DE102018004280A1 - Dispergierring for Devulkanisieren of waste rubber - Google Patents

Abstract

According to the invention, a depolymerization or devulcanization of waste rubber takes place in the planetary roller extruder.

Description

The invention relates to a dispersing ring for the devulcanization of waste rubber or for breaking the crosslinking of other elastomers. Rubber consists of natural rubber and / or artificially produced elastomers whose molecules have undergone crosslinking. Among others, sulfur-carbon compounds and sulfur-sulfur compounds between the molecular chains are known.

Sulfur crosslinking is probably the most common form of crosslinking in rubber. There are other forms of crosslinking that can be broken thermally and mechanically. The term devulcanization used here also includes, beyond sulfur-vulcanized rubber, the other crosslinked elastomers whose compounds can be broken up mechanically and thermally.

It is also spoken of cross-links of the molecular chains. Crosslinking drastically changes the material properties.

This relates in particular to the strength, elasticity and heat load capacity.

Predominantly rubber is used in the vehicle industry. The load capacity of vehicle tires is legendary.

Depending on the running kilometer of the tires results in a state of wear, which is measured by how much the profile of the tires is worn.

If the profile has fallen below a certain thickness, a tire change must be made.

It fall on old tires or old rubber.

Although there are various proposals for the chemical treatment of waste rubber, but the effort is so high that so far it is hardly used. Rather, waste rubber is preferably supplied to the combustion. The cement industry has proven to be a large buyer. There, the waste rubber in the rotary kilns is mitverbrannt. The cement rotary kiln has a long combustion section, so that unburned gases are burned. A burden on the environment from unburned gases of waste tire combustion is thus excluded.

However, the cement industry usually requires a waste disposal contribution for waste tire combustion.

The disposal of used tires is also no longer considered timely.

Therefore, efforts have been made for a long time to the recycling of rubber and elastomers.

There are different ways.

After DE60004885T2 are used to devulcanize cured (crosslinked) elastomers and rubber modifiers. These modifiers consist entirely or partially of adipic acid or oxalic acid. Furthermore, find additives that consist of sulfur, zinc oxide and stearic acid.

In the DE 909041 are provided as modifiers Edeleanuextrakte that are derived from petroleum processing. These are, for example, kerosene, nitrobenzene, furfurol, phenol, dichlorodiethyl ether,
The DE 60008279T2 provides amine compounds as devulcanizing / modifying agents.

The DE60215210T2 provides aromatic oil, naphthenic oil or paraffinic oil as a devulcanizing agent.

The 60306089T2 provides 2-butanol and carbon dioxide as devulcanizing agents.

Also the DE60120804T2 provides modifier. However, the oil is extracted from the recyclate itself.

The modifiers have the disadvantage that the modifiers remain wholly or partly in the recyclate and limit the usability of the recyclate very strong.

Devulcanization without chemical agents is also known. Microwaves and ultrasonic waves are preferably used. The waves create a strong mechanical stress on the rubber and elastomers, which are intended to disrupt the molecular chains. The mechanical load can be supplemented by the application of heat or by high vapor pressure.

Nevertheless, this type of devulcanization is considered insufficient, cf. for example the DE60120804T2 ,

Another way to devulcanization offers the WO2011 / 091966 , Crosslinked waste rubber and crosslinked elastomers, which are at least partially destructible mechanically and / or thermally, are devulcanized by means of an extruder. Especially Used rubber and elastomers whose crosslinking is based on a sulfur compound are to be devulcanized. The sulfur is released by mechanical and thermal stress and separated from the rubber or elastomers.

A planetary roller extruder is used.

Previously it was already known to cause a mechanical load with single-screw extruders and twin-screw extruders, can break through the molecular scaffolds. A corresponding prior art is in the DE60120804T2 as well as in the DE69329245T2 as well as in the DE69724239T2 described.

In planetary roller extruders, a much smaller mechanical load on the molecular frameworks is seen compared with a twin-screw extruder.

Although the planetary roller extruders are addressed in some pamphlets as a possible extruder variant, planetary roller extruder had hitherto been found in production facilities for the recycling of rubber and elastomers no input. The low expectation of the mechanical stress of molecular chains by planetary roller extruder corresponds to the fact that some references to the use of planetary roller extruders for the regeneration of rubber are at the same time connected with the reference to the addition of devulcanization agents described above. The Devulkanisierungsmittel have the disadvantage that they must be removed again. This is preferably done by degassing.

The residues of the devulcanizing agents which remain despite degassing greatly weaken the quality of the product produced.

The WO2011 / 091966 builds with dispersing rings for devulcanization an increased mechanical effect in planetary roller extruders. This allows at least a reduction of Moduzifierungsmittel. With the dispersing rings, the passage cross section for the rubber or elastomer treated in the extruder is reduced more than by a stop ring. Typically, thrust rings have an inner diameter that is slightly smaller than the diameter of the orbit on which move the center axes of the planetary spindles in their orbit.

In contrast, the inner diameter of the proposed dispersing ring is according to WO2011 / 091966 preferably at least 10%, preferably at least 20% and even more preferably at least 30% of the dimension of the associated planetary spindles smaller than the above-described diameter of the trajectory of the planetary spindle centers / center axes in their circulation.

The reduction can go so far that the dispersing surrounded the central spindle on the necessary game for the rotation of the central spindle out only with a small gap.

The reduction of the passage cross-section can even go so far that the dispersing ring engages in a groove of the central spindle.

In this case, the dispersing ring, for example, even only a gap of a few millimeters, in the extreme case of, for example, a millimeter, to the tooth base for the passage of rubber and elastomers can be left open.

It may be advantageous to incorporate the groove by a small amount, for example by the measure of one millimeter, on the tooth base of the teeth on the central spindle also in the central spindle. Such engaging in the groove of the central spindle rings are preferably made of several parts, so that the rings around the central spindle and in the groove can be set cross-together when the planetary roller extruder or planetary roller module is prepared for mounting the dispersion ring.

Preferably, the method is used for the treatment of waste rubber, which is exempt from metallic reinforcing inserts. Metallic reinforcing inserts occur especially on used tires. These are predominantly steel inserts, which hold the vehicle tires in the desired shape.

For the separation of rubber and metal, various methods are suitable.

Alternatively, the waste rubber is strongly cooled and crushed in the highly cooled state in a mill. When chilled, comminution becomes easier because the compliance of rubber decreases. The colder the rubber, the easier the shredding becomes.

After WO2011 / 091966 Rubber and elastomers are used as chips in the extruder. The mean chip diameter is preferably 5 to 40 mm, more preferably 15 to 30 mm.

In planetary roller extruder, the temperature of the material to be treated can be adjusted very well, because the material to be treated or rubber and elastomers is rolled over a large area and thin layers. This happens in accordance with the speed of the central spindle many times per minute. This affects the Planetary roller extruder as a large-area heat exchanger. Single-screw extruders and twin-screw extruders of comparable size have a comparatively small heat exchanger surface.

The planetary roller extruders have a centrally arranged, driven central spindle. The central spindle is usually provided externally with an involute toothing.

There are other types of gears as well. The involute toothing usually has a 45 degree skew of the teeth. There are also different tooth sizes. It is distinguished by tooth modules.

The central spindle is surrounded by a housing which has an internal toothing. In contemporary planetary roller extruders, the housing is internally provided with a bushing on which the internal toothing is found.

The internal toothing has the same tooth module as the external toothing on the central spindle.

Between the housing and the central spindle several planetary spindle are arranged uniformly on the circumference of the central spindle. The planetary spindles have an outer toothing with the same module as the central spindle and the housing toothing. The planetary spindles mesh with the central spindle and the internal teeth of the housing.

The rotating planetary spindles slide in the conveying direction at the front of a sliding ring or thrust ring, so that their orbit is determined in the axial direction. For further details of conventional planetary roller extruders, reference is made, for example, to the following references:

DE 102009019846 . DE 102009013839 . DE102008063036 . DE 102008018686 . DE 102007058174 . DE102007050466 . DE 102007041486 . DE 102007040645 ,

The feed material is rolled thin-layered in the planetary roller extruder between the intermeshing teeth. This creates a strong kneading effect on the waste rubber. Due to the kneading effect, heat is carried into the waste rubber.

The kneading effect can be influenced by different numbers and / or different design of the planetary spindles.

The number of planetary spindles is preferably at least 5, more preferably at least 6 , The larger the diameter of the central spindle, the more planetary spindles are usually provided in a module / section. Thus, for example, for larger sizes without further notice 24 and more spindles are used.

The planetary spindles may be formed, for example, as normal spindles, as hedgehog spindles or Noppenspindeln, as shown in the DE 10 2004 048 440 or in the US 7476416 are described. The normal spindles has one from one end to the other end of the same toothing. This gearing is original planetary gear teeth and is also referred to as standard gearing. All other gear types are considered special gears.

The hedgehog spindle builds on the standard spindle. At intervals in the hedgehog spindles annular circumferential recesses are incorporated into the teeth, so that in a lateral view of a spindle a meandering contour is visible.

The knob spindle also builds on a standard spindle. However, the spindle is provided after the normal toothing with an opposite toothing, which crosses the normal toothing. That is, in the teeth of the normal teeth are cut with the opposing teeth gaps of specific shape and sequence. The teeth remaining from the normal teeth show a knobbed shape. Due to the gaps / interruptions in the hedgehog spindle and the nubs spindle reduces the conveying effect of the planetary spindles, while the kneading action increases. In addition, the kneading operation with the knobs differs from the kneading operation with the normal spindle and the heddle spindle.

The references to the hedgehog spindles and nubble spindles describe further useful details of planetary roller extruders suitable for devulcanization.

The temperature of the material to be treated is brought in the planetary roller extruder by supplying heat or by cooling to a desired level for devulcanization.

This level is after the WO2011 / 091966 between 250 and 350 degrees Celsius, preferably between 250 and 300 degrees Celsius.

The kneading effect and heating effect is maintained for a period of 1 to 4 minutes, preferably 1.5 to 3 minutes. This duration corresponds to the residence time in the planetary roller extruder.

When kneading and heating the used rubber in the planetary roller extruder, the sulfur Compound blasted. The sulfur goes into a gaseous state. The gas is sucked off. At the extruder this is called degassing.

The exact determination of the material-dependent respectively correct kneading effect and temperature can be achieved by changing the cycle time and changing the temperature in a few experiments based on the test results.

With proper devulcanization, a fuzzy material without appreciable strength is produced after the corresponding treatment duration / length of stay of rubber and elastomers.

If the temperature is too high, the material to be treated / used visually shows the overheating, for example as a caking.

If the temperature is too low, the cross-linking will not be sufficiently removed; the discharged material, while flexible, will at least partially show its strength.

The planetary roller extruder is particularly suitable for the desired temperature control of waste rubber, if the housing has a socket on the inside in a known manner, which is provided on the central spindle side with the internal teeth described and is provided on the outside with a same normal toothing or other teeth. The bush is preferably shrunk into the housing. For this purpose, the bushing is cooled, so that the diameter is reduced sufficiently to be pushed into the housing. When reheated, the socket expands and the socket sits firmly in the housing.

The housing can also be shrunk onto the socket. Then the housing is heated and expands the housing, so that the socket can be pushed into the housing. After cooling, the housing encloses the socket firmly.

Both during a shrinking operation as well as during the other shrinking operation, the housing closes the gears of the external toothing on the socket. As a result, these passages can be used as channels for the passage of tempering.

The channels are preferably interconnected by an annular channel at the housing ends. The one annular channel is provided on the inlet side and connected to a supply line. The other channel is provided on the outlet side and connected to a drain line. Both lines are part of a temperature control. As tempering used in devulcanization oil.

The oil is pumped through the channels.

Depending on the oil temperature causes a cooling or heating.

Depending on the material properties of the waste rubber, an extruder can be used whose length is sufficient to carry out the entire devulcanization in an extruder. That is, the extruder then has a length in which the entire desired residence time can be represented.

Preferably, however, find extruder application, which are composed of mutually aligned modules / sections. Each module has its own housing and planetary spindles and its own stop ring.

Preferably, a common central spindle is provided for all mutually aligned modules / sections.

The modules / sections optionally have all or part of a length of less than or equal to 800mm, preferably less than or equal to 600mm and even more preferably less than or equal to 500mm.

Smaller lengths of individual or all modules / sections can be used to adapt to different temperature requirements if each section is provided with its own temperature control.

In addition, the temperature control on a longer extruder module / extruder section can also be subdivided into different sections which lie one behind the other in the axial direction.

However, module lengths / section lengths of more than 1000 mm, for example 1400 mm, can also be used. The greater the length of the planetary roller extruder sections / planetary roller extruder modules, the more advantageous it is if a plurality of temperatures in the axial direction of the sections / modules are arranged one behind the other at one section / module.

The larger the extruder diameter, the larger the throughput (amount per unit of time) usually becomes. At the same time, an extension of the residence time of rubber and elastomers in the extruder, for example, by a larger extruder length may be required.

With the modular design / section design opened on planetary roller extruder and the possibility of changing the kneading effect by changing the teeth or by installing modules with different teeth.

As far as the same modules are already provided, a change in the kneading effect and cycle time can be achieved by replacing the Plenetspindeln or by reducing the number of planetary spindles in hindsight.

This involves a serious practical advantage when changing the input material.

In this sense, spindles with normal spindles and / or with hedgehog spindles can be combined. The nubs spindles are the one extreme for the processing of rubber in the extruder, the effect of hedgehog spindles and normal spindles deviates from it. If it turns out that the cycle time is too long in the above sense, single or multiple stud spindles can be exchanged for hedgehog spindles or normal spindles. Optionally, transport spindles are also used to shorten the transit time, as used in the EP702739 are described. This means that single or multiple stud spindles are replaced by transport spindles.

The transport spindles also build on the normal spindles. In this case, one or more teeth are machined out of the spindle after the normal toothing of a spindle, so that the number of teeth is reduced.

Favorable in the processing of rubber or the like, a different length of the planetary spindles, so that the fed into a planetary roller module material is taken gently and not abruptly total of the teeth.

The application of the after WO2011 / 091966 The proposed method has led to a successful devulcanization of waste rubber with smaller sizes of planetary roller extruders. The system used is composed of a filling part and various planetary roller modules.

The object of the invention has been found to improve devulcanization, in particular to increase the economics of devulcanization with a planetary roller extruder.

This is achieved according to the invention with the features of the main claim. The subclaims describe preferred embodiments.

The invention has recognized that, however, considerable problems can arise in a planetary roller extruder of larger design, which can lead to corresponding interruption of operation. This is especially true for ring constructions that form the thrust ring and / or the dispersing ring. The invention provides an overheating hazard in the region of the rings. Particularly in the area of the thrust rings, due to the friction between the planetary spindles and the thrust rings, a particularly high energy input occurs. Overheating can occur if the heat can not be dissipated quickly enough over the above-described cooling of the planetary roller extruder sections / modules.

In planetary roller extruder sections / modules of small size, for example, a size of 150mm (derived from the pitch circle diameter of the internal teeth of the socket of the housing) malfunction due to overheating are low.

In planetary roller extruder sections / modules of larger size, for example a planetary roller extruder section / module of a size of 300 or 400 and more, another situation exists. For example, much more overheating may be caused by the planetary spindles because the planetary spindles slide along the run-up ring at such planetary roller extruder sections / modules of much greater pressure. This larger pressure leads to a proportional increase in the friction between the thrust ring and the planetary spindles.

Overheating leads to caking on the overheated surfaces as well as damage to the material to be used. The caking narrow the passage gap on the rings and accelerate and increase the overheating. or make the process unstable.

In the first development step, the vulnerable surfaces of the rings are provided with a coating that is material-repellent in certain areas. At low baking temperatures, this may be a plastic coating, for example a Teflon coating.

At high temperatures, a wear-reducing ceramic coating is provided instead of the plastic coating.

In a second development step, an additional cooling of the rings is provided beyond the above-described general cooling of the planetary roller extruder section / module.

With sole cooling of the stop ring, a closed cooling channel is preferably provided in the stop ring. To produce a closed cooling channel in the thrust ring of the thrust ring of two annular parts can be put together, of which one part has a U-shaped cross-section and the other part forms a cover with which the cavity of the U-shaped Cross-section is closed. Preferably, both parts are welded together, so that a closed annular space is formed. The annulus has an inlet and a drain for Temperierungsmittel. The inlet and the outlet are formed by bores and connected lines.

The holes for the line connection can be diametrically opposite each other on the outer circumference of the stop ring. Then the tempering agent distributed in the annulus of the run-up ring.

The line connections may also be adjacent to each other when forced by a wall between two line terminals, the temperature control, to flow in a large arc through the cooling channel. The wall forms a closure which prevents short-circuit flow between the supply line and the discharge line.

• -der Anlaufring mit der einen Seite in eine Aufnahmebohrung am Flansch des zu einem Planetwalzenextruderabschnitt/Modul gehörigen Gehäuses liegt und
• -der Anlaufring mit der anderen Seite in der gegenüber liegenden Aufnahmebohrung am Flansch des zu dem benachbarten Planetwalzenextruderabschnitt/Modul gehörigen Gehäuses liegt
• -und zwischen beiden Flanschen so viel Abstand besteht, daß die Leitungen für die Zuführung und Abführung des Temperierungsmittels zwischen den Flanschen angeordnet werden können.

The thrust ring with the connected lines can be easily in the joint between two
Mount planetary roller extruder sections / planetary roller extruder modules, as long as

• -the thrust ring is located with one side in a receiving bore on the flange of belonging to a planetary roller extruder section / module housing and
• -the thrust ring is located with the other side in the opposite receiving bore on the flange of belonging to the adjacent planetary roller extruder section / module housing
• and there is so much space between the two flanges that the conduits for the supply and discharge of the tempering means can be arranged between the flanges.

With sufficiently thick flanges and a small distance of the flanges and recesses for the lines can be provided in a flange or two flanges.

When using the dispersing ring described above, a constructive summary of the dispersing rings with the starting rings preferably takes place. The dispersing rings are offset relative to the starting rings so that the planetary spindles can not slide on the dispersing rings.

In the ring construction, there may be various cooling channels for cooling the sliding surfaces for the planetary spindles and for cooling the contact surfaces with the feed in the dispersing area. Preferably, a common cooling channel is provided.

If the inner diameter is chosen smaller than the outer diameter of the central spindle, then the dispersing rings engage in a groove in the shell of the central spindle. In that case, a multi-part formation of the dispersing rings is advantageous. Due to the multi-parting the dispersing rings can be put together in the groove of the central spindle. This allows mounting of the dispersing rings on the pre-assembled central spindle.

The multi-part design, however, complicates the cooling because leaks may occur at the separation points / joints of the Dispergierringteile that interfere with the operation and affect the quality.

According to the invention, an inlay is then provided in each cooling channel of the ring construction. The inlay prevents leaks.

As inlay is a copper tube, which is bent according to the cooling channel. Between the Leitrungsanschlüssen the tube is interrupted. As a result, the copper pipe can easily be bent up for mounting, so that it can be pushed over the central spindle. The tube cross section is optionally flattened. This makes it easier to bend the tube. According to the pipe cross-section of the cooling channel is designed. The tube then completely lines the cooling channel or rests against the inside of the cooling channel over its entire surface. This ensures a good heat transfer from the ring construction to the inlay and bridges over as joints of the parts forming the dispersing ring.

• -Winkelprofile, die zu einem Kastenprofil zusammen gesetzt werden
• -ein Z-Profil mit einem Winkelprofil, wobei das entstehende Kastenprofil einen Schenkel aufweist, der in die axiale Richtung oder in radialer Richtung nach außen weist. Der Schenkel kann dabei eine Zentrierungshilfe bilden.
• -zwei U-förmige Profile, die zusammen ein Kastenprofil bilden, das zwei Schenkel besitzt, die in eine axiale Richung ragen.
• -ein U-förmiges Profil und ein Winkelprofil, die zusammen ein Kastenprofil bilden, das einen Schenkel besitzt, derin die axiale Richtung weist.
• -im Querschnitt unregelmäßige Profile
• -Profile, die zusammen einen Kühlkanal bilden, aber zusätzlich mit Schenkeln versehen sind, die in axiale Richtung und/oder in radiale Richtung nach außen weisen
• -Profile, die zusammen einen Kühlkanal bilden und darüber hinaus ganz oder teilweise den Anlaufring bilden
• -Profile, die zusammen einen Kühlkanal bilden und ganz oder teilweise einen Anschluß an den Anlaufring bilden.

Instead of a dispersing ring part with a U-shaped cross section, other cross sections for forming a cooling channel may also be used, for example

• Angle profiles that are put together to a box profile
• a Z-profile with an angle profile, wherein the resulting box profile has a leg which faces in the axial direction or in the radial direction to the outside. The leg can form a centering aid.
• two U-shaped profiles which together form a box profile having two legs which project in an axial direction.
• a U-shaped profile and an angle profile, which together form a box profile having a leg facing in the axial direction.
• - in profile irregular profiles
• - Profiles which together form a cooling channel, but are additionally provided with legs which point in the axial direction and / or in the radial direction to the outside
• -Profile, which together form a cooling channel and also form part or all of the run-up ring
• -Profile, which together form a cooling channel and form part or all of a connection to the stop ring.

Instead of copper, any other metal / metal alloy with good thermal conductivity can be used for the inlay in the cooling channel.

The tempering agent / coolant is optionally compressed air. Alternatively, a water / compressed air mixture is used. The water is added to the compressed air immediately before entering the inlay in fine drops, which evaporate immediately in the inlay and cause intensive cooling. The fine drop shape is created by spraying the water over appropriately fine nozzles.

As described in the earlier application, it may be advantageous to arrange several dispersing rings one behind the other in a system. Preferably, this is done in each case in the context of a common ring construction described above with a stop ring. Then two or more planetary roller extruder sections / modules are provided, the thrust ring is connected in a common construction with a dispersing ring.

Incidentally, the passage gap is selected on a dispersing ring depending on the particular nature of the material to be used. For powdery feed a very narrow gap and long gap is selected, which necessarily leads to the desired deformation and associated mechanical stress. The same applies to fine-grained feedstock. With coarse material also a relatively large and short gap leads to the desired deformation and associated mechanical stress. The aim is to process as coarse material as possible. This relieves the processing of waste rubber for processing in the planetary roller extruder. That is, the waste rubber is only brought into a coarse grain by the provided, for example, shredding and / or grinding. This is associated with less work, effort and expense than shredding and grinding into a fine grain. The savings compared to a powder form become extreme.

After passing the first dispersing ring and machining in the associated planetary roller extruder section, the nature of the feedstock changes. Rubber and elastomers become more flexible. This is taken into account when choosing the next dispersing ring. In the following, one speaks of a gap width and gap length of the dispersion rings. This means the opening between the dispersing ring and the central spindle. This opening is an annular gap.

There are various factors influencing the dimensioning of the annular gap, in particular the nature of the material to be used, its viscosity, the formation of the extruder sections located in front of and behind the annular gap, in particular the nature / configuration of the planetary spindles. This includes the number of planetary spindles as well as their conveying effect in front of and behind each dispersing ring.

This also includes the nature of the surfaces touched by the crop in the annular gap. Conventionally, the surfaces are smooth.

Optionally, the surfaces can also be profiled. Preferably, the groove provided for the dispersing rings in the central spindle is provided with a smooth surface, while the dispersing ring is profiled on the circumferential surface. The Profilgebung has either the shape of a helical toothing, wherein the slope is such that a resistance is built up against the passage of the feedstock.

Optionally, the peripheral surface is also provided with an arrow toothing. The arrow teeth have the shape of successive arrowheads. In the plan view, a zig-zag shape results on the peripheral surface of the dispersing ring. The arrow toothing increases the resistance 'against the passage of the material used even further.

The gearing is formed by recesses, which form the tooth gaps, are machined into the peripheral surface of the dispersion, for example milled.

But it can also be incorporated as Vertiefunmg tooth gaps in the peripheral surface. The pits can be the same or different. The wells can be open or closed. The depressions may have round and / or angular shape.

With small sizes as well as with large sizes of the planetary roller extruder, gap widths of, for example, 1 mm or 5 mm can be used.

The devulcanization be single-stage or multi-stage.

In the multistage devulcanization several dispersing rings are arranged one behind the other.

Each dispersing ring is preferably assigned a planetary roller extruder section / planetary roller extruder.

The dispersing rings may be the same. The dispersing rings can also be designed differently. Dispersing rings can be used whose gap width decreases with increasing processing distance and / or whose gap length increases with increasing processing distance. The processing line is the route on which the feedstock / material is processed. The processing distance becomes greater the more planetary roller extruders are combined / put together to form an extruder installation.

• -des zweiten Dispergierringes gegenüber der Öffnungsweite des ersten Dispergierringes um mindestens 4, vorzugsweise um mindestens 6, noch weiter bevorzugt um mindestens 8mm geringer ist,
• -des dritten Dispiergierringes gegenüber der Öffnungsweite des zweiten Dispergierringes um mindestens 0,5mm, vorzugsweise um mindestens 1mm, noch weiter bevorzugt um mindestens 1,5mm und höchst bevorzugt um mindestens 2mm kleiner ist.
• -des dritten Dispiergierringes gegenüber der Öffnungsweite des zweiten Dispergierringes um mindestens 0,5mm, vorzugsweise um mindestens 1mm, noch weiter bevorzugt um mindestens 1,5mm und höchst bevorzugt um mindestens 2mm kleiner ist.
• -des vierten Dispiergierringes gegenüber der Öffnungsweite des dritten Dispergierringes um mindestens 0,5mm, vorzugsweise um mindestens 1mm, noch weiter bevorzugt um mindestens 1,5mm und höchst bevorzugt um mindestens 2mm kleiner ist.

For example, extruder systems may arise in which the opening width

• the second dispersing ring with respect to the opening width of the first dispersing ring by at least 4 , preferably at least 6 , even more preferably at least 8mm smaller,
• the third dispensing ring is smaller than the opening width of the second dispersing ring by at least 0.5 mm, preferably by at least 1 mm, more preferably by at least 1.5 mm and most preferably by at least 2 mm.
• the third dispensing ring is smaller than the opening width of the second dispersing ring by at least 0.5 mm, preferably by at least 1 mm, more preferably by at least 1.5 mm and most preferably by at least 2 mm.
• the fourth dispensing ring is smaller than the opening width of the third dispersing ring by at least 0.5 mm, preferably by at least 1 mm, even more preferably by at least 1.5 mm and most preferably by at least 2 mm.

On the opening width of the gap has influence, which elements upstream or downstream of the respective dispersing ring.

The axial length of the gap of the dispersing rings depends on their thickness of the ring construction. The thickness may be, for example, 1 to 25 mm, preferably 3 to 20 mm.

Favorable is a variability of the gap length. In doubt, the change in the gap length by replacing a Dispiergierringes takes place against another Dispiergierring with greater or lesser thickness. However, at the same time this can force a replacement of the central spindle. The advantage is to leave the central spindle and the housing or the module housing and their distances unchanged. For this purpose, the replaceable dispersing rings can be provided on the housing side with a consistently thick collar and on the central spindle side with a collar which is thicker or thinner as desired.

The thicker collar and thinner collar design also allows the dispersing ring to be composed of two halves or more segments that are assembled around the central spindle, thereby engaging the collar in a groove of the central spindle.

The dispersing rings can be exactly cylindrical in the gap area. Preferably, the dispersing rings are rounded at the edges of the gap-forming surface and provided between the edges with a flow-conical taper, so that no dead spaces in the gap arise. Optionally, there is an entry cone and an exit cone on the dispensing rings. The exit cone may be longer than the entry cone or vice versa. The exit cone can also have the same length as the entry cone.

The conical surfaces of the dispersing rings preferably have an inclination of 1 degree to 45 degrees, even more preferably an inclination between 10 degrees to 35 degrees and most preferably an inclination of 15 degrees to 30 degrees to the central axis of the dispersing rings. The inclination of the entry cone may be equal to or different from the inclination of the exit cone.

The slit-forming surfaces also include the surfaces of the recess. Preferably, the edges and corners of the recess are also rounded in order to avoid dead spaces. Dead spaces are spaces in which material can settle without being pushed away by nachströmendem material.

According to the invention, the recess in the central spindle preferably remains unchanged and changes in the gap occur, in particular its widening or reduction and other shaping by changing the dispersing ring.

Advantageously, by controlling the temperature of the extruder influence on the deformability of the feedstock. By heating, the deformability increases, by cooling, the deformability decreases. This can also be used in order to use dispersing rings with a gap width or gap length, which only lead to insufficient processing of the feedstock at a different temperature of the feedstock.

With a modular structure of the extruder system, the dispersing rings can each be formed between two planetary roller modules and / or one forming the filling part and in the manner of a single screw trained module and a subsequent planetary roller module can be arranged. This facilitates the assembly of the dispersing rings and their replacement, so that the dispersing rings can be adapted to the respective starting material and the respective processing state in the system. This is especially true for dispersing rings that do not engage in a groove of the central spindle.

But even with dispersing, which engage in a groove of the central spindle, a replacement of the dispersion with different gap length is possible without the central spindle must be replaced, as long as the groove can be maintained.

The arrangement between two modules makes it possible to clamp the dispersing rings when clamping the associated module housing ends with. This advantage is usually also used for mounting the rings belonging to a planetary roller module. Preferably, the races and the dispersing rings are taken together in a common construction when the dispersing rings are used, for example, between two planetary roller modules. The common construction may be a centering ring in which the thrust rings and the dispersing rings are inserted. When clamping the housing, for example, the housing of the rear module in the conveying direction can press against the dispersing ring, the dispersing ring against the stop ring and the stop ring against the housing of the front module in the conveying direction. At the same time a centering of these machine parts is effected in that the centering ring is centered in the housing of the front module, the stop ring and the Dispiergierring is centered in the centering ring, and the housing of the rear-facing module on the Dispiergierring, because the dispersing ring with respect to the centering ring protrudes slightly and the projecting end is enclosed by the housing of the rear module.

The advantage of the arrangement of the dispersing rings between two adjacent planetary roller modules or between a filler module designed in the manner of a single-screw extruder and a planetary roller module can be so great that the module length is set to the desired position of the dispersing rings.

Incidentally, by using central spindles, which are also modular in design, a partial replacement of the central spindle take place with increasing gap length. Then, the replacement is limited to the respective spindle parts or associated with the replacement of the respective spindle parts gap change complements the gap formation associated with a replacement of the Dispergierringes.

The depoymerization temperature or the temperature for the devulcanization of waste rubber or similar elastomers is generally between 260 and 340 degrees Celsius. Preferably, a depolymerization temperature or devulcanization temperature is selected which is below the temperature at which a caking of the feedstock is located on the stop ring and / or on the dispersing ring. The advantage is to test the baking temperature before depolymerization. The testing can be done on the plant by gradually increasing the temperature until caking on surfaces of the stop ring and / or the Dispergierringes are detectable. The test runs are run for the duration of, for example, at least 8 hours, preferably for at least 16 hours, more preferably for at least 24 hours, and most preferably for at least 32 hours at the same temperature. After each test run, the temperature for the next test run is increased. The temperature increase is for example at least 5 degrees Celsius, preferably at least 10 degrees Celsius. The test runs may begin in the case of devulcanization of rubber or similar elastomers at 260 degrees Celsius, if indications of the approximate location of the baking temperature are lacking. After detection of caking, the temperature from the previous test run can be considered as a suitable operating temperature. After the positive test run, the thrust ring and / or dispersing ring can be cleaned and reused.

If a first test run is chosen on the basis of erroneous assumptions with too high a temperature, this is harmless, because after cleaning the run-up ring and / or dispersing ring a next test run can be carried out at a lower operating temperature.

For the temperature control according to the invention during depolymerization or during Devulkanisieren it is harmless if the Exrtrudertertemperatur during warming up of the feedstock in the extruder is higher than the operating temperature during Depolymerisieresns or during Devulkanisierens. The excessively high extruder temperature in the warm-up zone is advantageous for the warm-up rate and the length of the warm-up stretch. At higher extruder temperature, a larger temperature gradient arises in the warm-up zone, so that the warm-up accelerates and the warm-up zone is shortened.

After sufficient heating, depolymerization or devulcanization starts. It may be advantageous if the starting temperature is slightly higher than required for subsequent depolymerization or devulcanization. After starting the depolymerization or Devulcanization, the temperature is reduced again to a level below the baking temperature. as long as the feedstock has not yet reached the stop ring or dispersing ring. the temperature of the material to be used when reaching a stop ring and / or dispersing again below the baking temperature.

In addition, it may be desirable to reduce the temperature of the planetary roller module to the planetary roller module to maintain the viscosity of the feedstock at the same level during devulcanization. It is also possible to change the viscosity by changing the cooling and optionally by heating and by further mechanical processing.

The associated temperature of the temperature control is in the appropriate amount to the temperature of the feedstock / treated good. Correspondingly, when cooled, the temperature of the tempering agent is lower than that of the feedstock to provide the necessary temperature gradient to produce the desired heat flux from the feedstock to the tempering agent. Accordingly, when heated, the temperature of the tempering agent is higher than that of the feedstock to produce the necessary temperature gradient to produce the desired heat flux from the tempering agent to the feedstock.

Too cold starting of the extruder is not recommended, because this can easily lead to an operating stoppage.

For the cooling / heating in the housing (between the internally toothed bushing and the surrounding housing), a different tempering means is preferably used than for the above-described cooling of the starting ring or dispensing ring.

Up to a temperature of 350 degrees Celsius can be used in housing cooling with commercially available oils as tempering. Although it is possible to work with oil as a tempering agent above 350 degrees Celsius. However, the oil should be under nitrogen or other inert means to counteract inflammation of the oil.

Advantageously, the cooling of starting rings according to the invention is also possible independently of dispersing rings or the cooling of dispersing rings independently of start-up rings. Likewise, a cooling according to the invention of the starting ring and / or dispersing ring is also possible independently of devulcanization. This applies, for example, to the processing of elastomers, in particular non-thermoplastic elastomers, as well as to the processing of other plastics having a profile comparable to the processing, such as elastomers. When applied to other elastomers and plastics, the temperatures are different than those of the waste rubber, which must be cooled to prevent caking.

In the drawing, an extrusion plant for a method according to the invention for the application to waste rubber is shown.

1 shows an older scheme for a plant for the devulcanization of Altgumme with various planetary roller extruder sections / modules.

The extrusion line is 70 years old. The system according to the invention consists of different sections 2 . 3a . 3b . 4 . 5 . 6 , The section 2 is a filling part and designed in the manner of a single-screw extruder.

The sections 3a . 3b . 4 . 5 . 6 are planetary roller modules. Among the various planetary roller modules include internally toothed cylindrical housing, not shown planetary spindles and a central spindle, not shown. Here, a common central spindle is provided for all planetary roller modules and for the filling part. That is, the center spindle extends through all planetary roller modules and through the filling part 2 to the gearbox 1 out. The gearbox is moved by a drive motor. As a result, the central spindle rotates in the extruder. The planetary spindles meshing with the central spindle run around the central spindle and mesh with the internally toothed housing of the planetary roller modules. The planetary roller modules 4 . 5 and 6 have a length of 400 mm each. The planetwave modules 3a and 3b have a length of 200mm each.

In all planetary roller modules each five planetary spindles are provided. The number of planetary spindles has an influence on the degree of filling of the planetary roller modules. The smaller the number of planetary spindles, the larger cavities can be generated. The planetary spindles of the modules 4 and 5 are designed as Noppenspindeln and evenly distributed around the circumference of the central spindle. From the planetary spindles of the module 6 are three planetary spindles also formed as Noppenspindeln. The remaining planetary spindles of the module 6 are designed as transport spindles. The planetary roller modules 3a and 3b have more planetary spindles than the other planetary roller modules, namely six. In addition, the planetary spindles of the modules 3a and 3b provided with a standard toothing. The standard gearing causes a stronger mechanical load of the scrap rubber than in the other modules provided planetary spindles whose Noppenspindeln the degassing are very conducive and the transport spindles are both the degassing conducive, as well as develop a significant conveying effect. In the standard gearing, a very strong rolling out of the scrap rubber into thin layers takes place. This intensifies the heat flow.

Of planetary spindles in the planetary roller modules 4 . 5 . 6 each have three nubs spindles the same length of 373 mm. The other planetary spindles are longer. They have a length of 399mm. The planet spindles of different lengths are advantageous for drawing in the old rubber in the area of action of all spindles.

Planetary roller module 3a and 3b In contrast, three planetary spindles are provided with this length. The remaining three planetary spindles have a shorter length of 373 mm.

All planetary spindles slide on standard starting rings. The thrust rings are connected in the exemplary embodiment with Dispergierringen to form a ring construction.

• die Ringkonstruktion für den Modul 3b mit 20,
• die Ringkonstruktion für den Modul 4 mit 21,
• die Ringkonstruktion für den Modul 5 mit 22.
• Außerdem ist auch am letzten Modul 6 noch eine Ringkonstruktion 36 vorgesehen.

The ring construction for the module 3a is with 19 designated,

• the ring construction for the module 3b With 20 .
• the ring construction for the module 4 With 21 .
• the ring construction for the module 5 With 22 ,
• Besides, it is also on the last module 6 another ring construction 36 intended.

2 includes a schematic diagram of an inventive ring construction with a stop ring 52 and a separate dispersing ring.

The stop ring 52 sits in a recess of the extrusion in the rear housing end 51 , The housing end is shown without conventional socket and without teeth for the planetary spindles, not shown. The stop ring 52 surrounds the central spindle at a distance. From the central spindle is the center 56 shown in phantom, the gearing 57 dashed.

The planetary spindles revolve around the central spindle and slide on a hard metal layer 55 of the stop ring. 55 , In addition to the stop ring 52 the separate dispersing ring sits in the recess of the housing end 51 , The dispersing ring also sits in a recess of the opposite housing end 50 ,

Towards the center, the dispersing ring projects into a groove in the central spindle. This leaves a gap between the dispersing ring and the central spindle for the passage of feedstock

The dispersing ring has a circumferential cooling channel 58 ,

The cooling channel 58 is through parts 54 and 55 educated. The part 55 has a U-shaped cross-section through the part 54 is closed. The part 54 forms a lid.

For installation in the groove of the central spindle, the dispersing ring is also composed of two ring halves. As a result, there are two halves that together form the part 55 form, and two halves, which together form the part 54 form.

Before closing the opening of the U-shaped part 55 with the part 54 An inlay is placed in the opening with which the entire cooling channel 58 is lined and all potential leaks are eliminated, which exist at the joints of the dispersing ring forming parts.

In the embodiment according to 2 the cooling channel is high.

If necessary, the cooling channel may be sufficient for a cooling channel which is much smaller in cross-section and which cools the part with which the dispersing ring protrudes into a groove in the central spindle. An inlay for such a cooling channel is shown 3 ,

To 3 the inlay is going through a pipe 60 formed, that has a flat, rectangular cross-section. The pipe 60 is added to a ring with a break 61 bent. At the ends there is a supply line 62 and a derivative 63 for coolant ..

4 shows an inlay 67 with a supply line 68 and a derivative 68 which is between dispersing ring parts 65 and 66 is held. The dispersing ring part 65 has the cross-section of an angle profile (L-profile). The other dispersing part 66 has the cross section of a U-profile with a leg lying on the outside circumference, which extends in the axial direction over the leg of the dispersing ring part pointing outwards in the radial direction 65 extends. Between the lower leg of the dispersing ring part 66 and the lower leg of the dispersing ring member 65 is a flattened bent copper tube 67 intended. This tube corresponds to the in 3 illustrated tube 60 , The supply line for coolant on the pipe 67 is with 68 denoting derivative with 69,

During assembly, first the pipe 67 on the lower leg of the dispersing ring part 65 pushed, then the dispersing ring part 66 over the pipe 67 pushed. Slots prevent this 70 in the area of the supply line 68 and the derivative 69 in that the dispersing ring part 66 when sliding on the supply line 68 and the derivative 69 Keeps hanging.

The 5 to 9 show further variations of profile cross-sections to form a dispersing ring with a trapped cooling channel. In schematic view.

• nach 6 ein L-Profilquerschnitt mit einem Z-Profilquerschnitt;
• nach 7 ein Sonderprofilquerschnitt mit einem L-Profilquerschnitt entsprechend 4;
• nach 8 zwei U-Profilquerschnitte79;
• nach 9 ein L-Profilquerschnitt 75 mit einem U-Profilquerschnitt.

They are after 5 two angle profile cross sections (L profile cross sections) 75 combined with each other;

• to 6 an L-profile cross-section with a Z-profile cross-section;
• to 7 a special profile cross-section with an L-profile cross section accordingly 4 ;
• to 8th two U-profile cross-sections 79 ;
• to 9 an L-profile cross-section 75 with a U-profile cross section.

The modules 3b . 5 . 6 are with a degassing 30 . 32 . 35 Mistake. The degassing is formed by side arms extruder, which are perpendicular to the associated modules contrary to the representation of the drawing.

• der Seitenarmextruder 30 geringen Abstand vom Dispergierring 19, der Seitenarmextruder 32 geringen Abstand vom Dispergierring 21,
• der Seitenarmextruder 35 geringen Abstand vom Dispergierring 22.

It has

• the side arm extruder 30 small distance from the dispersing ring 19 , the side arm extruder 32 small distance from the dispersing ring 21 .
• the side arm extruder 35 small distance from the dispersing ring 22 ,

At the Seitenarmtextrudern is in each case negative pressure. During degassing, the side arm extruders are driven empty, so that feed / treated material, which is under pressure in the extruder or is inclined to exit with withdrawn gas, is forced back into the extruder.

The waste rubber is fine-grained in the embodiment in the embodiment 2 metered. The dosage is with 7 denotes the material entry with 40 , At the material inlet is beyond an opening 41 provided that can be blown through the remaining material at standstill material.

The planetary roller modules 3 . 4 5 are with oil coolers 10a . 10b . 11 . 12 . 13 tempered during the Devulkanisierungsbetriebes.

The filling part has a temperature control 14 ,

Furthermore, a tempering 15 provided for the central spindle, not shown

When starting, first oil is pumped 45 entered into the filling before the filling part is loaded with waste rubber. This prevents dry running of the moving extruder parts.

After entering the old rubber in the filling part 2 Exists the old rubber through the screw of the filling a mechanical deformation and stress. At the same time the old rubber undergoes a warming. This is the tempering of the temperature 15 for example, set to a temperature of 120 degrees Celsius. Other examples use lower or higher temperature. Preferably, the temperature 15 is adjustable up to 140 degrees Celsius.

The old rubber is removed from the filling part 2 in the module 3a pressed, which forms a warm-up zone. In the warm-up zone, the old rubber is heated to a material-dependent starting temperature for devulcanization. The starting temperature in the example is 310 degrees Celsius. This is the tempering 10a of the module 3a set to 330 degrees Celsius in the example. At the same time there is an intensive mixture and Auswalzung the old rubber in the module 3a instead of.

After the old rubber has been heated up to the starting temperature, the waste rubber passes through the gap on the dispersing ring 19 pressed. After passing the dispensing ring 19 the molecular chains of the waste rubber are broken up so far that sulfur can escape from the feed / treated material. The escape of the sulfur is promoted by intensively mixing and rolling the feedstock in the module 3b. At the same time, gaseous sulfur liberated via the degassing 30 aspirated.

In the module 3b the devulcanization of the feedstock is started.

In order to achieve sufficient devulcanization, the processing must be continued.

From the module 3b the feedstock / items to be treated is added to the module 4 pressed. The Einazmaterial / treated material passes the dispersion ring 20 , In the module 4 the feed / material to be treated is treated further and by another dispensing ring 21 pressed. The material processed in this way will be in the module 5 further processed and degassed.

After exiting the planetary roller module 5 the devulcanized waste rubber is in the planetary roller module 6 cooled to 220 degrees Celsius, before being in crumbly form from the extrusion line exit and in a water cooling 16 is cooled to room temperature.

For cooling is a water cooler 13 on the planetary roller module 6 intended.

Also the filling part 2 is with a water cooler 14 Mistake.

The cooling temperatures at the filling part and after devulcanization are also dependent on the material.

In the embodiment, moreover, an internal cooling of the central spindle is provided. The associated radiator 15 is like the coolers 10 . 11 . 12 an oil cooler and set to a temperature of 300 degrees Celsius.

The Devulkanisierung is effected by the mechanical and thermal stress of the waste rubber in the extrusion plant.

For mechanical stress in the planetary roller modules 3 . 4 . 5 also carry the dispersing rings 20 . 21 . 22 at.

In the exemplary embodiment, the dispersing rings are arranged in the conveying direction of the waste rubber through the system behind the starting rings, not shown.

In this case, the inner diameter of the dispersing rings 20 . 21 . 22 smaller than the outer diameter of the central spindle or the head diameter of the central spindle outer toothing. The dispersing rings 20 . 21 . 22 engage in grooves (not shown) in the central spindle, so that the tooth spaces between the teeth of the central spindle are closed except for a narrow gap on the tooth base. The dispersing rings 20 . 21 . 22 Incidentally, they are held between the corresponding ends of the planetary roller modules, so that also the housing space surrounding the central spindle is closed and the waste rubber is forced to penetrate through the narrow gap. The narrowing of the gap is material dependent and causes extreme deformation and extreme mechanical stress of the feedstock.

In particular, the dispersing ring 20 between the planetary roller modules 3 and 4 , the dispersing ring 21 between the planetary roller modules 4 and 5 and the dispersing ring 22 between the planetary roller modules 5 and 6 intended.

The clamping of the dispersing rings 20 . 21 . 22 takes place when bracing the cylindrical housing of the planetary roller modules 3 . 4 . 5 . 6 ,

The planetary roller modules 3 . 4 . 5 . 6 have at their ends usual flanges, which are pulled against each other with clamping screws. Also the filling part 2 has usual flanges, With these flanges, the filler is on the one hand to the housing of the drive 1 clamped and on the other hand with the planetary roller module 3 braced.

For in the embodiment in grooves of the central spindle cross dispersing 20 . 21 . 22 it is envisaged that these rings are composed of two halves to facilitate assembly.

The assembly is subsequent to the dispersing ring 20 explained. The assembly of the remaining dispersing rings 20 . 21 . 22 takes place accordingly. After mounting the Füllteilgehäuses the central spindle is first pushed with her designed as a single screw end into the Füllteilgehäuse and coupled to the drive.

Subsequently, the housing of the planetary roller module 3 pushed over the central spindle and clamped with the Füllteilgehäuse.

This is followed by the positioning of the planetary spindles of the planetary roller module 3 , For this purpose, the planetary spindles are pushed in rotation into their intended position between the housing and the central spindle. The position of the planetary spindles is characterized by uniform distribution on the circumference of the central spindle and the already described meshing engagement of the planetary spindles with the internal teeth of the housing and the external teeth of the central spindle.

After positioning the planetary spindles, the thrust ring for the planetary spindles is pushed over the central spindle and into a centric opening of the housing end of the planetary roller module. The contact ring carries in the contact area with the planetary spindles a hard metal layer in the form of an inserted carbide ring as wear protection.

After positioning of the thrust ring, the dispersing ring consisting of two halves becomes 20 brought to the stop ring to the plant. The halves are pushed into a groove of the central spindle at the same time. The centering of the dispersing ring is then carried out with the aid of a one-piece support ring, which can be pushed over the central spindle and in turn in the same housing opening as the stop ring centering in the planetary roller module 3findet. The support ring is also sized so that it from the end of the housing opening of the planetary roller module 3 protrudes and a centering for the subsequently mounted housing of the planetary roller module 4 forms.

The housing of the planetary roller module 4 is doing with the housing of the planetary roller module 3 clamped in the form described above. This tension also causes a tension of the stop ring, the dispersing ring and the support ring.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 60004885 T2 [0014]
• DE 909041 [0015]
• DE 60008279 T2
• DE 60215210 T2 [0016]
• DE 60120804 T2 [0018, 0021, 0024]
• WO 2011/091966 [0022, 0028, 0029, 0037, 0054, 0081]
• DE 69329245 T2 [0024]
• DE 69724239 T2
• DE 102009019846 [0045]
• DE 102009013839 [0045]
• DE 102008063036 [0045]
• DE 102008018686 [0045]
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• DE 102007040645 [0045]
• DE 102004048440 [0049]
• US 7476416 [0049]
• EP 702739 [0078]

Claims (19)

A process for devulcanizing rubber and breaking the crosslinking of other elastomers, wherein the molecular chains are at least partially destructible by mechanical and thermal stress, in particular for devulcanizing sulfur crosslinked rubber, wherein the mechanical and thermal stress is generated in a planetary roller extruder, the planetary roller extruder a housing, planetary spindles and a central spindle and the central spindle meshes with the planetary spindles and the planetary spindles meshes with an internal toothing of the housing or the internal toothing provided in the housing sleeve, so that rotation of the central spindle causes a rotation of the planetary spindles about the central spindle in the housing wherein the planetary spindles of an extruder section with an end face on a stop ring of this extruder section slide and / or in the planetary roller extruder a dispersing ring is provided, the flow cross section for d The feed material is reduced more than a stop ring, characterized in that the stop ring is cooled at the contact surface with the planetary spindles and / or the dispersing ring on the surfaces touched by the feedstock to a temperature below the temperature at which hydrocarbons on the stop ring and / or Bake the dispersing ring. Method according to Claim 1 characterized in that the caking temperature is tested in operational tests, wherein the operating temperature of the extruder is increased in increments of at least 5 degrees Celsius, preferably at least 10 degrees Celsius and the extruder in each step at least 8 hours, preferably at least 16h and even more preferred for at least 24 hours and most preferably at least 32 hours at the same temperature until caking occurs, so that the operating temperature of the previously run without caking test step is the correct operating temperature. Method according to Claim 2 CHARACTERIZED IN THAT the operational trials begin processing rubber or like elastomers below an extruder temperature of 260 degrees Celsius. Method according to one of Claims 1 to 3 , characterized in that a stop ring is used, the contact surface with the planetary spindles is formed by a hard metal layer and the other contact surfaces are provided with the feedstock with a ceramic layer. Method according to one of Claims 1 to 4 , characterized in that a dispersing ring is used, which is provided at the contact surfaces with the feedstock with a ceramic layer. Method according to one of Claims 1 to 5 , characterized in that a stop ring and / or dispersing ring is used which has an internal closed cooling channel with a supply line and a discharge for coolant, wherein the stop ring surrounds the central spindle at a distance and the dispersing ring preferably engages in an annular circumferential groove of the central spindle wherein the dispersing ring engaging in the circumferential groove is even more preferably composed of several parts in the circumferential direction. Method according to Claim 6 , characterized in that a thrust ring and / or a dispersing ring are used, which are clamped together, leaving a cavity between the two rings, which forms the cooling channel. Method according to one of claims 1 to 7, characterized in that an inlay is inserted into the starting ring and / or the dispersing ring, which forms a seal of the cooling channel at the junction of the plant ring part and / or the dispersing ring parts. Method according to one of Claims 1 to 8th , characterized by plant ring parts and / or dispersing ring parts, which consist in cross-section of -U-shaped profile and I-shaped profile or two angle profiles or a Z-profile and an angle profile or two U-shaped profiles or a U-shaped profile and an angle profile Method according to Claim 8 or 9 , characterized by using a copper tube as inlay with supply and discharge for the coolant. Method according to one of Claims 8 to 10 characterized by using a tubular inlay with a flat cross-section. Method according to one of Claims 8 to 11 , characterized by the use of a Inlays where the coolant supply and discharge are diametrically opposed to the inlay. Method according to one of Claims 8 to 11 , characterized by the use of an inlay, in which the supply and discharge for coolant are adjacent to each other and between the supply line and the discharge a closure of the channel-forming inlay is provided. Method according to one of Claims 8 to 13 characterized by the use of a bendable inlay. Method according to one of Claims 1 to 14 , characterized by the use of compressed air as a coolant. Method according to Claim 14 characterized by the use of compressed air containing fine water droplets that evaporate at the temperature in the cooling channel. Method according to one of Claims 1 to 16 , characterized in that the extruder is moved in the warm-up phase for the feed before the start of depolymerization or devulcanization with an operating temperature above the baking temperature. Method according to one of Claims 1 to 17 characterized by a stepwise devulcanization with a plurality of dispersing rings arranged one behind the other, wherein each dispersing ring is assigned a planetary roller extruder section / module and wherein the annular gap associated with a dispersing ring following in the direction of extrusion is greater than the annular gap associated with the upstream dispersing ring. Method according to one of Claims 1 to 18 , characterized by a profiling of at least one contact surface with the feedstock in the annular gap.

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