DE2732140A1 - SOOT PELLETING DEVICE - Google Patents

Description

Dr. F. Zumstein Sr. - Dr. E. Asstrann Dr. R. Koenigsberger Dipl.-Phys. R. Holzbauer - Dipl.-Ing. F. Klingseisen - Dr. F. Zumstein jun.

PATENTANWÄLTE 273214 (3

β MUNICH 2.

BRÄUHAUSSTRASSE 4

TEUHFON: COLLECTIVE NO. 225341 TELEGRAMS: ZUMPAT TELEX 529979

6 / Li

Germ. 0 25 US 0 24 164 ..

Phillips Petroleum Company Bartlesville, OkI., USA

Carbon black pelletizer

The invention relates to pelletizing carbon black. On the one hand, the invention is concerned with feeding in a pelletizing fluid into the pelletizer for wet pelletizing of carbon black and on the other hand with a carbon black pelletizer, in which a pin provided shaft is rotatably mounted in a housing.

Soot, which is produced by the pyrolytic decomposition of hydrocarbons obtained is collected from a vapor or smoke or smoke containing soot by filtration. Here receives one soot in flaky form and the handling of the so obtained To facilitate the use of the carbon black in terms of transport and packaging as well as the intended use of the carbon black,

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soot is pelletized.

A wide variety of pelletizing devices and methods for pelletizing carbon black are known. A very Common pelletizing apparatus has a cylindrical housing and a pin shaft mounted in the housing is rotatably arranged. Soot and pelletizing fluid are introduced into the space between the shaft through openings in the housing and the housing initiated. The pinned shaft rotates and soot pellets are formed.

Furthermore, a carbon black pelletizing device has also been proposed which has a hollow shaft and is in the form of a conduit which is provided with open ends Has pins which are in communication with the internal cavity of the shaft. This allows the fluid material are injected at high speeds against the housing wall to cause the formation and build-up of a soot cake to prevent. However, the structure and construction of such a pelletizing device is expensive and complicated, so that the production costs for such a pelletizing device are to be set correspondingly high. Farther the replacement of such hollow-shaped pins in fluid connection with a hollow shaft is very cumbersome and laborious. Furthermore, the hollow-shaped pins are arranged along the entire length of the shaft and can therefore not can be used to feed in the entire amount of pelletizing liquid, since it is important for pelletizing is that the flaky carbon black and the pelletizing liquid in appropriately suitable form at the beginning of the pelletizing process relative proportions must be present, i.e. at the upstream end of the pelletizer.

There is thus a need to have available a carbon black pelletizing apparatus in which the pelletizing liquid can be fed such that rapid and effective mixing of the dry flaky carbon black with the fed Liquid is achieved at which the feed

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and mixing at the upstream portion of the carbon black pelletizer possible are.

When operating known carbon black pelletizing devices for wet pelletizing of carbon black and a pelletizing solution in an approximate weight ratio of 1: 1 some occur Problems. A main problem is that it is advantageous to use more stable or rigid pins, than was previously possible. Such rigid or stable pins can withstand the forces and wear in the pelletizing devices withstand better. Another difficulty with pelletizers lies in the fact that that the wet soot mass through the pins on or near the inner surface of the housing of the pelletizer strong mechanical Is exposed to stress. The soot mass on or near the shaft is much slower Movement of the pins suspended. The advantage now is that the entire wet soot mass has approximately the same mechanical effect suspend in the pelletizer to produce uniform pellets.

The main problem in the production of pellets from carbon black, in particular in such pelletizing devices, determines the pellet size distribution as well as the shape and shape of the pellets. Ideally, the pellets produced should all be spheres of the same diameter. However, this can be done economically hardly realize. However, there is a need to have a pelletizing device available that can carry the pellets can produce a very even, i.e. very small or narrow, pellet size distribution. The invention aims aims to provide a carbon black pelletizing device with a means for feeding pelletizing liquid which rapid and thorough mixing of the pelletizing liquid with the flaky soot immediately after it has been fed in into the pelletizer.

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The carbon black pelletizing device should preferably be designed in such a way that small and uniform carbon black pellets are produced can.

In particular, a soot pelletizing device should be designed in such a way that short and stable or rigid pins are provided are.

A pelletizing device should preferably be designed in such a way that the moist or wet soot mass is removed during the pelletizing process is subject to a "uniform pelletizing effect.

In particular, the invention is concerned with a pelletizing device, at which the power to drive, in particular to drive the shaft with pins, is essentially remains constant during the entire operation without significant load fluctuations occurring.

A pelletizing device should preferably be designed in such a way that the pellets obtained have a narrow particle size distribution range exhibit.

In particular, the pelletizing device should be designed so that it is made of known materials and known per se Way can be built.

The invention is described below with reference to the attached Drawing explained in more detail on preferred embodiments.

Figures 1 and 2 are cross-sectional views through a pelletizer according to the invention;

Fig. 3 is a detailed illustration of the pelletizer;

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Fig. 4 is a diagram illustrating, for example, the arrangement of the pens; and

FIG. 5 shows a further diagram to illustrate the pin arrangement on the shaft when it is developed in a plane.

In connection with the exemplary embodiments, it has been found that the introduction of pelletizing liquid through openings in a hollow shaft provided with pins, which is rotatably arranged in the housing of a pelletizing device and via a line arrangement connected to a source of pelletizing liquid for efficient and rapid mixing Pelletizing liquid fed in via the shaft with pins leads to the dry soot.

According to a preferred embodiment of the invention A carbon black pelletizing device has been created which has a cylindrically shaped elongated housing. Inside this Housing, a hollow shaft is arranged coaxially and rotatably. Several pins are attached to this shaft, essentially extend radially from the shaft to the housing. One or more openings are provided in the shaft, the inner one Connect the cavity of the shaft with the annular space between the shaft and the housing. The openings are in places on the Shaft provided on which no pins are attached, so that the pelletizing liquid fed through these openings can leave the hollow shaft unhindered.

According to another embodiment of the invention, the hollow shaft connected to a source of pelletizing liquid such that at least a major part of the pelletizing liquid during operation through the openings in the pelletizing device entry. The entire amount of pelletizing liquid is preferably fed into the pelletizing device through the openings fed and brought into contact with the soot.

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- JB -

A preferred development of the invention deals with the arrangement of the openings. In this embodiment all openings for introducing the pelletizing liquid on the shaft upstream of or near the upstream end of the portion of the shaft arranged on which pins are provided. In this arrangement, a mixture of Pelletizing liquid and soot ensured immediately at the beginning of the pelletizing process. Preferably, therefore, are the openings in the shaft provided only in the area which is in the vicinity of the upstream pins of the shaft.

To the volume of the pelletizing liquid present in the hollow shaft To reduce, preferably two parallel plates are near the upstream pins in the hollow shaft arranged, these plates being substantially perpendicular to the shaft axis. The two parallel plates lie at a small distance from one another and touch the interior of the hollow shaft with a fluid-tight seal. The openings in the shaft in this preferred embodiment are arranged so that the interior of the shaft, which is through the two Plates is limited, is connected to the annulus between the shaft and the housing. Line arrangements for introduction a pelletizing liquid in the interior of the shaft between the two plates are provided, and these line arrangements are connected to one of these plates.

Furthermore, according to the invention, a carbon black pelletizing device can be constructed in such a way that it has a housing with an essentially cylindrical inner surface. A shaft is arranged coaxially and rotatably within this housing. A plurality of pins are provided on this shaft which run approximately radially to almost the inner surface. The pen density over the entire wavelength is approximately constant. According to the invention, the pins are arranged on the shaft such that no more than about 3% of the pins in it are axial

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And not more than 10% in the same azimuthal position. The main feature of the invention is to be seen in the fact that a very even distribution of the pins is provided, see above that the carbon black starting material to be pelletized a smooth, uniform and predominantly constant action by the Pins throughout the pelletizing process and along the pined shaft.

The following are intended to explain the general Designations are defined in more detail. These designations relate in particular to the description of the pen distribution along a cylinder. Every mathematical point on a certain cylinder can be determined by its axial position and is in front of · » lying case by the axial position, e.g. in cm (in.) from the beginning of the cylinder and by the azimuthal position, e.g. in degrees, starting from a reference line at 0 ° to 360 °. These two coordinates, in particular the axial position and the azimuthal position are generally sufficient to reflect the geometric arrangement of the pins in the pelletizing device according to the invention to determine, since in the description the position of the pins with respect to each other on a certain cylinder is assigned so that the third of the cylindrical coordinates, in particular the radial position, is approximately constant or is the same for all pens.

When relative positions between pins are given below, these refer to the mathematical center of these pins. Since the actual distance between two pins is smallest on the shaft and greatest at the free pin ends, the geometry of the pins in the description below is sometimes given in terms of an imaginary cylinder that is coaxial with the shaft and the housing at the same distance of the shaft and the housing. This imaginary cylinder accordingly has a radius of 0.5 x (R ₁ + R ₂ ), where R _{1 is} the radius of the shaft and R _{2 is} the radius of the housing. The designation

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"Trace or line of a pen" refers to the intersection of the central axis of the pen with the imaginary one Cylinder.

The distance between the centers of the pins is referred to below as the distance marked between the pins. This distance is measured on the corresponding cylinder surface. The distance between the pens can be thought of as a straight line in the drawing if the pen cylinder, e.g. the imaginary cylinder with the pen tracks, is developed in one plane.

The term "same axial position" of the pins relates to the fact that the centers of these pins are located within a ring around the shaft which is an axial length of approximately 1.5 pin diameters. Similarly, the term "same azimuthal location of the pins" refers to the fact that the centers of these pins along the shaft are within an elongated straight strip of width of approximately two pin diameters are arranged. A main feature of the invention can be seen in the fact that only a very minor one Percentage of the pins of the type defined above have the same axial position (the pins are not in washers arranged), and that only a very small number of the pins have the same azimuthal position (the pins are not arranged in a comb shape).

The fact that the pen density, i.e. the number of pens per unit area, was pinned over the whole Wave is approximately constant can be expressed in another way in terms of the minimum distance between the pins on the one hand and the maximum area with no pegs on the other hand. When the minimum distance between two pins with r is assumed, the maximum distribution of the pins is such that no circle with a radius larger ' as R, where R is approximately 0.58 r to 0.8 r, on the imaginary cylinder developed in a plane

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that does not contain at least one trace of the center of the pen. A circle with the radius R can also be referred to as the maximum empty circle or the maximum possible empty circle (ie that does not contain a trace of a pen center). Each larger circle contains at least one trace of the center of the pen. Each group of values of r and R within the specified definition ranges determine the minimum and maximum spacing of the pins. The radius r of a circle that can be drawn around each pen trace without encompassing another pen trace is in the range of about 2f ( ^R i ^{+ R} 2 ^ ^{to un} 6 ^efänr Tj (R ₁ + R ₂ ). This relationship expresses the minimum pin center distance as a function of the diameter of the imaginary cylinder. The minimum pin distance is preferably approximately 6 to 12 pin diameters. Thus, a relationship between the minimum pin distance and the pin diameter is obtained.

In a preferred embodiment of a pelletizing device there are approximately 80 to 200 pins on the shaft. These pins are preferably each on different axial ones Arranged in layers, and the distance between axially adjacent pins is smaller than the diameter of the pins. The axial distance between axially adjacent pins can range from approximately 0.5 to 0.9 pin diameter. It should be noted that axially adjacent pins are generally not those pins that are closest to one another but that there are two pins that are closest only with respect to the axial direction.

In the preferred embodiment of a pelletizing device according to the invention, the pins are arranged in such a way that one or more of the following absolute range specifications characterize the pin geometry in more detail. The pen density over the entire imaginary cylinder is in a range of 1/50 to 1/20 per 6.45 cm ² (1/50 to 1/20 pens / sq.in.). The radius

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of the imaginary cylinder is 12 to 46 cm (0.4 to 1.5 ft.). The axial length of the shaft, which is studded, is approximately 76 to 152 cm (30 to 60 in.). Of the Shaft diameter is 18 to 61 cm (0.6 to 2 ft.), The diameter of the inner surface of the case is 30 to 122 cm (1 to 4 ft.).

The pins are attached to the shaft in such a way that the pin density is approximately constant over the entire shaft, and the Pins are preferably arranged in such a geometric pattern that is more closely referred to as "imperfect or incomplete spiral "can be identified. The pins are along the shaft in at least one such imperfect or incomplete. gaps in spiral or helical lines. The incomplete spiral or helical line can be negative describe in more detail by stating that it is not a normal or incomplete helical line. If the Pins are arranged on a normal or ordinary helix, the ratio of the axial distance between two axially adjacent pins to the angular or azimuthal distance of these pins constant. This can be done through the following Print out the equation:

0.

t,

where with ρ the slope of the helix, with a the azimuthal one Angular distance in degrees between adjacent pins along the helical line and with d the axial distance of two axially adjacent pins are indicated on the helical line. In an ordinary helix the value of is ρ is a constant. According to a preferred embodiment of the In accordance with the invention, the pins are arranged on a patchy or defective helical line, i.e. a line that goes around the shaft

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goes in approximately helical form with the important exception that the slope p, as in the above Equation, is not a constant along the line, but extends a few times along this incomplete line Helix changes. In a preferred embodiment of an incomplete helical line, they all point axially adjacent lying pins on the same axial distance t between each other, and the azimuthal angular distance a between axially adjacent lying pins changes several times along the patchy helix. It is preferably the Change of the azimuthal angular distance a along the broken helical line by a periodic change. This periodic Change is dimensioned according to a preferred embodiment such that the azimuthal distance a between axially adjacent lying pins periodically changes between values along the broken helix. Thus the azimuthal angular distance along the patchy helix a first value al for a first number of pins, then a second value a2 for a second number of pins, then a first value a1 for a third number of pins, the is the same as that for the first number of pins, etc. The difference between a1 and a2 is preferably a little smaller Fraction of 360 °, e.g. 1/10 to 1/20 of 360 °. A preferred one Embodiment for changing the azimuthal distance of axially adjacent pins can thereby describe that the azimuthal distance of three consecutive pins is 90 °, and this is followed by a distance of 112 ° and 30 minutes for a pen, this sequence being repeated periodically.

The ratio of the inside diameter D of the pelletizer housing to the outer diameter d of the shaft on which the pins are attached, lies according to a preferred embodiment of the invention in a range from 1.3 to 2. This means that the shaft diameter is very large and the

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The space in which the pelleting takes place is an annulus, which remains free between the shaft and the housing. This embodiment allows the use of short and stable or rigid pins, and the diameter of these pins can Compared to pelleting devices, which have the same throughput, but a shaft with a significantly smaller diameter compared to the inside diameter of the housing have to be reduced considerably. In addition, the soot mass and the soot pellets and the pelletizing liquid subjected to a very uniform pelletizing effect.

According to a preferred embodiment of the invention, the inner diameter D of the housing is related to the length L of the Section of the shaft which is provided with pins, in a ratio of D / L, which is preferably in a range of 0.5: 1 to 2: 1. The ratio of the length of the pins to the diameter of the pins is preferably in a range from 5: 1 to 30: 1. This ratio is preferably 10: 1.

The horizontally arranged soot pelletizer has a soot inlet at the upstream end and an outlet for the Pellets at the downstream end. Furthermore, the carbon black pelletizing device with a steady or continuous screw conveyor at the upstream end of the shaft below of the inlet for the soot, so that the soot introduced into the housing in the direction of the pelletizing section or the section of the shaft provided with pins, which is moved in the axial direction of the continuous screw conveyor connects. The pitch of such a screw is generally a multiple of the mean pitch of the patchy helix as previously defined.

Further embodiments of preferred pelleting devices are characterized in that two or more of the above specified characteristics in connection with the three main aspects

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of the invention are realized.

Fig. 1 shows a longitudinal sectional view through a pelletizing device according to the invention and FIG. 2 shows a longitudinal cross-sectional view through the pelletizing device shown in FIG lines 2-2. Inside the housing 1, very close to an upstream end plate 2 and a downstream end plate 2, a shaft 4 is rotatably arranged. Several pins 5 are welded onto the shaft 4. An inlet 6 for introduction of flaky soot and an outlet 7 for pulling off the soot pelvis are provided. The outlet 7 is formed by that one excludes a segment of large azimuthal dimension from the circular housing. A motor 8 is for driving the shaft 4 provided with pins is provided. On the upstream End of the pinned shaft 4 and below the inlet 6 is the pinned shaft as a continuously conveying screw conveyor 9 is formed.

The shaft 4 essentially comprises a hollow cylinder 41, the is closed at both ends by end plates 42, only the downstream end plate being shown in the drawing. The end plates are in turn connected to rod-shaped members 43 and 44. These rod-shaped links are in bearings 21 and 31 rotatably mounted. The rod-shaped member 43 has. an axially extending channel 46 to provide a pelletizing flow · to let through. At the end facing the hollow cylinder 41, the rod-shaped member 43 is provided with a thin tube 48, which is in communication with the channel 46. This thin tube 48 is in turn connected to a first plate 52. The first plate 52 and a second plate 54 are perpendicular arranged to the longitudinal axis of the pelletizing device. The distance between the two plates is small and on the order of magnitude of 5 cm (2 "). The two plates 52 and 54 are of this type within the hollow cylinder 41 with a fluid-tight seal arranged that a chamber 53 is formed between them.

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The thin tube 48 connects the channel 46 and the chamber 53. In the area between the two plates 52 and 54 are four Openings 55 are drilled in the cylinder 41 at locations where no pins 5 are provided. The rod-shaped member 43 and the channel 46 are connected via a fluid-tight connection 62 to a source 64 for pelletizing liquid.

The housing 1 of the pelletizing device is supported on two supports 10 and 11.

The pins 5, which are arranged along the hollow cylinder 51 according to an incomplete helical line, which will be explained in more detail in the following, have pointed edges at their free ends, which during the rotational movement of the shaft 4 along the housing 1 while maintaining a small A distance of for example 6 to 3 mm (1/4 to 1/8 ") from the housing can be moved like a knife. The individual pins 5 are welded to the cylinder 41. As mentioned, the pins 5 are along the shaft 4, in particular longitudinally the outside of the hollow cylinder "41", arranged in a pattern of a defective or incomplete spiral or helical line. To explain this in more detail, the pins are numbered from 1 to 109. These digits are indicated in FIGS. Each pin is the same axial distance from the pin which is axially adjacent to that pin on the patchy helix, and it should be expressly stated that one is axially adjacent ender pin is not the closest pin. For example, the axial distance between pins 1 and 2, between pins 2 and 3, between pins 3 and 4, etc. is each 9.5 mm (3/8 "). The azimuthal angular distance between these adjacent pins along the gap helix is not for all the pins of the same. As appears in particular from Figs. 2 and 4 can be found, be at the first three spacings between the pins 1,2,3 and ₍₄ 90 °. the azimuthal distance between the pins 4 and 5 However, it is 112 ° 30. Follow pin 5

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three pins 6, 7 and 8 at a distance of 90 °. Then the azimuthal distance between the pins 8 and 9 is again 112 ° 30 ', as can be seen from FIGS. 2 and 4. The result of the arrangement of pins along a broken helical line can also be found in FIG. Most of the pens shown in the figure are 15 different Groups of pens. With respect to pins 49 and 68 and 17 and 36 and 81 and 100, however, 19 pins are spaced apart. It should be noted that these pins are not adjacent in the sense of the above definition, since e.g. a few turns ^ of the broken helix between these pins 34 and 49 lie.

Fig. 4 shows the pin position on a patchy helical line that has been developed into a plane. One not patchy or ordinary helix would consist of a series of pins connected by a straight line are. In Figure 4, the pin layers are not in a straight line, but along a number of segments of straight lines Lines. This deviation of the pin arrangement from the ideal helix is referred to as the "patchy helix".

In Fig. 5, the actual pattern of the pins on the shaft is shown developed in a plane. The number of pen marks is the same as that of the other figures. As can be seen from FIG. 5, there are axially adjacent pins numbered consecutively. Thus, for example, pin 16 is axially adjacent to pin 15 and pin 17, while neither pin 15 nor pin 17 is the closest pin to the pin 16 is. The trace diagram in Fig. 5 has an imaginary cylinder equidistant from the hollow shaft 4 and the housing 1 is on.

When operating the pelletizer it becomes more flaky

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Soot is introduced into the annular space between the shaft 4 and the housing 1 via the inlet 6. By the rotary movement of the screw 9, the soot is advanced in the direction of the pelletizing section of the shaft 4, the. is provided with pins 5. A pelletizing liquid is fed into the same annular space between the shaft 4 and the housing 1 via the four openings 55 in the hollow cylinder 41, which are offset azimuthally by 90 ° and are arranged in the same axial position. The pelletizing liquid can be ordinary water or water which contains additives such as ENT, molasses, lignosulfonate or oil-water emulsions, etc. The rotation of the shaft 4 moves the mixture of soot and pelletizing liquid to the left in Fig. 1 from the upstream point to the downstream point, and during this movement moist soot pellets are formed. These moist soot pellets are drawn off via outlet 7. The moist carbon black pellets are then processed, for example dried, and then packaged for transport.

In the following an embodiment with dimensions of a carbon black pelletizing device according to the invention is shown:

Length of Hollow Cylinder 41 6 ft. 10 in. (2.08 cm)

Outside diameter d of shaft 4:

Wall thickness of the hollow cylinder 41:

axial length of the zone of the screw conveyor 9:

Pitch of the screw:

Inner diameter D of the housing 1:

Diameter of the pins 5:

Distance between pin end and housing:

Pen length:

axial distances from axially adjacent pins:

0.61 cm (2 ft. O in.) 1.3 cm (1/2 in.) 0.69 m (2 ft. 3 in.) 15th cm (6 in.) 91.8 cm (3 ft.1 / 8 in.) 1.6 cm (5/8 in.) 6-3 mm (1 / 4-1 / 8 in.) 14.9 cm (5-7 / 8 in.) 9.5 mm (3/8 in.)

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The shaft 4 with the pins 5 rotates in this pelletizing device in basic operation at about 200-450 rpm. The throughput of a pelletizer of this size amounts to 1812 kg / h (4000 lbs / hr) soot or approximately 3624 kg / h (8000 lbs./hr) wet soot pellets.

The following embodiment shows the effect of the arrangement of the pins along a broken helical line deviating from an arrangement along a complete one Helical line with regard to pellet size and size distribution.

example

In a laboratory-scale pelletizer having a structure as shown in Figures 1, 2 and 3, flaky carbon black and water containing 196 molasses were pelletized in a weight ratio of approximately 1: 1. The shaft rotated at about 400 rpm. The pellets obtained were dried and analyzed for pellet size distribution according to the ASTM 1511 method.

For comparison, the same amount of carbon black and water was used to make pellets in a pelletizer processed, which differed from the pelletizing device shown in FIGS. 1,2 and 3 in that the Pins 5 not along a broken helical line (see in particular FIG. 4), but along a non-broken one Helical lines were arranged so that both the axial distance between the pins and the azimuthal angular distance between adjacent pins were the same for the entire helix. The axial distance between adjacent pins was the same as the patchy helix, 9.5 mm (3/8 in.), and the azimuthal distance between adjacent pins was 90 °. The created pellets

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were then also dried and analyzed according to the ASTM 1511 method to determine the pellet size distribution. The results of these comparative tests are compiled in the table below.

Tabel

Pellet size distribution (ASTM D 1511)

(ASTM D 1511)

With (sieve 10) 2.00 mm with (sieve 18) 1.00 ram

With (sieve 35) 0.50 mm

With (60 sieve) 0.25 mm

With (sieve 120) 0.125 mm

In the trough ^

Total weight %

In the range (-18 + 60) -1mm + 0.25

Pin arrangement 7.6 Wt%. Wt%
usually screw-gaps
benline screws
line 16.4 17.4 64.6 58.6 4.2 12.0 3.8 4.0 3.4 3.4 100.0 4.6 68.8 100.0 K), 25 mm 16

The results obtained show that when carbon black is pelletized with a pelletizer, the pins of the pelletizer open a broken helical line of the type mentioned were arranged, 68.8 wt .-% of dry carbon black pellets in the sieve area from -18 + 60 positions. In the case of pellets, which in contrast here - (- 1mm + 0.25mm)

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- yes -

.22,

to have been manufactured in a pelletizing device, the pins of which were arranged on an ordinary helical line, was only 16 wt .- # of dry pellets within the stated sieve range. 76% by weight of carbon black in this pelletizer incurred, in which the pins were arranged along an ordinary helical line, were larger than the required screen particle size range. The results also show that the pellets, which with the help of a Pelletizing devices were made in which the pins were arranged along a broken helical line, smaller than * those pellets that are in a pelletizer which differed only in that from the pelletizing device according to the invention the pins were geometrically arranged in the form of an ordinary helix. A pellet size range of -1mm + 0.25 mm (-18 + 60) sieve size refers to pellets that have a sieve with a mesh size of 1.00 mm (18 mesh sieve) pass, but remain in a sieve with a clear mesh size of 0.25 mm (60 mesh sieve). Bigger ones Sieve numbers than the usual refer to smaller openings in the sieve than with smaller sieve numbers.

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Claims (7)

1732U0 claims 1. Soot pelletizing device with a housing in which a shaft is coaxially and rotatably arranged and a cylindrical shaft Inner surface is provided with a means for introducing of pelletizing fluid into the housing, means for withdrawing soot pellets and having a plurality of pins, which are evenly distributed on the shaft, with the pin density approximately for the entire length of the Shaft equals \ ind with the pins roughly radially after extending outside of the shaft in close proximity to the inner surface of the housing, characterized in that that the pins (5) on the shaft (A) along at least one incomplete screw or Spiral line are arranged. 2. Pelletizing device according to claim 1, characterized in that the incomplete helical line is determined thereby is that the position of the pins on the shaft (4) corresponds approximately to that of a spiral line, that but the slope of axially adjacent pins, determined by the equation "_ 360 ° . . changes several times along the broken helical line, where ρ is the pitch of axially adjacent pins, a the azimuthal one Angular distance in degrees between axially adjacent pins along the broken helical line and t the is the axial distance between these axially adjacent pins. 709883/1 107 ^ ί ORIGINAL INSPECTED 3. Pelletizing device according to claim 2, characterized in that all pins (5) have the same axial distance t have between axially adjacent pins, and that the azimuthal angular distance between adjacent Pins several times along the-patchy helical line changes. 4. Pelleting device according to claim 3, characterized in that the azimuthal angular distance between adjacent Pins (5) periodically changes along the broken helical line. 5. Pelletizing device according to claim 4, characterized in that the azimuthal angular distance along the gaps Helical line between axially adjacent pins has a first value for a first number of consecutive ones Pins, has a second value for a second number of consecutive pins, this sequence being repeated periodically. 6. Pelletizing device according to one of the preceding claims, wherein the housing has an inner diameter (D) and the shaft (4) has an outer diameter (d), characterized in that the ratio of the inner diameter (D) of the housing (1) to the outer diameter (d) of the shaft (4) is within the range from 1.3s1 to 2: 1. 7. Pelletizing device according to one of the preceding claims, characterized in that the shaft (4) is hollow is that one or more openings (55) in the shaft (4) the cavity in the shaft (4) with the annular space connects between the shaft (4) and the housing (1) that the openings (5) are arranged at points on the shaft, on which no pins (5) are attached to the shaft, that a source (64) for pelletizing liquid via the line 709883/1107 Z732U0 processing arrangement is connected to the hollow shaft (4) in such a way that that at least a large part of the pelletizing liquid is introduced into the pelletizing device via the openings (55) is that two parallel plates (52,54) on the inside of the hollow shaft (4) on a stable nearby attached to the upstream pins (5) of the shaft (4) are that the plates (52,54) are arranged approximately parallel to each other and perpendicular to the axis of the housing (1) are arranged and connected along their periphery with a fluid-tight seal with the interior of the shaft (4), that the openings (55) in the shaft (4) are arranged so that they the interior of the shaft (4) through the two plates (52,54) is limited, connects to the annular space between the shaft (4) and the housing (1), and that a line arrangement is provided which a connection between the interior of the shaft (4) through the two plates (52,54) is limited, and a shaft (64) for pelletizing liquid produces. 709883/1107