Abstract:
A chromatography column having a longitudinal axis and comprising a column wall with a first end and a second end, a first end plate assembly removably connectable to said first end of the column wall, a second end plate assembly removably connectable to said second end of the column wall, wherein said first end plate assembly, said column wall and said second end plate assembly are arranged along the longitudinal axis of the column wherein the column wall, and/or first end plate assembly and/or second end plate assembly is/are rotatable about an axis of rotation wherein said axis of rotation is parallel to the longitudinal axis of said column and positioned outside the column.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to chromatography columns of the type mentioned in the preambles of the independent claims.  
       BACKGROUND OF INVENTION  
       [0002]     Chromatography columns may be used in industrial process to purify process liquids and separate substances of interested from process liquids. Prior art chromatography columns comprise a column wall in the form of hollow column tube which is connected to a removable upper end plate assembly and a removable lower end plate assembly. One end plate assembly is provided with a process fluid inlet arrangement, typically comprising an inlet pipe and an inlet valve and the other end plate assembly is provided with a process fluid outlet arrangement, typically comprising an outlet pipe and an outlet valve. Each end of the column tube is usually provided in the interior of the column with a removable distribution system. These inlet and outlet distribution systems may be attached to the respective end plate assembly or the upper distribution system may be arranged to be movable towards or away from the end plate assembly. During use, the space in the column between the distribution systems is usually filled with a chromatography medium. If necessary a retaining mesh may be provided between each distribution system and the media. The inlet distribution system is intended to distribute incoming fluid evenly over the surface of the media at the inlet end of the column while the outlet distribution system is intended to collect fluid evenly from the surface of the media at the outlet end of the column. Such a column may weigh several tonnes. Typically the end plate assemblies are bolted to flanges provided at each end of the column. Alternatively the end plate assemblies may be connected by longitudinal tie bars. Seals are usually provided between the end plates assemblies, inlet and outlet pipes, distribution systems and valves in order to prevent leakage. Columns are typically provided with legs to raise the lower end plate assembly off the ground in order to provide access to the lower end plate assembly, the inlet or outlet pipe and the valve arrangement. When such a column requires maintenance to, or cleaning of, internal components, such as the valves, seals, distribution systems, etc. lifting gear such as a crane is necessary to lift the upper end plate assembly off the column tube and the column tube off the lower end plate assembly.  
       SUMMARY OF THE INVENTION  
       [0003]     According to the present invention, at least some of the problems with the prior art are solved by means of a device having the features present in the characterising part of claim  1 . 
     
    
     BRIEF DESCRIPTION OF THE FIGURES  
       [0004]      FIG. 1   a  shows a partial cross-sectional view of a first embodiment of a chromatography column in accordance with the present invention.  
         [0005]      FIG. 1   b  shows a plane view from above of the column of  FIG. 1   a.    
         [0006]      FIG. 2  shows a view corresponding to that of  FIG. 1   a  wherein the first end plate and distribution system have been raised above the column wall.  
         [0007]      FIG. 3  shows a view corresponding to that of  FIG. 2   a  wherein the first end plate and distribution system have been raised above the column wall, and the column wall has been raised above the second end plate.  
         [0008]      FIG. 4  shows a view corresponding to that of  FIG. 3  wherein the first end plate and distribution system have been raised above the column wall, and the column wall has been raised above the second end plate and rotated out from a position between the first and second end plates.  
         [0009]      FIG. 5  shows the column after the feed system has be relowered in order to allow easy access to it.  
         [0010]      FIG. 6  shows a perspective view of a second embodiment of the present invention having only 2 extendable legs.  
         [0011]      FIG. 7  shows a side view of the column of  FIG. 6  with the cylinder wall in a position corresponding to that of  FIG. 4 .  
         [0012]      FIGS. 8-14  shows lateral views and cross-sections of a third embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0013]      FIGS. 1-5  show a first embodiment of a chromatography column  1  in accordance with the present invention. Column  1  comprises a hollow column wall  3 , which in this embodiment is in the form of a cylinder  5 , with a first open end  7  and a second open end  9 . Each open end  7 ,  9  is provided with an outward projecting circumferential flange  11 , respectively  13 , arranged perpendicular to the longitudinal axis L of the column wall  3 . A first end plate assembly  15  is removably fastened to flange  11  and a second end plate assembly  17  is removably fastened to flange  13 . In this embodiment of the present invention the column is intended to be used in the down-flow mode, i.e. the first end plate assembly  15  is intended to be used to feed fluids to the column  1  and the second end plate assembly is intended to be used to remove fluids from the column, however the present invention is equally applicable to columns using the up-flow mode. In use, column wall  3  may be occupied by a chromatography medium  19 . First end plate assembly  15  is provided with the usual fluid feed system  21  (also called “movable adapter”) comprising one or more valves, distribution channels, distribution nets, nozzles, connectors, etc which are well-known in the art and which are referenced collectively under the reference number  21 . In this example of a column, first end plate assembly  15  comprises first end plate  23  which is removably fastenable to flange  11 , and which has a central opening  25  through which a hollow shaft  27  is movable in the longitudinal direction of the column by a motor  29 . In use, hollow shaft  27  projects into the column cavity  31  and supports the fluid feed system. Motor and drive assembly  29  can be used to move the movable adapter  21  towards and away from first end plate  23  and thereby adjust the depth of movable adapter  21  in the column  1 . Second end plate assembly  17  is provided with the usual fluid collecting system  33  comprising one or more valves, distribution channels, distribution nets, nozzles, connectors, etc. which are well-known in the art and which are referenced collectively under the reference number  33 .  
         [0014]     Column  1  is supported in frame  35 . Frame  35  comprises feet  37  in contact with the ground. Feet  37  support three extendable legs  39 ,  41 ,  43  which extend upwards and are each provided with a substantially horizontal arm  45 ,  47 ,  49 . Arms  45 - 49  pass over the column  1  are attached to end plate  23 . Extendable legs  39 - 41  are provided with lifting means such as jacks or rams arranged to be able to lift arms  45 - 49  and the first end plate  23  sufficiently high enough so that when movable adapter  21  has been raised to its closest possible position to the underside of first end plate  23  it is possible to raise the first end plate assembly  15  so that none of it is inside the column wall  3 .  
         [0015]     Column wall  3  is attached to leg  41  by a pair of arms  51 ,  53  which are mounted on a sleeve  55  on leg  41 . Sleeve  55  is rotatable around leg  41  and is also movable along the longitudinal axis “ 1 ” of leg  41 .  
         [0016]      FIGS. 1   a  and  1   b  show the chromatography column in the normal operating condition with first and second end plates sealed against the ends of column wall.  FIGS. 2-4  shows stages in rearranging the column allow access to the distribution systems and end plates.  
         [0017]     In  FIG. 2 , the column is shown after it has been emptied of media and fluids, movable adapter  21  has been raised by motor until it is close to the bottom of first end plate assembly and then first end plate has been unfasten from the top of column wall and raised by means of extendable legs  39 - 41  so that the lowest part of movable adapter  21  is above the top of cylinder wall.  
         [0018]     In  FIG. 3 , the column is shown after column wall has been detached from second end plate assembly and sleeve  55  has been raised along the longitudinal axis “ 1 ” of  41  so that none of movable adapter  21  or second end plate assembly is inside the cylinder wall.  
         [0019]      FIG. 4  shows the column after the cylinder wall has been rotated about axis “ 1 ” so that the column wall is no longer positioned between the first and second end plate assemblies.  
         [0020]      FIG. 5  shows the column after the movable adapter has be relowered in order to allow easy access to it.  
         [0021]      FIG. 6  shows a perspective view of a second embodiment of the present invention having only 2 extendable legs.  
         [0022]      FIG. 7  shows a side view of the column of  FIG. 6  with the cylinder wall in a position corresponding to that of  FIG. 4 .  
         [0023]      FIGS. 8-14  show lateral views of a third embodiment of a column in accordance with the present invention. In this embodiment of a column, the column has two-legs  339 ,  341  and is adapted so that the movable adapter lifting means such as motor and drive assembly  329  for the movable adapter  321  is able to be used for extending the legs  339 ,  341 . Thus no jacks or rams are needed to extend the column legs  339 ,  341 . In order to achieve this upper end of the column wall  303  is provided with at least one movable adapter locking pin  371  able to be moved to and from locking engagement with a locking bore  373  arranged on movable adapter  321 . Preferably the locking pin  371  and locking bore  373  are arranged so that locking pin  371  is able to be moved into locking bore  373  when the movable adapter has been raised to substantially its uppermost position. When locking pin(s) is/are in locking engagement with movable adapter  321  relative movement between movable adapter  321  and the column wall  303  is prevented.  
         [0024]     Legs  339  and  341  are each provided with an upper telescopic shaft locking pin  375  able to be moved to and from a position where it prevents movement of telescopic shafts  379  which are slidably arranged in the upper portions of legs  339 ,  341 . Preferably the locking pins  375  are arranged so that locking pins  375  are able to be moved into locking position when the telescopic shafts  379  has been raised to substantially their most extended positions, thereby locking telescopic shafts  379  in the raised position.  
         [0025]     Leg  341 , which supports column wall arms  351 ,  353 , is provided with a locking hole  381  into which a locking pin  383  mounted on arm  353  may be moved into and out of locking engagement. Preferably the locking pin  383  and locking hole  381  are arranged so that locking pin  383  is able to be moved into locking hole  381  when the column wall  303  has been raised to a position where it is no longer in contact with second end plate assembly  317 .  
         [0026]     The following description and  FIGS. 8-14  describe and illustrate the steps of a method in accordance with the present invention for rearranging the components of a column in order to allow the column wall  303  to be rotated to a position where it is no longer between the column legs  339 ,  341 .  
         [0027]      FIG. 8  shows a column  301  in its normal operating position with the movable adapter  321  in a possible working position inside column wall  303  and telescopic shafts  379  retracted.  
         [0028]      FIG. 9  shows a first step in the method in which the movable adapter lifting means  329  has raised the movable adapter  321  to substantially its uppermost position and movable adapter locking pin  371  has been slid into engagement with locking bore  373  thus preventing further relative movement between movable adapter  321  and column wall  303 .  
         [0029]      FIG. 10  shows the next stage in the method in which the removable fastening means such as bolts  385  for releasably fastening first end plate assembly  315  to the upper end of column wall  303  and bolts  387  for releasably fastening second end plate assembly  317  to the lower end of column wall  303  have been unfastened and removed.  
         [0030]      FIG. 11  shows the next stage in the method in which movable adapter lifting means  329  has been actuated in the way which during normal operation would cause the movable adapter to be moved downwards. However, as movable adapter  329  is locked by locking pin  371  and locking bore  373  to column wall, it is not possible for movable adapter  329  to descend—instead first end plate assembly  315  and all the column components rigidly attached to it such as telescopic shafts  379  and movable adapter lifting means  329  are raised. This movement is continued until telescopic shafts  379  have been extended sufficiently far so as to allow telescopic shaft locking pins  375  to be moved into position which prevent the telescopic shafts  379  being lowered.  
         [0031]      FIG. 12  shows the following stage in the method after movable adapter lifting means  329  has been actuated in the way which during normal operation would cause the movable adapter to be moved upwards. As movable adapter  321  is attached to column wall  303  this has caused column wall to be lifted off second end plate assembly  317 . The movement has been continued until locking pin  383  has become aligned with locking hole  381  at which point locking pin  383  has been slid into locking hole  381 . Column wall  303  is now unable to be lowered as any downward movement is prevented by the interaction of locking pin  383  on arm  353  with leg  341 .  
         [0032]      FIG. 13  shows a subsequent stage in the method in which movable adapter locking pin  371  has been moved out of engagement with locking bore  373  thereby allowing movable adapter to move relative to column wall  303 . Movable adapter lifting means  329  has been actuated to lift movable adapter  321  so that none of it is inside column wall  303 .  
         [0033]      FIG. 14  shows a further stage in the method in which arms  351 ,  353  supporting column wall  303  have been rotated around leg  341 , thereby moving column wall  303  out from between first and second end plate assemblies  315 ,  317 .  
         [0034]     While examples of embodiments of the present invention have been illustrated with columns using movable adapters, it is conceivable to adapt the present invention to columns which do not use movable adapters. In such cases lifting means need to be arranged to lift the first (upper) end plate assembly and column wall from the second (lower) end plate assembly, after which the column wall is prevented from being raised (e.g. by locking its supporting arms to legs in analogy with above), the fastenings between the first end plate assembly and column wall are released and the first endplate assembly raised until it is above the column wall which then may be rotated to the side. Analogously, it is also possible to adapt the present invention to columns which do not have an upper end plate assembly. In such cases the adapter must be provided with releasable locking means which can be used to lock it to the column wall in order to allow it to be used to raise the column wall off the lower end-plate.  
         [0035]     In a further embodiment of the present invention in addition to the cylinder wall being arranged to be able to rotate about axis “ 1 ”, one or more end plates are arranged to be able to rotate about axis “ 1 ”.  
         [0036]     In a further embodiment of the present invention, in addition to, or instead of, being rotatably mounted on a column leg, the arms connecting the column wall to the column leg are made telescopic in the substantially horizontal direction, thereby enabling the column wall to be moved in a straight line out from between the end plate assemblies.  
         [0037]     While the invention has been illustrated by examples in which the vertical movements of column components are achieved using powered means, it is also possible to achieve these movements manually, for example by using brute force or any manner of lifting devices—for example, ropes and pulleys, winches, levers and jacks.  
         [0038]     It is apparent that many modifications and variations of the invention as hereinabove set forth may be made without departing from the spirit and scope thereof. The specific embodiments described are given by way of example only, and the invention is limited only by the terms of the appended claims.