US2807451A - Columns for contacting liquids with gases or vapours - Google Patents

Columns for contacting liquids with gases or vapours Download PDF

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Publication number
US2807451A
US2807451A US394176A US39417653A US2807451A US 2807451 A US2807451 A US 2807451A US 394176 A US394176 A US 394176A US 39417653 A US39417653 A US 39417653A US 2807451 A US2807451 A US 2807451A
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plate
gases
vapours
ring
columns
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US394176A
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Kuhni-Rietmann Margrit
Fritz H Kuhni
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
    • B01D3/14—Fractional distillation or use of a fractionation or rectification column
    • B01D3/32—Other features of fractionating columns ; Constructional details of fractionating columns not provided for in groups B01D3/16 - B01D3/30
    • B01D3/324—Tray constructions
    • B01D3/328—Sealing between the column and the trays
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
    • B01D3/14—Fractional distillation or use of a fractionation or rectification column
    • B01D3/16—Fractionating columns in which vapour bubbles through liquid
    • B01D3/22—Fractionating columns in which vapour bubbles through liquid with horizontal sieve plates or grids; Construction of sieve plates or grids

Definitions

  • the invention relates to columns of the stated kind in which the plates are formed in known manner so that in operation each of them carries a quantity of liquid up to a restricted depth, into and through which liquid gases or vapours rising from the underlying compartment penetrate through the plate perforations. bviously it is necessary to maintain a pressure gradient over each plate, by which the liquid carried on the plate is supported; and it is therefore necessary to prevent the ascending gases or vapours from llowing around the edge of the plate, for which reason such edge is sealed, Iby an asbestos packing ring or the like, with respect to the wall of the shell.
  • An object of the invention is to simplify and improve the connection or joint between the edges of the plates and the wall of the shell.
  • the edges of the plates are sealed against the wall of the shell by annular elements consisting entirely of metal which encircle the plates and bear elastically against the wall of the shell with a certain degree of pressure, the open expansion slots of these elements being narrower than the individual perorations in the plates.
  • said open expansion slots are arranged below the level of the perforations in the pertaining plate in such manner that a somewhat higher column of liquid extends over them than over the above-mentioned perforations; this measure reliably prevents the pressure difference or gradient necessary for proper operation of the plate from escaping through the expansion slots.
  • Fig. 1 is a partial sectional elevation of a cylindrical column with a sealing ring according to the invention.
  • Fig. 2' is a sectional elevation on a larger scale of the sealing region.
  • Fig. 3 is a plan View of the turnbuckle or tightening means of the sealing ring.
  • Fig. 4 is a perspective view of the ends of the ring foiming the expansion slot.
  • Fig. 5 is a sectional elevation of a modified form of construction of the sealing ring and plate edge.
  • the cylindrical shell 1 the axis of which'is indicated ⁇ by the lines x-y, contains tted plates 2 and 2a provided with a number of capped openings or periorations 3 and 3a for the ascending gases or vapours.
  • the liquid flows on to the plate 2 peripherally through the pipe 4, covers the plate up tothe level indicated by s-b and then flows down through the central overflow pipe 5 on to the plate 2a, whichbecomes covered with the liquid to the level c-d. From the plate 2a, the liquid ilows peripherally through the overow pipe 4a Vto the next subjacent plate (not shown) and so on.
  • the pipes i and 4a are immersed below the levels a-b and c-d; they each, therefore, form a liquid seal through which the gases or vapours ascending from the surface of the liquid, cannot pass. These latter, consequently, flow in the direction of the dotted arrows A through the openings 3 and 3a from below, into the liquid on the plates 2, 2a.
  • rings 6 and 6a The sealing of the plates 2, 2a round their outer edges is performed by rings 6 and 6a, the form of which is more clearly shown in Fig. 2.
  • Each ring is bent-up from a profile bar of inverted F cross-section, the vertical limb 7 of which is pressed rmly against the shell wall 1 while the two horizontal circular limbs 8 and 9 lie respectively below and above the pertaining plate 2 or 2a.
  • a turnbuckle is provided (Fig. 3) between the endsl of each ring 6 or 6a, the two lugs 10 and 11 of which turnbuckle are welded to the two ends of the ring and are pressed apart by two nuts 12, 13 on a screw spindle 14 in such manner that the ring is pressed radially against the shell wall 1.
  • each sealing ring may be a self-tightening sea-ling ring as shown in Fig. 5, consisting of a tightly-wound wire coil spring 15 the ends of which are joined to form a closed ring which is pressed from above into the space between the shell wall 1 and a downward-flanged rim 16 of the pertaining plate 2b.
  • the ring 6 or 6a may be made with only one horizontal limb 8 or 8a if the plate 2 or 2a is by anyA other means prevented from being lifted 01T its support as by pulsations inu the operation of the column; the ⁇ coil spring 15 can itself be replaced by a hanged metal' ring ⁇ made elastic ⁇ by radialV slits and thus ,bearing ⁇ elastic'ally against the shell; it is even possible to ange downthe edge of the plate itself, and slit it radially sothat the elastic, closely spaced tongues thus formed, ⁇ themselves act as sealing means.
  • the plate itself must be made of suitably thin and elastic "sheet metal and its central part then stitfened by ribs or ⁇ the like.
  • said horizontal flange supporting the periphery of said deck
  • said annular member comprising two parallel horizontal flanges, whereby said annular member has a ⁇ cross-section in the shape ofinverted F, the periphery of said ⁇ deck -being inserted into the space between the two horizontal llanges of said annular member.
  • a sealing means interposed between the periphery of the deck and the inner wall of the container, said means comprising an annular member having a vertical and at least one horizontal flange and being coaxially arranged within said cylindrical container, and a turn buckle on said means forcing the vertical llange of saidannular member'radially against the adjacent walls of said container, said horizontal flange supporting the periphery of ⁇ said deck, said ⁇ annular member being radially split, comprising two parallel horizontal llanges and having the form of an open ring having a cross-section of an inverted F, one of the two horizontal flanges of which lits below thedeck and the other flange lits above the deck, and both flanges overlap at the radial split of said ring.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Description

sept. 24, 1957 2,807,451 I l COLUMNS FOR CONTACTING LIQUIDS WITH GASES 0R VAPOURS Filed Nv. 24, l195s.
NagBY fTO/QNEYQ Patented Sept. 24, 1957 CLUlVINS FOR CONTACTING LIQUIDS WITH GASES OR VAPOURS Fritz Kiihni, deceased, late of Allschwil, Switzerland, by Margrit Khni-Rietmann, Allschwil, Switzerland, and Fritz H. Khni, Allschwil, Switzerland, sole heirs Application November 24, 1953, Serial No. 394,176
Claims priority, applicationSwitzerland November Z6, 1952 2 Claims. (Cl. 26,1 114) rthis invention relates to columns for contacting liquids with gases or vapours, comprising a cylindrical shell arranged with vertical axis and divided'into a series of superposed chambers by perforated plates arranged horizontally one above the other in spaced relation. Col umns of this general character are well known for handllng liquids in counterllow to gases or vapours and are employed in the chemical industry, in particular for the washing of gases and for the distillation ot' liquids as etroleum, alkohol and the like.
More especially the invention relates to columns of the stated kind in which the plates are formed in known manner so that in operation each of them carries a quantity of liquid up to a restricted depth, into and through which liquid gases or vapours rising from the underlying compartment penetrate through the plate perforations. bviously it is necessary to maintain a pressure gradient over each plate, by which the liquid carried on the plate is supported; and it is therefore necessary to prevent the ascending gases or vapours from llowing around the edge of the plate, for which reason such edge is sealed, Iby an asbestos packing ring or the like, with respect to the wall of the shell.
An object of the invention is to simplify and improve the connection or joint between the edges of the plates and the wall of the shell.
According to the invention the edges of the plates are sealed against the wall of the shell by annular elements consisting entirely of metal which encircle the plates and bear elastically against the wall of the shell with a certain degree of pressure, the open expansion slots of these elements being narrower than the individual perorations in the plates. Preferably said open expansion slots are arranged below the level of the perforations in the pertaining plate in such manner that a somewhat higher column of liquid extends over them than over the above-mentioned perforations; this measure reliably prevents the pressure difference or gradient necessary for proper operation of the plate from escaping through the expansion slots. It is, of course, not permissible to situate the expansion slots so low that the liquid carried on the plate is able to escape through them; in practice, it is suicient to make such difference in level between about 2% and 10% of the depth of liquid over the plate, usually restricted by an overllow.
By the means of the present invention the use of packing means hitherto necessary for sealing is eliminated and contamination of the column and its contents by crumbling particles of such packing material is avoided; moreover, the removal and replacement of the plates for periodic cleaning of the column is considerably facilitated and cheapened.
The invention will be clearly understood from the following description aided by the accompanying drawings which show two embodiments by way of example.
Fig. 1 is a partial sectional elevation of a cylindrical column with a sealing ring according to the invention.
Fig. 2'is a sectional elevation on a larger scale of the sealing region.
Fig. 3 is a plan View of the turnbuckle or tightening means of the sealing ring. v f
Fig. 4 is a perspective view of the ends of the ring foiming the expansion slot.
Fig. 5 is a sectional elevation of a modified form of construction of the sealing ring and plate edge.
ln accordance with Fig. l, the cylindrical shell 1, the axis of which'is indicated `by the lines x-y, contains tted plates 2 and 2a provided with a number of capped openings or periorations 3 and 3a for the ascending gases or vapours. The liquid flows on to the plate 2 peripherally through the pipe 4, covers the plate up tothe level indicated by s-b and then flows down through the central overflow pipe 5 on to the plate 2a, whichbecomes covered with the liquid to the level c-d. From the plate 2a, the liquid ilows peripherally through the overow pipe 4a Vto the next subjacent plate (not shown) and so on. The pipes i and 4a are immersed below the levels a-b and c-d; they each, therefore, form a liquid seal through which the gases or vapours ascending from the surface of the liquid, cannot pass. These latter, consequently, flow in the direction of the dotted arrows A through the openings 3 and 3a from below, into the liquid on the plates 2, 2a.
The sealing of the plates 2, 2a round their outer edges is performed by rings 6 and 6a, the form of which is more clearly shown in Fig. 2. Each ring is bent-up from a profile bar of inverted F cross-section, the vertical limb 7 of which is pressed rmly against the shell wall 1 while the two horizontal circular limbs 8 and 9 lie respectively below and above the pertaining plate 2 or 2a.
lTo enable the vertical limb '7 to `be pressed rmly against the shell wall, a turnbuckle is provided (Fig. 3) between the endsl of each ring 6 or 6a, the two lugs 10 and 11 of which turnbuckle are welded to the two ends of the ring and are pressed apart by two nuts 12, 13 on a screw spindle 14 in such manner that the ring is pressed radially against the shell wall 1. In order at the same to obtain an as narrow as possible labyrinth expansion slot or passage; the lower horizontal limb 8 on the left-hand end of the sealing ring and the upper horizontal limb 9 on the right-hand -end thereof, project as shown in Fig. 4 a few millimetres beyond the corresponding edge of the vertical limb "l and thus enter into a corresponding recess of the other end. In order to penetrate through the expansion slot of the tightened ring, therefore, the ascending gases or vapo-urs must pass under the plate 2 or 2a into the very narrow horizontal slit remaining between the lower horizontal limb 8 and the plate, which, of course, offers them a far higher ow resistance and is several millimetres lower under the level a-b than the admission openings or perforations 3 o-r 3a. In practice, consequently, the column works in exactly the same manner as a column with tight, asbestos packing rings, or the like.
To remove the plate 2 for example it is only necessary to release the turnbuckle lil- 14, when the plate with its sealing ring 6 can be lifted out of the shell 1. To replace, the plate is lowered from above to the required depth, then exactly adjusted with the turnbuckle fairly loose, and finally fixed in place by tightening the nuts, 12, 13.
in columns of smaller size each sealing ring may be a self-tightening sea-ling ring as shown in Fig. 5, consisting of a tightly-wound wire coil spring 15 the ends of which are joined to form a closed ring which is pressed from above into the space between the shell wall 1 and a downward-flanged rim 16 of the pertaining plate 2b. The very narrow expansion slots below the level of the admission openings of the plate 2b, formed Vbetween the v .y turns or the coil spring 15, olera far higher resistance to the passageof ascending gases or vapours than the admissionopenings 3, so that in this case, also a sui- `cientsealis provided. Itis recommended to t individual plates sealed in this manner, with three feet 17 each, by means `of which they are supported on the underlying -plate. When assembling, the plates can then simply be stacked one on another, each being sealed, when litted "in place, by pushing the coil spring 15 into place. When dismantlingthe plates are preferably withdrawn through 4the bottom of the shell, when the coil springs 15 will of their own accord be released. i
Although only two forms or Aembodiments of the invention `have been described it will now be apparent that these can bey modified, supplemented, or simplified in various details.` For instance, the ring 6 or 6a may be made with only one horizontal limb 8 or 8a if the plate 2 or 2a is by anyA other means prevented from being lifted 01T its support as by pulsations inu the operation of the column; the `coil spring 15 can itself be replaced by a hanged metal' ring `made elastic `by radialV slits and thus ,bearing `elastic'ally against the shell; it is even possible to ange downthe edge of the plate itself, and slit it radially sothat the elastic, closely spaced tongues thus formed, `themselves act as sealing means. In this case, however, the plate itself must be made of suitably thin and elastic "sheet metal and its central part then stitfened by ribs or `the like.
jacent walls of said container, said horizontal flange supporting the periphery of said deck, said annular member comprising two parallel horizontal flanges, whereby said annular member has a `cross-section in the shape ofinverted F, the periphery of said `deck -being inserted into the space between the two horizontal llanges of said annular member.
2, In a bubble deck column, having a cylindrical container arranged with vertical axis and divided into superimposed chambers by at least one horizontally arranged circular bubble deck, a sealing means interposed between the periphery of the deck and the inner wall of the container, said means comprising an annular member having a vertical and at least one horizontal flange and being coaxially arranged within said cylindrical container, and a turn buckle on said means forcing the vertical llange of saidannular member'radially against the adjacent walls of said container, said horizontal flange supporting the periphery of` said deck, said `annular member being radially split, comprising two parallel horizontal llanges and having the form of an open ring having a cross-section of an inverted F, one of the two horizontal flanges of which lits below thedeck and the other flange lits above the deck, and both flanges overlap at the radial split of said ring.
References Cited in the tile of this patent UNITED STATES PATENTS 657,548 Kelsey Sept. 11, 1900 1,320,210 Eckelbarger Oct. 28, 1919 2,011,186 Van Dijck Aug. 13, 1935 2,241,114` Brunjes May 6, 1941 2,619,336 Schilling Nov. 25, 1952 2,645,607 Allen July 14, 1953 FOREIGN PATENTS 140,552 Great Britain Apr. l, 1920 690,798 GreatBritain Apr. 29, 1953 891,411 France Dec. 11, 1943
US394176A 1952-11-26 1953-11-24 Columns for contacting liquids with gases or vapours Expired - Lifetime US2807451A (en)

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BE (2) BE524527A (en)
CH (1) CH319213A (en)
DE (1) DE1025384B (en)
FR (1) FR1094050A (en)
GB (1) GB725130A (en)
NL (1) NL84879C (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2889018A (en) * 1954-07-22 1959-06-02 Standard Oil Co Bubble tray support means
US2939771A (en) * 1958-07-29 1960-06-07 Vulcan Cincinnati Inc Contact apparatus including sealing means
US3125614A (en) * 1959-03-05 1964-03-17 Figure
US3590475A (en) * 1969-06-02 1971-07-06 Air Prod & Chem Method of making contacting column
US3814397A (en) * 1969-06-02 1974-06-04 Air Prod & Chem Contacting column
US20040212106A1 (en) * 2003-04-22 2004-10-28 Koch-Glitsch, Lp Expansion ring for mass transfer column and method employing same
US7267330B1 (en) * 2005-07-06 2007-09-11 Jaeger Products, Inc. Split ring seal
US20230219722A1 (en) * 2020-04-28 2023-07-13 Atkins Nuclear Secured Holdings Corporation Container closure device and method of operating the same

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1066992B (en) * 1956-09-29 1959-10-15 Canzler Fa Carl Exchange tray for rectification columns
BE579015A (en) * 1958-05-31
DE1125406B (en) * 1958-11-22 1962-03-15 Herbert Schroer Threaded bolt and holder bar for fastening intermediate floors in mass transfer columns
DE1085855B (en) * 1959-04-03 1960-07-28 Peter Dinckels & Sohn Column bottom with resilient edge seal
DE1419608B1 (en) * 1960-10-11 1971-07-22 Hoechst Ag Mass transfer column bottom

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US657548A (en) * 1899-08-21 1900-09-11 Sidney E Kelsey Piston-packing.
US1320210A (en) * 1919-10-28 Piston ahd j
GB140552A (en) * 1919-02-07 1920-04-01 Coventry Acme Motor Company Lt Improvements in or relating to the pistons of internal-combustion engines
US2011186A (en) * 1933-02-11 1935-08-13 Willem Johannes Dominicu Dijck Process and apparatus for intimately contacting fluids
US2241114A (en) * 1940-04-25 1941-05-06 Lummus Co Bubble deck construction
FR891411A (en) * 1941-11-12 1944-03-07 Ig Farbenindustrie Ag Device for sealing intermediate floors in distillation and washing columns
US2619336A (en) * 1949-02-02 1952-11-25 Air Prod Inc Gas separation apparatus
GB690798A (en) * 1950-12-29 1953-04-29 Fritz Kuehni Improvements relating to partition plates for gas-liquid contact columns
US2645607A (en) * 1948-10-30 1953-07-14 Us Hoffman Machinery Corp Vaporizer unit and tray

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE309975C (en) * 1918-02-08 1918-12-28
NL72314C (en) * 1941-05-05
DE745661C (en) * 1941-11-12 1944-12-04 Sealing of false floors in distillation and washing columns

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1320210A (en) * 1919-10-28 Piston ahd j
US657548A (en) * 1899-08-21 1900-09-11 Sidney E Kelsey Piston-packing.
GB140552A (en) * 1919-02-07 1920-04-01 Coventry Acme Motor Company Lt Improvements in or relating to the pistons of internal-combustion engines
US2011186A (en) * 1933-02-11 1935-08-13 Willem Johannes Dominicu Dijck Process and apparatus for intimately contacting fluids
US2241114A (en) * 1940-04-25 1941-05-06 Lummus Co Bubble deck construction
FR891411A (en) * 1941-11-12 1944-03-07 Ig Farbenindustrie Ag Device for sealing intermediate floors in distillation and washing columns
US2645607A (en) * 1948-10-30 1953-07-14 Us Hoffman Machinery Corp Vaporizer unit and tray
US2619336A (en) * 1949-02-02 1952-11-25 Air Prod Inc Gas separation apparatus
GB690798A (en) * 1950-12-29 1953-04-29 Fritz Kuehni Improvements relating to partition plates for gas-liquid contact columns

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2889018A (en) * 1954-07-22 1959-06-02 Standard Oil Co Bubble tray support means
US2939771A (en) * 1958-07-29 1960-06-07 Vulcan Cincinnati Inc Contact apparatus including sealing means
US3125614A (en) * 1959-03-05 1964-03-17 Figure
US3590475A (en) * 1969-06-02 1971-07-06 Air Prod & Chem Method of making contacting column
US3814397A (en) * 1969-06-02 1974-06-04 Air Prod & Chem Contacting column
US20040212106A1 (en) * 2003-04-22 2004-10-28 Koch-Glitsch, Lp Expansion ring for mass transfer column and method employing same
WO2004094028A1 (en) * 2003-04-22 2004-11-04 Koch-Glitsch, Lp Expansion ring for mass transfer column and method employing same
US7055810B2 (en) 2003-04-22 2006-06-06 Koch-Glitsch, Lp Expansion ring for mass transfer column and method employing same
JP2006524134A (en) * 2003-04-22 2006-10-26 コーク−グリッシュ，リミティド パートナーシップ Expansion ring
KR101143696B1 (en) * 2003-04-22 2012-05-15 코크-글리취 엘피 Expansion ring for mass transfer column and method employing same
US7267330B1 (en) * 2005-07-06 2007-09-11 Jaeger Products, Inc. Split ring seal
US20230219722A1 (en) * 2020-04-28 2023-07-13 Atkins Nuclear Secured Holdings Corporation Container closure device and method of operating the same

Also Published As

Publication number Publication date
GB725130A (en) 1955-03-02
NL84879C (en)
FR1094050A (en) 1955-05-11
DE1025384B (en) 1958-03-06
BE524528A (en)
CH319213A (en) 1957-02-15
BE524527A (en)

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