US3661330A - Apparatus for drying polyester particles - Google Patents

Apparatus for drying polyester particles Download PDF

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Publication number
US3661330A
US3661330A US10679*A US3661330DA US3661330A US 3661330 A US3661330 A US 3661330A US 3661330D A US3661330D A US 3661330DA US 3661330 A US3661330 A US 3661330A
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particles
cylindrical body
zone
drying
lower portion
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Expired - Lifetime
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US10679*A
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English (en)
Inventor
Seibi Yamada
Yoshiharu Asada
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Teijin Ltd
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Teijin Ltd
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/12—Powdering or granulating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B13/00—Conditioning or physical treatment of the material to be shaped
    • B29B13/06—Conditioning or physical treatment of the material to be shaped by drying
    • B29B13/065—Conditioning or physical treatment of the material to be shaped by drying of powder or pellets
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/78—Preparation processes
    • C08G63/785—Preparation processes characterised by the apparatus used
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/88—Post-polymerisation treatment
    • C08G63/90—Purification; Drying
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
    • C08J2367/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds

Definitions

  • This invention relates to an improved process for drying polyester particles, and to the apparatus suited for the practice thereof. More particularly, the invention relates to a process of pre-heating non-crystalline polyester particles to cause crystallization thereof and thereafter heating and drying the crystallized particles, the characteristic features residing in that the process comprises the first step of heating and crystallizing non-crystalline particles of polyester which are packed in such a manner that they are movable downwards by their own weight, at temperatures ranging 120200 C., preferably l50l90 C., with mechanical agitation of preferably mild conditions, until at least the surfaces of the particles are substantially crystallized, and the immediately succeeding step of heating and drying the particles maintained under the above packed state but without the agitation.
  • the invention furthermore concerns with the apparatus for practicing the above process.
  • polyester presents more problems for ideal drying, compared with other polymers.
  • polyester containing any substantial amount of water When polyester containing any substantial amount of water is melted, its ester linkages are hydrolyzed to reduce its degree of polymerization. This lowering in the degree of polymerization is more or less an inherently inevitable phenomenon with polyester, which noticeably deteriorates the quality of the articles shaped from the polyester.
  • a jacketed drying cylinder was designed.
  • the jacket was divided into plural zones, and heated air current was separately supplied to each zone, so that the upper zone was given a temperature suited for crystallization of polyester pellets, and the lower zone, a temperature suited for drying.
  • a temperature gradient was formed inside the cylinder, and whereupon polyester pellets were supplied from the upper part of the cylinder to be withdrawn from the bottorn thereof, the cylinder being so designed that the content thereof could continuously move downward by the selfweight, at a harmonious rate with the withdrawal.
  • the repetitive experiments using the above cylinder however proved that the aforesaid deficiencies in the batch system were essentially inavoidable, since the polyester pellets in approximately the lower half of the cylinder were invariably perfectly fused and adhered.
  • the object of the invention is to provide a drying process of polyester particles which present more problems to be solved in the drying step compared with other polymers, the process being free of the aforementioned numbers of drawback; and to provide apparatuses suited for practicing the said process.
  • polyester particles is used to cover polymer particles of any of normally employed configurations, such as granule, flake, pellet, and the like.
  • polyester of the invention includes the typical polyesters such as those prepared from dibasic acids and dihydric alcohols, e.g., polyethylene terephthalate, and polyesters prepared from terephthalic acid and 1,4-cyclohexanedimethanol; as well as those containing, as the third component, optional dibasic acid or dihydric alcohol such as isophthalic acid, adipic acid, trimethylene glycol bis-phenol A, etc. as being copolymerized.
  • polyesters containing poly-functional compounds such as pentacrythritol, the term poly-functional referring to at least tri-functional, and polyesters containing carbonate linkages such as polycarbonate, are within the scope of polyester used in the invention. In other words, the term is to cover all the polyesters which possess ester linkages, exhibit more or less the fusing phenomenon during the drying step, and which can be crystallized by heating.
  • the object of the subject process can be accomplished by the two-stage drying process which comprises the first step of heating and crystallizing non-crystalline polyester particles which are packed in such a manner that they are movable downwards by their own weight, at temperatures ranging l200 C., preferably 150l90 C., with mechanical agitation of preferably mild conditions as will not substantially deform the configuration of particles, until at least the surfaces of the particles are substantially crystallized, and the immediately succeeding step of heating and drying the particles, maintaining the packed state of the particles which are downwardly movable by their own weight, but without the mechanical agitation.
  • the highest feasible crystallization temperature is employed. While the specific temperature varies depending on the type of polyester and shape of the particles, normally temperatures ranging l20200 C., preferably 150-l90 C., are employed. At the temperatures below the lower limit, the crystallization of polyester particles is insufficient, and the occurrence of fusing phenomenon in the subsequent drying step under no agitation cannot be avoided. Also at a temperature above 200 C., more or less the decomposition of polyester is inavoidable.
  • the crystallization is performed until at least the surfaces of tHe polyester particles are substantially crystallized.
  • This surface crystallization is easily discernible without special equipment, since upon the crystallization the particle surfaces become opaque, which is appreciable with naked eye.
  • lt is very important in this process that the polyester particles are maintained within the zone under the mechanical agitation until such opaqueness appears on the surfaces thereof, while they are packed in such a manner that they are movable downwards by their own weight, and that thereafter the particles are heated and dried while kept under the so packed state but without the mechanical agitation.
  • the packed system as a whole gradually moves downwards by the self-weight, as the dried matter is withdrawn from a lower part of the apparatus.
  • the stirring action should not affect the particles being heated and dried, since such fails to achieve the objects of the invention.
  • the mechanical agitation is stopped before the opaqueness observable with naked eye appears on the particle surfaces, neither the objects of the invention can be accomplished.
  • the heating is suitably performed by passing hot gaseous current through the crystallization and drying zones. ln that case it is preferred to introduce the gaseous current separately into the two zones, inter alia, to introduce one current into the crystallization zone at the spot close to the feed entrance of the polyester particles, and another, into the drying zone at the spot close to the exit of the dried matter, discharging the exhaust currents from a spot between the two.
  • air is the most conventional heating gas
  • inert gases such as nitrogen, argon, carbon dioxide, etc., their mixtures, or mixtures of air with the inert gases, can be utilized if so desired.
  • the agitation in the crystallization zone is performed, preferably in such a manner as will avoid the exertion of positive pushing-down action on the polyester particles, in addition to the gradual downward movement thereof in the packed state which is caused by their own weight.
  • an agitation device as will push down the particles, such as the screw-type device with blades, should preferably be avoided.
  • stirring as will somewhat suppress the downward movement of the particles by their own weight, .e., such mechanical agitation as will not entirely inhibit the downward motion of the particles but exert thereon a slight lifting motion to a direction opposite from the downward movement, is permissible.
  • the downward movement of the particles by their own weight taking place with the withdrawal of the dried matter from a lower part of the apparatus, can be controlled to a certain degree by such lifting action of the agitation.
  • a compact apparatus suited for practicing the subject process can be directly mounted on the upper portion of the polyester pellet feeder of an extruder of spinning machine, for example, so as to completely avoid the disadvantageous phenomena which tend to occur during the transfer ofthe dried pellets to the extruder.
  • the apparatus for drying polyester particles which is suitable for practicing the subject process, comprises a column in which non-crystalline particles of polyester are packed in such a manner that they are movable downwards by their selfweight, a feed entrance of the particles provided at an upper part of the column, crystallization zone in the upper area of the column in which the particles are heated until at least the surfaces thereof are substantially crystallized, an inlet for introducing a hot gaseous current into said zone, a stirrer for agitating the particles in said zone, a drying zone provided below and in succession to the crystallization zone, an inlet for introducing a hot gaseous current into the drying zone from a lower portion of the zone, an exit for the dried polyester particles provided at the bottom of the column, and at least one exhaust for the heating gaseous currents provided on the said column.
  • FIG. l is a diagrammatic vertical section showing one embodiment of such an apparatus.
  • FIGS. 2 and 4 show other embodiments of the apparatus in the similar manner
  • FIGS. 3 and 4 show a modification of the apparatus of FIG. 2.
  • FIG. 3' is a horizontal section cut along the line A-A of FIG. 3.
  • FIG. l an example of forming the column from cylinder 7 with feed entrance 1 for the particles, cylinder 2 composing the crystallization zone, cylinder 8 of a greater diameter than that of the cylinder 2, provided below -and in succession to the cylinder 2 to serve as the drying zone, and an adapter 7 which serves as the bottom of the column, is shown.
  • a mechanical stirrer 3 is equipped, which is rotated by motor 4 (shown by a side view, not as section).
  • the rotation shaft is rotatably fixed on the upper part of the cylinder 7
  • a gas inlet 6 is provided on the upper portion of the cylinder 2
  • the column needs not be composed of such four members, but may be made of one to three members.
  • the cylinder 8 should have a diameter greater than that of the cylinder 2.
  • the length of cylinder 8 is suitably at least approximately five times its inner diameter, normally approximately 5 to 6 times.
  • the heated gaseous currents separately passing through the crystallization zone and drying zone are combined and discharged from a common exhaust 5, but if desired, they may be supplied from 9 and 5, respectively, and together withdrawn from 6. Or, an additional exhaust of the heating gaseous current may be provided at a lower portion of the crystallization zone.
  • FIG. 2 shows a modification of the embodiment of FIG. l, in which the cylinder 2 is contained in the upper part of the cylinder 8.
  • the stirrer of the construction suited to give mild stirring action which is preferred for the subject process is employed.
  • the spiral blade which somewhat resembles an extended spring, to a suitable direction, a slight lifting motion can be exerted on the polyester particles present in the zone. If the stirrer is rotated to the counter-direction of the above, the same will push down the particles, which should be in all cases avoided.
  • the stirrer is preferably installed at a position at which the lower end of the stirrer substantially corresponds with the lower end of the cylinder 2. Also when the inner diameter of cylinder 2 is expressed by D2 and the rotation diameter of the stirring blade, by D2, in the suitable designing the ratio D,/D2 becomes no more than 3.5, normally 3.0-2.0, in order to prevent the occurrence of tackiness, undesirable pulverization and/or deformation of the pellets which may be caused by the stirring.
  • the appropriate rotation rate differs depending on shape and arrangement of the blades, but for the specific type shown in FIG. 2, it is no more than l0 r.p.m., normally l02 r.p.m.
  • the cylinder 2 may be supported on the cylinder 8 by any suitable means, for example, by a flange 2' as shown in FIG. 2. Or, a suitable projection may be provided on the cylinder 8, and cylinder 2 may be mounted thereon with any suitable device such as a flange or arm. Conversely, suitable projection may be provided on the cylinder 2 and the cylinder 8, provided with a flange or arm, so that the former can be mounted on the latter. If desired, the two cylinders may be permanently fixed, but preferably the two are detachably fitted. l
  • non-crystalline polyester particles are fed from entrance l, an the dried particles are continuously withdrawn from the exit l0. In the meantime the particles move downwards by their own weight, maintaining the movably packed state.
  • the non-crystalline polyester particles in the cylinder 2 are crystallized by the heated gaseous current fed from the inlet 6 and flowing through the spaces l2 and 13 downwards in the cylinder 2, while being stirred, under the mildest feasible agitation condition, by the stirrer 3, and move into the drying zone below.
  • a heated gaseous current is fed from the inlet 9 and rises through the same zone.
  • the gaseous current flowing down through the cylinder 2 and that flowing up through the drying zone are combined, and discharged from the exhaust 5 as shown by the arrow in the drawing.
  • the adapter 7 is preferably installed in such a manner as will form an annular space 1l at the lower end portion of cylinder 8 as illustrated in FIG. 2, the space 11 contributing to uniformize the supply of gaseous current for drying into cylinder 8, and consequently to effect uniform heating the inlet 9 for the hot gaseous current is opened to the annular space with advantage.
  • FIG. 4 shows another embodiment of the apparatus which is similar to that of FIG. 2, except that the stirrer is of the type similar to that shown in FIG. l.
  • the circulation path of the heated gaseous current outside the apparatus is also illustrated.
  • FIG. 4 a modification at the lower end portion of cylinder 2 is indicated with broken lines.
  • the lower end portion of cylinder 2 is enlarged or spread out downwards.
  • the design like the spreading portion 18 smoothes the downward transfer of the packed polyester particles by their own weight, and serves to prevent uneven staying or clogging of the particles in cylinder 2.
  • the lower end portion of cylinder 2 may be left intact as illustrated in FIG. 2, but the portions corresponding to the spreading portion 18 of FIG. 3 may be bored with nu merous perforations to allow passage of air therethrough, Whereby the gaseous current flowing downwards through the cylinder 2 and that flowing upwards through cylinder 8 can together flow into the annular space ll" from the perforations as well as from the gap between the cylinders 2 and 8.
  • the configuration of the perforations isv not critical, which may be slit-type small holes.
  • the term is used in the sense inclusive of any shape of through-holes allowing passage of gases. It is of course possible to design the ap paratus to have both the spreading portion I8 as shown in FIG. 4 and the numerous perforations.
  • a suitable portion of the column below the level of particles feed entrance but above the crystallization zone is cooled.
  • the numeral 24 denotes a pipe for supplying a cooling medium, such as cold water, brine, etc., into jacket 23.
  • the exterior of the heated zone of the column i.e., crystallization zone and/or the drying zone, may be covered with a jacket, so that the column can be additionally heated through the outer walls.
  • the gaseous current discharged through the exhaust can be passed through a cyclone 22 and blower 19, and heated by the heater 20 to be recycled to the inlet 6 into the crystallization zone and inlet 9 into the drying zone.
  • FIGS. 3 and 3 show still another embodiment of the apparatus of the invention, to which a further additional means is provided.
  • the embodiment is generally similar to that of FIG. 2, except that a crumbling means of blocks is provided at the upper portion of the drying zone, in the manner of traversing the same zone.
  • a crumbling means of blocks is provided at the upper portion of the drying zone, in the manner of traversing the same zone.
  • a plural number of rotatory rolls 14 14 are rotatably fitted on the same plane, each piercing through the cylinder 8.
  • Each roll 14 has plural projections thereon disposed along its length, each projection being shifted from the adjacent projection by 90 as illustrated in FIGS. 3 and 3'. Also between any two adjacent rolls, any two corresponding projections are shifted by 90 from each other. All of those rolls are rotatable at a same rate.
  • each of the outermost rotatory rolls 14 facing the inner wall of cylinder 8 is rotated to such direction as will push down the particles a through the space between the inner wall of cylinder 8 and the same roll.
  • this crumbling means is provided directly below the cylinder 2, for easier breaking of the blocks a.
  • 16 16 are the bosses fixed on the wall of cylinder 8 to support the rotatory rolls 14.
  • 14, l5 are gears, and 13 is a chain wheel.
  • the direction of rotation of each roll is indicated with an arrow in FIG. 3'.
  • the directional arrangement as indicated is preferred, because such does no interfere with the downward motion of the particles by their own weight, but rather assists the movement with uniform staying time of individual particles.
  • EXAMPLE Particles of polyethylene terephthalate having an intrinsic viscosity of 0.98 as measured in the orthochlorophenol solution as 25 C. were subjected to a continuous drying by employing the apparatus shown in FIG. 2. Thereafter, the dried particles were directly fed to an ordinary spinning apparatus provided with an extruder and undrawn filaments were thus prepared.
  • the drying was performed by employing the conventional rotatory drum drier, the dried particles were fed to the spinning apparatus through a transfer pipe and a particle-maintaining hopper provided in the upper portion of the spinning apparatus, and thereafter the spinning was performed under the same conditions as above.
  • the results of this run are as follows:
  • the column comprises a first cylindrical body provided with a feed entrance for the particles, a second cylindrical body of larger diameter than the first which forms the first zone, a third cylindrical body of larger diameter than the second which forms the drying zone, and an adapter of larger diameter than the third cylindrical body which forms the bottom portion of the column and contains an outlet for removing dried particles.
  • annular spaces are provided between the lower portion of the second cylindrical body and the upper portion of the third cylindrical body and between the lower portion of the third cylindrical body and the upper portion of the adapter.
  • means for crumbling small blocks is provided at the upper portion of the drying zone, said crumbling means comprising a plurality of rotary rolls which are rotatably disposed in the same plane, traversing the cylindrical body which serves as the heating and drying zone, each roll having a plurality of projections arranged along it length in such a manner that each projection is shifted from the preceding projection by between any two adjacent rolls, any two corresponding projections being shifted from each other by 90, and the two outermost rotary rolls facing the wall of the cylindrical body being so rotated as to push the polyester particles down through the respective space between the roll and the inner wall of the cylindrical body.

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
  • Drying Of Solid Materials (AREA)
  • Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
US10679*A 1967-08-23 1970-01-22 Apparatus for drying polyester particles Expired - Lifetime US3661330A (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2427349A1 (fr) * 1978-05-29 1979-12-28 Montedison Spa Procede de preparation d'un polycarbonate granulaire
US4231991A (en) * 1976-09-18 1980-11-04 Buehler-Miag Gmbh Apparatus for crystallizing an amorphous particulate material
EP0092843A3 (en) * 1982-04-28 1984-03-28 Sumitomo Chemical Company, Limited Process for producing an aromatic polyester fiber
EP0755956A3 (en) * 1995-07-25 1997-10-01 Shimadzu Corp Process for the preparation of polylactic acid and apparatus for applying the process
WO2000056510A1 (en) * 1999-03-24 2000-09-28 Sipa S.P.A. Method and apparatus for the treatment of materials in the production of hollow bodies of polyethylene terephtalate
US6461575B1 (en) * 1999-05-11 2002-10-08 Shell Oil Company Apparatus for crystallization of polytrimethylene terephthalate
US6573314B1 (en) * 1998-12-11 2003-06-03 Borealis Technology Oy Method of producing pelletized polyolefin
US6894109B1 (en) 1998-12-11 2005-05-17 Borealis Technology Oy Method of producing pelletized polyolefin
US6972342B1 (en) * 1997-04-10 2005-12-06 Invista North America S.A R.L. Method for producing crystalline carboxylic acids
US20140097278A1 (en) * 2012-06-13 2014-04-10 Recycled Asphalt Shingle Technology Horizontal mixer

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5696099U (enrdf_load_stackoverflow) * 1979-12-25 1981-07-30
JP2010105254A (ja) * 2008-10-29 2010-05-13 Shisuko:Kk 乾燥用ホッパー

Citations (13)

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Publication number Priority date Publication date Assignee Title
US1497084A (en) * 1920-10-06 1924-06-10 Bigot Alexandre Drying kiln
US1880925A (en) * 1927-08-25 1932-10-04 Ig Farbenindustrie Ag Production of coarse crystals
US2069192A (en) * 1936-01-29 1937-01-26 Yorktown Electric Roaster Mfg Automatic roaster
US2474833A (en) * 1946-02-27 1949-07-05 Eric W Eweson Method for making organic fertilizer
US2475984A (en) * 1944-03-11 1949-07-12 Standard Oil Dev Co Process for drying hydrogel catalysts
US2480146A (en) * 1944-02-02 1949-08-30 Lee Foundation For Nutritional Method and apparatus for dehydration
US2883709A (en) * 1954-01-29 1959-04-28 Continental Gin Co Cotton drier and feed control
DE1142843B (de) * 1959-08-25 1963-01-31 Metallgesellschaft Ag Verfahren zur Herstellung eines poroesen Agglomerates
FR1438583A (fr) * 1965-04-05 1966-05-13 Dessiccateur de poudre
US3251291A (en) * 1962-08-24 1966-05-17 Blaw Knox Co Agglomerating apparatus for powdered food solids or the like
US3325912A (en) * 1964-06-05 1967-06-20 Bojner Gustav Apparatus for treatment of loose materials with gaseous mediums
US3411215A (en) * 1966-12-08 1968-11-19 Du Pont Apparatus and process for drying particulate polymer
US3423840A (en) * 1965-10-21 1969-01-28 Dorr Oliver Inc Cone tray heat exchanger

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1497084A (en) * 1920-10-06 1924-06-10 Bigot Alexandre Drying kiln
US1880925A (en) * 1927-08-25 1932-10-04 Ig Farbenindustrie Ag Production of coarse crystals
US2069192A (en) * 1936-01-29 1937-01-26 Yorktown Electric Roaster Mfg Automatic roaster
US2480146A (en) * 1944-02-02 1949-08-30 Lee Foundation For Nutritional Method and apparatus for dehydration
US2475984A (en) * 1944-03-11 1949-07-12 Standard Oil Dev Co Process for drying hydrogel catalysts
US2474833A (en) * 1946-02-27 1949-07-05 Eric W Eweson Method for making organic fertilizer
US2883709A (en) * 1954-01-29 1959-04-28 Continental Gin Co Cotton drier and feed control
DE1142843B (de) * 1959-08-25 1963-01-31 Metallgesellschaft Ag Verfahren zur Herstellung eines poroesen Agglomerates
US3251291A (en) * 1962-08-24 1966-05-17 Blaw Knox Co Agglomerating apparatus for powdered food solids or the like
US3325912A (en) * 1964-06-05 1967-06-20 Bojner Gustav Apparatus for treatment of loose materials with gaseous mediums
FR1438583A (fr) * 1965-04-05 1966-05-13 Dessiccateur de poudre
US3423840A (en) * 1965-10-21 1969-01-28 Dorr Oliver Inc Cone tray heat exchanger
US3411215A (en) * 1966-12-08 1968-11-19 Du Pont Apparatus and process for drying particulate polymer

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4231991A (en) * 1976-09-18 1980-11-04 Buehler-Miag Gmbh Apparatus for crystallizing an amorphous particulate material
FR2427349A1 (fr) * 1978-05-29 1979-12-28 Montedison Spa Procede de preparation d'un polycarbonate granulaire
EP0092843A3 (en) * 1982-04-28 1984-03-28 Sumitomo Chemical Company, Limited Process for producing an aromatic polyester fiber
EP0755956A3 (en) * 1995-07-25 1997-10-01 Shimadzu Corp Process for the preparation of polylactic acid and apparatus for applying the process
US5880254A (en) * 1995-07-25 1999-03-09 Shimadzu Corporation Method for producing polylactic acid and apparatus used therefor
US6972342B1 (en) * 1997-04-10 2005-12-06 Invista North America S.A R.L. Method for producing crystalline carboxylic acids
US20050228118A1 (en) * 1998-12-11 2005-10-13 Karin Knudsen Method of producing pelletized polyolefin
US6573314B1 (en) * 1998-12-11 2003-06-03 Borealis Technology Oy Method of producing pelletized polyolefin
US6894109B1 (en) 1998-12-11 2005-05-17 Borealis Technology Oy Method of producing pelletized polyolefin
WO2000056510A1 (en) * 1999-03-24 2000-09-28 Sipa S.P.A. Method and apparatus for the treatment of materials in the production of hollow bodies of polyethylene terephtalate
US6461575B1 (en) * 1999-05-11 2002-10-08 Shell Oil Company Apparatus for crystallization of polytrimethylene terephthalate
US20140097278A1 (en) * 2012-06-13 2014-04-10 Recycled Asphalt Shingle Technology Horizontal mixer
US9295992B2 (en) * 2012-06-13 2016-03-29 Recycled Asphalt Shingle Technology, Llc Horizontal mixer

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JPS5125377B1 (enrdf_load_stackoverflow) 1976-07-30

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