Patent Publication Number: US-2003230004-A1

Title: Batch fluid bed processor

Description:
RELATED APPLICATIONS  
     [0001] Benefit of U.S. Provisional Application Serial No. 60/389,482 filed on Jun. 17, 2002 is hereby claimed, which application is incorporated herein by reference. 
    
    
     
       BACKGROUND OF THE INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The present invention relates to a fluid bed processor and, more particularly to a fluid bed processor for small batches.  
       [0004] 2. Brief Description of Related Developments  
       [0005] Fluid bed processors are known in the granulating art. For example, Glatt Air Techniques, Inc. of Ramsey, N.J., USA markets and sells a GPCG multi purpose fluid bed processing tool. The GPCG tool has interchangeable processing chambers for applications such as top spray processing or Wurster processing. The GPCG tool is designed to handle batches in the kilogram range. When undertaking R&amp;D for pharmaceutical applications, smaller batches than the kilogram range are required. In order to process smaller batches, for example, in the less than 100 gram range, a smaller tool is required than a tool such as the GPCG tool. Smaller tools require additional capital investment and may not offer the full capabilities as the GPCG tool, such as being explosion proof for applications requiring flammable solvents such as alcohol or ethanol. Accordingly, there is a desire to provide a batch fluid bed processor capable of processing a wider range of batches for use in both production and R&amp;D pharmaceutical applications.  
       SUMMARY OF THE INVENTION  
       [0006] In accordance with one embodiment of the present invention, a batch fluid bed processing machine is provided for processing products. The batch fluid bed processing machine has a container and a gas source coupled to a first end of the container. An expansion chamber is provided and coupled to a second end of the container. An expansion funnel is provided having a second open end coupled to an interface between the expansion chamber and the container. A column is mounted in the container between the expansion funnel and the gas source. A gas stream is passed from the gas source and through the container. Products may be coated or dryed in the gas stream.  
       [0007] In accordance with another embodiment of the present invention, a batch fluid bed processing machine is provided for processing batches of products. The batch fluid bed processing machine has a container and a gas source coupled to the container and adapted to pass a gas stream through the container. An expansion chamber is provided and coupled to the container. An expansion funnel is located at least partially in the container. The expansion funnel has an open upper end and an open lower end, the open upper end being located downstream the open lower end. A larger quantity of products may be dried or coated where the expansion funnel is removed from the container.  
       [0008] In accordance with another embodiment of the present invention, a method of batch fluid bed processing is provided comprising the steps of providing a product container and coupling an expansion chamber to the product container. Steps of then coating, granulating or drying a first quantity of product in the container are then provided. Steps of then removing the first quantity of product from the container and coupling an expansion funnel to the container are then provided. Steps of then coating, granulating or drying a second quantity of product in the container, where the second quantity is less than the first quantity are then provided. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0009] The foregoing aspects and other features of the present invention are explained in the following description, taken in connection with the accompanying drawings, wherein:  
     [0010]FIG. 1 is a side schematic section view of a fluid bed processor;  
     [0011]FIG. 2 is a side schematic section view of a batch fluid bed processor;  
     [0012]FIG. 3 is a top view of a distribution plate;  
     [0013]FIG. 4 is a side schematic section view of a batch fluid bed processor; and  
     [0014]FIG. 5 is a top view of a distribution plate. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0015] Referring to FIG. 1, there is shown a side section view of a batch fluid bed processor  2  within the teachings of the present invention. Although the present invention will be described with reference to the embodiments shown in the drawings, it should be understood that the present invention can be embodied in many alternate forms of embodiments. In addition, any suitable size, shape or type of elements or materials could be used.  
     [0016] A batch fluid bed processor  2  of the type shown may be adapted to coat, mix and granulate products or substances such as powders and/or liquids. Such powders and/or liquids may be powder components, granulating solutions, bulking agents or active ingredients in the form of powder, liquids or atomized liquids. Alternately, a batch fluid bed processor  2  of the type shown may be adapted to mix and/or granulate other types of products or substances. The batch fluid bed processor  2  may be a Wurster system type or coater that includes a product container section  4 , an expansion chamber  6  into which the upper end of the product container section  4  opens at an interface between the container section  4  and expansion chamber  6 , and a lower plenum  8  disposed beneath the product container. The upper end of the expansion chamber  6  may open into a filter housing (not shown) including the necessary filter structure and outlet. A distribution plate and/or screen  10  is disposed between the container section  4  and the lower plenum  8 . A Wurster coater type system is described in U.S. Pat. No. 5,437,889 that is hereby incorporated by reference in its entirety. The distribution plate or screen  10  has a plurality of passage openings  12  through which air or gas from the lower plenum  8  may pass into the product container section  4 . In alternate embodiments, a screen  11  may also be provided upstream of air distribution plate  10 . The holes in the plate  10  in the area outside the cylindrical column  14  may be smaller in diameter than the holes beneath the partition or column  14 . This results in higher air volumes and velocities in the central area or upbed  26  of container  4  than in the down bed area  24  of container  4 . The product container  4  has a cylindrical column  14  supported by spiders  16 ,  18 . Although column  14  is shown with a cylindrical shape, other suitable shapes may be provided in alternate embodiments. Column  14  may be vertically adjustable within container  4  to modify the recirculating behavior of products or particles  64  in container  4  to be coated or dried. The partition or column  14  has open upper and lower ends,  20  and  22 . The lower end  22  is spaced above the distribution plate or screen  10 . The column or partition  14  divides the interior of the product container section  4  into an outer annular downbed area  24  and interior upbed  26 . In alternate embodiments, column or partition  14  may not be provided. A spray nozzle assembly  28  is mounted at or through the distribution plate  10  and projects upwardly into the interior of the cylindrical partition or column  14  and the upbed  26 . The spray nozzle  28  receives a supply of gas under pressure through a gas supply line  30  and coating liquid line under pressure through a liquid supply line  32 . The spray nozzle assembly  28  discharges a spray pattern  34  of gas and coating liquid. For coating applications, spray nozzle  28  is active. For drying applications, spray nozzle  28  is inactive. Air or gas is introduced into lower plenum  8  from blower or fan assembly  36 . Fan assembly  36  draws air or gas into the plenum  8  from an upstream gas source  60 . Fan Assembly  36  may be fixed speed or a variable speed type to allow control of gas flow or pressure through plenum  8 . Air or gas may be filtered and/or heated by passing through heat exchanger  38  and/or filter  40 . Heat exchanger  38  may be fixed in the amount of heat to be transferred to the air or gas or in alternate embodiments may be variable to allow more or less heat to be transferred to the air or gas. Air or gas introduced into the lower plenum  8  passes upwardly through the openings  12  formed through the air distribution plate or screen  10 . Products or substances  64  such as powders and/or liquids that are to be coated, mixed, granulated or dryed are placed in product container  4  while air or gas is circulated through container  4 . Particles passing upwardly that enter into the spray pattern  34  are coated when spray pattern  34  is active.  
     [0017] To reduce the amount of product or substances to be processed in a given batch, an expansion funnel  42  is inserted and located downstream column or partition  14 . Expansion funnel  42  has an open upper end  44  and an open lower end  46  with the open upper end  44  being located downstream the open lower end  46 . In the embodiment shown, expansion funnel  42  is conical in shape. In alternate embodiments, any suitable shape may be provided. The open upper end  44  of expansion funnel  42  has a flange  48  captured at the interface between the flange  52  of the upper end of the product container section  4  and the flange  56  of the lower end of expansion chamber  6 . Seal  64  and/or seal  66  may be provided to seal flange  52  to flange  56  and/or flange  48  of expansion funnel  42 . By inserting expansion funnel  42  into the batch fluid bed processor  2 , the effective area of the base of expansion chamber  6  is reduced from the cross section area of the opening in flange  56  to the cross section area of lower end  46  of expansion funnel  42 . As a result, smaller quantities of product may be processed in the batch fluid bed processor  2  with the combination expansion chamber  6  and expansion funnel  42  than with the expansion funnel  42  not present. With the use of expansion funnel  42 , a tool that is designed to handle larger batches, such as in the kilogram range, may be easily modified in order to process smaller batches, for example, in the less than 100 gram range without having to supply a smaller tool that requires additional capital investment and may not offer the full capabilities of the larger tool. As a result, a batch fluid bed processor can be made capable of processing a wider range of batches allowing the same tool for use in both production and R&amp;D pharmaceutical applications.  
     [0018] Referring now to FIG. 2, there is shown a side section view of the batch fluid bed processor  2  within the teachings of the present invention having an alternate embodiment kit to reduce the batch processors capacity. Referring also to FIG. 3, there is shown a top view of distribution plate  70 . The batch fluid bed processor  2  includes a product container section  4 , an expansion chamber  6  into which the upper end of the product container section  4  opens at an interface between the container section  4  and expansion chamber  6 , and a lower plenum  8  disposed beneath the product container. A distribution plate and/or screen  70  is disposed between the container section  4  and the lower plenum  8 . The distribution plate or screen  70  has a plurality of passage openings  72  through which air or gas from the lower plenum  8  may pass into the product container section  4 . In alternate embodiments, a screen  76  may also be provided upstream of air distribution plate  70 . Plate  70  does not have holes in the area  78  outside the cylindrical column  80 . Plate  70  has holes  72  within the area  82  beneath cylindrical column  80 . Holes  72  further away from pilot  84  may be smaller in diameter than the holes  72  closer to pilot  84 . This results in higher air volumes and velocities in the central area of column  80 . In alternate embodiments, any suitable shape and number of holes  72  may be provided. Although column  80  is shown with a cylindrical shape, other suitable shapes may be provided in alternate embodiments. Column  80  has open upper and lower ends,  86  and  88 , the lower end  88  being seated on distribution plate  70 . A secondary distribution plate and/or screen  110  is disposed between a shoulder  114  of column  80  and a shoulder  116  of nozzle  28 . The distribution plate or screen  110  has a plurality of passage openings  118  through which air or gas from the lower plenum  8  may pass into the product container section  4 . In alternate embodiments, a screen  119  may also be provided upstream of secondary distribution plate  110 . Holes  118  further away from the center of secondary plate  110  may be smaller in diameter than the holes closer to the center. This results in higher air volumes and velocities in the central area of column  80 . In alternate embodiments, any suitable shape and number of holes  118  may be provided. A spray nozzle assembly  28  is mounted at or through the distribution plate  70  and projects upwardly into the interior of the cylindrical column  80 . The spray nozzle  28  receives a supply of gas under pressure through a gas supply line  30  and coating liquid line under pressure through a liquid supply line  32 . The spray nozzle assembly  28  discharges a spray pattern  90  of gas and coating liquid. Air or gas is introduced into lower plenum  8  from blower or fan assembly  36 . Air or gas may be filtered and/or heated by passing through heat exchanger  38  and/or filter  40 . Air or gas introduced into the lower plenum  8  passes upwardly through the openings  72  formed through the air distribution plate or screen  70 . Products or substances  92  such as powders and/or liquids that are to be coated, mixed, granulated or dryed are placed in product container  4  while air or gas is circulated through container  4  in and above column  80 . Particles passing upwardly that enter into the spray pattern  90  are coated when spray pattern is active. An expansion funnel  94  is inserted and located downstream column  80 . Expansion funnel  94  has an open upper end  96  and an open lower end  98  with the open upper end  96  being located downstream the open lower end  98 . Products or substances  92  are isolated from the volume outside of column  80  by a combination of expansion funnel  94 , column  80  and secondary distribution plate  70 . In the embodiment shown, expansion funnel  94  is conical in shape. In alternate embodiments, any suitable shape may be provided. The open lower end  98  of expansion funnel  94  is seated on the open upper end  86  of column  80 . A seal  99  may be provided to seal the open lower end  98  of expansion funnel  94  with the open upper end  86  of column  80 . The open upper end  96  of expansion funnel  94  has a flange  100  captured at the interface between the flange  52  of the upper end of the product container section  4  and the flange  56  of the lower end of expansion chamber  6 . Seal  64  and/or seal  66  may be provided to seal flange  52  to flange  56  and/or flange  100  of expansion funnel  94 . By inserting expansion funnel  94  into the batch fluid bed processor  2 , the effective area of the base of expansion chamber  6  is reduced from the cross section area of the opening in flange  56  to the cross section area of lower end  98  of expansion funnel  94 . As a result, smaller quantities of product may be processed in the batch fluid bed processor  2  with the combination expansion chamber  6  and expansion funnel  94  and column  80  than with the expansion funnel  94  and column  80  not present. With the use of expansion funnel  94  and column  80 , a tool that is designed to handle larger batches, such as in the kilogram range, may be easily modified in order to process smaller batches, for example, in the less than 100 gram range without having to supply a smaller tool that requires additional capital investment and may not offer the full capabilities of the larger tool. As a result, a batch fluid bed processor can be made capable of processing a wider range of batches allowing the same tool for use in both production and R&amp;D pharmaceutical applications.  
     [0019] Referring now to FIG. 4, there is shown a side section view of the batch fluid bed processor  2  within the teachings of the present invention having an alternate embodiment kit to reduce the batch processors capacity. Referring also to FIG. 5, there is shown a top view of distribution plate  120 . The batch fluid bed processor  2  includes a product container section  4 , an expansion chamber  6  into which the upper end of the product container section  4  opens at an interface between the container section  4  and expansion chamber  6 , and a lower plenum  8  disposed beneath the product container. A distribution plate and/or screen  120  is disposed between the container section  4  and the lower plenum  8 . The distribution plate or screen  120  has a plurality of passage openings  122  through which air or gas from the lower plenum  8  may pass into the product container section  4 . In alternate embodiments, a screen  124  may also be provided upstream of air distribution plate  120 . Plate  120  has holes both in the area  126  outside the cylindrical column  80  and within the area  128  beneath cylindrical column  80 . Holes  122  further away from pilot  130  may be smaller in diameter than the holes  122  closer to pilot  130 . This results in higher air volumes and velocities in the central area of column  80 . In alternate embodiments, any suitable shape and number of holes  122  may be provided. Column  80  has open upper and lower ends,  86  and  88 , the lower end  88  being seated on distribution plate  120 . A secondary distribution plate and/or screen  110  is disposed between a shoulder  114  of column  80  and a shoulder  116  of nozzle  28 . In alternate embodiments, a screen  119  may also be provided upstream of secondary distribution plate  110 . A spray nozzle assembly  28  is mounted at or through the distribution plate  120  and projects upwardly into the interior of the cylindrical column  80 . The spray nozzle assembly  28  discharges a spray pattern  136  of gas and coating liquid. Air or gas is introduced into lower plenum  8  from blower or fan assembly  36 . Air or gas may be filtered and/or heated by passing through heat exchanger  38  and/or filter  40 . Air or gas introduced into the lower plenum  8  passes upwardly through the openings  122  formed through the air distribution plate or screen  120 . Products or substances  140  such as powders and/or liquids that are to be coated, mixed, granulated or dryed are placed in product container  4  while air or gas is circulated through container  4  in and above column  80  and surrounding column  80 . Particles passing upwardly that enter into the spray pattern  136  are coated when spray pattern is active. An expansion funnel  144  is inserted and located downstream column  80 . Expansion funnel  144  has a plurality of passage openings  146  through which air or gas from the lower plenum  8  may pass through the product container section  4  and through expansion funnel  144 . In alternate embodiments, a screen  148  may also be provided upstream or downstream of expansion funnel  144 . In alternate embodiments, expansion funnel  144  may be made from a screen material instead of a perforated material. Holes  146  may have smaller holes further away the centerline in diameter than the holes closer to the centerline This results in higher air volumes and velocities in the central area of column  80 . In alternate embodiments, any suitable shape and number of holes  146  may be provided. Products or substances  140  are isolated from the volume outside of column  80  by a combination of expansion funnel  144 , column  80  and secondary distribution plate  110 . Air or gas, in this embodiment, may pass through container  4  on both sides of column  80  and through expansion funnel  144 . Expansion funnel  144  has an open upper end  152  and an open lower end  154  with the open upper end  152  being located downstream the open lower end  154 . In the embodiment shown, expansion funnel  144  is conical in shape. In alternate embodiments, any suitable shape may be provided. The open lower end  154  of expansion funnel  144  is seated on the open upper end  86  of column  80 . A seal  99  may be provided to seal the open lower end  154  of expansion funnel  144  with the open upper end  86  of column  80 . The open upper end  152  of expansion funnel  144  has a flange  158  captured at the interface between the flange  52  of the upper end of the product container section  4  and the flange  56  of the lower end of expansion chamber  6 . Seal  64  and/or seal  66  may be provided to seal flange  52  to flange  56  and/or flange  158  of expansion funnel  144 . By inserting the combination of expansion funnel  144 , plate  120  and column  80  into the batch fluid bed processor  2 , a larger volume of gas or air may be transferred while still having the amount of product  140  to be processed reduced while maintaining product processing parameters such as heat and air or gas flow consistent with processing requirements. As a result, smaller quantities of product may be processed in the batch fluid bed processor  2  with the combination present than with the combination not present. Accordingly, a tool that is designed to handle larger batches, such as in the kilogram range, may be easily modified in order to process smaller batches, for example, in the less than 100 gram range without having to supply a smaller tool that requires additional capital investment and may not offer the full capabilities of the larger tool. As a result, a batch fluid bed processor can be made capable of processing a wider range of batches allowing the same tool for use in both production and R&amp;D pharmaceutical applications.  
     [0020] It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Such alternatives or modifications could be combining different expansion funnels with different columns or no columns as an example. Such alternatives or modifications could be mounting the expansion funnel further within the expansion chamber or product container as a further example. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.