Filter device

Abstract

The present invention relates to a filter device ( 1 ), especially for a fluidised bed system ( 2 ) and particularly for use in pharmaceutical industry, for separating particles being larger than a separating grain from an amount of particles in a fluid flow. The filter device ( 1 ) comprising a housing ( 3 ) and at least one filter portion ( 4 ). A part of said housing ( 3 ) is mounted for rotational movement, and said filter portion ( 4 ) is provided in said housing ( 3 ), whereby the filter portion ( 4 ) is movable upon rotation of said housing ( 3 ). The present invention also relates to a method for separating particles using such a filter device.

1 . A filter device ( 1 ) for a fluidised bed system ( 2 ), particularly for use in pharmaceutical industry, for separating particles being larger than a separating grain from an amount of particles in a fluid flow, said filter device ( 1 ) comprising a housing ( 3 ) and at least one filter portion ( 4 ), characterised in that a part of the housing ( 3 ) is mounted for rotational movement, and that the filter portion ( 4 ) is provided in the housing ( 3 ), whereby the filter portion ( 4 ) is movable upon rotation of the housing ( 3 ).  
     
     
         2 . A filter device according to  claim 1 , characterised in that said part of the housing ( 3 ) is formed like a drum.  
     
     
         3 . A filter device according to  claim 2 , characterised in that said filter portion ( 4 ) is disposed at the circumference of the drum.  
     
     
         4 . A filter device according to any of the claims  1 - 3 , characterised in that said filter portion ( 4 ) comprises several filter members ( 5 ) arranged in such a way that interstices ( 6 ) are formed between the filter members ( 5 ).  
     
     
         5 . A filter device according to  claim 4 , characterised in that said filter portion ( 4 ) is movable upon rotation of the housing ( 3 ) in a direction intersecting at least a plurality of the filter members ( 5 ), whereby the separating grain of the filter device ( 1 ) is determined by the velocity of motion of the filter portion ( 4 ) in the direction of movement during operation of the filter device ( 1 ) and by the size of the interstices ( 6 ) between the filter members ( 5 ).  
     
     
         6 . A filter device according to any of the claims  1 - 5 , characterised in that said filter portion ( 4 ) is provided inside a vessel ( 18 ) that initially contains the fluid and the particles to be separated.  
     
     
         7 . A filter device according to any of claims  1 - 5 , characterised in that said filter portion ( 4 ) is provided in a conduit in connection with the vessel ( 18 ) forming a passage for the fluid and the particles to be separated.  
     
     
         8 . A filter device according to  claim 6 , characterised in that said housing ( 3 ) extends on both sides of the vessel ( 18 ), whereby a first part comprising the filter portion ( 4 ) is mounted inside the vessel ( 18 ) and a second part, mounted outside the vessel ( 18 ) is provided with at least one fluid outlet ( 9 ).  
     
     
         9 . A filter device according to any of the claims  1 - 8  characterised in that said housing ( 3 ) is detachably arranged in a filter holder means ( 8 ).  
     
     
         10 . A filter device according to  claim 9 , characterised in that said housing ( 3 ) is provided with a collar ( 10 ) for detachable connection to the filter holder means ( 8 ).  
     
     
         11 . A filter device according to any of the claims  1 - 10 , characterised in that said housing ( 3 ) comprises first and second body parts ( 11 ,  12 ) which are detachably interconnected.  
     
     
         12 . A filter device according to any of the claims  1 - 11 , characterised in that said housing ( 3 ) is provided with connector means ( 13 ) for connection to a motor unit ( 14 ).  
     
     
         13 . A filter device according to  claim 12 , characterised in that the speed of the motor unit ( 14 ) is variable for variation of the rotational velocity of the filter portion ( 4 ) during operation of the filter device ( 1 ) for obtaining the desired separating grain.  
     
     
         14 . A filter device according to any of the claims  4 - 13 , characterised in that the filter portion ( 4 ) is constituted by a mesh, and the filter members ( 5 ) thus being the threads of the mesh.  
     
     
         15 . A filter device according to any of the claims  4 - 13 , characterised in that the filter portion ( 4 ) is constituted by elongated filter members ( 5 ), which are bars arranged in parallel.  
     
     
         16 . A filter device according to any of the claims  4 - 15 , characterised in that the interstices ( 6 ) between the filter members ( 5 ) is larger than each of the particles ( 7 ) in the fluid flow.  
     
     
         17 . A filter device according to any of the claims  1 - 16 , characterised in that the housing ( 3 ) defines a plurality of equally spaced filter inlet openings ( 15 ), each opening being covered by a filter portion ( 4 ).  
     
     
         18 . A filter device according to any of the claims  1 - 16 , characterised in that the housing ( 3 ) defines a plurality of equally spaced filter outlet openings ( 9 ) for withdrawal of the fluid and particles that have passed the filter portion ( 4 ).  
     
     
         19 . A filter device according to any of the claims  9 - 18 , characterised in that an open space ( 16 ) is defined between the housing ( 3 ) and the filter holder means ( 8 ), to which open space ( 16 ) fluid pressure is provided which constitutes a fluid pressure seal between the housing ( 3 ) and the filter holder means ( 8 ).  
     
     
         20 . A filter device according to  claim 19 , characterised in that the width of open space ( 16 ) is variable by means of adjuster element ( 17 ) provided adjacent to the filter holder means ( 8 ).  
     
     
         21 . Method, for a fluidised bed system ( 2 ) and particularly for use in pharmaceutical industry, for separating particles being larger than a separating grain from an amount of particles in a fluid flow, using a filter device ( 1 ) according to any of the claims  1 - 20 .  
     
     
         22 . Use of a filter device ( 1 ) according to any of the claims  1 - 20 .  
     
     
         23 . Use of a method according to  claim 21.