CA1249983A - HIGH PRESSURE RECIPROCATING MOTION COMPRESSOR AND USE THEREOF FOR THE POLYMERIZATION OF ETHYLENE AND .alpha.-OLEFINS - Google Patents
HIGH PRESSURE RECIPROCATING MOTION COMPRESSOR AND USE THEREOF FOR THE POLYMERIZATION OF ETHYLENE AND .alpha.-OLEFINSInfo
- Publication number
- CA1249983A CA1249983A CA000453277A CA453277A CA1249983A CA 1249983 A CA1249983 A CA 1249983A CA 000453277 A CA000453277 A CA 000453277A CA 453277 A CA453277 A CA 453277A CA 1249983 A CA1249983 A CA 1249983A
- Authority
- CA
- Canada
- Prior art keywords
- ethylene
- polymer
- fluid
- chosen
- reciprocating compressor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 title claims description 24
- 239000005977 Ethylene Substances 0.000 title claims description 24
- 238000006116 polymerization reaction Methods 0.000 title claims description 7
- 239000012530 fluid Substances 0.000 claims abstract description 21
- 229920000642 polymer Polymers 0.000 claims abstract description 16
- 238000007789 sealing Methods 0.000 claims abstract description 16
- 150000001875 compounds Chemical class 0.000 claims abstract description 10
- 229910052709 silver Inorganic materials 0.000 claims abstract description 9
- 239000004332 silver Substances 0.000 claims abstract description 9
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 8
- 239000000956 alloy Substances 0.000 claims abstract description 8
- 239000002131 composite material Substances 0.000 claims abstract description 8
- 230000006835 compression Effects 0.000 claims abstract description 8
- 238000007906 compression Methods 0.000 claims abstract description 8
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000010936 titanium Substances 0.000 claims abstract description 7
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 claims abstract description 6
- 229910001092 metal group alloy Inorganic materials 0.000 claims abstract description 6
- -1 tungsten carbides Chemical class 0.000 claims abstract description 5
- 239000004642 Polyimide Substances 0.000 claims abstract description 4
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 4
- 229920001721 polyimide Polymers 0.000 claims abstract description 4
- 239000010959 steel Substances 0.000 claims abstract description 4
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 4
- 239000010937 tungsten Substances 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 20
- 230000003197 catalytic effect Effects 0.000 claims description 7
- 239000002245 particle Substances 0.000 claims description 7
- 239000000203 mixture Substances 0.000 claims description 6
- 229910000906 Bronze Inorganic materials 0.000 claims description 5
- 239000010974 bronze Substances 0.000 claims description 5
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 claims description 5
- 239000004605 External Lubricant Substances 0.000 claims description 4
- 239000000853 adhesive Substances 0.000 claims description 3
- 230000001070 adhesive effect Effects 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 3
- 229910052739 hydrogen Inorganic materials 0.000 claims description 3
- 239000000314 lubricant Substances 0.000 claims description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 2
- 229910001018 Cast iron Inorganic materials 0.000 claims description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 2
- 239000011152 fibreglass Substances 0.000 claims description 2
- 229910002804 graphite Inorganic materials 0.000 claims description 2
- 239000010439 graphite Substances 0.000 claims description 2
- 229930195733 hydrocarbon Natural products 0.000 claims description 2
- 150000002430 hydrocarbons Chemical class 0.000 claims description 2
- 239000002904 solvent Substances 0.000 claims description 2
- 229920006395 saturated elastomer Polymers 0.000 claims 1
- 235000000396 iron Nutrition 0.000 abstract description 2
- 229920001343 polytetrafluoroethylene Polymers 0.000 abstract description 2
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 4
- 238000007334 copolymerization reaction Methods 0.000 description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000000178 monomer Substances 0.000 description 3
- VXNZUUAINFGPBY-UHFFFAOYSA-N 1-Butene Chemical compound CCC=C VXNZUUAINFGPBY-UHFFFAOYSA-N 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 239000012190 activator Substances 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- 239000001273 butane Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- IJDNQMDRQITEOD-UHFFFAOYSA-N n-butane Chemical compound CCCC IJDNQMDRQITEOD-UHFFFAOYSA-N 0.000 description 2
- OFBQJSOFQDEBGM-UHFFFAOYSA-N n-pentane Natural products CCCCC OFBQJSOFQDEBGM-UHFFFAOYSA-N 0.000 description 2
- 239000001294 propane Substances 0.000 description 2
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 2
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 150000003623 transition metal compounds Chemical class 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229940123457 Free radical scavenger Drugs 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 125000005376 alkyl siloxane group Chemical group 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- 238000005219 brazing Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 239000008139 complexing agent Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 150000001993 dienes Chemical class 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 150000004678 hydrides Chemical class 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 150000002902 organometallic compounds Chemical class 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 239000002516 radical scavenger Substances 0.000 description 1
- 229930195734 saturated hydrocarbon Natural products 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- YONPGGFAJWQGJC-UHFFFAOYSA-K titanium(iii) chloride Chemical class Cl[Ti](Cl)Cl YONPGGFAJWQGJC-UHFFFAOYSA-K 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- GPPXJZIENCGNKB-UHFFFAOYSA-N vanadium Chemical compound [V]#[V] GPPXJZIENCGNKB-UHFFFAOYSA-N 0.000 description 1
- 238000009941 weaving Methods 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
- F16J9/28—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction of non-metals
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B15/00—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts
- F04B15/06—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts for liquids near their boiling point, e.g. under subnormal pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B39/00—Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
- F04B39/04—Measures to avoid lubricant contaminating the pumped fluid
- F04B39/041—Measures to avoid lubricant contaminating the pumped fluid sealing for a reciprocating rod
- F04B39/042—Measures to avoid lubricant contaminating the pumped fluid sealing for a reciprocating rod sealing being provided on the piston
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/14—Pistons, piston-rods or piston-rod connections
- F04B53/143—Sealing provided on the piston
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
- F16J9/26—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction characterised by the use of particular materials
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2201/00—Metals
- F05C2201/04—Heavy metals
- F05C2201/0403—Refractory metals, e.g. V, W
- F05C2201/0412—Titanium
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2201/00—Metals
- F05C2201/04—Heavy metals
- F05C2201/0418—Noble metals
- F05C2201/0421—Silver
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2201/00—Metals
- F05C2201/04—Heavy metals
- F05C2201/0469—Other heavy metals
- F05C2201/0475—Copper or alloys thereof
- F05C2201/0478—Bronze (Cu/Sn alloy)
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2225/00—Synthetic polymers, e.g. plastics; Rubber
- F05C2225/04—PTFE [PolyTetraFluorEthylene]
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2225/00—Synthetic polymers, e.g. plastics; Rubber
- F05C2225/06—Polyamides, e.g. NYLON
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2225/00—Synthetic polymers, e.g. plastics; Rubber
- F05C2225/10—Polyimides, e.g. Aurum
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Compressor (AREA)
- Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
- Polymerisation Methods In General (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Sealing Material Composition (AREA)
Abstract
Compresseur à mouvement alternatif destiné aux très hautes pressions comprenant d'une part au moins un piston plongeur ou une chemise de cylindre constituée d'un matériau choisi parmi les fontes, les aciers et les carbures de tungstène et d'autre part au moins un élément d'étanchéité. L'élément d'étanchéité est constitué d'un matériau composite associant d'une part au moins un alliage métallique choisi parmi les bronzes et les alliages à base de titane et d'autre part soit au moins un polymère choisi parmi les polytétrafluoréthylènes, les polyimides et les polyimides -amides, soit un composé fritté graphite-argent. Application à la compression d'un fluide sous une pression de refoulement supérieure ou égale à 150 bars.Reciprocating compressor for very high pressures comprising on the one hand at least one plunger or a cylinder liner made of a material chosen from cast irons, steels and tungsten carbides and on the other hand at least one element sealing. The sealing element consists of a composite material combining on the one hand at least one metal alloy chosen from bronzes and titanium-based alloys and on the other hand either at least one polymer chosen from polytetrafluoroethylenes, polyimides and polyimides -amides, ie a graphite-silver sintered compound. Application to the compression of a fluid under a discharge pressure greater than or equal to 150 bars.
Description
S,~33 La présente invention se rapporte `a un compresseur ~a mouvement alternatif destiné aux très hautes pressions et `a son application `a un procédé de polymérisation d'éthylène et d'c~-oléfines.
La presente invention vise à résoudre les problèmes techniques posés par la compression, sous une pression de refoulement supérieure ou égale à 150 bars, d'un fluide répondant à au moins l'une des trois cond;-tions suivantes :
- le fluide contient des traces de particules abrasives.
- le fluide n'est pas autolubrifiant et il intervient dans un procédé n'ac-ceptant pas de lubrifiant externe.
- le flu;de n'est pas autolubrifiant et il intervient dans un procéde accep-tant des lubrifiants externes mais il est solvant des lubrifiants pos-sibles.
Le fluide concerné par le problème de la présente invention peut être à l'état liquide ou gazeux, sa température peut être comprise dans une gamme allant de -30~ à f200C `a tout étage de la machine de compression, et enfin il peut etre de nature chimique très diverse, par exemple hélium, ammoniac, éthylène, melange d'éthylène et d'au moins un composé choisi parmi less~ -oléfines, l'hydrogène, les hydrocarbures saturés tels que propane ou butane.
La compression d'un fluide sous une pression de refoulement supé-rieure ou égale à 150 bars s'effectue ~énéralement dans une machine de compression `a un ou plusieurs étages, à mouvement alternatif, dont chaque cylindre comprend d'une part un piston plongeur ou une chemise de cylindre et d'autre part un élément d'étanchéité pouvant être soit (dans le cas d'un piston plongeur) au moins une garniture statique en plusieurs parties soit (dans le cas d'une chemise de cylindre) au moins un segment mobile solidai-rement avec le piston. Dans le cas de garnitures, l'étanchéité dynamique s'effectue entre la ou les garnitures et le piston plongeur ; dans le cas de segments, l'étanchéité dynamique s'effectue entre la chemise de cylindre et le(s) segment~s~.
Lorsque le fluide destiné à être comprimé ne répond `a aucune des trois conditions énumérées précédemment, notamment lorsque ledit fluide est autolubrifiant et/ou lorsqu'il ne contient pas de traces de particules abra-sives, et/ou lorsque les surfaces en contact constitutives de l'étanchéitédynamique sont lubrifiées, la machine de compression fonctionne de manière satisFaisante pendant une durée de quelques milliers d'heures sans pertur-bations, pouvant atteindre 7 000 heures, sans qu'il soit nécessaire de choisir avec une attention particulière les matériaux constituant les différentes parties de ladite machine. Par exemple lorsque l'on comprime de l'éthylène ou un mélange d'éthylène et de comonomères polaires jusqu'`a une pression de refoulement souvent comprise entre 150 et 3000 bars, dans le cadre d'un procédé de polymérisation à haute température en présence d'ini-tiateurs de radicaux libres tel que décrit notamment dans les brevetsfrançais n 1.584.529, 2.025.887, 2.099.267 et 2.313.399, il est commun d'utiliser un compresseur à mouvement alternatif dont le piston plongeur ou la chemise de cylindre sont constitués en acier traité ou en fonte ou en un matériau de la famille des carbures de métaux comme le tungstène et dont les éléments d'étanchéité sont réalisés en bronze tel que le bronze UE 9 P con-tenant ~ % d'étain, 0,3 à 1 % de phosphore et le reste en cuivre. Ceci tient au fait que le flux d'éthylène à comprimer ne contient pas de traces de par-ticules abrasives.
Il a été constaté par contre que lorsque le fluide à comprimer répond à au moins l'une des trois conditions énumérées précédemment, un compresseur à mouvement alternatif dont les parties sont constituées des matériaux communément utilisés ne peut plus fonctionner de manière satis-faisante, c'est-à-dire sans interruption, que pendant un nombre d'heures limité `a quelques centaines, voirP quelques dizaines, ce nombre étant fonc-tion du manque de lubrification et/ou de la teneur des particules abrasivesdans le fluide. L'analyse des causes de ce fonctionnement insatisfaisant a montré, notamment par examen au microscope optique et électronique des sur-faces des éléments d'étanchéité, une usure excessivement rapide de ceux-ci conduisant inéluctablement au grippage des éléments d'étanchéité du compres-seur. La présente invention a pour objectif d'apporter des solutions au pro-bl~eme technique ainsi exposé.
Un premier objet de la présente invention consiste en un compres-seur à mouvement alternatif destiné aux très hautes pressions comprenant d'une part au moins un piston plongeur ou une chemise de cylindre constitué
d'un matériau choisi parmi les fontes, les aciers et les carbures de tungs-tène et d'autre part au moins un élément d'étanchéité, caractérise en ce que ledit élément d'étanchéité est constitué d'un matériau composite associant d'une part au moins un alliage métallique choisi parmi les bronzes et les alliages à base de titane et d'autre part soit au moins un polymère choisi parmi les polytétrafluoréthylènes, les polyimides et les polyimides-amides, soit un composé fritte graphite-argent.
Parmi les bronzes utilisables pour l'élément d'étanchéité du com~
presseur selon l'invention figure notamment le bronze UE 9 P décrit ci--dessus. Parmi les alliages à base de titane utilisables pour l'élément .
8~
d'étanché;té du compresseur selon l'invention figurent notamment les allia-ges de titane et d'argent tels qu'un alliage comprenant 94 % en poids de ti-tane et 6 % en poids d'argent. Les polymères utilisables pour l'élément d'étanchéité du compresseur selon l'invention peuvent éventuellement être chargés par du graphite et/ou de la fibre de verre ; ils peuvent également etre renforcés par un tissage de bronze.
L'association des deux parties du matériau composite utilisé pour l'élément d'étanchéité du compresseur selon l'invention peut etre réatisée selon les deux méthodes décrites ci-après. Selon une première méthode, l'as-sociation est obtenue par un système de liaison du type collage au moyen d'un adhésif. L'adhésif devra de préférence etre capable d'atteindre une résistance au pelage supérieure ou égale à 3 KN/m à 100C pour un échantil-lon de 10 mm de largeur. Selon une seconde méthode, l'association est obte-nue par un système de liaison du type brasure sous vide au moyen par exemple d'un alliage or-qermanium ou encore d'argent. L'association peut etre favo-risée, selon la méthode utilisée par une géométrie particulière du matériaucomposite consistant à insérer le polymère ou le composé fritté graphite--argent dans un anneau en alliage métallique.
Le compresseur selon l'invention fonctionne de manière satisfai-sante, c'est-à-dire sans perturbations, pendant une duree supérieure ou égale à 1 000 heures :
- lorsque le fluide à comprimer, liquide ou gazeux, est `a tout étage dudit compresseur à une température comprise entre -30 et +200C, - lorsque la pression de refoulement dudit fluide est supérieure ou égale à
150 bars, - lorsque le mouvement alternatif du compresseur est tel que la vitesse moyenne relative de glissement d'une partie par rapport à l'autre atteint jusqu'à 5 m/s, selon la pression de refoulement3 - lorsque le fluide à comprimer contient des traces de particules abrasives en quantité telle que le coefficient de frottement puisse atteindre ~,5, - lorsque le fluide à comprimer n'est pas autolubrifiant et qu'on ne peut obtenir le secours d'un lubrifiant externe.
Le compresseur à mouvement alternatif selon l'inven~ion trouve de nombreuses applications dans l'industrie chimique et notamment pour la poly-mérisation de l'éthylène ou la copolymérisation de l'éthylène et des ~ -oléfines sous haute pression. En effet il est connu par le brevet français n 2.021.952 de polymériser l'éthylène sous une pression supérieure `a 500 bars et à une température comprise entre 140 et 300C, en présence d'un syst~me catalytique du type Zie~ler. De nombreux systèmes catalytiques de ce type se révèlent adaptés à la polymérisation de l'éthylène, ainsi qu'à
la copolymérisation de l'éthylène avec des -olé~ines, sous pression et température élevées. Ces systèmes ont en commun la présence d'une part d'au moins un composé halogéné de métal de transition et d'autre part d'au moins un activateur choisi parmi les hydrures et les composés organométalliques des métaux des groupes I à III de la Classification Périodique. Parmi les composés halogénés de métal de transition utilisables, bien qu'ils soient très nombreux, on peut citer les complexes 7t -allylique ou benzylique du chrome, du zirconium et du titane, les trichlorures de vanadium et de titane (ce dernier éventuellement syncristallisé avec le chlorure d'aluminium sous la forme TiC13,1/3 AlC13) éventuellement fixés sur un support comprenant par exemple un halogénure, un monohalogénure ou un hydrohalogénure de maynésium.
Tous ces composés peuvent etre utilisés en présence d'agents complexants tels que alcools lourds, alcoolates métalliques, silicates d'alkyle, aryl ou alkylsiloxanes, éthers ou amines. Parmi les activateurs utilisables on peut citer notamment les trialkylaluminiums, les halogénodialkylaluminiums et les alkylsiloxalanes.
Dans un tel procédé de polymérisation ou copolymérisation, le mélange issu du réacteur est envoyé vers un séparateur fonctionnant SOUS une pression de 50 `a 500 bars, dans lequel le polymère est séparé des monomères n'ayant pas réagi, puis les monomères provenant du séparateur sont comprimés jusqu'à la pression de réaction et renvoyés dans le réacteur. On a constaté
que des quantités non négligeables de bas polymères contenant des résidus catalytiques, en particulier des composés d'aluminium ou d'autres composés réducteurs, sont entraînés dans le flux de monomères non réagis a comprimer.
A l'entrée du compresseur, une fraction de bas polymères pouvant apparaître sous forme de particules de granulométrie comprise entre 1 et 250 microns9 est l'une des causes d'abrasion des éléments d'étanchéité du compresseur, dès que la teneur en résidus catalytiques dans le fluide à recycler et comprimer dépasse 0,5 ppm (partie par million).
Un second objet de la présente invention consiste en un procédé de polymérisation de l'éthylène dans un réacteur sous une pression supérieure à
200 bars et `a une température supérieure `a 170C, en présence d'un système catalytique de type Ziegler, le mélange issu du réacteur étant envoyé vers un séparateur sous pression comprise entre 50 et 500 bars dans lequel le polymère est séparé de l'éthylène n'ayant pas reagi9 l'éthylène issu du séparateur étant comprimé jusqu'à la pression du réacteur et renvoyé dans celui-ci, caractérisé en ce que ladite compression de l'éthylène issu du séparateur est effectuée au moyen d'un compresseur `a mouvement alternatif .
8~
.
selon l'invention tel que décrit précédemment. Un te1 procédé présente, du fait du fonctionnement satisfaisant du compresseur, une fiabilité améliorée.
Le procédé selon 1'invention peut être mis en oeuvre en polymé-risant l'éthylène en présence de 1 `a 50 % en poids d'un hydrocarbure inerte tel que propane ou butane par exemple, et/ou en présence de jusqu'`a 2 % en moles d'hydrogene. Le procédé de l'invention est mis en oeuvre de manière continue et peut etre effectué en utilisant des réacteurs soit autoclaves soit tubulaires ou bien en utilisant un réacteur de chaque type. Lesd;ts réacteurs pourront comporter chacun une ou plusieurs zones réactionnelles.
L'invention est également applicable à la copolymérisation de l'éthylène avec des o~ -oléfines telles que propylene et butène-1 par exemple, ainsi qu'`a la terpolymérisation de l'éthylène avec une o~ -oléfine telle que le propylène et avec une dioléfine non conjuguée. S, ~ 33 The present invention relates to a compressor ~ with movement alternative intended for very high pressures and for its application to a process for the polymerization of ethylene and c ~ -olefins.
The present invention aims to solve technical problems posed by compression, under a higher discharge pressure or equal to 150 bars, of a fluid meeting at least one of the three conditions; -following:
- the fluid contains traces of abrasive particles.
- the fluid is not self-lubricating and it intervenes in a process which does not but no external lubricant.
- the flu; de is not self-lubricating and it intervenes in an acceptable process.
both external lubricants but it is solvent for lubricants pos-sibles.
The fluid concerned with the problem of the present invention can be in a liquid or gaseous state, its temperature can be comprised within a range from -30 ~ to f200C on any stage of the compression machine, and finally it can be of very diverse chemical nature, for example helium, ammonia, ethylene, mixture of ethylene and at least one compound chosen from less ~ -olefins, hydrogen, saturated hydrocarbons such as propane or butane.
The compression of a fluid under a higher discharge pressure greater than or equal to 150 bars is carried out ~ generally in a one or more stages of reciprocating compression, each of which cylinder comprises on the one hand a plunger or a cylinder liner and on the other hand a sealing element which can be either (in the case of a plunger) at least one multi-part static seal, either (in the case of a cylinder liner) at least one mobile movable segment rement with the piston. In the case of fittings, dynamic sealing takes place between the lining (s) and the plunger; in the case of segments, dynamic sealing takes place between the cylinder liner and the segment (s) ~ s ~.
When the fluid intended to be compressed does not respond to any of the three conditions listed above, in particular when said fluid is self-lubricating and / or when it does not contain traces of abrasive particles sives, and / or when the contact surfaces constituting the dynamic seal are lubricated, the compression machine operates Satisfactory for a period of a few thousand hours without disturbing bations, up to 7,000 hours, without the need to choose with particular attention the materials constituting the different parts of said machine. For example when you compress ethylene or a mixture of ethylene and polar comonomers up to a discharge pressure often between 150 and 3000 bars, in the part of a high temperature polymerization process in the presence of free radical scavengers as described in particular in French patents 1,584,529, 2,025,887, 2,099,267 and 2,313,399, it is common to use a reciprocating compressor with the plunger or the cylinder liner are made of treated steel or cast iron or a material of the family of metal carbides such as tungsten and whose sealing elements are made of bronze such as bronze UE 9 P con-holding ~% tin, 0.3 to 1% phosphorus and the rest in copper. This holds the fact that the ethylene stream to be compressed does not contain any traces of abrasive sheets.
However, it has been found that when the fluid to be compressed meets at least one of the three conditions listed above, a reciprocating compressor, the parts of which consist of commonly used materials can no longer function satisfactorily doing, that is to say without interruption, that for a number of hours limited to a few hundred, see P a few tens, this number being functional tion of the lack of lubrication and / or the content of abrasive particles in the fluid. The analysis of the causes of this unsatisfactory functioning has shown, notably by optical and electronic microscopic examination of the sur-faces of the sealing elements, excessively rapid wear thereof inevitably leading to seizure of the sealing elements of the compress-sister. The present invention aims to provide solutions to the pro-bl ~ th technique thus exposed.
A first object of the present invention consists of a compress reciprocating sor intended for very high pressures including on the one hand at least one plunger or a cylinder liner formed of a material chosen from cast irons, steels and tungsten carbides-tene and on the other hand at least one sealing element, characterized in that said sealing element consists of a composite material combining on the one hand at least one metal alloy chosen from bronzes and alloys based on titanium and on the other hand, at least one chosen polymer among polytetrafluoroethylenes, polyimides and polyimide-amides, or a graphite-silver sintered compound.
Among the bronzes used for the sealing element of the com ~
presser according to the invention notably features the UE 9 P bronze described above -above. Among the titanium-based alloys usable for the element .
8 ~
of the compressor according to the invention include in particular the alloys titanium and silver ages such as an alloy comprising 94% by weight of titanium tane and 6% by weight of silver. Polymers usable for the element seal of the compressor according to the invention can optionally be loaded with graphite and / or fiberglass; they can also be reinforced by a bronze weaving.
The combination of the two parts of the composite material used for the sealing element of the compressor according to the invention can be made according to the two methods described below. According to a first method, the as-sociation is obtained by a bonding type bonding system using an adhesive. The adhesive should preferably be able to reach a peel resistance greater than or equal to 3 KN / m at 100C for one sample lon 10 mm wide. According to a second method, the association is obtained naked by a connection system of the vacuum brazing type by means for example of a gold-qermanium alloy or of silver. The association can be favored risée, according to the method used by a particular geometry of the composite material consisting in inserting the polymer or the sintered compound graphite-- silver in a metal alloy ring.
The compressor according to the invention operates satisfactorily.
health, that is to say without disturbances, for a longer period or equal to 1000 hours:
- when the fluid to be compressed, liquid or gaseous, is at any stage of said compressor at a temperature between -30 and + 200C, - when the discharge pressure of said fluid is greater than or equal to 150 bars, - when the reciprocating movement of the compressor is such that the speed relative sliding average of one part compared to the other reached up to 5 m / s, depending on the discharge pressure3 - when the fluid to be compressed contains traces of abrasive particles in a quantity such that the coefficient of friction can reach ~, 5, - when the fluid to be compressed is not self-lubricating and cannot be get help from an external lubricant.
The reciprocating compressor according to the invention ~ ion finds numerous applications in the chemical industry and in particular for poly-merification of ethylene or the copolymerization of ethylene and ~ -olefins under high pressure. Indeed it is known by the patent French No. 2,021,952 to polymerize ethylene under higher pressure at 500 bars and at a temperature between 140 and 300C, in the presence of a catalytic system of the Zie ~ ler type. Many catalytic systems of this type appear to be suitable for the polymerization of ethylene, as well as for the copolymerization of ethylene with -ole ~ ines, under pressure and high temperatures. These systems have in common the presence of a share of at least at least one halogenated transition metal compound and on the other hand at least an activator chosen from hydrides and organometallic compounds of metals from groups I to III of the Periodic Table. From halogenated transition metal compounds which can be used, although they are very numerous, mention may be made of the 7t -allylique or benzyl complexes of chromium, zirconium and titanium, vanadium and titanium trichlorides (the latter possibly syncrystallized with aluminum chloride under the form TiC13,1 / 3 AlC13) optionally fixed on a support comprising by for example a halide, a monohalide or a hydrohalide of maynesium.
All these compounds can be used in the presence of complexing agents such as heavy alcohols, metal alcoholates, alkyl silicates, aryl or alkylsiloxanes, ethers or amines. Among the activators that can be used, mention in particular trialkylaluminiums, halogénodialkylaluminiums and alkylsiloxalanes.
In such a polymerization or copolymerization process, the mixture from the reactor is sent to a separator operating UNDER a pressure from 50 to 500 bars, in which the polymer is separated from the monomers unreacted, then the monomers from the separator are compressed up to the reaction pressure and returned to the reactor. We observed that significant quantities of low polymers containing residues catalytic, in particular aluminum or other compounds reducing agents, are entrained in the flow of unreacted monomers to be compressed.
At the inlet of the compressor, a fraction of low polymers which may appear in the form of particles with a particle size between 1 and 250 microns9 is one of the causes of abrasion of the compressor sealing elements, as soon as the content of catalytic residues in the fluid to be recycled and compress exceeds 0.5 ppm (parts per million).
A second object of the present invention consists of a method of polymerization of ethylene in a reactor under a pressure higher than 200 bars and at a temperature above 170C, in the presence of a system Ziegler type catalytic, the mixture from the reactor being sent to a pressure separator between 50 and 500 bars in which the polymer is separated from ethylene that has not reacted with ethylene from separator being compressed to reactor pressure and returned to the latter, characterized in that said compression of the ethylene from separator is carried out by means of a reciprocating compressor .
8 ~
.
according to the invention as described above. Such a process presents, made of the satisfactory operation of the compressor, improved reliability.
The process according to the invention can be carried out in polymer risking ethylene in the presence of 1 to 50% by weight of an inert hydrocarbon such as propane or butane for example, and / or in the presence of up to 2% by moles of hydrogen. The method of the invention is implemented so continuous and can be carried out using reactors or autoclaves either tubular or using a reactor of each type. Lesd; ts reactors may each include one or more reaction zones.
The invention is also applicable to the copolymerization of ethylene with o ~ -olefins such as propylene and butene-1 for example, as well than to terpolymerization of ethylene with an o ~ -olefin such as propylene and with an unconjugated diolefin.
Claims (10)
graphite-argent du matériau composite sont associés par un système de liaison choisi parmi le collage au moyen d'un adhésif et la brassure sous vide. 4. Reciprocating compressor according to claim 1, characterized in that the alloy metallic and the polymer or sintered compound graphite-silver composite material are associated by a bonding system chosen from bonding to using adhesive and vacuum brewing.
150 bars, caractérisée en ce que ladite compression s'effectue dans un compresseur selon la revendication 1, que l'on fait en sorte que la température dudit fluide soit comprise entre -30° et +200°C à tout étage dudit compresseur, et que l'on introduit dans ledit fluide des traces de particules abrasives. 6. Method of compressing a fluid under a discharge pressure greater than or equal to 150 bars, characterized in that said compression takes place in a compressor according to claim 1, which is made so that the temperature of said fluid is between -30 ° and + 200 ° C on any stage of said compressor, and which is introduced into said fluid traces of abrasive particles.
dans celui-ci, caractérisée en ce que l'éthylène issu du séparateur contient au moins 0,5 ppm de résidus dudit système catalytique. 10. Method according to claim 9, applied to an ethylene polymerization process in a reactor under a pressure higher than 200 bars and at a temperature above 170 ° C, pre-sence of a Ziegler type catalytic system, the mixture from the reactor being sent to a pressure separator between 50 and 500 bars in which the polymer is separated from ethylene unreacted, the ethylene from the separator being compressed to reactor pressure and returned therein, characterized in that the ethylene from separator contains at least 0.5 ppm residue of said catalytic system.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR83/07.259 | 1983-05-02 | ||
| FR8307259A FR2545545B1 (en) | 1983-05-02 | 1983-05-02 | ALTERNATE MOTION COMPRESSOR FOR VERY HIGH PRESSURES AND ITS APPLICATION TO A PROCESS FOR THE POLYMERIZATION OF ETHYLENE AND A-OLEFINS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1249983A true CA1249983A (en) | 1989-02-14 |
Family
ID=9288469
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000453277A Expired CA1249983A (en) | 1983-05-02 | 1984-05-01 | HIGH PRESSURE RECIPROCATING MOTION COMPRESSOR AND USE THEREOF FOR THE POLYMERIZATION OF ETHYLENE AND .alpha.-OLEFINS |
Country Status (12)
| Country | Link |
|---|---|
| JP (1) | JPS59207909A (en) |
| AU (1) | AU579789B2 (en) |
| BE (1) | BE899551A (en) |
| CA (1) | CA1249983A (en) |
| CH (1) | CH657896A5 (en) |
| DE (1) | DE3416100C2 (en) |
| ES (1) | ES8707556A1 (en) |
| FR (1) | FR2545545B1 (en) |
| GB (1) | GB2141491B (en) |
| IT (1) | IT1179464B (en) |
| LU (1) | LU85337A1 (en) |
| NL (1) | NL194048C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0333961A1 (en) * | 1988-03-25 | 1989-09-27 | Abg Semca S.A. | Seal ring for a piston |
| FR2611020B1 (en) * | 1987-02-13 | 1990-01-26 | Abg Semca | PISTON SEALING SEGMENT |
| US5316321A (en) * | 1991-07-15 | 1994-05-31 | Teikoku Piston Ring Co., Ltd. | Nonferrous piston ring with hard surface treatment layer |
| WO1998031936A1 (en) * | 1997-01-17 | 1998-07-23 | Maschinenfabrik Sulzer-Burckhardt Ag | Reciprocating compressor |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2852097A (en) * | 1953-04-27 | 1958-09-16 | Union Carbide Corp | Lubricating device |
| DE1027023B (en) * | 1953-05-23 | 1958-03-27 | Dipl Landw Kurt Karsten | Pistons, especially for engines driven by compressed air |
| US3315881A (en) * | 1965-07-23 | 1967-04-25 | Worthington Corp | Self-lubricating system particularly adaptable for use in high pressure compressors |
| DE1806964A1 (en) * | 1968-11-05 | 1970-07-02 | Bbc Brown Boveri & Cie | (semi) hermetically sealed electromotor compressor - for compressing dry or wet gases |
-
1983
- 1983-05-02 FR FR8307259A patent/FR2545545B1/en not_active Expired
-
1984
- 1984-04-19 JP JP59079325A patent/JPS59207909A/en active Granted
- 1984-04-24 CH CH2006/84A patent/CH657896A5/en not_active IP Right Cessation
- 1984-04-25 LU LU85337A patent/LU85337A1/en unknown
- 1984-04-27 IT IT48097/84A patent/IT1179464B/en active
- 1984-04-30 BE BE0/212854A patent/BE899551A/en not_active IP Right Cessation
- 1984-04-30 DE DE3416100A patent/DE3416100C2/en not_active Expired - Lifetime
- 1984-05-01 AU AU27566/84A patent/AU579789B2/en not_active Expired
- 1984-05-01 CA CA000453277A patent/CA1249983A/en not_active Expired
- 1984-05-01 GB GB08411092A patent/GB2141491B/en not_active Expired
- 1984-05-02 NL NL8401387A patent/NL194048C/en not_active IP Right Cessation
-
1986
- 1986-07-28 ES ES556977A patent/ES8707556A1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| GB2141491B (en) | 1987-01-28 |
| NL194048C (en) | 2001-05-03 |
| ES556977A0 (en) | 1987-08-16 |
| DE3416100C2 (en) | 1995-05-18 |
| FR2545545B1 (en) | 1987-04-03 |
| AU579789B2 (en) | 1988-12-08 |
| AU2756684A (en) | 1984-11-08 |
| GB8411092D0 (en) | 1984-06-06 |
| ES8707556A1 (en) | 1987-08-16 |
| NL8401387A (en) | 1984-12-03 |
| IT1179464B (en) | 1987-09-16 |
| CH657896A5 (en) | 1986-09-30 |
| FR2545545A1 (en) | 1984-11-09 |
| LU85337A1 (en) | 1984-09-24 |
| BE899551A (en) | 1984-10-30 |
| GB2141491A (en) | 1984-12-19 |
| JPS59207909A (en) | 1984-11-26 |
| IT8448097A0 (en) | 1984-04-27 |
| NL194048B (en) | 2001-01-02 |
| DE3416100A1 (en) | 1984-11-15 |
| JPH0460132B2 (en) | 1992-09-25 |
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