IL31470A - Process and apparatus for the polymerization of olefins - Google Patents

Description

Process and apparatus for the polymerization 29733 The catalytic polymerization of olefins such butylene and the like in the gaseous phase has the as compared with the hitherto predominantly used operating methods in the liquid that the expensive processing redistillation of the solvent used is no longer Several processes for the catalytic polymerization of ethylene propylene in the gaseous phase have been In these processes the catalyst as well as the solid polymer thereby formed are in one or several in a state of eddying by the olefin or olefin mixture to be polymerized and possibly a further gas serving as a In the the gas or mixture will be referred to as a The eddying of the polymer particles may be either a comparatively dense eddying or a comparatively loose eddying With a dense eddying layer polyolefin particles which flows are fluidiaed by a carrier the gas in bubbles or streamlets through the vigorously agitated and possibly jolting eddying This state is as a rule referred to state of an eddyin layer can be compared to a boiling liquid the carrier gas seemingly forms the dispersed analogous to the vapour bubbles in the Against this in an eddying suspension the individual particles can be regarded as the disperse phase since they are dispersed in a comparatively low concentration in the oarrie gas and are therefore able to move practically independently of each This state is referred to as The German patent specification and patent specification disclose processes for the of gaseous olefins in a dense eddying layer wherein the catalyst is introduced into a zone near the bottom through a dipping tube and the excess of polyme collected at the top level of the eddying layer through an overflow and fed to a subsequent reactio heat of reaction can be dissipated In addition or instead the indirect direct cooling may be resorted in which case the carrier gas or a partial stream thereof is cooled before its entry into the eddying The German patent specification describes an eddying reactor for olefin polymerization in whic the eddying of the polymer particles caused by the carrier gas is enhanced by means of a stirrer which feeds the particles onwards In the direction of flow the carrier gas A process for the polymerization of olefins in an eddying suspension has been described in specification In this known process a chromium oxide catalyst is kept by the carrier gas in a state of eddying suspension within a reactor ope at the The coarse polyme formed drops from the against the direction of flow of the carrier into collecting chamber from which it is continually off for further polymer detached from catalyst by means of solvents and the catalyst returned to the The drawbacks of working In the liquid phase are thus merely shifted to a later stage of the The advantage of the polymerization olefins the as compared with the polymerisation in the liquid phase in presence of a is considered to reside in the fact that the recovery and processing of the and especially the complete removal of the solvent from the are In order that this advantage reall exploited it is necessary to Keep the catalyst concentration in the product so low that the final product need not be purified by the removal of the costs of such removal would nullify the advantages of the polymerization in the gaseous In the known processes for the polymerization of olefins in the gaseous phase it is extremely difficult to discharge from the reaction chambe such polymer particles onl as do no longer contain any reactive In operation with a dense eddying the polymer particles be kept rapid movement in order quick circulation and mixing thereof prevents the classificatio of the particles which would form layers and zones having a high catalys By a good mixing of the polyme particles of different sizes and catalyst concentration liberated heat o reaction can be efficaciously dissipated whereby local overheating is Such overheating would entail the agglomeration of if the temperature rises above the softening point of Such enlargement of not caused by the polymerization further slows down the dissipation of heat and finally brings the process to a occurrence of a classificatio of the particles by grain size in the eddying layer as a the result region of the highest gas It can it he achieved with th shape and of the polymer particles Nor ca these difficulties be avoided in operation with a eddying It is known that no classification by grain size occurs in eddying suspensions freel floating in a conical reactor chamber and that even particles of the eddying suspension are discharged oppositely to the direction of flow of the carrier if their velocity of fall amounts to not more than half the velocity of flow of the carrier gas at the narrowest of is impossible to prevent tha even small particles rich in catalyst are separated from the eddying The eddying layer the one and the suspension on the other do thus not fulfil the conditions for the polymerizatio of olefins in the gaseoue It has now been accordance with this that the sharp separation of a narrow fraction of coarsest grains from a of granular solids having any desired grain size distribution and being maintained in an eddying state by a carrier gas can be effected by the selection of appropriate the state of a comparatively dense eddying layer is maintained in the upper part of an eddying and a state a strongly loosened eddyin suspension in the lowe part of the in that steep of the Velocity of flow of the carrier gas is produced between these two zones of the can be done in such a manner that in the facial zone between these two states the Velocity of flow of the carrier gas i increased by a constriction of the to extent tha it reaches the velocit of beginning onward transportation and thus above the velocity a which the coarser particles The invention consists in a process for the catalytic polymerization or of Or vaporized unsatura ed hydrocarbons or their wherei catalyst and polymer are maintained in the eddied state b a carrier gas containing the and the polymer which has grown a coarse granulate is discharged from the process according to the invention is characterized in that a granular polymer and the catalys are maintained by the carrier gas an upper of the realtor at a large section of flow in a state of a eddying and in a lower zone of the reactor at a narrow of flow in a state of a loose eddying that in the interfacial between these two zones the velocity of flow of the carrier gas is increased by a constriction of the of flow above the velocity flow in the zone of the eddying and that coarse polymer particles are discharged from the zone of the eddying accordance with the invention the velocity of flow of the carrier gas is in the interfacial between the upper dense eddying laye and the lower suspension by a constriction the flow above the velocity of flow in the region of the eddying and this to at least times the velocity of flow in the eddying By a particula embodiment of the invention the curren of carrier gas is in the region of the narrowest a plurality of partial streams of slightly decreasing the sum the narrowest of all the sor tubes amounting to not more than time the i the region of the eddying Preferably these partial of the carrier gas indirectly cooled by a coolant of low boiling point kept under a variable From th region of the eddyin suspension a partia stream the carrier gas ca be from a point below the interfacial leading to the dense eddying and be in or in into region the dense eddying suspension above the interfacial a partial stream deflected from the region of the eddying suspension may be in whole or in to the carrier gas fed to the By these measures the velocities of flow within the two regions of the eddying states can be varied within wide limits independently of one A reactor suitable for carrying out the process of this invention may for two ly superposed cylindrical shells of which the upper one has a larger diameter than the lower ratio of diameters of the shells is about to preferably to At their adjacent ends the two cylindrical shells may be connected to each other by a simple annular the connection is designed as a conical intermediat section in order to avoid dead angles in which solids can be As usual with eddying reactors the carrier gas is introduced at the bottom end of the lower cylindrical shell through a grid o the and withdraw at the top end of the possibly after passing a In accordance with the invention constriction is disposed the upper the lower shell whereby the velocity of flow of the carrier gas so that at this place obtains the highest velocity of flow the This Constriction of the may be for by a perforated plate or a ooncentrically disposed inse free should amount to at most time the of the lower cylindrical The of the perforated plate preferabl dimensioned that their diameter amounts at least 5 to 20 times the diameter coarse grains to be In the case of a concentrlcal inset the annular gap formed between the latter wall of the shell should have a width o at least 2 to 10 times the diameter of the coarse grains to be These ranges of dimensions are given as a general only and ma be downwards or in individual The shape of the grains and the structure of the grain on which the flowing characteristics of grain mixture largely dependen considerably influence the dimensioning of these The concentrlcal inset may be connected to the reacto by means of radial It may have a conical or Conical and can be disposed on a vertical rod along the of the By another embodiment of the invention the Garrler gas current is subdivided in the between the eddying layer and the eddying sus ension a reat number th velocity of flow is increased to least time the velocity in the region of the eddying In this em odiment the dissipation of the heat of and accordingly the control of reaction temperature can in an especiall advantageous manner in that diffusor tubes are surrounded by a cooling jacket which contains a coolant such as pen heptane or the By the adjustment of the pressure in the coolant with aid of a regulating valve the desired temperature can be kep constant with a margin of less than The dissipation of the heat of reaction through the wall the diffusor tubes has the advantage in relation to the volume of the reactor there exists a comparatively large cooling The dlffusors are advantageously disposed in a common cooling Above and below the zone of the narrowest reactor section the reactor may have openings which communicate with Through these fractions of the carrier can be withdrawn from the reactor or be introduced into the In a part of the reactor medium can be withdrawn upstream of the constriction of the from the lower reactor zone and be introduced into the upper reacto zone downstream of the In the process of olefins according to the invention in an eddying laye and an eddying suspension created within the same carrier gas an efficacious transfer of heat of reaction to the gas in the upper eddying and possibly also to the reactor wall which is preferably surrounded b a cooling owing to the intense eddying and mixing the catalyst and polymer maintained a e of eddying suspension at a section of flow and a correspondingly higher velocity of flow of the carrier In this the carrier gas has a velocity of flow of to 10 times the velocity of eddying of the coarsest polymer particles and it exceeds the velocity of of the particles by 2 to 10 At this high carrier gas velocity all the fine particles are entrained by the carrier gas current the lower zone and returned into the eddying layer in the upper Owing to the hig relative velocity of the eddying suspension the coarse particles undergo mutual friction whereby superficially adhering amounts of catalyst are The matter thus off is returned into the eddying layer of the upper zone together wit ther fine In the eddying where the greater of the velocity of the carrier gas decreases so much that no substantial amounts of fine grains are entrained out o the In the zone the eddying suspension collect the coarser particles which the activity of the catalysts still contained therein finally exhausted during while these further dwell in the eddying This makes it possible discharge from the lower zone of the reactor a polymer having a uniform and desired grain between about and about 5 and so low a residual catalyst content that this can be neglected in the further The particle size obtainable in the process depends on the time dwell of the polymer particles i the reactor on the type of catalyst The constriction of the between the upper and lower zones the reactor forms a boundary or interfacial zone between the states of the eddying layer and beha iour of eddying layers on the one hand and of eddying suspensions the other hand has been known it could no be foreseen that by introduction of such a constrictio of cr an eddying suspension and an eddying layer could be disposed in superposition in the same carrier gas current and in a The process according to the invention can be carried out with all the catalysts suitable for chromium deposited on an oxide or silicate material for the polymerization of combined catalysts of or th type are preferred for the olefin The catalysts are introduced into the zone of dense eddying layer in the upper reactor through a dipping tube or with a partial stream of the carrier or as solution or suspensio in a readily volatile In operation with combined catalysts component may be into the carrier gas or a partial stream carrier gas may consist of the gaseous vaporous monome or o be and it may in contain an inert The monomers not consumed in the reactor are returned into the reactor by a conventional carrier gas this circulation monomers consumed b polymerisation arc up by the supply of fres For removal of impurities a partial stream of the carrier gas ma be diverted from the circulation and Outside the reactor the circulating gas conducted through a cooling system in which carrier gas is freed from the heat it has take with it from the The process according to invention can carried for 100 atmospheres For the dissipation of the excess heat of reaction from the reactor a readily evaporating pe hexane or the may be injected into th eddying laye in the upper vapours of this direct coolant are removed from the circulating carrier gas by condensation in cooling For the additional dissipation of heat of reaction the reactor may be provided with a cooling The highest temperature of the circulating containing leaving the reactor should not be above the softening point of the The process of the invention is suitable the izatio of olefins such as of diole such as butadiene and and olefin derivatives as vinyl acrylic acrylonit by themselves or in any desired i being also possible to eopolymerlze one o several of these with compounds such episul and epii The invention is illustrated with reference to the accompanying drawings which by way of a reactor and its for carrying out the process of the as wel as a diagram of the complete t 1 is a partly axial of a reacto 2 is a thereof on line of a fragmentary elevation o another reactor having a modified design o the interfacial section between the upper and lower 4 shorts similarly ye another modified of the in 5 is a on line of shows similarly yet another modification the reacto 7 is a flow sheet showing a complete apparatus for carrying out the process of the including a according to the carrying cut the process one ma for a reactor illustrated in 1 and The gaseous olefin or the carrier gas is introduced through a connection 1 into a pressure chamber 2 and flows from there through a perforated bottom 3 known a a bottom or a porous plastics into a cylindrical The cylindrical consists essentially of three superposed 6 of different The shell has at least one outlet tube 7 for the withdrawal of the unreacted carrier at least one Outle 8 for discharging the polymer one or connections 9 for introduction of lower cylindrical section 4 has a height ratio as a between and In it there collect the coarsest polymer particles which are maintained by the rrier gas in a state of eddying In the upper part of the lowermost cylindrical section 4 there is according to the a constriction 3D of the case of 1 and is designed as a perforated or tubular The diameters of the passages 11 of the plate should amount to at least times the diameter of the polymerized particles to The The aggregate of the passages of the plate 1G is so chosen that the velocity of carrier flowing ou of the lowermost reacto section 4 is increased within the passages 11 than She velocity of the carrier gas within the passages as a be greater than the velocity of migration of the largest polymer Above the narrowest by the perforated plate 10 there disposed a conically flaring section 12 which merges i tp the cylindrical section where the mixture of catalyst particles and of particles of the polymer formed is brought by the carrie gas into a state of a dense eddying The ratio of the upper rical section 5 may be chosen between and or even One or more catalyst feed connections 9 open into the cylindrical section The carrier gas not reacted in the eddying layer flows through a conically designed transition zone 13 into a rical settling chamber 6 in which fine whose velocity of fall is greater than the further diminished carrier gas are The carrier gas leaves the reactor through the tub 7 disposed in the lid In order to start the operation of the granula matter which as a rule consists of the polymer to be may introduced the reactor through the connection 15 leading chamber discharge of the product is suitably effected throug the pipe which is controlled by a conventiona off member a gate wheel into or a gate For the dissipation of the heat of reaction or an adjustment of a desired temperature the surrounded by cooling jacket 17 which has at least one connection for the introduction of the coolant and at least one connection 19 the discharge I order that with a reactor of given dimensions the grain the coarsest polymer particles to be separated can be it is necessary to a possibility varying the amounts Of carrier gas respectively present in the zones o the eddying layer and the constriction of the independently f each This can be for in such a wanne as illustrated in a portion of the carrier gas is into the below or the constriction through annular slots 21 o by some other appropriate For this purpose there are provided connections 22 and 23 and an annular space whose two sections 24a are separated by an annular is also possible to withdraw om the reactor a portion carrier gas the latter enters the perforated plate the embodiment of the invention according to 4 and 5 the constriction of the between eddying layer and the eddying suspension zone is designed in the form Of parallel dlffusor 30 which the gas flowing out of the the eddying suspension into plurality of partial streams which are reunited in conical section 31 of the reactor above the sor The diff which out conically below their narrowest waist and then into a cylindrical par fixed at their bottom to a plate and at top ends to a plate embodiment is especially useful in where strong cooling has to in the polymerization of case the diffusor tubes are surrounded by a jacket 32 through which a coolant boiling point or a liquid is At least one connectio 53 is provided for the introduction o the coolant and at least one connection 34 for the withdrawal of the By an intense mixing of the polymer within the diffusor tubes and especially efficacious dissipation of the heat is by the noxious overheating o the which could lead to the formation of is Below the diffusor tubes a tapering section 58 is preferably provided in the transition to the eddying respects this reactor to according to and 6 shows a further embodiment of the reactor the constrictio of the is by an 40 disposed concentrically with the reactor between the cylindrical section 4 and the conical transition section In this embodiment the concentric inset is disposed at upper end of a rod 44 which is guided in a sleeve 46 and can be reciprocated vertically in the axis the cylindrical with a conical shifting of the rod 44 is effected by means of a lever 42 pivotin about an axis By thus shifting the rod the of the annular passage 45 can be modified without interrupting the whiO enables a certain control of the amount and particle size of the polyme grains migrating from the eddying layer into the eddying A complete apparatus for the polymerization of ethylene in The reactor which is essentially the same as the one shown in 1 and has in its central section 51 a dense eddying layer by catalyst particles and polymer in which the main polymerization reaction takes The carrier gas containing the monomer to be polymerized enters in the bottom part the reactor into the pressure chamber 52 and flows through the perforated bottom 53 into the cylindrical reactor section where it in a strongly loosened suspension the polymer particles separated from the central section In the perforated plate 55 the velocity of the carrier gas raised to the magnitude of the velocity migration of the coarser particles in accordance with the of the reactor into the eddying layer and an eddying suspension Coarser particles fall through the passages of perforated plate 55 the eddying layer 51 downwards into the eddying suspension 54 while the fine particles are returned by the carrier gas from the eddyin suspension zone into the eddying Above the perforated plate 55 there is an annular slot 56 through a portion of carrier gas is introduced via the conduit 57 into the conical transition section of the This makes possible to regulate within certain limits the amount and particle of thecoarser particles migrating out of the eddying bed The amount of carrier gas fed through annular slot 56 is by a gate valve The powderous catalys is fed from a supply container 60 by a dosing device through the feed connection 62 the reactor The volatile component of the catalyst is aspirated by a dosing pump 63 from a storin container 64 and injected into The carrier gas not reacted in the eddying bed flows through a conical transition section into the wider upper part 67 of the reactor where the entrained solid particles are to the diminishing velocity of the The gas at the lid 68 and conducted through a conduit 69 a duet filte 70 any dust particles still present in the are Subsequently the carrier gas is cooled to its temperature by a cooler the separation of any volatile of the catalyst condensed by the for the cooling of the coolant inflected into the a separator 72 is provided where the condensed liquid is collected and which is returned into the store container By a compressor the cooled gas again pressurized and returned to the The amount carrier gas can be regulated by a valve The consumed monomer made up by fresh feed by means of a pressure regulating 75 through the conduit this plant the dissipation of the heat of reaction mainly effected by the carrier whose temperature entry into the reactor is in dependence on the reaction measured by a thermometer by of a control valve 78 and a heat exchanger For the additional direct cooling a readily volatile may be injected into th eddying layer through nozzles provided in the wall of the eddying bed section After cooling and condensation this direc coolant can be recovered in a separator 7 coarse polymer particles formed by the which in the lower section 54 of the reactor have still an complete the are discharged into a collecting 80 container 82 through a pipe and a gate The process of the invention is illustrated by following to which it is Ethylene polymerized with the aid the apparatus illustrated polymerization reactor which has a total height of contains in the section which has a diameter of 450 an eddying layer consisting o a catalyst and of polyethylene particles formed by the The eddying layer has a about and is kept moving by the reaction gas which consists to by volume of ethylene and to by volume of which latter controls the molecular For maintainin an intensely agitated eddying 280 of carrier gas are This carrier gas is introduced into the pressure chamber 52 of the reactor through a conduit 83 and flows through the bottom consisting of a perforated metal sheet having perforations mm into the lower reactor section This section has a diameter of 200 mm and a height of 1 With a velocity of flow of the gas of coarse polymer particles are maintained in this reactor section in an eddying suspension which is strongly loosened and violently The perforated plate disposed between the lower section the conical transition section 58 and the upper reactor section 51 has 55 tubular perforations of 20 mm diameter and 75 mm 75 of granular catalyst are introduced from the supply container 60 by dosing device 61 through the feed pipe preparation of the polymerisation parte of titanium tetrachloride are in dry and degassed heptane with parts of triisobutyl then 5 parts of ethylene introduced The reaction product filtered with the exclusion of air and washed with The washed powder is slurried with heptane and in an atmosphere of intimately mixed with 50 times its weight of finely granulated polyethylene having a particle size from to and subsequently dried at C with exclusion e polymerization is conducted at a superatmoepheric pressure of atmospheres nd a reaction temperature of within the dense eddying The reaction gas withdrawn at the top 68 of the reactor and liberated from dust by means of the dust filter In the cooler 7 the gas is cooled to whereafter it is returned to the process by means of the circulation consumed ethylene is made up by fresh ethylene fed through pressure regulator 75 and the conduit For the activation of the catalyst the circulating gas is charged with triisobutyl aluminium in an evaporator 65 after having been warmed to in a heat exchanger 15 of granular polyethylene are discharged through a discharge pipe 80 which disposed in the center of perforated plate 53 and has a diameter of 60 The granulate has a white colour and the grain size distribution is shown in 1 Table The granulate an apparent bulk weight of 320 The specific weight of polyethylene is the reduced viscosity is between and 2 polymerization of ethylene is carried out as described in 1 except that 50 the carrier gas are introduced from a conduit through an annular slot 56 provided in the wall of the conical transition sectio 58 above the perforated plate f granular catalyst of the same composition as Bxample 1 are charged into the reactor throug the feed pipe The product is 20 of granular polyethylene having a white a grain size distribution as indicated n Table 2 and an apparent bulk weight of 315 Table 2 Particle Percentage up to above Ethylene is polymerized in a reactor whose constriction of constituted 19 diff sor tubes according to 4 and The diffusor tubes have a length an upper diameter of a narrowest diameter of 30 mm a widened lowe diameter of 40 Downwards the tubes open a iapering section of This followed by cylindrical section 54 of and 200 mm Above the diffusor tubes there is disposed a conical transitional section of 150 length opens into the cylindrical section 51 which has a length of 2 m and a diameter of 450 The diffusor tubes and the upper conical transition section 31 are surrounded by a jacket 32 which is supplied with pentane for cooling through a connection The vapours generated by the boiling pentane are drained by a connection For the rest the reactor designed as described Example The polymerization catalyst is a highly active type catalyst which consists of the known combination of and is supported by polyethylene of a particle size 100 300 100 gh of catalyst granulate with a catalyst conten of by weight are charged into the reactor through the dosing device 61 and feed pipe As a trlethyl aluminium is injected into the evaporation 65 by means of the dosing pump The polymerization gas consists of by volume of ethylene and by volume of hydrogen which serves controlling the molecular operation at a pressure of 20 atmospheres gauge and temperature of within dense eddying For the maintenance of an intensely agitated 3 dense eddying layer in the 51 of the 250 of carrier gas are gas is introduced in its entirety into the bottom section 54 of the reactor through a conduit 83 and the perforated bottom 53 at a temperature o regulated b the regulating valve 78 and the heat exchanger a better dissipation of heat the temperature of evaporation of the pentane boiling in the space 32 surrounding the is adjusted to 30 of white granular propylene a re discharged through the pipe 80 and the gate ita grain size distribution is as Percentag up to above The specific gravity the polyethylene the reduced viscosity 4 manufacture polypropylene ie effected in an apparatus corresponding to the one in The constriction the in the zone between the lower and upper sections of the in accordance with this is achieved in case by a concentrically disposed body 40 in accordance with which its cylindrical part has a diameter of 55 height of cylindrical section is 50 the total height of the body 100 As shown in 6 body can b displaced upper cylindrical section of the reactor contains the eddying bed has a diameter of 200 mm and a height of 1 lower reactor zone a diameter of 90 and height of two zones are by a conical transitio section additiona carrier gas is introduced in this case into the upper section of the In order to maintain a etate of ed eddying in the upper section of the 30 of propylene have to be fed to the polymerization was effected at a superatmospheric pressure of 8 atmospheres gauge and at a temperature of j continuous the spent catalyst is p by a feed of of catalyst granulate containing by weight o into the For the preparation of the polymerization commercial of the type mixed with propylene of a grain of to The mixture is admixed with heptane and for 5 minutes in an atmosphere of pure mixture is then and the heptane is evaporated by means of nitrogen bubbled through the The granula propylene had previously been boiled with hexane wit by volume triisobutyl cooled and then washed twice with and dried in a atmosphere of polypropylene should contain some ro ortio o o ro lene soluble a diethyl aluminium monochloride is pumped with the dosing pump 63 into the a evaporator 65 in such an amount that the content of the carrier which consists of up to of amounts to 2 or 3 As a of the propylene of fresh propylene are introduced into the reaction system through the regulating 75 and the conduit In continuous 3 h of polypropylene are discharged through the central discharge pipe which has a diameter of 25 discharged polymer particles have the following distribution Particle size Percentage up to above The polypropylene thus produced has a specific gravity of a reduced viscosity of and a proportion of of atactic In to start the operation a polymerizing apparatus in accordance with Example 6 litres of polypropylene granulate of a grain size of 1 to 2 mm are admixed in an atmosphere of nitrogen with hexane containing by volume aluminium and the mixture is refluxed for some The mixture is then dried at The entire apparatus then put under the operational propylene pressure of 8 atmospheres circulation of gas is adjusted by of compresso 73 through the valve to a flow rate of 30 and passed through the reactor after the granulate described above has been charged into the reactor through a special connection 15 circulating gas is heated to by the preheater 79 and diethyl aluminium monochloride pumped into the evaporator 65 by the pump 63 until the concentration thereof in the circulating gas amounts to 2 to 3 the catalyst according to Example 4 is continually fed by the device through the eeding pipe 62 into the eddying layer formed by the initial charge of polypropylene After the reaction has started the temperature of the circulating gas is lowered by the temperature the regulating valve and the heat exchangers 79 that it reaches when has got into ful For dissipation of the heat of reaction liberated in the of the polymerization the cooler 71 is also put into When the pressure drops in the system owing to the consumption of fresh gas fed into the apparatus through the prossure regulating valve By means of the dosing pump 63 only so much diethyl aluminium monochloride Is thereafter pumped into the evaporator as is required for maintaining an alkyl content of 2 to 3 in the circulating the eddying bed has reaohed double the height of the initially present bed to the formation of half the bulk of the bed is discharged through the pipe 80 and gate Subsequently the bed is to to a height of and er the continuous discharge of produced polypropylene can be insufficientOCRQuality

Claims (1)

1. CLA .S 1. A prooess for the catalytic polymerization or co-polymerization of ole inlcally unsaturated, hydrocarbons or hydrocarbon derivatives in the gaseous or vapour phase, in which the catalyst and polymer are maintained in an eddying state by a carrier gas containing the monomer or monomers to be polymerized and the portion of polymer that has grown into a coarse zone granulate is discharged by gravity from the eddying ee--e«o&an of flow in the zone of the eddying suspension. 3. A process according to Claim 1 or 2, wherein a partial stream of the carrier gas is deflected from the zone of the eddying suspension ahead of the constriction of the cross-section which precedes the dense eddying layer. 4. A process according to Claim 3» wherein the partial stream of carrier gas deflected from the dense eddying layer is introduced in whole or in part into the zone of the dense eddying layer above the interfacial cross-section. 5* A process according to Claim 3, wherein the partial stream of the carrier gas deflected from the zone of the eddying suspension is returned in whole or in part to the carrier gas current entering the reactor. 6. A process according to any of Claims 1 to 5i wherein the carrier gas current is subdivided in the region of the interfacial cross-section by means of parallel diffusor tubes into a plurality of partial streams of slightly decreasing velocity. 7. A process according to Claim 6, wherein the partial streams of the carrier gas are cooled indirectly by a low-boiling coolant maintained under a variable pressure. 8. A process according to any of Claims 1 to 7» wherein the carrier gas is conducted through the reactor under a pressure between 1 and 100 tnu gauge. 9. A process acoording to any of Claims 1 to 8, wherein the catalyst is introduced into the eddying layer and or- h© £d4y ftg-e¾u3£efteAoa in the form of a solution or suspension in a low-boiling hydrocarbon. 10. A process according to any of Claims 1 to 9» wherein low-boiling hydrocarbon is injected into the eddying layer and/or the eddying suspension as an evaporating coolant. 11. A process according to any of Claims 1 to 10, wherein the carrier gas discharged from the region of the dense eddying vertically displaoeable. 19. A reactor according to an of Claims 12 to 18, comprising annular spaces upetream and downstream of the zone of narrowest cross section, an annular slot between the upstream annular space into the zone of narrowest cross section, and an annular slot between this latte zone and the downstream annular space; and two .tubular connections in the wall of the reactor in the zones of the two annular spaces. For the Applicants DR. REINHOLD J30HN , PARTNERS