Abstract:
Machines and methods adapted to process, for example, to reduce the size of, disperse, or homogenize, a variety of materials and compositions. Such methods and machines are capable of reducing the size of a material and dispersing the material in a liquid by cutting the material with knives located along a perimeter of an annular-shaped cutting head, causing the cut material to flow radially outward from the cutting head through gaps between the knives, and flowing a liquid through passages in the cutting head that cause the liquid to cascade around the knives of the cutting head in an axial direction of the cutting head.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 62/195,940, filed Jul. 23, 2015, the contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention generally relates to methods, machines, and equipment for processing materials, for example, to reduce the size of, disperse, or homogenize a material. 
         [0003]    Various types of equipment are known for processing materials, for example, slicing, dicing, shredding, granulating, comminuting, or otherwise reducing the size of solid materials. A widely used line of comminuting machines is commercially available from Urschel Laboratories, Inc., under the name Comitrol®, aspects of which are disclosed in patent documents including U.S. Pat. Nos. 4,660,778, 4,610,397, 4,657,190, and 5,201,469, whose contents are incorporated herein by reference. Comitrol® machines are capable of uniformly comminuting, dispersing, or homogenizing a wide variety of materials and compositions at high production capacities, for example, food products including fruits, vegetables, dairy products, and meat products, as well as nonfood products including polymeric materials, chemicals, and pharmaceuticals in a variety of forms (e.g., liquids, sols, gels, slurries, pastes, solids, etc.). 
         [0004]    A known configuration for a Comitrol® machine is depicted in exploded views in  FIGS. 1 and 2 . The machine, the particular model of which is the Model 1700, is represented as comprising a cutting assembly  10  and feed hopper  12  through which material is fed to the cutting assembly  10  via a feed tube  13 .  FIGS. 1 and 2  depict the cutting assembly  10  as comprising an impeller  24  rotatably mounted within an annular-shaped cutting head  26 . An electric motor  14  and drive belt  16  rotate a spindle  22  on which the impeller  24  is mounted for rotating the impeller  24  within the cutting head  26 . Material delivered through the feed hopper  12  to the rotating impeller  24  is forced by paddles or blades  25  of the impeller  24  into engagement with uniformly spaced knives  40  mounted at the inner perimeter of the cutting head  26  and oriented parallel to the impeller axis. The spacings between the knives  40  affect the size of the resulting size-reduced product. An upper enclosure  18  surrounds the cutting assembly  10 , from which size-reduced material exits and falls before being discharged from the machine through a lower enclosure  20 . The particular cutting assembly  10  depicted in  FIG. 1  is referred to as a “Microcut,” which is especially well suited for performing dispersion and homogenization processes to produce a variety of liquids, sols, gels, slurries, pastes, etc. As evident from  FIG. 1 , the depicted configuration is adapted to be mounted with a table that supports the motor  12 . 
         [0005]      FIGS. 2, 3 and 4  depict certain components of the machine of  FIG. 1  in more detail.  FIG. 2  depicts the impeller  24  separated from the cutting head  26  and a unit comprising a retaining ring, wear ring and face seal through which the cutting head  26  is mounted within the machine.  FIG. 3  is an exploded view showing certain components of the cutting head  26 , namely, a backing ring assembly  34  that secures a pair of upper and lower knife holding rings  30  and  32  between and to, respectively, a pair of upper and lower support rings  36  and  38  that are spaced apart by posts  39 . The backing ring assembly  34  comprises a pair of upper and lower retainer rings  35 A and  35 B spaced apart by posts  37 , and the retainer rings  35 A and  35 B secure, respectively, the upper and lower knife holding rings  30  and  32  within recesses formed in the upper and lower support rings  36  and  38 .  FIG. 4  is a partial fragmentary view of the cutting head  26  showing the manner in which the knives  40  can be mounted and secured between the knife holding rings  30  and  32  to have a generally radial and axial orientation relative to the head  26  (and, therefore, to the impeller  24 ). Centrifugal force causes material delivered to the high speed rotating impeller  24  to move radially outward into engagement with the knives  40 , where the material strikes exposed cutting edges of the knives  40 . This action results in the removal of small particles from the material until reduction is completed. Particles are discharged through the gaps between the knives  40  before exiting the machine through the upper and lower enclosures  18  and  20 . 
         [0006]    Various other configurations of Comitrol® machines, including their drive systems, knife assemblies and impellers, are also available beyond that represented in  FIG. 1 . As a nonlimiting example, the cutting assembly  10  may comprise an impeller and cutting head that have smaller or larger axial and/or radial dimensions than what is shown in  FIGS. 1 through 4 , for example, including the configurations disclosed in U.S. Pat. Nos. 4,660,778, 4,610,397, 4,657,190. 
         [0007]    Material reduction machines of the type described above and represented in  FIGS. 1 through 4  have performed extremely well for use with a wide variety of materials and applications. For some applications, when dispersing a solid material in a liquid, the solid material and liquid may be delivered to the cutting assembly  10  together via the hopper  12 , for example, combined to form a mixture prior to entering the hopper  12 , or combined within the hopper  12  to form a mixture. In such cases, it may be desirable or necessary to control the relative amounts of solid material and liquid delivered to the cutting assembly  10 , for example, to obtain a mixture having a desired consistency, viscosity, etc., for processing by the assembly  10 . In addition or alternatively, it may be desirable or necessary to separately deliver additional liquid to the assembly  10  apart from the solid material or mixture. One such example is the dispersion and dissolving of solid materials in a liquid to produce a sol, gel, slurry, paste, etc., a particular example of which is the production of polymer-water suspensions used to displace oil in enhanced oil recovery (EOR) and oil sands tailings treatment applications. To produce such suspensions, a mixture of water and solid particles of a water-soluble polymeric material can be introduced into a Comitrol® machine, where the polymer particles are comminuted and then dissolved in the water. In such applications, there are occasions where the final suspension exhibits more desirable properties for its intended use if it contains more water than what may be needed or optimal for cutting and dissolving the polymer particles. Alternatively or in addition, it can be advantageous to rinse the knives of the cutting head during operation to avoid a build-up of comminuted polymer particles between the knives. In either case, Comitrol® machines have been modified with nozzles fed by external water lines or manifolds to direct high pressure water at the outer perimeter of their cutting heads. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0008]    The present invention provides machines and methods adapted to process, for example, to reduce the size of, disperse, or homogenize, a variety of materials and compositions, a nonlimiting example of which is the dispersion and dissolving of polymeric materials in a liquid to produce a suspension, sol, gel, slurry, paste, etc. 
         [0009]    According to one aspect of the invention, a material processing machine includes an enclosure comprising a fluid inlet and a channel fluidically connected to the fluid inlet, and a cutting assembly within the enclosure. The cutting assembly includes a cutting head and an impeller adapted for rotation within the cutting head about an axis thereof. The cutting head has a support member and knives disposed below the support member, and the support member includes at least a first passage fluidically connected to the channel of the enclosure to receive therefrom a liquid flowing in the channel and to conduct the liquid through the support member. 
         [0010]    Additional aspects of the invention include kits that include an enclosure and cutting head of the type described above to modify or retrofit an existing machine, as well as methods of using a machine to process a solid material by reducing the size of the material and dispersing the material in a liquid. Such methods include cutting the material with knives located along a perimeter of an annular-shaped cutting head and causing the cut material to flow radially outward from the cutting head through gaps between the knives, and flowing a liquid through passages in the cutting head that cause the liquid to cascade around the knives of the cutting head in an axial direction of the cutting head. 
         [0011]    A technical effect of the invention is that, when dispersing, dissolving, or otherwise mixing a solid material in a liquid, additional liquid can be delivered to the cutting head in an efficient and effective matter, and without the need for nozzles, external waterlines, manifolds, and a source of high pressure water. The additional liquid delivered to the cutting head can be utilized for various purposes, for example, to modify the nature of the resulting product, for example, by increasing its fluidity and/or inhibiting the build-up of particles between knives. 
         [0012]    Other aspects and advantages of this invention will be better appreciated from the following detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIGS. 1 and 2  represent a commercial configuration of a COMITROL® machine known in the prior art. 
           [0014]      FIGS. 3 and 4  illustrate nonlimiting configurations for a cutting head suitable for use with the machine of  FIGS. 1 and 2 . 
           [0015]      FIGS. 5 and 6  schematically represent two partial sectional views of an enclosure and cutting head suitable for installation and use with the machine of  FIGS. 1 and 2 . 
           [0016]      FIG. 7  schematically represents an isolated view of the enclosure depicted in  FIGS. 5 and 6 . 
           [0017]      FIG. 8  schematically represents an isolated view of a distribution ring depicted in  FIGS. 5 and 6 . 
           [0018]      FIG. 9  schematically represents an isolated view of an upper support ring depicted in  FIGS. 5 and 6 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]      FIGS. 5 through 9  schematically represent various nonlimiting views of a material processing machine and components thereof within the scope of the invention. The machine described below can be any of various types of machines, as nonlimiting examples, the Comitrol® machine depicted in  FIGS. 1 through 4  or one or more of the machines disclosed in U.S. Pat. Nos. 4,660,778, 4,610,397, 4,657,190, and 5,201,469, and can utilize certain components thereof, for example, the components of the Comitrol® machine depicted in  FIGS. 1 through 4 .  FIGS. 5 through 9  illustrate a particular nonlimiting embodiment of the invention that includes components that can be modifications of or in addition to components of the machine represented in  FIGS. 1 through 4 . Therefore, the following discussion will focus primarily on certain aspects of the embodiment represented in  FIGS. 5 through 9 , whereas other aspects not discussed in any detail may be, in terms of structure, function, materials, etc., essentially as was described for the machine and components of  FIGS. 1 through 4 . In  FIGS. 5 through 9 , consistent reference numbers are used to identify components that are the same or functional equivalents of components identified in  FIGS. 1 through 4 , but with a numerical prefix (1) added to distinguish components depicted in  FIGS. 5 through 9  from their counterparts depicted in  FIGS. 1 through 4 . 
         [0020]    To facilitate the description of embodiments of the invention provided below, relative terms, including but not limited to, “vertical,” “horizontal,” “upper,” “lower,” “above,” “below,” etc., may be used in reference to the orientation of the machine as represented in  FIGS. 1 and 2 , and therefore are relative terms that help to describe the embodiments but should not necessarily be interpreted as limiting the scope of the invention. 
         [0021]      FIGS. 5 and 6  are partial cross-sectional views in which can be seen an enclosure  118  and cutting head  126 . The cutting head  126  is an annular-shaped subcomponent of a cutting assembly that further includes an impeller, which is not depicted in  FIGS. 5 and 6  for purposes of clarity but would be assembled with the cutting head  126  as shown and described in reference to  FIGS. 1 and 2 . Consistent with  FIG. 3 , the cutting head  126  comprises a backing ring assembly  134  that secures a pair of upper and lower knife holding rings  130  and  132  to, respectively, a pair of upper and lower members configured in the form of rings  136  and  138  that are axially spaced apart by circumferentially-spaced posts  139 . Consistent with  FIG. 4 , the knife holding rings  130  and  132  are adapted to mount and secure knives (not shown) therebetween, position the knives along the inner perimeter of the cutting head  126 , and generally provide the knives  40  with a radial and axial orientation relative to the cutting head  126 . The backing ring assembly  134  comprises a pair of upper and lower retainer rings  135 A and  135 B that are axially spaced apart by circumferentially-spaced posts  137 , and the retainer rings  135 A and  135 B secure, respectively, the upper and lower knife holding rings  130  and  132  within recesses formed in the upper and lower support rings  136  and  138 . Similar to the support rings  36  and  38  of the cutting head  26  shown in  FIGS. 1 through 3 , the upper and lower rings  136  and  138  serve to support other components of the cutting head  126 , and as such the rings  136  and  138  will be hereinafter referred to as support rings. Though described as “rings,” it is foreseeable that the support rings  136  and  138  could have other shapes consistent with their role within a cutting head that surrounds a rotating impeller. 
         [0022]    In view of the above, it should be understood that a machine equipped with the cutting head  126  is adapted to process material delivered to an impeller coaxially mounted for rotation within the cutting head  126 , and that such material can be delivered via a feed tube  113  coupled to the enclosure  118  and supplied by a feed hopper (not shown), though other feeding means are also foreseeable and within the scope of the invention, for example, feed screws.  FIGS. 5 and 6  represent the enclosure  118  as an assembly that comprises a housing  119 , a channel ring  150 , and a distribution ring  152 . Together, the channel and distribution rings  150  and  152  define a channel  154  therebetween that is preferably annular in shape, continuous, and circumscribes the feed tube  113  at an upper end of the enclosure  118 , as evident from  FIG. 7 . O-ring grooves are provided for receiving seals (not shown) capable of achieving fluid-tight seals between the enclosure  118 , channel ring  150 , and distribution ring  152 . A liquid, for example, water, can be delivered to the channel  154  via an inlet  156  coupled to the channel ring  150  ( FIG. 5 ). As seen in  FIG. 8 , the distribution ring  152  has at least one and preferably multiple passages in the form of slots  158  that pass entirely through the axial thickness of the ring  152 , so that a liquid that enters the channel  154  through the inlet  156  is able to pass through the distribution  152  at multiple locations around the perimeter of the cutting head  126 . 
         [0023]      FIGS. 5 and 9  represent the upper support ring  136  of the cutting head  126  as having holes  166  that pass entirely through its axial thickness for receiving upper ends of the posts  139  that connect the upper support ring  136  to the lower support ring  138 , as evident in  FIG. 5 . The distribution ring  152  can be seen in  FIG. 8  as having holes  160  that pass entirely through its axial thickness to provide access to the upper ends of the posts  139 .  FIGS. 5, 6 and 9  further represent the upper support ring  136  as differing in part from the upper support ring  36  depicted in  FIG. 3  by having passages in the form of slots  162  and holes  164 . The slots  162  are configured to intersect an upper axial surface of the support ring  136  and an outer peripheral surface of the ring  136 , such that each slot  162  has two portions that intersect each other within the ring  136 , for example, at roughly ninety degrees.  FIGS. 5 and 6  depict that there are multiple holes  164  that intersect each slot  162  from the lower axial surface of the ring  136 . 
         [0024]      FIGS. 5 and 6  represent the channel ring  150  and distribution ring  152  of the enclosure  118  and the upper support ring  136  of the cutting head  126  as axially aligned through an annular-shaped opening in the enclosure  118 , such that the distribution ring  152  and upper support ring  136  axially abut each other. As evident from  FIG. 6 , the slots  162  and holes  164  of the support ring  136  can be aligned with the slots  158  of the distribution ring  152 . In combination, the slots  158  and  162  and holes  164  enable a liquid within the channel  154  of the channel ring  150  to flow through the distribution ring  152  and then through the support ring  136 , from which the liquid flows onto and around other components of the cutting head  126 , including the knives thereof. 
         [0025]    On the basis of the above, a material processing machine equipped with the enclosure  118  and cutting head  126  can be employed to reduce the size of a solid material by introducing the material to a impeller (e.g., the impeller  24  of  FIGS. 1 and 2 ) rotating within the cutting head  126  to comminute the material with knives (e.g., the knives  40  of  FIGS. 1, 2 and 4 ) of the cutting head  126  and cause the comminuted material to flow radially outward through gaps between the knives. Furthermore, such a material processing machine is also configured to introduce a liquid into the channel  154  within the enclosure  118  via the fluid inlet  156  so that the liquid flows through the distribution and support rings  152  and  136 . The flow of the liquid can generally be characterized as a waterfall or cascade in a downward direction generally parallel to the axis of the cutting head  126  and to the axis of rotation of the impeller  124  within the cutting head  126 . In this manner, the liquid introduced into the enclosure  118  can deliver any additional liquid required by the comminution process performed within the enclosure  118 , as well as serve to remove any accumulation of material on or between the knives of the cutting head  126 . It should be understood that a material processing machine equipped with the enclosure  118  and cutting head  126  described above can be a new build, or the enclosure  118  and cutting head  126  could be provided in the form of a kit used to modify or retrofit an existing machine. 
         [0026]    The amount of liquid supplied can depend on the requirements of the particular process, including composition of the material being processed and the nature of the resulting product, for example, a suspension, sol, gel, slurry, paste, etc. An application in which the enclosure  118  and cutting head  126  configured as described above are believed to provide particular benefits is the production of a polymer-water suspension used to displace oil in enhanced oil recovery (EOR) and oil sands tailings treatment applications, in which case the machine serves to cut and preferably comminute polymer particles and simultaneously mix, disperse, and/or dissolve the comminuted particles in water. Such processes are disclosed in U.S. Pat. Nos. 4,529,794, 4,603,156, 4,640,622, 4,778,280, 4,874,588, 7,048,432, 7,794,135, 8,186,871, and 8,322,922, whose contents are incorporated herein by reference. Other applications are also foreseeable, particularly where a liquid is to be added to a material after particles of the material have been reduced in size. 
         [0027]    While the invention has been described in terms of specific embodiments, it is apparent that other forms could be adopted by one skilled in the art. For example, the physical configurations of the components and machine could differ from those shown. As nonlimiting examples, the invention is applicable to other Comitrol® machines, such as the Comitrol® Model 1700 or 9300, as well as other material processing and size-reduction machines. Accordingly, it should be understood that the invention is not limited to any embodiment described herein or illustrated in the drawings. It should also be understood that the phraseology and terminology employed above are for the purpose of describing the illustrated embodiments, and do not necessarily serve as limitations to the scope of the invention. Therefore, the scope of the invention is to be limited only by the following claims.