DE1454801A1 - Method and apparatus for removing moisture from non-rigid elastomers - Google Patents

Description

Λ F.

H54801

S 14 54 801.7
(J 21 200 X / 59

DiTERHATIONAL BASIG ΒΟΟΝΟΜΪ CORPORATION

Method and apparatus for removing moisture made of non-rigid elastomers

The invention relates to a method and device. the preliminary dehydration and drying of course · *, more aesthetic and recovered rubbers, as well as non-rigid slastomeres »The invention relates in particular to · a method and a device for d & s provisional

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New documents (Art 7 § ι Ai ^ 2 No. ι sentence 3 dee AmendmentwoHwo ^ « 4 ^ a itlzt

DIPL. ING. J, P. WOOHINQBR iWietel · »'

■ ■ TM. Mil4

Dewatering such materials in continuous Method of operation, followed by a process and a device for continuously increasing the temperature of these materials and the retained water, heating to the point where the "moisture contained in the materials" evaporates immediately under the conditions of rapid evaporation and rapid evaporation carried out at normal pressure or negative pressure cooling takes place.

During the Second World War a number of plants were built to make a copolymer from butadiene and styrene and process. This copolymer was named GHS rubber at the time and is now commonly used as SBR rubber called. The polymerization is carried out in an emulsion of the raw materials in water. After this Completion of the polymerization will be the, unreacted Butadiene and styrene are drawn off from the emulsion of the rubber in water. Then an acid or an acid salt is added to the emulsion to coagulate the rubber contained therein. Here receives one a crumbly product "

The more special rubbers that have been used in recent years

were developed, e.g. butyl rubber and polybutadiene rubber, are carried out by means of a polymerization carried out in the presence of an organic solvent After the polymerisation, the organic solvents are also produced by the rubber material deducted. Although this stripping is done in various ways, most will involve such Working methods using water as a carrier for the ^ ouchuk.

Because of these processes, various raw materials are still polymerized into non-rigid elastomers and due to the devices in use and procedures for removing the unreacted components and / or solvents from these materials, Most such non-rigid elastomers subsequently appear as an aqueous slurry. Since the Use of such non-rigid elastomers means removal which makes water and volatile solvents in general necessary, this must be practical be completely removed from the elastomer.

jjie quite generally previously used procedure for the distance; unbound 7 / asters is that

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a vacuum rotary drum filter system or rubber rollers can be used. This finish reduces the moisture content of various non-rigid elastomers to about 25 to 55 % . The elastomers thus freed from the easily removable water are then passed through a comminution device and fed to hot air dryers. In these dryers, of course, the hot air evaporates the water contained in the crumbly particles of the elastomer, and the temperature of these particles is brought to values of about 93 ° 0. The relatively long period of time within which the elastomers are subjected to the relatively high temperatures has an unfavorable effect on the quality of the elastomer. The capital investment for such drying facilities is excessive, a large area is required for these facilities, and the cost of repairing such facilities is high.

After performing the preliminary dewatering above , the elastomer can also be dried in large mixers, some of which are commercially available under the designation Banbury-Misoher. These units can accommodate batches of around 200 kg per batch. By driving the Khet elements with electric motors of about

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1500 HP is generated by the frictional heat on the elastomer brought a temperature of 150 to 200 ° O. During this During the operation, steam can be removed from the mixer; this is done at the end of the operation However, elastomers are literally blown out of the mixer to allow moisture to escape. These units also require high capital investment and have all the restrictions which are associated with a batch process. Furthermore, additional equipment, in general requires a crushing and extrusion device, in order to bring the rubber dried in this way into a packable form.

A recently developed method for drying elastomers consists in that the materials are subjected to preliminary dehydration in the above-described manner and the same are then continuously fed to a continuously operating screw device, in which the housing can be heated with steam · This Machines work on the principle of converting electrical energy into thermal energy in order to maintain the temperature of the To increase elastomers and remove the water they contain. When a temperature of 120 ° bia is reached

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205 ° C is allowed to escape by appropriate arrangements, so that the heating of the rubber takes place continuously with and after the escape of the steam. With various devices of this Kind are one, two & i or three exit devices for the water vapor provided. Thus, the temperature control of the elastomer is as it passes through it Device difficult. Overheating of the elastomer occurs due to continued heating during and after the water vapor has escaped. Similarly, as a result of the leakage of water vapor from the elastomer, the rate of heat transfer of this device is relatively slow. In the end after the elastomer has emerged from the device "at temperatures of 150 ° 0 or above there is no expedient effective device that cools the rubber and thus prevents it from decomposing.

The term "dewatering" used here is to be understood to mean the preliminary removal of easily separable water up to about 5 to 20 % water content, and the term "drying" is used here to include the practically complete 3 ? «Moisture removal is to be understood, for example a

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Remove moisture to less than 0.5 fo water.

According to the invention, an effective method and advantage ^!

direction for preliminary drainage is not more rigid

Elastomer brought in proposal.

Such a method is also in accordance with the invention and proposed apparatus for dewatering non-rigid elastomers so that the dewatered elastomer can be dried more effectively in hot air dryers.

A method and device are also in accordance with the invention proposed for the preliminary dehydration not rigid ülastomerer, so that the dehydrated material can be processed immediately in mechanical dryers.

It also belongs to the purposes of the invention, a method and device in proposal zn. tringen, through which the drainage of non-rigid elastomers can be carried out more effectively in non-continuously working screw arrangements.

Furthermore, it is a purpose according to the invention to provide a

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drive and device · for drying not more rigid Run elastomers at relatively low and controlled temperatures.

It also belongs to the purposes of the invention to provide a method and apparatus for drying that are not more rigid To propose elastomer, so that a sonell evaporation cooling an immediate temperature reduction of the elastomer after it has been released from the drying device.

Another purpose of the invention is to provide a method and to propose apparatus for drying non-rigid elastomers under conditions such that the period of time during which the El $ .f1? omere the drying temperature. doors is suspended «to the smallest possible range is decreased.

A method and device are also in accordance with the invention proposed for drying non-rigid elastomers in order to improve the quality of aerated elastomers.

In addition, a method and device are provided according to the invention

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for dewatering and drying non-rigid elastomers suggested, for which less tree is needed than before.

A method and device are also provided according to the invention for dewatering non-rigid elastomers under such conditions that monitoring the particle sizes of the dewatered elastomer mSglloh w ± rd.

A method and device are also in accordance with the invention proposed for drying rubber under conditions such that it will leak from the drying device - de rubber is present in particulate form and the same not, as before, undergoing treatment in an extrusion apparatus requirement.

Finally, the purposes according to the invention also do not include a method and device for drying to bring rigid Jülastomerer in proposal, namely in continuous operation, due to the simultaneous, but controlled during the drying process Vlfeise, a vigorous kneading of the elastomer is carried out will.

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The invention is explained in detail below with reference to the accompanying drawings.

β 4

]? ig. 1 is a side elevation of several important ones Components of a combined dewatering and drying arrangement to carry out the • procedure according to the invention |

Fig ». Figure 2 is a view partly in vertical section and partly in side elevation on a somewhat enlarged scale, the right end of the upper or drainage unit after Fig. 1 shows

Figure 2A is a view similar to Figure 2 showing the left hand end of the top or drainage unit of Figure 1. The lines AA of FIGS. 2 and 2A show the parting plane on which the drawings 2 and 2A can be put together to give the complete unit »u. . The Jiinie 2Δ of Figure 4 shows the location of the ^ex: section of Fig. 2A.

Fig. 5 and 4 are views in section _t in the ent-

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speaking along lines 3-3 and 4-4 of Fig. 2A are drawn |

Fig. 5 is a sectional view taken along line 5-5 of Fig. _4f

Fig. 6 is a somewhat enlarged longitudinal view vertical section showing the right end of the lower or drying unit of FIG

FIG. 6A is a view similar to FIG. 6, but shown shows the left end of the drying unit. The line BJ3 of FIGS. 6 and 6A show the parting plane of the two parts on which Figures 6 and 64 can be assembled so as to show the complete drying unit.

Figures 7 and 8 are corresponding sectional length views lines 7-7 and 8-8 of Fig. SA *

Fig. 9 is a broken away view in section length the line 9-9 of FIG. 8 in a somewhat enlarged Scale.

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Fig. 10 is a view in vertical section along its length "of the line 10-10 of FIG. 6, somewhat enlarged, with the valve closed j

Pig. 11 is a view of a part broken away the tip of the valve shown in fig * 10, the valve being partially open.

With reference to FIG. 1, it is simplified here Form a device for dewatering and drying a suspension of the polymerized elastomer in water The slurry is shown from the top right of the drawing, either a conveyor belt 20 or corresponding Sahütte or Bohr, delivered into a receptacle 21 of the first or drainage unit 22 "

The so-called "free" water, ie water that flows off due to the action of gravity and corresponds to a water content of over 50% , can be let out before the material is introduced into the container. Removal of the free flowing water can be accomplished by making the elastomer slurry

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and passing water over an inclined screen and vibrating screen. The elastomer passes continuously through the unit 22, forcing out a substantial amount of the retained water. In this first or dehydration step, the water content is from 5 to 20 wt.% Depending on the specific composition and mechanical properties of the elastomer is reduced.

When the second unit 23 according to the J? Ig. 1 to Drying of the dehydrated elastomer is to be applied, this elastomer becomes after dispensing from the unit 22 introduced into a storage container 24 and passed from here through the unit 23. From this unit 23 comes out the product in dried form, the same having a water content that is only a small proportion of 1%. The elastomer is then switched to a «! Conveyor belt 25 or the like. Removed.

Although each of the units 22 and 23 is separate. "* a connection with either a new type of or fore * kaoaten other device and procedure are used can, it is regarding an effective and economical lend Working method is most expedient when the combined yor-

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direction is applied in the manner shown here.

The method of operation is described in detail below, reference being made to specific components of the respective units 22 and 23.

The dewatering unit is shown in FIGS. 2, 2A, 3, 4 and 5. The same is an elongated, cylindrical housing 28 which is open at its right end (FIG. 2) and has a guide opening 29 which is connected to the chute 21. The drum is composed of an arrangement! Promiielstangen 30, as it is in particular from the S ¹ Ig. 2 and 3 can be seen. The one after Pig. The rods shown in section 3 are held together by semicircular brackets 31 which are fixed by means of large clamping bolts 32. Arranged at a distance from one another and shown here diametrically opposite one another, sea rods 34 protrude into the Iroflnaei, the purpose of which is explained below: "The Tromiaelst'angeii are, for example," held slightly apart by means of detachments (not shown) "so as to allow exit spaces result through which the liquid can be pushed. These gaps but not ^r slod large enough "to an outlet of the fixed

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A rotating shaft 55 is axially arranged in the drum, which is driven by a corresponding drive device and gear (not shown) is driven, the gear ratio is present within the housing 56. Conventional bearing arrangements including ball bearings and suitable ones Seals are provided within housing 56 (Fig. 2). Similar storage arrangements are for the other end of the '.Yelle provided, as this is however is a conventional arrangement, they are not shown in detail. It is enough to point out that the shaft rotated depending on the respective needs and their speed can be controlled.

On r.aben or sleeves 57, 58, 59, 4-0 etc. are a Set of corresponding tendon canals 57a, 58a, 59a, 40a etc. worn. The screw flight 57a represents a screw conveyor, which the material from the feed opening 29 receives from and to the left (Fig. 2) into the drum transported. The screw conveyor points over its length has a constant pitch and exerts only limited compression on the elastomer, albeit a certain one .Resistance to forward movement is opposed to the through the adjoining pressure screws (tendon

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gears 3Ba, 39a, 40a etc.) and the knife tips 34a exercised, did pursue between the snails. protrude inside, the circumferential edgeQ of the left end of the Feed corner 37 points opposite the inner circumferential surface the drum bars 30 have a slight play.

The continuous feed screw 37a feeds the wet Elastomers to the left, where the same oken passages 38a, 39e. 40a, 41a and 42a were added will. These shafts also have opposite there is a slight play to the inner sense of the word, and a knife point jumps nfcoh inside between each one adjacent pair of son corners before · Continue in working direction to the left end of the ψβΐΐ © takes the pitch. each Sohneokenganges compared to the previous ßchneckengang so that gradually the applied to the elastomer Print is enlarged. .

At the delivery end of the drainage unit, the one on the left At the end of the jig, -2A is an adjustable lever 45 arranged, the length of the shaft 35 can be moved forwards or backwards, so as to enlarge or enlarge the exit surface 46 (FIGS. 2A and 5)

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ring, through which the dehydrated elastomer is essential is pressed out. The well · 1st at 35a ai * thread provided to accommodate a nut 47 that the Cone at each selected point against the druok dea holds out of the material. When decreasing dtp opening 46, of course, the pressure exerted on the moving elastomer is increased. The cone 45 rotates with it of the shaft 35 and carries one arranged around the circumference Row of cutting bars 48 (Fig. 4 and 5) which are in sliding contact on a second row of cutting devices

49 are rotated past, which is firmly attached to the delivery frame

50 of the drum are arranged, as in particular in the ^ ig. 2Δ, 4 and 5 is shown. By selecting the number and spacing of the interacting cutting elements 48 and 49, the dimensions of the pieces of exiting elastomer can be controlled.

The cutting elements 48 rotating with the cone can to the left or right, see #ig. 2A and 5 »are moved, so that the working relationship with the fixed son elements 49 during an end shot of the « Kegels is maintained. In the embodiment shown, the cutting bar 48 is carried on a projection 53 which is attached to a slider 55 by means of bolts 54,

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the position of this slider by a «with a thread provided adjusting rod 56 is controlled, the stepping through a projection 57 on the cone body. After the final movement of the cutting rod 43 into the desired operating position, the rod 56 is in this Position held by nuts 53. The independent setting of the cone naturally requires a compensating adjustment of the sons 48,

Since "nioht rigid elastomers, which may contain 50 to 60% moisture is ran by the T sport worm 37 the Druckeohneoken 38» 39 _t ^ O, etc. supplied tfie forth above, some compression of the elastomer is carried out in the transport screw, In accordance with this partial compression, the water is released from the elastomer through the spaces between the Tromael rods 30, see Fig. 3b. In the manner shown, these rods can be held at a distance of 0.5 to 2.1 mm e.g. by means of spacers (not shown), so that the water can easily flow out of the elastomer due to the slight compression of the same in the oil conveyor screw 37 .

In the remaining part of the drum in the print area

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the device drum bars are also arranged, which can have a distance τοη 0 _f 127 to 3 »16 mm. By using the pressure screws 38-42 at selected distances from one another, the elastomer is further compressed so that the water contained therein is forced out through the openings in the drum. The removed water is collected in a bowl 60 and discharged through the pipe 61. By adjusting the conical delivery mechanism 45, a greater or lesser compression of the elastomer can be achieved compared to the compression caused by the arrangement of the corners of the son. By rotating the cone assembly 45 attached to the drive shaft and the corresponding rotary cutter 48 (Fig. 5), relatively thin slices of the dewatered elastomer can be removed from the device.

It has been found that a certain combination of the arrangements the device according to the invention enables an improved degree of effectiveness of the water warning and better hospitality with regard to the applied resources gie Isü ^ 'örisieien. When processing elastomers it was found that the screw conveyor 37 a complete screw flight into the drum housing protruding iflußv 'Afenii the transport screw niAHn dae

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When the drum housing protrudes into it, the elastomers tend to collect in the feed container 21 and inlet opening 29 and offer resistance to transport into the pressure area of the device. The knife bar members 34 are used to prevent rotational movement of the JBlastoren within the pressure section of the device. It has been found, however, that the use of grooved drum bars, as shown by reference numeral 30a in Figure 3, substantially increases the volumetric efficiencies of the son corners. It has also been found that the use of decreasing pitches in the pressure area of the device along with the knife bars 34 and fluted drum bars 30 is preferred to densify the elastomer sufficiently to allow the elastomer to dewater to 10 % moisture content. Finally, it has been found "That the operation of the" screw shaft with the prints without corners 38-4-2 with such a number of revolutions that the volumetric efficiency of the son corner is in a range of 10-50 % requires that a cutting of the compressed rubber in the Pressure zone takes place through the leading edges of the pressure son corners 38-42, so that this results in briefly opened channels through which the water out of the compressed mass

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and can flow out through the spaced-apart drum bars. It thus follows that different diameters and lengths of the device can be used in different fields of application, depending on the desired throughput. It will also be appreciated that various shapes of cutting assemblies 48 and 49 can be used to subdivide the size of the densified and drained elastomer into fine sections.

When the dehydrating device according to the invention is used before air dryers, it appears that the porous structure of the dehydrated rubber is essential for the final drying of the material by passing it through hot air on a continuously moving layer of the material. It has been found, for example, that the device described here, in certain operation, leads to a highly compacted and non-porous mass which has to be treated in a hot air dryer for about 2 hours in order to bring the moisture content to less than 0.5 / 0 , Bs However, it has been found that when the dewatering device according to the invention is operated with such a number of revolutions of the shaft that the efficiency of the screw is in a range of

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is preferably kept 10 to 20 % , but a range of 5 to 30 % is possible with a certain selection of the screw arrangements, a porous structure of the dewatered rubber is obtained. For example, a mass of rubber crumbs from which the water has been drawn off has many voids in its structure that are not made of rubber. These non-rubber voids are the voids between the particles of the rubber crumb and not the mapillary structure of the crumb particle.

By choosing a screw arrangement such that the first pressure screw is connected to the feed screw a slight compression of the total volume of the Kautschukniasse caused, which is continuously fed to the press these hollow parts, which are not made of rubber, can to a considerable extent within them only slightly compressed rubber mass can be closed. Due to the continued pressurization this chewing material as it moves through the drainage device the water is pressed out of the rubber compound. At the preferred efficiencies the screw arrangement these are not made of rubber existing voids within the entire mass in

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transformed into a capillary or macrocapillary structure. Thus, when the dewatered mass leaves the press, the same has a porous structure which is favorable for the Evaporation of the water is within a relatively short period of time.

The non-rigid elastomers dewatered in the device described here can be comminuted in a conventional comminution device or the same granules in the form in which they emerge from the device can be fed to the hot-air dryers, so that the capacity of the hot-air dryers previously used by 50- 100 7o is increased.

The device enables the reduction of the "Vassergehaltes various non-rigid iSlastomerer on 50-20 yo moisture content in contrast, .to // Erten 25-55 #" as achieved in the current bekannten..Einheiten · This v: .. A current decrease in the moisture content requires as such an increase in the capacity of the hot air dryer connected to this device. Furthermore, the use of the rotating conical element in combination ... with a

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direction to maintain the porous structure of the compacted Elastomer when it emerges from the device. Bs it results s & with that this open Structure enables effective heat transfer through the entire mass of blastomeres in the hot air dryer, thereby improving the efficiency of the unit.

As an example, it should be noted that a conventional hot air dryer for synthetic rubber has a working capacity of 1140 kg / h. Through the Application of the dewatering device according to the invention before the hot air dryer is an average capacity 228 kg / h possible over several months. Since the installation deco of the device according to the invention only 1/4 or 1/5 of the installation cost of the application Hot air drying device is the economic Aspects offensive that are characterized by the Arrangement of the device according to the invention in front of the hot air dryer result"

In the following the drying unit of the invention.

MAESSEN apparatus described, which carries in dep FIG. 1, the reference numeral 25 and ι in detail in FIGS. 4 to 10 _t is shown ..

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The dryer has a feed holder 24, which is connected to an entry opening 64. Dehydrated material is guided by the screw conveyor 65 on a cell 66 in a drum 67. the • felle is set in rotation by a motor (not shown) via a corresponding gear 68, find ϊϊίβ usual bearings and seals at every end of the globe Use. The VJeIIe rotates axially within the Drum 67 that has no perforation.

In the deep water unit, the upper part of the rocknunos unit carries several tendons 69, 70, 71, 72, 73 , etc. Between each individual tendon canal there are inwardly extending bolts 77 which have roughly the same function like the knife bars 34 in the drainage unit. The drum is preferably provided with steam chambers 48 (Mg. 7). At the left end of the drum a dispensing mechanism is provided, which is described in detail below, but which has a standing die '79 with dispensing opening 80 (FIGS. 6a, 8 and 9).

.ixe in particular in the cut; looks at and in the enlarged. Scale executed IPi ^. 9, the otand-

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Die 79 provided with a hole to make a smaller To result in an outlet opening that has shoulders 81a and 81b, which are used to hold the die insert 82 to serve. This allows matrices of different opening diameters and shapes are exchanged,

In the operation of this device, the drained flows Elastomer coming directly from the dewatering device described above, continuously into the Container 24, through opening 64 and then into the feed screw 65 a. The elastomer is slightly compressed in this feed screw and via the first bolt area in the compression screws 69, 70 etc. introduced. The 'pitch of the first compression screw 69 is preferably smaller than the pitch of the Feed screw 65. The first compaction sonic corner further compresses the elastomer in that it is pressed into the compression screw 70 via the second pin area. The compaction screw 70 further compresses the elastomer in that it is pressed over the next bolt area into the compression screw 71 with a reduced pitch. During this operation, the elastomer is exposed to the heated walls of the housing of the device.

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For most elastomers it is preferred that the steam jacket and the housing be steamed under a pressure of 14 to 17 »5 kg / cm heated. For certain Elastomers, a lower or higher pressure may be used. The elastomer is not only used in the first components of the press by means of the steam jacket heated, but also by the rotation of the compression screws through the elastomer mass. The device is preferably operated in such a way, and the pitch of the compression screws with the bolt is arranged in such a way that the build-up of the mechanical pressure that is applied to the elastomer is always greater than the vapor pressure of the water contained in the elastomer, so that the water is kept in liquid form. Consequently ; If the temperature of the elastomer rises above the boiling point of the water, sufficient pressure is created by the device built on the elastomer so that no noticeable leakage of water as water vapor during the Compression occurs in the device.

The section on Vor-r direction immediately below the feed opening 54, as shown 'in FIG. 6, in the form of a perforated Ab-GC.-center 33. The combination of the dewatering device

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and the co-operating drying device operates on the assumption that the dewatering device reduces the moisture content of the elastomer to values of 5-20%. In such humidity levels adequate compression pressures may be exerted on the elastomers within the drying apparatus dmrch the delivery of the water contained therein can be prevented at the temperatures of the drying process "If the moisture content of the continuously fed to the drying apparatus elastomers for any reason is greater than about 20% , The first Verdichtungsöhneckeη tend to set free from the elastomer to be compressed of the water. This water "can then flow in the opposite direction to the elastomer and can be discharged from the drying device through the perforated section 63. This is not a common mode of operation, but the drainage area is provided in the drying device so that the eventuality is also taken into account proper work in front of the drying device could lead to extraordinary difficulties.

The elastomer is soaked through the drying device by means of the remaining compaction without corners

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led that the temperature of the elastomer and the water contained therein is constantly increased. Simultaneously the mechanical applied to the elastomer Pressure increases and so far above the vapor pressure of the water contained in the elastomer with increasing Temperatures during passage through the device held.

By rotating the sealing screws at a relatively high speed, so that they work with a volumetric efficiency preferably in the range of 10-25 fo , but with a range of 5-4-0 fo , electrical energy can be converted into heat energy Weyden, so that the elastomer and the water contained therein is given poor. The relatively high speed of rotation of the screw flights not only enables the elastomer to be heated quickly, but also enables the elastomer to be vigorously kneaded as it passes through the device. By using various pins 77j, which may be in two, four or even six segments of the drum, the elaatomere is prevented from rotating with the shaft, thereby continuing the relative movement of the elastomer with respect to the drum

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different compression screws and thus the efficiency of the heat transfer is improved.

Through the procedure and devices described here, the temperature of the elastomer and the inside 7 / ater contained brought to a maximum value immediately in front of the dispensing opening 79. The elastomer with his Water content then occurs through the die openings of the plate 79 in such a state that the The temperature of the water formed is significantly above the boiling point of the water, but the pressure applied is so high that the water is still liquid. .At the exit from the die openings into the outside air under normal pressure or an atmosphere maintained under negative pressure At the elevated temperatures, the water evaporates immediately and emerges from the elastomer. At this moment Conversion of the liquid water into steam takes place a momentary cooling of the elastomer, since the water and the elastomer absorbs the latent heat with evaporation of the Of water. Furthermore, the escape of water vapor from the elastomer leads to expansion and formation a porous structure, which results in continued evaporation of the water as long as Moisture content of the elastomer practically complete

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- 31 has been removed.

During the Au-stride out of the opening 80 in the standing die is the elastomer by means of the cutting elements 84 (Fig. 8) in pieces with dimensions from 0.254 to 3.18 mm thick cut.-The size of these pieces is of course ultimately determined by the number of pieces in use coming cutting elements and / or the number of revolutions of the cutting mechanism and the die openings certainly. The very small bits or slices of the Extruded pieces also allow the immediate and momentary escape of the 'water vapor from the material.

It was warranted that by keeping the water content of the elastomer in the liquid state during the movement of the elastomer through the "device, a major heat- I Transfer coefficient achieved in this device! can be. For example, different tests that! with drying various types of synthetic rubbers, have shown that the heat transfer coefficient of 2JO can be achieved with the device according to the invention can. This coefficient is two to three times the value normally found in mechanical units for drying elastomers, the relative

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have low specific heats.

Duron Maintaining the water content of the elastomer in the liquid state during the temperature increase, the possibility of overheating is also greatly reduced of the elastomer either on the wall of the housing or on the surface of the screws and shafts of the Device enters. By keeping the water in the liquid state and increasing the temperature of the water and of the elastomer to the dispensing temperature, the period of time during which the elastomer is at this continues to be The temperature is kept extremely short and practically not measurable. If, as is the case with other mechanical devices for drying rubber is, which allows moisture to evaporate from the blastomer while the elastomer is passed through the device the elastomer continues to heat up, so that the period of time during which the elastomer is held at elevated temperatures is dur'ohaue noticeable

and ^ omi ^ '- a social influence exerted on the elastomer will.. ·'

In certain cases it can be advantageous to use a low ^ Amount of air, water vapor, inert gas or excess

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pump heated steam into the device according to the invention in order to reduce the porosity of the device to enlarge dispensed elastomers. It may even be beneficial to use a certain amount of steam or overheated Introduce water vapor into the device so as to take all of the heat introduced into the processed Jiilastomer to increase. In order to achieve the introduction of the gas or the vapors into the device according to the invention, is a valve, as in the .iig. 6A, 10 and 11 shown, through the wall of the unit instead of one of the bolts (lü) introduced. This valve unit is special Valve that replaces a bolt. The valve stem and seat are designed to allow locking of the go Valve prevents any backward flow of material into the valve.

The housing 91 is made hollow and provided with a threaded cap 94 at the outer end. A valve stem 95 is arranged concentrically within the housing 91. This valve stem has an iwischenge it assigns a threaded part 96, which is screwed into a bore 97 of the housing. The valve stem jumps outward from the threaded part 96 through a suitable opening in the Cap 94 in front and is at its extreme end with a

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Handle 98 is provided. The seal 99 is under the Cap 94 arranged so that the shaft 95 with respect to the Bore 97 is sealed. The valve 90 waffles a housing 91 with a threaded portion 92 which is so adapted is that the same fits into the threaded holes in which the bolts 77 are present. The housing 91 also has an unthreaded part 93 that extends inward extending over the inner circumference of the drum.

The valve stem 95 is diametrically rearward on it directed part is tapered and provided at its üinde with a frustoconical closure part 100, which in corresponding Way into a frustoconical valve seat 101 (Fig. 11) is fitted. A small cylindrical one The plunger 102 extends koachsiai in the valve closure part 100 and is narrowly shaped into a small cylinder Bore 103 fitted into the innermost hole of the housing 91. The fit between the small piston 102 and the bore 103 is preferably designed such that when loosening the Ventilschluasee 100 by turning the Handle 98 a pressurized water vapor the piston 102 past into the drum 6? be pressed in can, ^ edooh thereby the processed material not can easily enter the housing 91.

- 35 109813/1361

In the device according to the invention, various types of synthetic rubbers, natural rubbers, reclaimed rubbers and various non-rigid elastomer copolymers have been dried according to the method according to the invention 265 PS can be processed, whereby the temperature of the rubber when it is dispensed from the device is 130 G. With the momentary evaporation of the water from the polymer and rapid cooling of the polymer after leaving the die openings of the device, the temperature of the polymer is 104 to 110 0. Mechanical drying devices of approximately the same volume content as the device according to the invention can dry 1225 kg / h with an energy supply of 350 PS when drying a conventional "synthetic" ouch. The temperature of the rubber leaving the previously known devices is 177 ° to 205 ° 0, and there is no way of cooling the xlautsC) IU ¹ I by evaporation. Thus, these prior art devices require expensive in-. This rubber should be used to cool this rubber before it is packaged in order to prevent the polymer from decomposing. The device according to the invention

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909813/1351 _mftDlrt

ORIGINAL

enables non-rigid elastomers to be dried using less energy and thus cheaper operating costs. Furthermore, the temperatures of the elastomer not only do not reach when processing according to the invention the temperatures that prevail in the previously known "devices, but the momentary cooling of the elastomers represents a species-specific feature of the device according to the invention.

It is also · economically advantageous that the Capital investment for the device according to the invention is approximately half to 1/4 of the capital investment, as it is necessary per ton of processed material according to the state of the art.

Furthermore, in addition to the dewatering and drying of the non-rigid elastomers, there is also the strong one Knead through the elastomers during the passage the inventive device a homogeneous mixing other components with the "blastomeres during processing enables or one thereby the degrees of dispersion additional and previously added to the elastomer Components can increase.

- 37 -

S09813 / 1361

U54801

Due to the high heat transfer coefficient that can be achieved with the device according to the invention, there is an easy way of controlling the temperature of the product. It has been found, for example, in the processing of various elastomers, that 20 - 35 ° of the amount of heat required to raise the temperature of the elastomer, as well as increasing the contained water to the appropriate temperatures for the vaporization of the same, through the steam jacket It thus follows that when a synthetic rubber, for example an copolymer of butadiene and styrene, is dried at a controlled temperature of 143 ° 0, a thermal element 105 can be inserted into the standing die 79 (FIG. 8) of the device . Since the steam jacket of the device is not in the heat transfer with this standing matrix, this standing matrix indicates the temperature of the elastomer. By means of a control device 106, which in the J? Ig. 8 is only shown in outline, the temperature of the elastomer, as determined by the thermocouple, controls the steam supply to the steam jacket of the device, so if the temperature tends to drop above a value of 143 ° 0 », the steam pressure is automatically set in the steam jet is decreased, on the other hand the temperature increases

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909813/1351

tends to drop below 14-3 ° O, the vapor pressure elevated.

As stated above, it has been found that the various blastomeres require the use of different sizes of o and matrices in the dispensing opening 79. However, these openings are now typically 12.7 to 6.35 in diameter. In the same way, it is preferred that the core thickness of the otand die is smaller than the diameter of the opening. It has also been found that there is an optimal capacity per standard die opening for any size and thickness. However, there is an ICapacitance range on both sides of the optimum value within which an effective operation of the device is possible. _; ei a specific ^ ■ lastomereu be optimal / alues for 77 kg / found mni for 7 hours at an opening of 6.35. However, capacities that are 25 / "up and down from this optimal; ert mark are also possible Selection of the suitable diameter and number of the standing dies can be determined by the drying device

- 39 -

909J43 / 1351 ^ ad original

U54801

energy supplied maintained at a smallest possible lert and maximum utilization of e ^ to en leads 7 / ärmeenergie be obtained from the steam jacket.

In addition to the circular standing matrices, other shapes of such matrices can be used; a circular opening gives the extruded rubber the largest outer surface per unit of extruded rubber. In some cases, however, it may be preferred to use a single-slot standing die using a number of slots, e.g. 4.75 x 25.4 mm or a single slot of a larger length. Although a slotted opening a smaller surface area per - gives ^j nit strartjgepreßten lia itschu> as a circular opening, a schlitzförslge opening allows a smaller ^, aerscUnittsfläche the extruded.

The orientation is not on the specific device limited, as explained in the accompanying drawings is. In the case of de ία .drying process, however, the ! Deujperature of the Jlasto: aerate continuously and quickly a selected end temperature under such conditions be brought so that the contained in it. / water during

40 -

909813/1351

of the compaction in the drying unit is kept in practically liquid form, and the same is not the case the illastomer exits until the elastomer exits the outlet opening of the Trοc Im ution unit

Patent pending marriage

909815/1351

Claims (1)

Claims 1.1 Procedure for practically complete removal all ./assorspuron from a water containing ends, not rigid elastomers, characterized in that the elastomer is gradually passed through an elongated container increased pressure is applied to the moving elastomer, gradually increasing the temperature of the elastomer is increased and then suddenly the elastomer from the zone of highest pressure in the container in a Zone of reduced temperature and pressure can step outside the container, so that a momentary rapid evaporation and cooling occurs. 2. The method according to claim 1, characterized in that a substance such as V / water vapor, gas and vapors in the elastomer guided through the container is pressed in. 3. The method according to claim 1, characterized in that the pressure within the container is kept sufficiently high to prevent the entrained water from evaporating while the elastomer is in BADORiGINAt Container is located, whereby the temperature inside the container increases above the normal boiling point of the 7 / assors as a result of which a high thermal transfer coefficient is maintained within the elastomer. 4. The method according to claim 1, characterized in that the temperature of the elastomer is determined immediately before it emerges from the container, and the temperature of the same in the container is controlled ¹ on the basis of such a determination. 5. The method according to claim 4, characterized in that the control of the temperature partially by the Heat application carried out on the wall of the container will. 6. Drying device for carrying out the process according to any one of the preceding claims, characterized in, that it has an elongated sylindex ^ shaped Drum with a loading end and a delivery end, an opening receiving the elastomer on the loading delivery, closure parts at the delivery end with adjustable Having openings, there is a shaft rotatable in the drum which has a series of screw flights for movement - 43 - 909813/1351 of the material from the infeed end to the discharge end and for the increasing pressurization within the drum has in the direction of the last'omer movement, whereby the temperature in the jiilastomer is also progressively increased, and the outlet openings close a Sehnellverdampfen ■ the 7 / water from the elastomer with simultaneous pressure and temperature drop on exit of the elastomer out of the openings. 7 » Device according to claim 6, characterized in that an additional arrangement is provided which changes the operating temperature of the elastomer in the drum. 8. Device according to. Claim 7> characterized in that this additional device consists of a steam jacket consists. 9. Apparatus according to claim 6, characterized in that? a cutting device is provided closely adjacent to the closure part, which acts on the emerging material so that the same in pieces of limited size 3 ^.: .rle.it \ 7i:? d. - 44 - 909813/1351 ^ * ⁰ ORIGINAL 10. The device according to claim 6, characterized in that let the introduction device for introducing water vapor is provided in the drum. 11. The device according to claim 6, characterized in that that a device for determining the temperature of the elastomer emerging from the outlet openings and furthermore a device for the control of the temperature of the elastomer in the drum on the basis of such Temperature determination is provided. 12. The device according to claim 6, characterized in that that a device is provided for selectively changing the size of the outlet openings, the same consists of exchangeable standing die inserts. 13. Device according to. Claim 6, characterized in that that the drum is elongated from a circumferential arrangement There is drum rods that run parallel to the drum axis and are arranged closely interlocked, the inner ones coming into contact with the elastomer Surfaces of at least some of these drum bars are provided with longitudinal recesses, so that the elastomers moved through the drum by frictional sliding - 4-5 - 909813/1351 _E. , Dor «L movement lengthways and kneaded over these recesses 14. Apparatus according to any of the foregoing Device claims, characterized in that the first container has a cylindrical wall with openings, and the second container has a cylindrical wall without has openings. 15. The device according to claim 14, characterized in that that a device for injecting a substance such as water vapor, gas or vapors into the elastomer in the second container is provided. 16. Device according to one of the preceding device claims, characterized in that a rotatable bore is axially arranged in the container and a conical throttle piece is provided at the dispensing end of the device, 1?. Device according to claim 16, characterized in that the conical throttle da3 has a conical ülndteil, is going adjusted so that the same may be what be7 £ -._ t in and out of the opening thereof, un as an annular opening - 46 - 909813/1351 U5A8Ö1 around the end part, wherein the annular opening can be changed adjustably by the axial movement of the conical throttle. 18. The device according to claim 17, characterized in that the throttle device can be rotated together with the shaft and can be moved on the same forwards and in opposite directions, and the container and the throttle device carry cooperating fixed and movable cutting elements which "intermittently" with one another .Cutting action occurs while the vVelle is rotating. 19. The device according to claim 18, characterized in that that a device for performing a compensatory adjustment of the movable cutters is provided is, so that the cutting engagement with the fixed cutting element is always maintained when the Throttle axially on the »Velle for the purpose of changing the ring-shaped Opening is moved. 20. The device according to claim 16, characterized in that the pitch of the tendon length decreases from the J3schickun _ö send to the delivery end Lin. - ORIGINAL BATHROOM 909813/1351 ~ ~ "