guiding device positioned between two rolls comprising a plurality of guiding fins touching said inner surface of said drum for in operation guiding said pulp from said inlet end of said drum to said outlet end of said drum, and a guiding fin adjacent said outlet end of said drum and touching said inner surface of said drum oriented for guiding said pulp from said outlet end to said inlet end.

The invention further relates to an apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising:

- a plurality of rolls arranged in said drum with their rotational shafts substantially parallel to said rotational axis of said drum and defining nips between a surface of said rolls and said inner surface of said drum; - driving means from revolving said inner surface of said drum and said rotational shafts of said rolls with respect to one another;

- an inlet for introducing pulp adjacent to said inner surface of said drum at said inlet end of said drum; -an outlet for removing processed pulp adjacent to said inner surface of said drum at said outlet end of said drum, and wherein the surface said rolls comprise grooves, said grooves being at an angle with respect to the rotational axes of said rolls, preferably said grooves are at an angle of between 45 up to but smaller than 90 degrees with said rotational axes of said rolls, and furthermore in particular said grooves are spiralling grooves.

The invention further relates to a method for processing pulp, wherein an apparatus according to any one of the preceding claims is used, wherein the energy used by said apparatus is determined, and based upon the energy consumption, in particular the energy per amount of pulp, the width of the nip is adjusted, in particular the width is adjusted for maintaining the energy per unit time at a preset value.

The various aspects and features discussed in this patent and the dependent claims can be combined in order to provide additional advantageous advantages. Furthermore, these features can be subject of a divisional application. The invention further pertains to a device comprising one or more of the characterising features described in the description and/or shown in the attached drawings, and to a method comprising one or more of the characterising features described in the description and/or shown in the attached drawings.

Description of the drawings

The invention will be further elucidated referring to an embodiment of an apparatus of the invention, in which is shown in the drawing: Fig. 1 a side view of an embodiment of an apparatus according to the current invention; fig. 2 the apparatus of fig. 1 in II-II cross section; fig. 3 the apparatus of fig. 1 in III-III cross section; fig. 4 the apparatus of fig. 1 in IV-IV cross section; fig. 5 the apparatus of fig. 1 in perspective view with open drum; fig. 6 the apparatus of fig. 1 in side view; fig. 7 the apparatus of fig. 1 in longitudinal cross section along line I-I of fig. 6; fig. 7a an enlarged detail of fig. 7; fig. 8 a roll for the apparatus of fig. 1 in cross section; fig. 9 the roll of fig. 8 in perspective view.

Detailed description of embodiments

In the figures l-7a various views of an apparatus 1 for processing pulp material according to the invention are shown. The apparatus 1 has a drum 2 with an input end 3 and an output end 4. In this embodiment, the drum is driven to rotate or revolve about longitudinal axis R by means of an electromotor 5 which is operationally coupled to the drum via a belt 9. The electromotor 5 has a control unit 18.

The apparatus 1 has an inlet 6 for pulp to be processed, an outlet 7 for processed pulp, and is mounted on a frame 8.

In fig. 2 the apparatus 1 of figure 1 is shown in cross section II-II. Drum 2 has an inner surface 10 and rolls 11 having a surface 12. Between the inner surface 10 of drum 2 and the surface of each roll 11 a nip is defined. Between several of the rolls 11, a scraper is installed which has a beam 14 and several scraper bodies 15 which scrape the surface 10 of drum 2. The drum 2 has two parts 16 and 17 which can be removed for easy access to the interior of apparatus 1.

The central shaft 13, which will be discussed later, is shown in cross section. In fig. 3 the apparatus of fig. 1 is shown in cross section along line III-III. In this cross-section, a part of an adjustment device for setting or adjusting the width of the nip. The adjustment device comprises a sun gear 21 and planet gears 22 on shafts 23 and engaging the sun gear 21. Sun gear 21 is in a rotatably fixed way mounted on a (hollow) shaft 20. In fig. 4 the apparatus of fig. 1 is shown in cross section along line IV-IV. In this cross-section the outlet for the processed pulp is shown. The inlet part of output end 7 of hollow shaft 13 opens inside the drum 2 and is coupled to conduits 30, here two oppositely extending conduits 30. These conduits extend between two rolls 11 and 11' and open in mouth parts 31 which scrape the inner surface 10 of drum 2. In order to properly accommodate the conduits 30, rolls 11' are shortened a little.

In figure 5 the apparatus of figure 1 is shown is perspective view, with one halve of the drum (nr 16 in fig. 2) removed. In this drawing, a drive unit for the adjustment device is shown. It comprises a (servo) electromotor 51 which is coupled via gearing 52 to the hollow shaft 13. The motor 51 can rotate hollow shaft 13 via gearing 52. Hollow shaft 13 is rotatably mounted on frame 8.

Figure 5 furthermore shows the bar 14 of the scraper with the scraping bodies 15. All these scraping bodies 15 are inclined to one direction in order to guide the pulp from the inlet end 3 of drum 2 to the outlet end 4 of drum 2. On the bar 14 there is a further scraper 50 which is located near the outlet end 4 of drum 2 and which is inclined in a direction opposite to the direction of the scraping bodies 15. In operation, scraper 50 prevents pulp from actually reaching the outlet end of the drum and it directs the pulp into mouth part 31. The scraping bodies can be mounted to scrape the surface, or be mounted to be free from the surface, almost touching the surface.

In fig. 6 a side view of the apparatus of fig. 1 is shown in side view seen on the outlet 7 of hollow shaft 13. Fig. 7 is a longitudinal cross section along line I-I of fig. 6. For a better understanding of the adjustment device, a part of fig. 7 has been enlarged as fig. 7a. Starting from the inlet 6, the central shaft 13 in this cross section comprises an inlet shaft part 70, which is rotatably coupled to a further shaft part 71 which ends in inlet end part 63. The inlet end part 63 is connected to a central shaft part 73. Inlet end part 63 has an opening 90 which gives access to conduit 91.

Starting from outlet 7 at the opposite end of the central shaft 13, it comprises an inlet shaft part 75, rotatably coupled to a further shaft part 74 which ends in outlet end part 64. this outlet end part 64 is also connected to the central shaft part 73. Shaft parts

70, 71, 63, 73, 64, 74 and 75 thus form the hollow central shaft 13.

Further shaft part 71 of the central shaft 13 is in a rotatably fixed way coupled to a gear wheel of gearing 52 of the adjustment device. Coaxially around further shaft part

71, a sleeve part 72 is rotatably provided. Sleeve part 72 is fixed to the frame 8 and extends in the drum 2. The part of sleeve part 72 extending in drum 2 is provided with the sun gear wheel 21. The sun gear wheel 21 is in a rotatably fixed way coupled on sleeve part 72, i.e. sun gear wheel 21 rotates together with sleeve part 72. In a rotatably fixed way disk 62 is coupled to further shaft part 71, i.e., when central shaft 13 rotates, disk 62 rotates with it. Disk 62 at its circumference rotatably holds bushes 79 in which shaft ends of rolls 11 are borne. These shaft ends of rolls 11, 11' are positioned eccentrically in the bushes 79. Bushes 79 are coupled to planet gear wheels 22 in such a way that the rotational axis 23 of a gear wheel 22 is in line with the rotational axis of a bush 79, and that the bush 79 is coupled to the gear wheel 22 in a rotationally fixed way.

The construction near the inlet end of the drum 2 described in the previous paragraph is substantially identical to the construction at the outlet side of the drum 2. Similar parts there have the same number as the parts at the inlet side of drum 2. Both sides of the adjustment device are coupled to each other via shaft 13, which driven both disks 62.

Coaxially on sleeve part 72 a bush 78 is borne (on bearing 61) onto which an end face of the drum is fixed. The bush 78 is connected to wheel 76 onto which belt 9 runs. The opposite end face of the drum 2 is fixed onto bush 78' which is borne on sleeve part 77. In this way, the drum can revolve about its rotational axis R on sleeve parts 72 and 77.

The drum 2 is mounted onto sleeves 71, 74 in an nearly airtight manner. The bush 78 (and 78' at the other end of the drum 2) has sealings. Furthermore, sleeves 72 and 77 and hollow shaft parts 71, 74 are well sealed. Thus, almost no pressure is lost and very little energy is needed to pass the pulp through the apparatus 1.

Drum 2 can furthermore be coupled to a source of pressurized air (not shown) which provides air (or another gas) under pressure to the interior of drum 2. Preferably, the pressure is of the same magnitude as, preferably almost equal to, the inlet pressure of the pulp. In that way, the pulp can pass the apparatus 1 almost without loss of pressure. Thus, not additional pump or power is needed to pass the pulp through the apparatus.

In operation, the drum is revolved or rotated using motor 5 and the rolls are stationary. Pulp is pumped via inlet 6 through the central hollow shaft 13 until it encounters inlet end part 63. There, its direction is changed and through (here two) conduits similar to the outlet conduits 30 of fig. 4 the pulp is directed to a position between two rolls 11'. There, the conduits in this embodiment open in the rotational direction of the inner surface of drum 2, similar to the mouth parts 31 of the outlet. The pulp spirals along the inner surface of drum 2, guided by means of scraper bodies 15, towards the outlet end of drum 2, and the pulp is being milled between the inner surface of drum 2 and the rolls 11, 11'. Via scraper 50 the direction of the pulp is changed a little and it enters mouth parts 31 and through its dynamic pressure it is pressed through conduits 30 and via the flow diverter 65 in outlet end part 64 it enters shaft part 74, and via shaft part 75 it exits the apparatus 1. Scraper bodies 15 and scraper 50 thus function as a doctor blade.

Before of during processing, the width of the nips between the inner surface 10 of drum 2 and the surfaces 12 of rolls 11, 11' can be adjusted. To that end, servo electromotor 51 is activated. This turns or rotates, via the final gear wheel of gearing 52 connected to the shaft part 71, shaft part 71 and thus disk 62. The rotational position of sleeve 72 and thus sun gear 21 remain fixed with respect to frame 8. This makes the engaging planet gear wheels 22 rotate and thus bushes 79. Rotation of bushes 79 in disk 62 makes the shaft 80 of the rolls 11, 11' effectively displace in radial direction with respect to the inner surface 10 of drum 2, as these shafts 80 are eccentric with respect to the bushes 79, and thus the width of the nips change.

The rolls 11 are shown in detail in figs 8 and 9. In longitudinal cross section view in fig. 8, it can be seem that the surface 12 of roll 11 is substantially flat (82) and has spiralling grooves 82. Roll 11 has a rotational axis 60 en shaft ends 80.

Several groove patterns on the rolls have been tested. The results are summarized in the table below.

From this comparison can be concluded that:

- Roll 4 gives the best energy-paper strength ratio - Roll 3 versus roll 4 shows that the transverse grooves (almost 90°) of roll 4 are better than the longitudinal grooves of roll 4.

- Comparing rolls 1,2 and 4 shows that a groove width of about 5 mm and a bar width of about 5 mm. seems to be optimal. Other possibilities which were explored are: bar width 7 mm. with groove width 5 mm., and bar width 3 mm. with groove width 5 mm;

This leads to the following values possible values for the profile of the rolls: Bar width 2-10 mm., preferably about 5 mm. Groove breadth 2-12 mm., preferably about 5 mm. groove depth 2-15 mm., preferably 4-11 mm., specifically about 7 mm.

A roll with for instance 5 mm. bar width and 5 mm. groove breadth can be made with the following angles:

- no pitch, i.e. an angle of 90°, but this configuration is abrasive to the inner surface of the drum; - single: pitch 10 mm, angle about 88.6°, which is a preferred angle;

-double: pitch 20 mm, angle about 87.1°, which is more expensive to manufacture;

- 40-fold: pitch 400 mm, angle about 45°: gives about the same result as almost 90° (almost no pitch). It will also be obvious after the above description and drawings are included to illustrate some embodiments of the invention, and not to limit the scope of protection. Starting from this disclosure, many more embodiments will be evident to a skilled person which are within the scope of protection and the essence of this invention and which are obvious combinations of prior art techniques and the disclosure of this patent.

Claims

1. Apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising:

- a plurality of rolls arranged in said drum with their rotational shafts substantially parallel to said rotational axis of said drum and defining nips between a surface of said rolls and said inner surface of said drum; - driving means from revolving said drum and said rotational shafts of said rolls with respect to one another;

-an adjustment device for setting the width of said nips.

2. Apparatus according to claim 1, wherein said adjustment device is adapted for displacing the rotational shafts of said rolls radially with respect to said drum.

3. Apparatus according to claim 1 or 2, wherein said adjustment device comprises a driving device, engaging said rotational shafts of said rolls.

4. Apparatus according to claim 1, 2 or 3, wherein said adjustment device comprises a driving device, comprising a driving unit, and a gearing coupled to said driving device, said gearing comprising gear wheels, and wherein said rotational shafts of said rolls being eccentrically mounted with respect to said gear wheels of said gearing.

5. apparatus according to claim 4, wherein said apparatus comprises a central shaft running through said drum, and wherein said adjustment device comprises a sun gear wheel, planet gear wheels engaging said sun gear wheel, and wherein said rotational shafts of said rolls are eccentrically mounted with respect to the rotational axes of said planet gear wheels.

6. apparatus according to claim 5, wherein said driving device comprises a first sleeve coaxially around one end of said central shaft and a second sleeve coaxially around the other end of said central shaft, wherein said drum is rotatably mounted on said first and second sleeve.

7. Apparatus according to claims 2-6, wherein said adjustment device is adapted for simultaneously displacing both ends of the rotational shafts of said rolls, preferably said adjustment device comprises a driving device, comprising a driving unit and two gearings coupled to said driving device and comprising gear wheels, and one gearing mounted near each end of said drum, and wherein both ends said rotational shafts of said rolls are eccentrically mounted with respect to gear wheels of said gearings, in particular said apparatus comprises a central shaft running through said drum, and said adjustment device comprises sleeves rotationally mounted on both ends of said central shaft, a sun gear wheel connected to each of said sleeves, and planet gear wheels coupled to both of said sun gear wheels, and wherein both ends of said rotational shafts of said rolls are eccentrically mounted on said planet gear wheels and mounted on said central shaft, and said driving device is operationally coupled to said central shaft for rotating said central shaft with respect to said sleeves.

8. Apparatus according to claim 7, wherein said drum is bearing-coupled to said sleeve, and wherein preferably said apparatus comprises a main driving device which is operationally coupled to said drum for revolving said drum.

9. Apparatus according to any one of the preceding claims, wherein said apparatus comprises a central shaft mounted on a frame, and wherein a first end of said central shaft is hollow and is coupled to said inlet and a second end of said central shaft is hollow and is coupled to said outlet, said first end of said hollow central shaft opens inside said drum, in particular at an inlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum, and , said second end of said hollow central shaft opens inside said drum, in particular at an outlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum.

10. Apparatus according to claim 9, wherein said first hollow part of said central shaft ends in a first end of said drum in at least one conduit which radially extends from said central shaft and debouches adjacent said inner surface of said drum, preferably between two rolls.

11. Apparatus according to claim 10, wherein said second hollow part of said central shaft ends in a second end of said drum, and wherein at least one conduit which comprises an inlet end adjacent said inner surface of said drum and which extends radially from said inner surface of said drum to said end of said second hollow part of said central shaft, wherein preferably said inlet end of said at least one conduit opens tangentially to said inner surface of said drum, preferably scrapingly against said inner surface of said drum for scraping said pulp from said inner surface of said drum.

12. Apparatus according to any one of said preceding claims, further comprising at least one guiding device positioned between two rolls comprising a plurality of guiding fins almost touching said inner surface of said drum for in operation guiding said pulp from said inlet end of said drum to said outlet end of said drum, and a guiding fin adjacent said outlet end of said drum and almost touching said inner surface of said drum oriented for guiding said pulp from said outlet end to said inlet end.

13. Apparatus according to any one of the preceding claims, wherein the surface said rolls comprise grooves, said grooves being at an angle with respect to the rotational axes of said rolls, preferably said grooves are at an angle of between 45 up to but smaller than 90 degrees with said rotational axes of said rolls, and furthermore in particular said grooves are spiralling grooves.

14. Apparatus according to any one of the preceding claims, wherein said drum comprises sealings for substantially airtight sealing of said drum, in particular said apparatus further comprises mean, such as a compressor, for supplying gas, in particular air, at a pressure above atmospheric pressure, in particular air or gas at a pressure of substantially the same magnitude as the pressure of the pulp during processing, to said drum.

15. Apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising:

-an outlet for removing processed pulp adjacent to said inner surface of said drum at said outlet end of said drum, and wherein said apparatus comprises a central shaft onto which said drum is rotatably mounted and which is mounted on a frame, and wherein a first end of said central shaft is hollow and is coupled to said inlet and a second end of said central shaft is hollow and is coupled to said outlet, said first end of said hollow central shaft opens inside said drum, in particular at an inlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum, and , said second end of said hollow central shaft opens inside said drum, in particular at an outlet end of said drum, into at least one conduit extending from said hollow shaft to said inner surface of said drum between two rolls and opening near the inner surface of said drum.

16. Apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising:

- a drum having a rotational axis, en inlet end, an outlet end and an inner surface; - a plurality of rolls arranged in said drum with their rotational shafts substantially parallel to said rotational axis of said drum and defining nips between a surface of said rolls and said inner surface of said drum; - driving means from revolving said inner surface of said drum and said rotational shafts of said rolls with respect to one another;

17. Apparatus for processing a flow of pulp comprising fibrous material, in particular pulp comprising cellulose fibres for making paper, said apparatus comprising: - a drum having a rotational axis, en inlet end, an outlet end and an inner surface;

-an outlet for removing processed pulp adjacent to said inner surface of said drum at said outlet end of said drum, and wherein the surface said rolls comprise grooves, said grooves being at an angle with respect to the rotational axes of said rolls, preferably said grooves are at an angle of between 45 up to but smaller than 90 degrees with said rotational axes of said rolls, and furthermore in particular said grooves are spiralling grooves.

18. Method for processing pulp, wherein an apparatus according to any one of the preceding claims is used, wherein the energy used by said apparatus is determined, and based upon the energy consumption, in particular the energy per amount of pulp, the width of the nip is adjusted, in particular the width is adjusted for maintaining the energy per unit time at a preset value.

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