Abstract:
A process for the comminution and dehydration of animal waste and/or parts by feeding the animal waste and/or parts into a cyclonic, dehydrating comminuter facilitates the further processing of the comminuted and dehydrated animal waste discharged from the comminuter. Both the comminuted and dehydrated material and the air flow discharged from the cyclonic comminuter are sterilized to remove pathogens therefrom. The rate at which the animal waste and/or parts material is fed into the cyclonic comminuter. is directly related to the moisture content of the comminuted and dehydrated material discharged from the material discharge opening of the comminuter. Preferably, the moisture content of the discharged material is in the range of 25% to 35% to facilitate the pelletizing of the discharged material after being sterilized. Other precesses, however, can require the drying of the discharged material to about 10%. An air flow control mechanism is provided for the cyclonic comminuter to enhance the ability to control the discharge of air from the comminuter. The control is provided with adjustable vanes actuated from a actuator projecting outwardly from the comminuter to permit an easy adaptation to automated controls to restrict the size of the air discharge opening from the comminuter.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a division of U.S. patent application Ser. No. 09/338,147, filed Jun. 23, 1999 abandoned, and claims domestic priority on U. S. Provisional Patent Application Ser. No. 60/090,494, filed on Jun. 24, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates generally to the comminution and dehydration of animal wastes and waste animal parts utilizing a cyclonic comminuter and, more particularly, to the process of treating animal waste products, including manure, as a pre-treatment conditioner for further appropriate treatment of the output material. 
     An environmentally acceptable treatment of animal waste, including animal manure and waste animal parts, has become an important issue. Feed lots, whether used for the production of hogs, cattle, chickens or the like, create a concentrated collection of manure at one geographic area. The disposal of dead animals and waste animal parts from slaughter operations presents a similar environmental problem. One solution is the processing of animal waste material for sale as animal feed or as compost. Such processes are known, but have not yet been proven to be commercially feasible. 
     Accordingly, a process, method and apparatus for pre-treating animal waste products to create an output that is acceptable for further processing treatment in a cost effective way would be highly desirable. Such a process must also be effective in the removal of pathogens from the waste product being treated. 
     SUMMARY OF THE INVENTION 
     It is an object of this invention to provide a method of processing animal waste to effect a comminution and a dehydration thereof by feeding said animal waste into a cyclonic comminuter. 
     It is another object of this invention to provide a method of processing animal waste including the steps of feeding the animal waste into the air flow of a cyclonic dehumidifying comminuter to comminute said animal waste and to effect dehydration thereof, the comminuted and dehydrated animal waste being discharged through a material discharge opening at a bottom portion of the cyclonic comminuter while moisture laden air flow is discharged through an air discharge opening; 
     sterilizing the discharged air flow after being exhausted from said comminuter to remove pathogens therefrom before being released to the atmosphere; and 
     passing the comminuted and dehydrated animal waste through a sterilization chamber after being discharged from the cyclonic comminuter to destroy pathogens therein. 
     It is a feature of this invention that the flow rate of the animal waste through the cyclonic comminuter can be controlled to establish a desired moisture content of the comminuted and dehydrated animal waste being discharged from the cyclonic comminuter. 
     It is an advantage of this invention that the comminuted and dehydrated animal waste being discharged from the cyclonic comminuter can be further processed by pelletizing for shipment thereof to a remote location. 
     It is another feature of this invention that an auger can be used for metering the flow of animal waste into the infeed of the cyclonic comminuter. 
     It is another advantage of this invention that the auger used for metering the flow of animal waste into the infeed of the cyclonic comminuter will mix different supplies of animal wastes containing different moisture levels for feeding into the cyclonic comminuter. 
     It is still another feature of this invention that the comminuted and dehydrated animal waste and the moisture laden air flow discharged from the cyclonic comminuter are sterilized to remove pathogens therefrom. 
     It is yet another feature of this invention that the animal waste can be manure or animal parts. 
     It is still another object of this invention to provide an air flow control mechanism to control the discharge of air from the cyclonic comminuter. 
     It is yet another feature of this invention that the air flow control mechanism has an adjustable damper control that restricts the size of the discharge opening for the air flow from the cyclonic comminuter. 
     It is yet another advantage of this invention that the adjustable damper control is easily adaptable to automated control mechanisms. 
     These and other objects, features, and advantages are accomplished according to the instant invention by providing a process for the comminution and dehydration of animal waste and/or parts by feeding the animal waste and/or parts into a cyclonic, dehydrating comminuter to facilitate the further processing of the comminuted and dehydrated animal waste discharged from the comminuter. Both the material and the air flow discharged from the cyclonic comminuter are sterilized to remove pathogens therefrom. The rate at which the animal waste and/or parts material is fed into the cyclonic comminuter is directly related to the moisture content of the comminuted and dehydrated material discharged from the material discharge opening of the comminuter. Preferably, the moisture content of the discharged material is in the range of 25% to 35% to facilitate the pelletizing of the discharged material after being sterilized. Other precesses, however, can require the drying of the discharged material to about 10%. An air flow control mechanism is provided for the cyclonic comminuter to enhance the ability to control the discharge of air from the comminuter. The control is provided with adjustable vanes actuated from a actuator projecting outwardly from the comminuter to permit an easy adaptation to automated controls. to restrict the size of the air discharge opening from the comminuter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The advantages of this invention will be apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein: 
     FIG. 1 is a perspective view of a comminuting/dehydrating machine incorporating the principles of the instant ivention; 
     FIG. 2 is a schematic top plan view of the damper mechanism controlling the flow of air being discharged from the sleeve; 
     FIG. 3 is a schematic side elevational view of the damper shown in FIG. 2; 
     FIG. 4 is a perspective view of the comminuting/dehydrating machine shown in FIG. 1, but with a sterilizing apparatus positioned to receive material discharged from the conical housing; 
     FIG. 5 is a perspective view of a rasp bar to depict the configuration of each of the plurality of rasp bars lining the interior of the periphery of the cylindrical portion of the housing; 
     FIG. 6 is a schematic cross-sectional view of the upper portion of the air discharge sleeve to depict an alternative air flow control mechanism, one of the vanes being schematically depicted in the center of the sleeve, the remaining vanes have not been shown for purposes of clarity; 
     FIG. 7 is a top plan view of the air discharge sleeve with the air flow control mechanism in a fully closed position; 
     FIG. 8 is a side elevational view of one of the adjustable vanes; and 
     FIG. 9 is a end view of one of the adjustable vanes. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Comminuting dense material through a cyclonic comminuting/dehydrating machine, such as shown in U.S. Pat. No. 3,794,25 1, issued on Feb. 26, 1974, for a “Material Reducing System and Apparatus”, is well known in the art. A cyclonic comminuting/dehydrating machine similar to that disclosed in U.S. Pat. No. 5,236,132, is schematically depicted in the perspective views of FIGS. 1 and 4. The descriptive portions of the aforementioned U.S. Pat. No. 3,794,251 and U.S. Pat. No. 5,236,132 are incorporated herein by reference, particularly with respect to the manner and mechanism through which a cyclonic comminuting/dehydrating machine operates. 
     Such a cyclonic comminuting/dehydrating machine  10  operates to create a high velocity stream of air from a fan  11  that is directed through a conduit  12  into an inverted conical housing  15 . The stream of air is directed into a tornado-like swirling motion within the housing before being discharged out the exit opening  16  at the top center portion of the housing  15 . A damper  20  controls the flow of air through the air exit opening  16  and the depth of the swirling motion of the air within the housing  15 . Preferably, the fan  11  is driven by a power source, such as an electric motor  11   a  that is drivingly connected with the fan  11  via conventional drive transfer devices (not shown), such as belts and pulleys. Because of the noise generated by the operation of the large fan  11 , a silencer  11   b  is used to dampen the noise. 
     A cylindrical sleeve  18 , co-operable with the damper  20 , is axially movable within the housing  15  to also control the depth of cyclonic comminution of material within the housing  15 . A pair of linear actuators (not shown), which can be powered hydraulically, pneumatically or electrically, can interconnect the sleeve  18  and the sleeve support  19  forming the top wall of the cylindrical portion  17  of the housing  15  to power the movement of the sleeve  18  within the housing  15 . The positioning of the sleeve  18  deep into the housing  15  provides for greater comminution of the material fed through the conduit  12 , while a shallow penetration of the sleeve  18  into the housing allows for a more rapid exit of the swirling air from the housing  15  through the air exit opening  16  and, therefore, provides only minimal comminution of the material. 
     A discharged air recovery mechanism (not shown) can be provided to capture the discharged stream of air from the air exit opening  16  to prevent the discharge of any fractional components within the discharged air into the atmosphere to control pollution and allow the recovery of any fractional component therein, as will be discussed in greater detail below. A material infeed hopper 13 meters the flow of material into the air stream in the conduit  12  so that the material to be comminuted enters the housing  15  generally tangentially with the stream of air from the conduit  12 . Preferably, the infeed hopper  13  includes an air lock  13   a  having a rotational member that limits the escape of air from the conduit  12  while feeding material into the conduit  12  for flow into the housing  15 . 
     The housing  15  includes a cylindrical portion  17  that receives the air stream, and material flowing therein, from the conduit  12  and directs the air stream into a swirling motion within the housing  15 . Depending immediately below the cylindrical portion  17  is a conical portion  17   a  that directs the swirling air flow into decreasing-radius turns until the air can escape up through the sleeve  18 , past the damper  20  and into the discharged air recovery mechanism (not shown). The conical portion  17   a  terminates in a material discharge opening  14  at its lowermost extremity for the discharge of comminuted material from the housing  15 . 
     The cylindrical portion  17  is lined with steel rasp bars  17   b  (FIG.  5 ), which may be hardened, and when coupled with the differential forces associated with the tornado-like swirling motion of the air stream within the housing  15 , serve to comminute material fed therein through implosion, impaction and centrifugal force, on the basis of quantity and density of the material fed therein. At least the upper areas of the conical portion  17   a  preferably also have spirally arranged members (not shown) that assist in the comminution of material within the housing  15  and deflect material upwardly toward the cylindrical portion  17  to further the comminuting process. 
     As best seen in FIGS. 1-4, the damper  20  is mounted on top of the cylindrical sleeve  18  to control the flow of air discharged therethrough. The damper  20  is formed of a generally flat top plate  21  welded to a cylindrical skirt  23  to form a cap on the end of the sleeve  18 . A second flat plate  25  is rotatably supported beneath the top plate  21 , such as by a pivot bolt  29 . Both the top plate and the second plate are formed with openings  22 ,  26 , respectively, arranged adjacent the outer periphery of the plates  21 ,  25 . These openings  22 ,  26  are alignable upon rotation of the second plate  25  relative to the top plate  21  to define a variable sized discharge openings through the damper  20 . The relative rotated position of the second plate  25 . with respect to the top plate  21  defines the size of the discharge openings extending through the damper  20  for the discharge of air therethrough. When the openings  22 ,  26  are completely aligned, the maximum sized discharge opening through the damper  20  is obtained. 
     A fixed cone  27  is positioned below the second plate  25  to direct outwardly the flow of swirling air moving upwardly through the sleeve  18 , so that the air flow is directed smoothly toward the at least partially aligned openings  22 ,  26 . The fixed cone  27  is not adjustable, except that it is preferably affixed to the underside of the second plate  25  to be rotatable therewith. An actuation handle  28  is affixed to the second plate  25 , preferably through the pivot bolt  29 , and extends outwardly beyond the boundaries of the sleeve  18  to permit the rotation. of the second plate  25  to adjust the size of the openings extending through the damper  20 . 
     One skilled in the art will readily recognize that a powered mechanism (not shown) could be operatively associated with the handle  28  to permit the remote control of the rotation of the second plate  25  relative to the top plate  21 . Such a powered mechanism (not shown) could include a hydraulic, pneumatic or electric linear actuator, such as an extensible cylinder, or screw threads interconnecting the handle and either a frame reference or the skirt  23  or sleeve  18 . Alternatively, a gear, electric or hydraulic motor could also be used to rotate the valve around its center pivot shaft. 
     Referring now to FIGS. 6-9, an alternative (and preferred) embodiment. of the air flow control mechanism  30  can best be seen. The air flow control mechanism  30  includes a fixed cone  31  supported in the center of the air discharge sleeve  18  by a fixed support  32  to force the flow of air being discharged up the sleeve  18  into a circular pattern toward the outside of the sleeve  18 . The cone  31  pivotally supports a plurality of vanes  35  arranged in an overlapping configuration. Each vane  35  includes a pivot support arm  36  that engages the cone  31  and permits movement in a manner described in greater detail below. The pivot support arm  36  may require an additional bend to retain the engagement thereof with the cone  31  during movement. The body portion  37  of each vane  35  is curved, as best seen in FIG. 9, and is oriented on top of the adjacent vane  35  on one side and beneath the adjacent vane  35  on the opposing side to effect simultaneous movement of the vanes  35  as described below. 
     The air flow control assembly  30  includes an actuator mechanism  40  connected to a first actuator vane  38  on one side of the sleeve  18  and to a second actuator vane  39  on the opposing side of the sleeve  18 . The first actuator vane  38  is attached to a first actuator nut  41  having left hand threads, while the second actuator vane  39  is attached to a second actuator nut  43  having right hand threads. A crank arm assembly  45 , formed of two rods  46 ,  47  interconnected by a connector coupling  48 , is rotatably supported on the sleeve  18  and threadably mounts the two actuator nuts  41 ,  43  so that upon rotation of the crank arm assembly  45  the two nuts  41 ,  43  are translated along the length of the rod  46 ,  47  on which they are mounted toward or away from each other, depending on the direction of rotation of the crank arm assembly  45 . 
     To force the actuator nuts  41 ,  43  to translate along the corresponding rods  46 ,  47  upon rotation of the crank arm assembly  45  and to effect movement of the vanes  35 , the actuator nuts  41 ,  43  are connected to the corresponding actuator vane  38 ,  39  by a pin  49  mounted through a pair of mounting ears (not shown). The mounting ears (not shown) could be formed on either the actuator nut  41 ,  43  or on each of the respective actuator vanes  38 ,  39 . The ears (not shown) are formed with slots (not shown) so that the pins  49  can slide within the corresponding slot (not shown) as the actuator nuts  41 ,  43  effect pivotal movement of the actuator vanes  38 ,  39 . 
     In operation, the size of the discharge opening through the sleeve  18  is controlled by the rotation of the crank arm assembly  45 . By rotating the crank handle  45   a  in a clockwise direction, the left hand thread actuator nut  41  and the right hand thread actuator nut  43 , each of which are connected to the corresponding actuator vane  38 ,  39  as described above, move along the rod  46 ,  47  toward each other. This motion pulls the corresponding actuator vanes  38 ,  39  along with the actuator nuts  41 ,  43 , causing the actuator vanes  38 ,  39  to pivotally move about their respective connection with the fixed cone  31  in a generally vertical direction, creating a gap between the vanes  38 ,  39  and the circumference of the sleeve  18 . Since all of the other vanes  35  are overlapped with each other and with the actuator vanes  38 ,  39 , the generally vertical movement of the actuator vanes  38 ,  39  is transferred to the other vanes  35 , creating an annular ring opening between the vanes  35 ,  38  and  39  and the circumference of the sleeve  18 . 
     An opposite rotation of the crank handle  45   a  will cause a movement of the actuator nuts  41 ,  43  away from each other. This motion has the opposite effect to that described above, causing the actuator vanes to pivotally move downwardly toward the outer circumference of the sleeve  18 . Again, since the vanes  35 ,  38  and  39  are arranged in an overlapping configuration, all of the vanes  35 ,  38  and  39  move downwardly together, narrowing the annular gap between the vanes and the sleeve  18  through which the air is discharged. 
     As with the damper mechanism  20 , a powered mechanism (not shown) could be operatively associated with the crank handle assembly  45  to permit the remote control of the rotation thereof to move the vanes  35  up and down and vary the effective size of the air discharge opening. Such a powered mechanism (not shown) could include a hydraulic, pneumatic or electric motor that can effect an appropriate rotation of the crank arm assembly  45 , although the crank handle  45   a  would likely need to be removed. 
     The operation of the actuators (not shown) controlling the depth of penetration of the sleeve  18  within the housing  15  in conjunction with the operation of the actuator controlling the rotation of the second plate  25 , which can be accomplished either together or separately, controls the flow of air through the comminuting/dehydrating machine  10  and, therefore, extent of both the comminution of the material fed into the housing  15  and the dehydration thereof. The size of the discharge openings through the damper  20 , which is defined by the extent of alignment of the openings  22 ,  26 , can be set to a specific percentage of the maximum size discharge opening to provide the amount of air flow desired or the rotated position of the second plate  25  can be programmed to correspond to a specific material being fed into the housing  15  for comminution and dehydration. 
     The comminuter/dehydrating machine  10  partially works on the density of the material being fed into the air flow through the conduit  12  into the housing  15 , the velocity of the flow of air through the conduit  12  into the housing  15 , and the amount of vacuum found at the discharge opening  14  of the conical portion  17   a . All of these factors work together to hold the material in the housing long enough to get the desired results, expressed in terms of the fineness of comminution and the moisture content of the material. 
     Other factors in the operation of the machine  10  include the toughness, hardness, and size, and in some cases, the fibrous content of the material being treated. The control of all of these factors can be achieved by controlling two variables, controlling the flow of air and controlling the time the material is being processed in the housing  15 . The control of the depth of sleeve  18  into the housing  15  and the air flow through the sleeve  18  controls these two variables. 
     Surprisingly, a cyclonic, dehumidifying comminuting machine  10  has been found to be operable to disintegrate considerably less dense material such as manure. By controlling the level of comminution within the housing  15  through manipulating the depth of the sleeve  18  into the housing  15  and the operation of the damper  20 , the amount of comminution of the manure can be selectively controlled. This control not only permits the extent of comminution of the manure material being fed into the housing  15 , but also the extent of dehydration of the manure material. Moisture content of the treated product discharged from the comminuter  10  is an important factor in the further treatment thereof by further appropriate apparatus. 
     Referring first to FIG. 1, the apparatus for treating manure and animal waste parts can best be seen. Animal manure is generally found in two types, with bedding material, such as straw, wood shavings, sawdust or other organic material, and without bedding material. Manure with bedding material generally has a lower moisture level per given volume of material. This is particularly true with respect to chicken manure. Using chicken manure as an example, the type without bedding is usually the by-product of layer barns where the chickens are retained for the purpose of laying eggs only. 
     The comminuter/dehydration machine  10  can be positioned to receive the animal manure from a collection facility (not shown) via a conveyor mechanism (not shown), preferably an auger apparatus. The use of an auger conveyor provides the benefits of serving as a metering device to the material infeed hopper  13  and of preferably mixing the manure of the first type with the manure of the second type to provide a relatively uniform material, at least in terms of moisture content, for processing in the machine  10 . This, in turn, allows the operation of the machine to be more consistent to provide a generally uniform moisture content for the material discharged from the machine  10 . 
     One possible further treatment of the material discharged from the machine  10  is to pelletize the discharged material for shipment to a remote location. A pelletizer works most efficiently at about a 25%-35% (optimally approximately 30%) moisture content. Providing a discharged material that has a substantially lower moisture content requires the pelletizer to add moisture, usually via the application of steam to the material. Infeeding only high moisture, nonbedding manure to the machine  10  requires a longer retention time of the material within the housing  15 , and thereby reducing throughput. Another possible further treatment that will be recognized by one skilled in the art includes the removal of moisture down to about 10% or below to permit proper storage without pelletizing. This process would permit blending without other fertilizers for a rapid release of the fertilizing materials to the plants. 
     The machine  10  works at ambient temperatures, except for the increase in operating temperature relating to friction from the fan and the changes in direction from impact with the internal rasp bars  17   b  mounted on the interior periphery of the cylindrical portion  17  of the housing  15 . The moisture in the material being fed into the housing  15  through the conduit  12  is atomized as the material is being comminuted within the housing  15 . The tremendous volume of air flow generated by the fan  11  carries this atomized moisture into the sleeve  18  to be discharged from the machine  10 , thereby dehydrating the material being comminuted. The rate at which the material is fed into the housing  15  is a factor that determines the dryness of the discharged material, as well as the volume of the material being discharged. If a lower moisture content is desired in the discharged material, the feed rate of material fed into the housing  15  must be slowed. 
     The description given above with respect to chicken manure also applies to waste animal parts. The material being fed into the housing  15  will be reduced in size and various components will be separated by particle size and density. All of the material fed into the housing will exit the material discharge opening  14  at the bottom of the conical portion  17   a , except for the material that is atomized and entrained within the air flow being discharged from the housing  15  through the sleeve  18 . 
     It has been found that most of the pathogens found in the manure and waste animal parts fed into the housing  15  are discharged with the air flow through the sleeve  18 , requiring that the discharged air be captured by a collector system for further treatment before being discharged into the atmosphere. Surprisingly, tests have shown that in comminuted and dehydrated chicken manure, discharged through the material discharge opening  14  at a moisture content between 25%-30%, the content of pathogens is very low. However, if such material is going to be pelletized for shipment to a remote location, or subjected to other additional processing steps, no pathogens are permitted in this discharged material. 
     Accordingly, the comminuted and dehydrated material being discharged through the opening  14  is collected in a sterilization container  50  that is cooperatively associated with a conveyor system (not shown) for the purpose of conveying the discharged material away from the machine  10 . Such a conveyor can be of any known type, such as a belt or chain conveyor, an auger or an air delivery system. Prior to being conveyed from the sterilization container  50 , the discharged material is subjected to a sterilization procedure represented by the microwave electron tube  52  or an electric discharge mechanism (not shown) that charges a conductor grid. Such an electric discharge mechanism (not shown) creates an electrical arc between grid points which heats the discharged material to a sufficiently high temperature to kill all of the remaining pathogens. 
     One skilled in the art will readily recognize that other methods of sterilizing the discharged material can also be used, including the use of a plasma arc, ultra-violet light, steam heating. The sterilization should preferably occur immediately after the material is discharged from the opening  14  into the sterilization container  50  as no additional step would be necessary in the further processing of the discharged material, such as pelletizing. 
     It will be understood that changes in the details, materials, steps and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the invention. Accordingly, the following claims are intended to protect the invention broadly as well as in the specific form shown.