Abstract:
A materials classifying cyclone with at least one vibrator for transmitting generated vibrations into the downwardly swirling slurry of materials to interrupt the flow pattern thereof so that some of the smaller particles trapped in the outer portions of the slurry are freed for movement into the vortex of the cyclone to increase the operating efficiency of the cyclone. In a first embodiment, the cyclone has a solid metallic conical housing with the vibrator attached to the periphery of the housing. In a second embodiment, a plurality of longitudinal struts in spaced apart relationship provide the conical housing with open sides with the vibrator mounted on one of the struts which transmit the vibrations to abrasion resistant liners mounted in the housing. In still another embodiment, the vibrator is coupled to an abrasion resistant liner which is exposed in one of the open spaces of the conical housing.

Description:
CROSS REFERENCE TO A RELATED APPLICATION  
       [0001]     This application is a continuation-in-part of co-pending application entitled Cyclone Having a Vibrating Mechanism, Ser. No. 11/291,281 filed Dec. 2, 2005 by the same applicant. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     This invention relates in general to cyclones and more particularly to cyclones having a vibration system for improving the separation of fine particles from a swirling slurry of materials being classified in the cyclone.  
         [0004]     2. Description of the Prior Art  
         [0005]     Cyclones are mechanisms used in various industries to separate different sized particles of materials that are fed as a slurry into the inlet of the cyclone. In the mineral processing industries such as for example in the processing of copper, iron ore, lead/zinc, gold, coal and the like, a plurality of large cyclones are typically carried in mounting bases arranged in a cluster over a “tub”. Each of the cyclones are in circuit with grinding mills and a slurry formed of a liquid, often times water, and the mineral to be classified is fed into the inlet of the cyclone. The larger, and therefore heavier materials in the slurry exit through an underflow outlet at the bottom of the cyclone and are returned to the grinding mill for reprocessing and are subsequently returned to the cyclone. The smaller, and therefore lighter materials are carried upwardly in a vortex created within the cyclone and exit through an overflow outlet nozzle at its upper end.  
         [0006]     The primary components of a cyclone include an inlet housing having a feed duct, a cylindrical head section, a head section cover plate with a vortex finder located centrally in the cover plate. A downwardly tapering conical housing depends from the head section and an apex cone is located at the lower end of the conical housing with the heavy material underflow outlet being connected to the lower end of the apex cone. The overflow outlet nozzle is coupled to the vortex finder and suitable ducts are provided to carry away the slurry containing the lighter materials. In some cyclones, the internal surfaces of the various components thereof are provided with replaceable liners which help prevent the cyclone components from being destroyed by the highly abrasive nature of the materials being classified therein.  
         [0007]     The feed duct of a cyclone, which is often referred to as an involute, receives the slurry at high velocity from the grinding mill and directs it tangentially into the cylindrical inlet head section of the cyclone. As the slurry swirls around in the head section, centrifugal force will keep the slurry adjacent the sidewalls of the cyclone as it moves downwardly under the influence of gravity into the conical housing of the cyclone. Also, centrifugal force will cause the larger particles of the materials being classified to migrate to the outside of the slurry at a relatively rapid rate and the finer particles will migrate at a comparatively slower rate. Therefore, a portion of the finer particles will be carried in the inner portions of the slurry and some will migrate to the outer portion thereof. The larger particles the will move downwardly and will exit the cyclone through the underflow outlet. The lighter materials located in the inner portion of the slurry along with the liquid carrying them will enter the vortex created within the apex cone and will move upwardly through the center of the conical housing into the vortex finder and exit the cyclone through the overflow outlet.  
         [0008]     There is not a clear demarcation between the larger and smaller particles of the materials within the swirling slurry and some of the lighter particles are located within the outer portion of the slurry along with the larger particles. An undesirable amount of the lighter particles that are located in the outer portion of the slurry become trapped therein and exit the cyclone along with the larger particles through the underflow outlet of the cyclone. This keeps the operating efficiency of cyclones below an ideal level, which effects the entire system including the grinding mill, the pumps that supply the slurry to the cyclones and the cyclones themselves. The resulting low efficiency of the system effects the time, energy usage, the costs for processing the materials, and of course the longer a system must operate to process a given quantity of material the greater the wear will be on the system components.  
         [0009]     To the best of my knowledge, no prior art mechanism or method has been devised to help release the smaller particles which become trapped in the downwardly spiraling slurry within a cyclone. Therefore, a need exists for a new and useful mechanism and method for use in a materials classifying cyclone to reduce the quantity of small particles trapped in the outer portions of the slurry so that they can enter the vortex of the cyclone rather than exiting therefrom along with the larger particles.  
       SUMMARY OF THE INVENTION  
       [0010]     The present invention discloses cyclones having at least one vibrating device attached thereto which is operated to generate vibrations in the downwardly tapering conical housings of the cyclones. The vibrations are transmitted into the downwardly spiraling slurry of materials being processed in the cyclones to release some of the smaller particles which would otherwise remain trapped within the slurry.  
         [0011]     In a first embodiment, a cyclone of conventional configuration is modified by having at least one vibrating device welded or otherwise affixed to the metal housing of the downwardly tapering conical housing thereof. Vibrations generated by the vibrating device are transmitted through the side walls of the conical metal housing and the replaceable liners into the slurry. In this manner the normal flow patterns of the slurry are interrupted by bouncing both the larger and smaller particles of the materials being classified off of the interior surface of the liners so that at least some of the smaller particles which would otherwise be trapped in the slurry will be free to enter the vortex created within the cyclone.  
         [0012]     In a second embodiment, at least one vibrating device is mounted on an especially configured cyclone of the type disclosed in my co-pending U.S. patent application Ser. No. 11/087,998, filed Mar. 24, 2005 for a Cyclone With In-situ Replicable liner Mechanism and Method For Accomplishing Same. This special cyclone includes, among other things, an open-sided downwardly tapering conical housing in place of the all metal housing of conventionally configured cyclones as discussed above in the first embodiment of the present invention. The open-sided conical housing includes a ring-shaped flange which circumscribes its open upper end and a sleeve at its lower apex end. The ring and sleeve are interconnected by a plurality of struts each of which is shown herein to be an assembly formed of a pair of angle beams arranged in a spaced apart relationship with liner support plates mounted there between. The replaceable liners used in this open-sided conical housing are of truncated conical configuration and are manufactured with a rigid metallic layer to which an abrasion resistant material such as urethane is affixed. In a first configuration, the replaceable liners are formed with the rigid metallic layer being an external element with the abrasion resistant material bonded to the interior surface thereof. In a second configuration, the replaceable liners are formed with the rigid metal layer being an internal element which is imbedded within the abrasion resistant material. The liner support plates mounted in the strut assemblies are in engagement with the replaceable liners. As mentioned above, at least one vibrating device is mounted on this especially configured cyclone to free some of the small particles trapped in the slurry so that they can enter the vortex created within the cyclone. In a first configuration, the vibrating device is mounted on one of the struts so that the vibrations generated by the device are transmitted through the struts and the liner support plates to the replaceable liners. In a second configuration, the replaceable liners are formed with at least one protruding rib to which the vibrating device is mounted. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is an elevational view of a conventional cyclone having vibrating mechanisms mounted on the sidewall of the conical housing of the cyclone in accordance with a first embodiment of the present invention.  
         [0014]      FIG. 2  is an enlarged fragmentary sectional view taken along the line  2 - 2  of  FIG. 1 .  
         [0015]      FIG. 3  is fragmentary elevational view of an especially configured open-sided cyclone in which the vibrating mechanisms are mounted thereon in accordance with a second embodiment of the present invention.  
         [0016]      FIG. 4  is an enlarged fragmentary sectional view taken along the line  4 - 4  of  FIG. 3 .  
         [0017]      FIG. 5  is an enlarged fragmentary view of a cyclone similar to that shown in  FIG. 3  and showing the vibrating mechanisms as being mounted thereon in accordance with a third embodiment of the present invention.  
         [0018]      FIG. 6  is an enlarged fragmentary sectional view taken along the line  6 - 6  of  FIG. 5 . and showing a first attachment means for mounting of the vibrating mechanism.  
         [0019]      FIG. 7  is a sectional view similar to  FIG. 6  and showing a second attachment means for mounting of the vibrating mechanism.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0020]     Referring more particularly to the drawings,  FIG. 1  shows a cyclone which is indicated generally by the reference numeral  10 . The cyclone  10  is of conventional configuration which is in common use especially in the mineral processing industry. The major components of the cyclone  10  include a cylindrical head section  12  having an inlet duct  14  through which the material to be classified is directed tangentially into the head section at high velocity. The head section  12  has a cover plate  16  closing its open upper end with a nozzle  18  extending upwardly from the cover plate to form the overflow outlet  20  of the cyclone  10 . The head section  12  is open at its lower end and a downwardly tapering conical housing  22  depends there from with an apex cone  24  extending through the open lower end of the conical housing to form the underflow outlet  26  of the cyclone  10 . An optional anti-splash apron  28  can be mounted on the lower end of the apex cone  24 . It will be appreciated that the materials that are classified within cyclones are oftentimes abrasive and to minimize the destructive forces of such an abrasive environment, they are provided with internally mounted abrasion resistant liners with a fragmentary portion of one of such liners  30  being shown in  FIG. 2 . Abrasion resistant liners of various types are used as determined by the type of materials being processed and by manufacturer&#39;s preferences. The liner  30  shown in  FIG. 2  includes a metallic substrate  32  of conical configuration with the abrasion resistant material  34  bonded to the interior surface thereof. Another abrasion resistant liner configuration is disclosed as will hereinafter be described in detail.  
         [0021]     To insure a clear understanding of the present invention, a brief description of a typical material classification installation (not shown) and the operation of the cyclone  10  will now be presented. A cyclone is a mechanism that is used in various industries to classify, that is separate, different sized particles of materials that are fed as a slurry into the inlet of the cyclone. In the mineral processing industries such as for example in the processing of copper, iron ore, lead/zinc, gold, coal and the like, a plurality of large cyclones are typically carried in mounting bases arranged in a cluster over a “tub”. Each of the cyclones are in circuit with grinding mills (not shown) and a slurry formed of a liquid, usually water, and the material to be classified is supplied to the cyclones. The inlet, or feed duct  14  of the cyclone  10 , which is often referred to as an involute, receives the slurry at a high velocity and directs it tangentially into the cylindrical inlet head section  12  of the cyclone. As the slurry swirls around in the head section, centrifugal force will keep the slurry adjacent the sidewalls of the cyclone as it moves downwardly under the influence of gravity into the conical housing  22  of the cyclone. Also, centrifugal force will cause the larger and therefore heavier particles of the materials being classified to migrate to the outside of the slurry at a relatively rapid rate and the smaller and therefore lighter particles will migrate at a comparatively slower rate. Therefore, some of the smaller particles will remain in the inner portions of the slurry and some will migrate into the outer portion thereof. The particles located in the outer portion of the slurry will move downwardly through the apex cone  24  and will be discharged through the underflow outlet  26  of the cyclone  10 . The portion of the smaller materials located in the inner portion of the slurry along with the liquid carrying them will enter a vortex that is created within the apex cone  24  and will move upwardly through the center of the conical housing  22 , through the cylindrical head section  12  and will exit the cyclone  10  through the overflow outlet  20 .  
         [0022]     As indicated above, there is not a clear demarcation between the larger and smaller particles of the materials within the swirling slurry and some of the smaller particles will be located within the outer portion of the slurry along with the larger particles. An undesirable amount of the smaller particles that are located in the outer portion of the slurry become trapped therein and exit the cyclone  10  along with the larger particles through the underflow outlet  26  of the cyclone and this keeps the operating efficiency of cyclone below an ideal level.  
         [0023]     In accordance with a first embodiment of the present invention, the cyclone  10  includes at least one vibrating device  36  which is affixed to the outer surface of the conical housing  22  as seen in  FIGS. 1 and 2 . The vibrator  36 , which may be affixed in any suitable manner, is shown as being attached to a nut plate  38  by bolts  40  which are mounted in threaded bores  42  (one shown) formed in the plate  38 . The nut plate  38  is affixed to the conical housing  22  such as by welding. The vibrating device  36  is operated to generate vibrations in the metallic body of the conical housing  22  of the cyclone  10  and those vibrations are transmitted through the abrasion resistant liners  30  located in the housing  22  and into the downwardly spiraling slurry being processed in the cyclone  10 . In this manner the normal flow patterns of the slurry are interrupted by bouncing both the larger and smaller particles of the materials being classified off of the interior surface of the liners  30  so that at least some of the smaller particles which would otherwise be trapped in the slurry will be freed to enter the vortex created within the cyclone  10 .  
         [0024]      FIG. 3  shows a second embodiment as including a special cyclone  44  of the type disclosed in my previously mentioned co-pending U.S. patent application. This special cyclone  44  includes plurality of swing bolts  46 , or other suitable means such as removable tension rods (not shown), which mount the cover plate  48  on the top of the head section  50  and also mount a special open-sided downwardly tapering conical housing  52  below the head section  50 . The open-sided conical housing  52  includes a flange  54  which circumscribes its open upper end and a sleeve  56  at its lower apex end. The ring-shaped flange  54  and the sleeve  56  are interconnected by a plurality of strut means  58  which may be of any suitable configuration such as I-beams, circular in cross-section beams, or the like. Each of the struts are shown herein as an assembly formed of a pair of angle beams  60  connected to each other in a parallel spaced apart relationship by suitable bolts  61  with liner support plates  62  mounted there between. In that the sides of the conical housing  52  are open, the liners provided therein are seen to include an upper abrasion resistant liner  64 , a middle abrasion resistant liner  66  and a lower abrasion resistant liner  68  with all three being of truncated conical configuration. As described above in the description of the abrasion resistant liners  30  of the first embodiment, the abrasion resistant liners  64 ,  66  and  68  are similar, in that they are formed with metal substrates  70  having a suitable abrasion resistant material  72  bonded to the inner surface thereof as shown in the fragmentary sectional view of the liners  64  and  66  in  FIG. 4 .  
         [0025]     The liner support plates  62  mounted in the strut assemblies  58  are shown in  FIG. 4  as having slotted holes  63  (one shown) through which the mounting bolts  61  pass to mount the plates in the strut assemblies. In this manner, the liner support plates  62  extend into engagement with the liners  64 ,  66  and  68  and are adjustable for centering and aligning the liners and provide contiguous engagement of the plates with the metal substrates  70  of the abrasion resistant liners. At least one vibrating device  36  is mounted by a pair of the bolts  61  on one of the strut assemblies  58 . The vibrations generated by the vibrating device  36  are transmitted through the angle beams  60  of the strut assembly  58  on which it is mounted and the liner support plates  62  to the abrasion resistant liners  64 ,  66  and  68  to free some of the small particles trapped in the slurry, in the manner hereinbefore described.  
         [0026]      FIG. 5  shows a third embodiment of the present invention as including a special cyclone  74  which is a modified version of the previously described cyclone  44 . The cyclone  74  has the same swing bolts  46  and head section  50 , and a modified open-sided conical housing  76 . The conical housing  76  includes the ring-shaped flange  78  that circumscribes the open upper end of the housing and the sleeve  80  located at the lower end of the housing. The flange and sleeve are interconnected by the strut means  82  which are similar to the previously described strut means  58  in that they include a spaced apart pair of angle beams  84 . However, the angle beams  84  are not connected to each other and the liner support plates  62  mounted between the angle beams  60  of the prior strut means  58  are omitted.  
         [0027]     Especially configured upper, middle and lower abrasion resistant liners  88 ,  90  and  92  respectively, are of different sizes with the upper liner being the largest and the middle and lower liners decreasing in size so that they can be mounted in the open-sided conical housing  76 . Although the liners are of different sizes, they are of similar configuration, and the following description of the liner  88  as seen in  FIG. 6  will be understood to apply to the other liners  90  and  92 .  
         [0028]     The liner  88  includes a perforated rigid structure  94  which is embedded within abrasion resistant material  96 . The rigid structure  94  may be made of any suitable material such as metal, which is formed into the desired truncated conical configuration and the abrasion resistant material  96 , which may be urethane, rubber, ceramic or the like, is cast around the rigid structure. The casting of the abrasion resistant material  96  includes the integral formation of laterally protruding ribs  98  which are formed of the liner material and extend longitudinally of the liner  88 . The typical liner  88 , discussed above is a first embodiment and  FIG. 7  shows a second embodiment which is identified as liner  88   a . The liner  88   a  is similar to the liner  88  but differs there from by having its protruding ribs  98   a  (one shown) cast around a rigid strip  100  which is formed of the same material as the rigid structure  94   a , and is suitably attached thereto such as by welding.  
         [0029]     The cyclone  74  includes at least one vibrating device  102  which may be mounted on a selected one of the liners  88 ,  90  and  92  by any suitable means. One disclosed type of attachment means is seen best in  FIG. 6  as being in the form of an especially configured C-clamp  104  that includes a clevis  106  having a cross member  108  from the opposite ends of which extend a spaced apart pair of parallel arms  110  and  112 . A pair of studs  114  (one shown in  FIG. 6 ) extend from the cross member  108  of the clevis  106  and the vibrator  102  is mounted on the studs and secured thereto by suitable nuts  116  (one shown). The clevis  106  straddles the rib  98  of the liner  88  and is clamped thereto by a screw  118  that is carried in the arm  112  of the clevis for threaded movement into clamping engagement with one side of the rib  98 . The other arm  110  of the clevis  106  is formed with inwardly facing teeth  120  which penetrate the opposite side of the rib  98  to secure the vibrating device  102  and the C-clamp  104  against movements that could result from the generated vibrations. A second disclosed type of attachment means is shown in  FIG. 7  to include a clevis  122  having a cross member  124  from the opposite ends of which extend a spaced apart pair of parallel arms  126  and  128 . A pair of studs  130  (one shown) are carried in the cross member  124  of the clevis  122  and the vibrator  102  is mounted on the studs and secured thereto by suitable nuts  132  (one shown). The clevis  122  straddles the rib  98   a  of the liner  88   a  with arms  126  and  128  disposed adjacent opposite sides of the rib. A bore  134  is provided in each of the arms  126  and  128  so as to align with a bore  136  formed transversely through the rib  98   a  and a bolt  138  passes through the bores  134  and  136  and a nut  140  is carried on the bolt to secure the clevis  122  and vibrator  102  to the liner  88   a.    
         [0030]     It will be understood that the vibrators  36  and  102  may be electrically, hydraulically or pneumatically operated devices with one suitable vibrator being model No. CV-35 marketed under the trademark VIBROLATOR by the Martin Engineering Company, One Martin Place Neponset Ill. 61345-9766.  
         [0031]     While the principles of the invention have now been made clear in illustrated embodiments, many modifications will be obvious to those skilled in the art which do not depart from those principles. The appended claims are therefore intended to cover such modifications within the limits only of the true spirit and scope of the invention.