Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
  • B01D15/02—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor with moving adsorbents
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D15/00—Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor
  • B01D15/08—Selective adsorption, e.g. chromatography
  • B01D15/10—Selective adsorption, e.g. chromatography characterised by constructional or operational features
  • B01D15/18—Selective adsorption, e.g. chromatography characterised by constructional or operational features relating to flow patterns
  • B01D15/1807—Selective adsorption, e.g. chromatography characterised by constructional or operational features relating to flow patterns using counter-currents, e.g. fluidised beds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2215/00—Separating processes involving the treatment of liquids with adsorbents
  • B01D2215/02—Separating processes involving the treatment of liquids with adsorbents with moving adsorbents
  • B01D2215/021—Physically moving or fluidising the adsorbent beads or particles or slurry, excluding the movement of the entire columns

Definitions

• the present invention relates to a column construction which includes a movable adaptor that can be used to deliver liquid to or to lead liquid away from a liquid permeable bed in which it is desired to adsorb a substance present in the incoming liquid.
• the adaptor may also be used in the desorption/- elution/washing of the bed.
• movable is meant that the adaptor can be moved in the direction of flow applied during an adsorption/desorption/ washing process .
• a fluidized (expanded) bed consists of particles and a through-flowing liquid that keep the particles suspended within a given volume. Such beds have long been used in fermentation processes, among others. In recent times the fluidized bed has also been used as a separation medium in liquid chromatography
• Particles which have a density which is higher than the density of a surrounding liquid can be fluidized by allowing liquid to flow through the bed in a direction which opposes the direction of gravity (an upwardly directed flow) .
• an upwardly directed flow is required to fluidize the bed.
• a fluidized bed is considered to be stable when each individual particle keeps within a given cross-section of the column (perpendicular to the flow direction) .
• the settling tendencies of the particles depends on density and size. In the case of a stabilized fluidized bed, this tendency increases continuously along the flow direction. Those particles which have the most pronounced settling tendency position themselves furthest down in the column. See, for instance, WO-A-9218237.
• Stable fluidized beds shall be vertical (+/-0.5°) with vertical flow direction (+/-0.5 0 ) .
• Movable adapters have earlier been used in chromatography in conjunction with matrices which are packed conventionally in columns. This movability has been achieved by applying a controllable force on the matrix via the adaptor, either through
• the height of the construction is twice that of the height of the column (due to the rod mounted on earlier described movable adapters) . * It is difficult to remove air that is able to collect beneath the adaptor (due to the requirement of stationary seals on the earlier described movable adapters) .
• DE 1,642,812 describes in Figure 4 an embodiment of a movable adaptor that is intended for ion-exchange chromatography on a compact bed.
• the adaptor is positioned on top of the bed and is following movements of the bed.
• Figure la is a side view of one embodiment of an upper adaptor.
• Figure lb is a view from above of one embodiment of an upper adaptor comprised of sections. Each small circle represents one section having a flow opening (the centre hole) .
• Figure 2 illustrates the inventive construction that was most preferred on the date from which convention priority is claimed applied for chromatography on a fluidized bed.
• Figure 3 illustrates schematically an inventive construction applied for chromatography on a fluidized bed in which suspended particles have a density which is higher than the density of the through-flowing liquid. The bed is shown in a non-expanded state prior to chromatography (Fig. 3a) , in an expanded state (Fig. 3b) and in a collapsed non-expanded state after chromatography, in which latter state the bed is ready for washing and/or desorption (Fig. 3c) .
• Figure 4 illustrates schematically an inventive construction applied for chromatography on a fluidized bed in which suspended particles have a density which is lower than the density of the through-flowing liquid.
• the bed is shown in a non-expanded state prior to chromatography (Fig. 4a) , in an expanded state (Fig. 4b) and in a collapsed non-expanded state after chromatography, and ready for washing and/or desorption (Fig. 4c) . Details which have mutually the same function have been identified with the same reference numerals, unless otherwise stated.
• the directions of the liquid flows are shown with the aid of arrows .
• the invention relates to a construction which includes a. a vessel (1) which contains a liquid-permeable bed (2) ; b. a bottom adaptor (3) which (I) is placed in the lower part of the vessel and preferably defines the bottom of the vessel, either totally or partially, and (II) has an opening (4) through which liquid can be delivered/led away to/from the lower part of the vessel (preferably the bottom) , said opening (4) being also directed preferably towards the bed
• an upper adaptor (6) which (I) is placed in the upper part of the vessel and preferably covers the cross-sectional area of said vessel completely or partially and (II) has an opening (7) through which liquid is able run from/to the upper part of the vessel, said opening (7) also preferably being directed towards the bed (2) and provided with a distribution facility (8) for distribution/collection of liquid flow towards/from the upper part of the bed; and d. means (23, 24) for leading liquid flow to the adapters (3, 6) through the opening (4) in the lower or bottom adaptor
• the upper adaptor behaves as a buoyant body when in use.
• This buoyancy function can be achieved when the density of the adaptor is lower than the density of the through-flowing liquid, i.e. a density lower than 1 g/cm 3 in the case of water and water-miscible organic solvents.
• the adaptor is thus comprised completely or partially of material which has a density below 1 g/cm 3 . If the adaptor includes material of higher density, this is compensated for with cells of lower compactness, e.g. air cells. Because the adaptor behaves as a buoyant body, it is able to move in the direction of flow (both with and against the flow) .
• the upper adaptor the buoyant adaptor
• the vessel wall or walls there can be permitted between the periphery of the upper adaptor (the buoyant adaptor) and the vessel wall or walls a gap which in normal cases may be 0.01-10 mm in size.
• This gap provides the advantage of avoiding "jamming", enables air beneath the adaptor to be easily removed, enables the adaptor to be set into motion in order to release agglomerates that have caked beneath the net, enables desired sensors (e.g. particle sensors) to be inserted into the liquid zone, and so on.
• An excessively large gap should be avoided, since such a gap may easily result in pockets of liquid in which material is able to collect in an undesirable manner.
• the size of an appropriate gap will depend on the inner diameter of the column casing, among other things.
• the buoyant adaptor (see Fig. la) used in accordance with the invention has at least one liquid opening (7) on its upper side.
• the underside of the adaptor is usually circular in shape (faces towards the bed/matrix) and includes a distributing facility (8) , which may have the form of one single hole or of a number of holes which are distributed uniformly across the underside of the adaptor and are in liquid communication with the opening (7) .
• the distributing facility, or means may be covered with a woven fine-mesh material (net) (9) , in order to prevent particles from the matrix/the bed clogging the distributing facility.
• the adaptor may be comprised of sections (18) , each having a liquid inlet/liquid outlet opening (7) . The sections need not abut one another.
• the vessel (1) containing the liquid-permeable bed may have any one of a number of different geometrical shapes, although the most common and most practical configuration is a generally straight tube (column) , i.e. does not taper, which is positioned vertically.
• the vessel may be made of glass, plastic, metal or some other inert material.
• the liquid may either flow vertically downwards or vertically upwards with the tolerances for fluidized beds given above.
• the precise flow direction is determined by the design of the distribution facility in each adaptor.
• the distributing direction is as a rule the same as for the openings (7) and (4) , respectively.
• the devices (23 and 24) used to lead the liquid flow to/from the upper and the lower adaptor are comprised of connections for hoses or pipes, suitably made of plastic, glass, metal, etc.
• the devices (23 and 24) are only indicated symbolically in the figures.
• the flow of liquid is generated with the aid of an appropriate pump arrangement connected to one or to both of the adapters by means of said devices (23 and 24) .
• the upper adaptor (6) may be provided with means which will enable a counterpress ⁇ re, preferably a controllable counterpressure, to be applied to the adaptor and therewith counteract the pressure generated by the through-flowing liquid.
• This control is preferably effected pneumatically, by constructing the space (10) above the upper adaptor (6) as a gas chamber (most practically an air chamber) having direct connection to the upper side of the upper adaptor.
• a gas chamber can be created by mounting above the upper adaptor (6) in spaced relationship therewith an end-piece (11) which sealingly closes the upper end of the vessel .
• the opening (7) in the upper adaptor (6) is connected to an outer storage vessel or reservoir (not shown) , preferably through the medium of the end-piece (11) , by means of a liquid delivery line (12) , preferably in the form of a flexible hose or a. flexible pipe of the periscope kind.
• the gas chamber (10) includes an inlet (13) which coacts with a valve (14) , preferably an adjustable valve for the outlet/inlet of gas (air) .
• the inlet (13) will normally be arranged on the end-piece (11) .
• the chamber (10) may be connected controllably to a pressure source, preferably via the inlet (13) .
• the column is provided with a graduated vertical level pipe (15) which extends parallel with the vessel (the column) and the function of which may be combined with the function of a gel-bed sensor or some other sensor (16) relevant to the purpose and fixedly mounted on the adaptor.
• the sensor may, in turn, be connected to a signal processing unit (17) .
• the adaptor can be caused to move with the intention of releasing or dislodging any material that has agglomerated on the adaptor, by pulsating the liquid flow through the column or by pulsating the air pressure in the chamber (10) .
• Figures 3 and 4 illustrate an inventive construction applied to a fluidized bed, particularly a stable fluidized bed, in which the particles have either a higher or a lower density than the density of the through-flowing liquid.
• the vessel (1) has the form of an upstanding column.
• the construction includes an air chamber (10) which applies pressure on the upper side of the upper adaptor
• the fluidized bed (primarily a stable bed) can be generated in a zone of the liquid located between the upper and the lower adaptor.
• the inlet is effected via the lower adaptor (3) and the outlet is effected via the upper adaptor (6) , the buoyant adaptor.
• the reference numeral (20) identifies the bed in a non-expanded state, while reference numeral (21) identifies the bed in an expanded state.
• the reference numeral (20) identifies the bed in a non-expanded state, whereas the reference numeral (21) shows the bed in an expanded state.
• the bed is expanded and adsorption takes place, there will preferably be found a particle-free liquid layer (19) between the lower surface of the expanded bed and the bottom adaptor (3) .
• the described structures may be mounted on a stand provided with feet which can be adjusted to facilitate vertical positioning of the structure.
• the stand may have the form of at least three stable pull rods which are placed uniformly around and parallel with the walls of the vessel (the column) .
• the bottom parts of the rods are bent radially outwards from the vessel (the column) , in order to improve stability.
• the vessel (1) (the column) is filled with liquid to a predetermined level in a first process stage.
• the vessel is filled with liquid which flows in through either the bottom or the upper adaptor.
• the direction of the incoming liquid flow is determined by whether the particles have a higher or lower density than the density of the incoming liquid (see above) .
• the liquid outlet should be closed when filling the vessel, and the valve to the gas chamber open.
• the flow is allowed to continue with the outlet open and the gas chamber closed, optionally after adjusting the rate of flow, until expansion of the fluidized bed is complete, for instance when a stable fluidized bed has been reached.
• undesired material can be washed away by passing an appropriate buffer through the bed with the bed fully expanded, partially expanded or in a non-expanded state.
• the extent to which the bed is expanded can be changed by adjusting the pressure and/or changing the flow rate.
• Desorption is effected with a desorption buffer, suitably with the bed in a non-expanded state and with the buffer flowing in a direction opposite to the direction in which adsorption took place. Prior to desorption, the bed is allowed to return to its non-expanded state, whereafter the flow is reversed and adjusted so that a thin particle-free liquid layer will form between the outlet adaptor (which is normally used as the inlet adaptor for the desorption process) and the non- expanded bed. Washing and desorption may be effected in accordance with Figures 3c and 4c.

Landscapes

• Chemical & Material Sciences (AREA)
• Analytical Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
• Treatment Of Liquids With Adsorbents In General (AREA)
• Vibration Dampers (AREA)
• Peptides Or Proteins (AREA)
• External Artificial Organs (AREA)
• Orthopedics, Nursing, And Contraception (AREA)
• Apparatus Associated With Microorganisms And Enzymes (AREA)

Priority Applications (6)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20392718

Family Applications (1)

Country Status (8)

Cited By (4)

Families Citing this family (5)

Citations (5)

Family Cites Families (5)

• 1994
  • 1994-01-28 SE SE9400263A patent/SE9400263L/sv not_active Application Discontinuation
• 1995
  • 1995-01-20 US US08/676,167 patent/US5759395A/en not_active Expired - Fee Related
  • 1995-01-20 WO PCT/SE1995/000051 patent/WO1995020427A1/en active IP Right Grant
  • 1995-01-20 AT AT95908401T patent/ATE172127T1/de not_active IP Right Cessation
  • 1995-01-20 EP EP95908401A patent/EP0741600B1/en not_active Expired - Lifetime
  • 1995-01-20 JP JP52000595A patent/JP3689109B2/ja not_active Expired - Fee Related
  • 1995-01-20 AU AU16734/95A patent/AU677896B2/en not_active Ceased
  • 1995-01-20 DE DE69505350T patent/DE69505350T2/de not_active Expired - Fee Related

Patent Citations (5)

Also Published As

Similar Documents

Legal Events