Patent Publication Number: US-7909577-B2

Title: System and method for pulverizing and extracting moisture

Description:
RELATED APPLICATIONS 
     This utility application is a divisional of and claims priority to U.S. patent application Ser. No. 11/881,680 filed Jul. 27, 2007, entitled System and Method for Pulverizing and Extracting Moisture, which claims priority to U.S. patent application Ser. No. 11/298,142 filed Dec. 9, 2005, entitled System and Method for Pulverizing and Extracting Moisture, which in turn claims priority to U.S. patent application Ser. No. 10/706,240 filed Nov. 12, 2003, and entitled System and Method for Pulverizing and Extracting Moisture, which in turn claims priority to U.S. patent application Ser. No. 09/792,061 filed Feb. 26, 2001, and entitled Pulveriser and Method of Pulverising, all of which are hereby incorporated by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to techniques for processing materials to pulverize and extract moisture. 
     BACKGROUND OF THE INVENTION 
     Numerous industries require the labor intensive task of reducing materials to smaller particles and even to a fine powder. For example, the utility industry requires coal to be reduced from nuggets to powder before being burned in power generation furnaces. Limestone, chalk and many other minerals must also, for most uses, be reduced to powder form. Breaking up solids and grinding it into powder is a mechanically demanding process. Ball mills, hammer mills, and other mechanical structures impact on, and crush, the pieces of material. These systems, although functional, are inefficient and relatively slow in processing. 
     Numerous industries further require moisture extraction from a wide range of materials. Food processing, sewage waste treatment, crop harvesting, mining, and many other industries require moisture extraction. In some industries materials are discarded because moisture extraction cannot be performed efficiently. These same materials, if they could be efficiently dried, would otherwise provide a commercial benefit. In other industries, such as waste treatment and processing, water extraction is an ongoing concern and tremendous demand exists for improved methods. Although several techniques exist for dehydrating materials, there is an increasing need for improved moisture extraction efficiency. 
     Thus, it would be an advancement in the art to provide more efficient processes for pulverizing materials and extracting moisture from materials. Such techniques are disclosed and claimed herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more particular description of the invention briefly described above will be rendered by reference to the appended drawings. Understanding that these drawings only provide information concerning typical embodiments of the invention and are not therefore to be considered limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which: 
         FIG. 1  is a side view illustrating one embodiment of a pulverizing system of the present invention; 
         FIG. 2  is a plan view illustrating the pulverizing system of  FIG. 1 ; 
         FIG. 3  is a cross-sectional side view illustrating a venturi of a pulverizing system as the venturi receives material; 
         FIG. 4  is a side view illustrating an alternative embodiment of a pulverizing system of the present invention; 
         FIG. 5  is a plan view illustrating a plan view of the pulverizing system of  FIG. 4 ; 
         FIG. 6  is a perspective view illustrating an air generator housing and outlet restrictors; 
         FIG. 7  is a cross-sectional view of one embodiment of an air generator housing; 
         FIG. 8  is cross-sectional view of a venturi and a throat resizer; 
         FIG. 9  is a block diagram illustrating the components of an alternative embodiment of a pulverizing system; 
         FIG. 10  is a block diagram illustrating an alternative embodiment of a pulverizing system of the present invention; 
         FIG. 11  is a perspective view of one embodiment of an airflow generator suitable for use with a system of the present invention; 
         FIG. 12  is a cross-sectional view of a portion of the airflow generator of  FIG. 11 ; 
         FIG. 13  is a plan view of an interior portion of the airflow generator of  FIG. 11 ; 
         FIG. 14A  is a plan view of a tail edge of a blade of the airflow generator of  FIG. 11 ; 
         FIG. 14B  is a plan view of an alternative embodiment of a tail edge of a blade of the airflow generator of  FIG. 11 ; 
         FIG. 15A  is a perspective view of a portion of the airflow generator of  FIG. 11 ; 
         FIG. 15B  is a perspective view of a portion of an alternative embodiment of an airflow generator of  FIG. 11 ; 
         FIG. 16  is a side view of a blade of the airflow generator of  FIG. 11 ; 
         FIG. 17  is a cross-sectional view of the blade of  FIG. 16 ; 
         FIG. 18  is a perspective view of a portion of the airflow generator of  FIG. 11 ; and 
         FIG. 19  is a side view of an alternative embodiment of a pulverizing system of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Reference is now made to the figures in which like reference numerals refer to like elements. For clarity, the first digit or digits of a reference numeral indicates the figure number in which the corresponding element is first used. 
     Throughout the specification, reference to “one embodiment” or “an embodiment” means that a particular described feature, structure, or characteristic is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. 
     Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Those skilled in the art will recognize that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or not described in detail to avoid obscuring aspects of the invention. 
     Referring to  FIGS. 1 and 2 , a system  10  for pulverizing and extracting moisture is shown that includes an inlet tube  12 . The inlet tube  12  includes a first end  14 , communicating with free space and an opposing, second end  16  that couples to a venturi  18 . Although reference is made herein to tubes and pipes, one of skill in the art will appreciate that all such elements may have circular, rectangular, hexagonal, and other cross-sectional shapes. Generally, circular cross-sections are desirable to facilitate fabrication and operation, but the invention is not limited to such a specific implementation. 
     The inlet tube  12  provides some distance to the venturi  18  in which material can accelerate to the required velocity. A filter (not shown) may be placed to cover the first end  14  to prevent introduction of foreign particles into the system  10 . The inlet tube  12  further includes an elongated opening  20  on an upper part thereof to allow communication with the open lower end of a hopper  22 . The hopper  22  is open at its upper end  24  to receive materials. In an alternative embodiment, the system  10  does not include a hopper  10  and material is simply inserted into the elongated opening  20  through various known conventional methods. 
     The venturi  18  includes a converging portion  26  coupled to the inlet tube  12 . The converging portion  26  progressively reduces in diameter from that of the inlet tube  12  to a diameter smaller than the inlet tube  12 . The venturi  18  further includes a throat  28  that maintains a consistent diameter and is smaller than the diameter of the inlet tube  12 . The venturi  18  further includes a diverging portion  30  that couples to the throat  28  and progressively increases in diameter in the direction of airflow. The diverging portion  30  may be coupled to the throat  28  by casting, screw threads, or by other known methods. As illustrated, the converging portion  26  may be longer in longitudinal length than the diverging portion  30 . 
     The venturi  18  is in communication with an airflow generator  32  that creates an airflow flowing from the first end  14 , through the inlet tube  12 , through the venturi  18 , and to the airflow generator  32 . The velocity of the generated airflow may range from 350 mph to supersonic. The airflow velocity will be greater in the venturi  18  than in the inlet tube  12 . The airflow generator  32  may be embodied as a fan, impeller, turbine, a hybrid of a turbine and fan, a pneumatic suction system, or other suitable device for generating a high speed airflow. 
     The airflow generator  32  is driven by a drive motor  34  that is generically represented and one of skill in the art will appreciate that any number of motors may be used, all of which are within the scope of the invention. The drive motor  34  couples to an axel  33  using known methods. The axel  33  engages the airflow generator  32  to power rotation. The horse power of a drive motor  34  will vary significantly, such as from 15 hp to 1000 hp, and depends on material to be treated, material flow rate, and airflow generator dimensions. Thus, this range is for illustrative purposes only as the system  10  can be scaled up or down. An upper scale system  10  may be used at a municipal waste processing facility whereas a smaller scale system  10  may be used to process sewage waste on board an ocean vessel. 
     The airflow generator  32  includes a plurality of radially extending blades that rotate to generate a high speed airflow. The airflow generator  32  is disposed within a housing  35  that includes a housing outlet  36  that provides an exit to incoming air. The housing  35  couples with the venturi  18  and has a housing input aperture (not shown) that allows communication between the venturi  18  and the interior of the housing  35 . The blades define radially extending flow passages through which air passes to a housing outlet  36  on its periphery to allow pulverized material to exit. One embodiment of an airflow generator  32  suitable for use with the present invention is discussed in further detail below in reference to  FIGS. 11 to 18 . 
     Referring to  FIG. 3 , a diagram is shown illustrating operation of the venturi  18  during a pulverization event. In operation, material  38  is introduced into the inlet tube  12  through any number of conveyance methods. The material  38  may be a solid or a semi-solid. The airflow generator  32  generates an air stream, ranging from 350 mph to supersonic, that flows through the inlet tube  12  and through the venturi  18 . In the venturi  18 , the airflow velocity substantially accelerates. The material  38  is propelled by the high speed airflow to the venturi  18 . The material  38  is smaller in diameter than the interior diameter of the inlet tube  12  and a gap exists between the inner surface of the inlet tube  12  and the material  38 . 
     As the material  38  enters the converging portion  26 , the gap becomes narrower and eventually the material  38  causes a substantial reduction in the area of the converging portion  26  through which air can flow. A recompression shock wave  40  trails rearwardly from the material and a bow shock wave  42  builds up ahead of the material  38 . Where the converging portion  26  merges with the throat  28  there is a standing shock wave  44 . The action of these shock waves  40 ,  42 ,  44  impacts the material  38  and results in pulverization and moisture extraction from the material. The pulverized material  45  continues through the venturi  18  and exits into the airflow generator  32 . 
     The material size reduction depends on the material to be pulverized and the dimensions of the system  10 . By increasing the velocity of the airflow, pulverization and particle size reduction increases with certain materials. Thus, the system  10  allows the user to vary desired particle dimensions by varying the velocity of the airflow. 
     The system  10  has particular application in pulverizing solid materials into a fine dust. The system  10  has further application in extracting moisture from semi-solid materials such as municipal waste, paper sludge, animal by-product waste, fruit pulp, and so forth. The system  10  may be used in a wide range of commercial and industrial applications. 
     Referring to  FIGS. 4 and 5 , an alternative embodiment of a system  100  of the present invention is shown for extracting moisture from materials. The system  100  may include a blender  102  for blending materials in a preprocessing stage. Raw material may include polymers that tend to lump the material into granules. The granules may be oversized and, due to the polymers, resist breaking down into a desired powder form. 
     The presence of polymers is typical with municipal waste as polymers are introduced during sewage treatment to bring the waste particles together. Waste is processed on a belt press resulting in a material that is mostly semi-solid. In some processes the material may be approximately 15 to 20 percent solid and the remainder moisture. 
     In the preprocessing stage, a drying enhancing agent is mixed with the raw material to break down the polymers and the granulization of the material. Non-polymerized products may be processed without the blending. Raw material is introduced into the blender  102  that blends the material with a certain amount of a drying enhancing agent. The drying enhancing agent may be selected from a wide range of enhancers such as aftapulgite, coal, lime, and the like. The drying enhancing agent may also be a pulverized and dried form of the raw material. The blender  102  mixes the material with the drying enhancing agent to produce an appropriate moisture content and granular size. 
     The raw material is transferred from the blender  102  to the hopper  22  in any one of a number of methods including use of a conveyance device  104  such as a belt conveyor, screw conveyor, extruder, or other motorized devices. In the illustrated embodiment, the conveyance device  104  is an inclined track that relies on gravity to deliver raw material to the hopper  22 . The conveyance device  104  is positioned below a flow control valve  106  located on the lower portion of the blender  102 . 
     In an alternative embodiment, the hopper  22  may be eliminated and material is delivered directly to the elongated opening  20  of the inlet tube  12 . The hopper  22  is only one device that may be used to facilitate delivery of material to the inlet tube  12 . Any number of other types of conveyance devices may be used as well as manual delivery. 
     One or more sensors  108  may monitor the flow rate of material passing from the blender  102  to the inlet tube  12 . A sensor  108  is in communication with a central processor  110  to regulate the flow rate. The sensor  108  may be disposed proximate to the conveyance device  104 , proximate to the hopper  22 , within the hopper  22 , or even between the hopper  22  and the elongated opening  20  to monitor the material flow rate. The central processor  110  is in communication with the flow control valve  106  to increase or decrease the flow rate as needed. Alternative methods for monitoring and controlling the flow rate may also be used including visual inspection and manual adjustment of the flow control valve  106 . 
     The hopper  22  receives the material and delivers the material to the elongated opening  20  of the inlet tube  12 . The elongated opening  20  may be equal to or less than 4″ wide and 5″ long to maintain an acceptable feed flow for certain applications. The length of inlet tube  12  from the elongated opening  20  to the venturi  18  may range from 24″ (610 mm) to 72″ (1830 mm) or more and depends on material to be processed and the flow rate. One of skill in the art will appreciate that the dimension are for illustrated purposes only as the system  10  is scalable. 
     The airflow pulls the material from the inlet tube  12  through the venturi  18 . In the illustrated embodiment, the first end  14  is configured as a flange to converge from a diameter greater than the inlet tube  12  to the diameter of the inlet tube. The flange configured first end  14  increases airflow volume into the inlet tube  12 . 
     Certain embodiments have the throat diameter of the venturi  18  ranging from approximately 1.5″ (38 mm) to approximately 6″ (152 mm). The throat diameter is scalable based on material flow volume and may exceed the previously stated range. The throat diameter of the venturi  18  and the inlet tube  12  are directly proportional. In one embodiment, the throat diameter is 2.75″ and operates with an inlet tube diameter of 5.5″ (139.33 mm). In an alternative embodiment, the throat diameter may be 2.25″ (57 mm) and operates properly with an inlet tube diameter of 4.50″ (114 mm). Thus, a 2 to I ratio ensures that raw feed material is captured in the incoming airflow. 
     In the illustrated embodiment, the diverging section  30  couples to the housing  35  and communicates directly with the housing  35 . The final diameter of the diverging section  30  is not necessarily the same as the inlet tube  12 . In an alternative embodiment, the diverging section  30  may couple to an intermediary component, such as a cylinder, tube, or pipe, prior to coupling with the housing  35 . 
     One or more flow valves  111  may be disposed on the diverging portion  30  and provide additional air volume into the interior of the housing  35  and the airflow generator  32 . The additional air volume increases the airflow generator  32  performance. In one embodiment, two flow valves  111  are disposed on the diverging portion  30 . The system  100  may be operated with the flow valves  111  partially or completely opened. If material begins to obstruct the venturi  18 , the flow valves  111  may be closed. This results in more airflow through the venturi  18  to provide additional force and drive material through the venturi  18  and the airflow generator  32 . The flow valves  111  are adjustable and are shown in electrical communication with the central processor  110  for control. Although manual operation of the flow valves  111  is within the scope of the invention, computer automation greatly facilitates the process. 
     The venturi  18  provides a point of impact between higher velocity shock waves and lower velocity shock waves. The shockwaves provide a pulverization and moisture extraction event within the venturi  18 . In operation, there are no visible signs of moisture on the interior of the venturi  18  or in the housing outlet  36 . The amount of moisture removed is substantial although a residual amount may remain. The pulverization event further reduces the size of materials. It has been experienced that certain materials having a diameter of 2″ (50 mm) entering the venturi  18  are reduced to a fine powder with a diameter of 20 um in one pulverization event. Size reduction depends on the material being processed and the number of pulverization events. Separating water from the material has numerous applications such as material dehydration and greatly reducing the number of pathogens. The possible applications for the present invention reach through a number of industries, the ramifications of which are only beginning to be realized. 
     The present invention has particular application in processing municipal waste. The preprocessing step of blending a drying enhancing agent provides a waste material that is readily processed by the system  100 . It is believed that the pulverizing and moisture extraction process greatly reduces the amount of illness causing pathogens in the waste material by rupturing their cell wall. A second source of pathogen reduction is moisture extraction which reduces the pathogens. Analytical data from treating municipal waste shows that the present invention eliminates the majority of total coliform, faecal coliform,  escherichia coli , and other pathogens. 
     The present invention has specific application in extracting moisture from fruit and vegetable products. In one application, the system  100  may be used to dehydrate fruit and vegetable products such as apples, oranges, carrots, nectarines, peaches, melons, tomatoes, and so forth. Extracted moisture, which is relatively sanitary, may be condensed and recaptured to provide a pure juice product. 
     In another application, the invention may be used to pulverize and extract water from certain agricultural products such as banana stalk, palm trees, sugar canes, rhubarb, and so forth. In pulverizing banana stalk fibers, the fibers are separated and moisture is extracted. Commercial applications exist in taking agricultural products from their natural state to a dehydrated state. Certain man-made products such as steel, rubber or plastics do not contain air as part of their natural composition and therefore cannot be pulverized. 
     The material, moisture, and air stream proceed through the airflow generator  32  and exit through the housing outlet  36 . The housing outlet  36  is coupled to an exhaust pipe  112  which delivers the material to a cyclone  114  for material and air separation. The diameter of the exhaust pipe  112  may range from approximately 4″ (100 mm) to 7″ (177 mm). It may be necessary to exceed this given range for certain materials such as attapulgite or coal where a 8″ (203 mm) exhaust pipe  112  is appropriate. Although referred to as a pipe, one of skill in the art will appreciate that the exhaust pipe  112  may have a cross-section of various shapes, i.e. rectangular, octagonal, etc. and various diameters and still be within the scope of the invention. 
     The exhaust pipe  112  may have a length of approximately 12 feet to 16 feet. The diameter size of the exhaust pipe  112  impacts the amount of drying that further occurs. High air volume is required for further drying of materials. In the exhaust pipe  112 , the faster moving air in the exhaust pipe  112  passes the material and removes moisture remaining on the material. The air and vapor travel to a cyclone  114  where air and vapor are separated from the solid material. 
     A pulverization event generates heat that assists in drying the material. In addition to pulverization, rotation of the airflow generator  32  generates heat. The dimensions between the housing  35  and the airflow generator  32  are such that during rotation the friction generates heat. The heat exits through the housing outlet  36  and exhaust pipe  112  and further dehydrates the material as the material travels to the cyclone  114 . The generated heat may also be sufficient to partially sterilize the material in certain applications. 
     The diameter of the housing outlet  36  may be increased or decreased to adjust the resistance and the amount of heat traveling through the housing outlet  36  and exhaust pipe  112 . The diameter of the exhaust pipe  112  and the housing outlet  36  effects the removal of moisture on pulverized material. Adjusting the outlet diameter is further discussed below. 
     The pulverization and moisture extraction increases as the airflow generated by the airflow generator  32  increases. If airflow is increased or decreased, the diameter of the exhaust pipe  112  and housing outlet  36  may be decreased to provide the same material dehydration. Thus, the airflow and diameters may be adjusted relative to one another to achieve the desired dehydration. 
     Heavier materials with less water, such as rock materials, require less moisture extraction. With such materials, the housing outlet  36  and exhaust pipe  112  diameters may be increased as less drying is required. Consequently, with wetter materials, the housing outlet  36  and the exhaust pipe  112  diameters may be decreased to increase the amount of air and heat to achieve the proper dehydration of the material. 
     The angle of inclination of the exhaust pipe  112  relative to the longitudinal axis of the venturi  18  and airflow generator  32  also effects dehydration performance. The exhaust pipe angle V may be approximately 25 degrees to approximately 90 degrees in order to enhance moisture extraction. Material traveling upward is held back by gravity whereas air is less restricted by gravity. This allows the air to move faster than the material and increase moisture removal. The angle V may be adjusted to increase or decrease the effect on moisture extraction. The exhaust pipe  112  may be straight as illustrated or curved as shown in phantom. 
     The cyclone  114  is a well known apparatus for separating particles from an airflow. The cyclone  114  typically includes a settling chamber in the form of a vertical cylinder  116 . Cyclones can be embodied with a tangential inlet, axial inlet, peripheral discharge, or an axial discharge. The airflow and particles enter the cylinder  116  through an inlet  118  and spin in a vortex as the airflow proceeds down the cylinder  116 . A cone section  120  causes the vortex diameter to decrease until the gas reverses on itself and spins up the center to an outlet  122 . Particles are centrifuged toward the interior wall and collected by inertial impingement. The collected particles flow down in a gas boundary layer to a cone apex  124  where it is discharged through an air lock  126  and into a collection hopper  128 . 
     In certain applications, the system  100  may further include a condenser  130  to receive the airflow from the cyclone  114 . The condenser  130  condenses the vapor in the airflow into a liquid which is then deposited in a tank  132 . An outlet  134  couples to the condenser  130  and provides an exit for air. As can be appreciated, the condenser  130  has particular application with food processing. In an alternative embodiment, the condenser  130  is embodied as an alternative treatment device such as a charcoal filter or the like. As can be appreciated, condensation or filtering will depend on the material and application. The outlet  134  may include or couple to a filter (not shown) to filter residue, particles, vapor, etc. from the outputted air. The filter may be sufficient to comply with government regulatory standards to provide a negligible impact on the environment. 
     Passing material through the system  100  multiple times will further dehydrate material and will further reduce particle size. In municipal waste applications, multiple cycles through the system  100  may be required to achieve the desired dehydration results. The present invention contemplates the use of multiple systems  100  in series to provide multiple venturis  18  and multiple pulverization events. Thus, a single cycle through multiple systems  100  in series achieves the desired results. Alternatively, material may be processed and reprocessed by the same system  100  until the desired particle size and dryness is achieved. 
     In one implementation, the resulting product issuing from a system  100  is analyzed to determine the size of the powder granules and/or the moisture percentage. If the product fails to meet a threshold value for size and/or water percentage the product is directed through one or more cycles until the product meets the desired parameters. 
     The present invention allows homogenization of different materials. In operation different materials enter the inlet tube  12  together, are processed through the venturi  18 , and undergo pulverization. The resulting product is blended and homogenized as well as being dehydrated and reduced in size. 
     A particular application of the present invention involves the homogenization of landfill product with coal. After pulverization and water extraction, the combined and homogenized waste and coal product is used in a coal burner to achieve optimum burning rates for creating steam in an electrical generation plant. The waste is used for energy production rather than for routine disposal. 
     If desired, the material may be mixed in the blender  102  prior to pulverization or at an intermediate stage between pulverization events. Mixing materials may enhance homogenization with certain materials. If desired, the material may be mixed in the blender  102  prior to pulverization or at an intermediate stage between pulverization events. 
     Materials blended in a preprocessing stage may be cycled through multiple pulverizing stages to provide the desired homogenization. A first material may be processed through multiple pulverizing stages and then homogenized with a second material. Between pulverizing stages the second material may be blended with the processed material in a preprocessing stage. The first and second materials are then passed through one or more pulverizing stages to produce a homogenized, final product. 
     As an additional example, a first material may cycle through three pulverizing stages. After the third pulverizing stage, a second material may be blended together in a blender  102 . Before mixing, the second material may have passed through a venturi  18  for pulverization and reduction to a desired particle size. The first and second materials may then pass together through one or more additional pulverizing stages to provide the desired moisture content, size, and homogenization for industrial use. 
     Referring to  FIG. 6 , a perspective view is shown of a housing  200  that includes a housing outlet  202 . The housing  200  encompasses the operational components of an airflow generator  32 . The housing  200  is shown with a cut-away section to illustrate the airflow generator  32  within. In order to provide variance in the output flow, a restrictor  204  may be introduced into the housing outlet  202 . A restrictor  204  increases the resistance to the airflow and also increases heat. Varying the amount of resistance and airflow is dependent on the material to be processed. 
     A restrictor  204  includes a neck  206  to nest within the housing outlet  202  and a restrictor aperture  208 . The restrictor aperture  208  has a cross-section less than that of the housing outlet  202 . A restrictor aperture  208  may be rectangular, circular, or have another suitable shape. The neck  206  provides a converging flow path from a cross-section approximating that of the outlet  202  to the final cross-section of the restrictor aperture  208 . A number of restrictors  204  with varying aperture sizes may be available to manipulate the output flow and thereby tune the system  100  to suit the material. 
     Referring to  FIG. 7 , a cross-sectional view of an airflow generator  32  within a housing  200  is shown. The airflow generator  32  may not be coaxially aligned within the housing  200 . In one implementation, the airflow generator  32  includes a diverter plate  250  that has a cutting edge  252  near the airflow generator  32 . The cutting edge  252  of the diverter plate  250  directs pulverized material into the housing outlet  202 . The diverter plate  250  is coupled to the interior of the housing  200  and may be coupled to the interior of the housing outlet  202 . 
     The diverter plate  250  prevents pulverized material from further rotation within the housing  200 . As such, the diverter plate  250  serves as the first separation of pulverized material from air that continues to rotate within the housing  200 . Subsequent separation of pulverized material from air is performed by the cyclone  114 . If pulverized materials continue to rotate within the housing  200  the pulverized materials may build up and eventually obstruct the airflow generator  32 . The cutting edge  252  varies the airflow volume proceeding through the housing  200 . 
     The separation of the cutting edge  252  of the diverter plate  250  from the airflow generator  32  may range from about 20 thousandths of an inch to 100 thousandths of an inch. The position of the diverter plate  250  may also be adjustable to increase or decrease the separation from the airflow generator  32 . Adjustment may be required depending on the materials being processed or to manipulate airflow volume. Adjustment may be controlled by the central processor  110  which communicates with an electromechanical or pneumatic device for moving the diverter plate  250 . The cutting edge  252  has a bevel that accommodates the shape of the airflow generator  32 . 
     Referring to  FIG. 8 , a cross-sectional view of a venturi  18  with an accompanying throat resizer  300  is shown. The throat resizer  300  is a removable component that, when inserted, nests within the throat  28 . The throat resizer  300  alters the effective diameter of the throat  28  and increases the air velocity. Variance of the throat diameter is required depending on the material and the desired dehydration and particle reduction. Thus, although the airflow generator  32  may vary the airflow, it is further desirable to manipulate throat diameter of venturi  18 . 
     The throat  28  may be configured with a ledge  302  upon which a collar  304  of the throat resizer  300  nests. A crown member  306  is coupled to the collar  304  and conforms to the interior surface of the converging portion  26 . The throat resizer  300  includes a sleeve  308  that conforms to the interior surface of the throat  28  and extends within a major portion of the venturi throat length to resize the venturi  18 . 
     Referring to  FIG. 9 , an alternative embodiment of a system  400  is shown that incorporates two pulverizing stages  402 ,  404 . Each time material passes through a venturi  18 , pulverization occurs, moisture is extracted, and particle reduction occurs. As discussed previously, this process may be repeatedly performed with a single venturi  18  or with multiple venturis  18  in series until the desired amount of water is extracted and product size is achieved. This process may be continued until nearly 100 percent water extraction is achieved. 
     Although two pulverizing stages are shown with the system  400 , one of skill in the art will appreciate that a system may include three, four, five, or more stages. The first pulverizing stage  402  is similar to that previously described in reference to  FIGS. 4 and 5 . The first pulverizing stage  402  includes a hopper  22 , blender  102 , conveyance device  104 , flow control valve  106 , venturi  18 , housing  35  (with an airflow generator  32  within), and an exhaust pipe  112 . The system  400  may further include a flow control valve  405  in the exhaust pipe  112  to regulate airflow within. 
     As in the previous embodiments, the exhaust pipe  112  couples to a cyclone  114  to separate the processed product from the air. The system  400  may further include a second cyclone  406  to receive air from the outlet  122  of the first cyclone  114 . The second cyclone  406  further separates air from residual particles and delivers the purified air to a condenser  130 . A first tank  132  is in communication with the second cyclone  406  to receive condensed liquid from the condenser  130 . An outlet  134  provides an exit for air passing from the condenser  130  and the second cyclone  406 . A residual hopper  408  is positioned to receive residual particles from the second cyclone  406 . 
     Particles separated by the first cyclone  114  are delivered to a hopper  410  using any number of conventional techniques including gravity. Although not shown, particles from both the first and second cyclones  114 ,  406  may be delivered to the hopper  410 . The hopper  410  receives the particles that then undergo the second pulverizing stage  404 . The hopper  410  delivers the particles to a second inlet tube  412  that is coupled to a second venturi  414  as with the first pulverizing stage  402 . 
     One or more flow valves  416  are located on the second venturi  414  and are in electrical communication with the central processor  110 . The flow valves  416  function similar to those previously described and referenced as  111 . 
     The second venturi  414  communicates with a second airflow generator (not shown) in a housing  418 . The second airflow generator generates a high speed airflow through the venturi  414 . The second housing  418  couples to a second exhaust pipe  420  that delivers air and processed material to a third cyclone  422 . The second exhaust pipe  420  is inclined at an angle of approximately 25 degrees to approximately 90 degrees relative to the longitudinal axis of the second venturi  414 . A second flow control valve  424  is within the second exhaust pipe  420  to regulate airflow within. As with the first flow control valve  404 , the second flow control valve  424  is in electrical communication with the central processor  110  for regulation. 
     The third cyclone  422  separates the particles from the air and delivers a product that is delivered to another conveyance device  425 . A fourth cyclone  426  receives air from the third cyclone  422  and further purifies the air and removes residual particles. Residual particles from the fourth cyclone  426  are deposited in a residual hopper  428 . The fourth cyclone  426  delivers air to a second condenser  430  where vapor is condensed into a liquid and received by a second tank  432 . An outlet  434  couples to the second condenser  430  to allow air to exit. 
     The system  400  further includes a heat generator  436  to provide heat through the inlet tubes  12 ,  412  and the venturis  18 ,  414  and assist in drying materials. The addition of heat is not required for water extraction and is merely used to further increase the drying potential of the present invention. The heat generator  436  may communicate with the hoppers  22 ,  438  or with the inlet tubes  12 ,  412 . A heat generator  436  may also be used in a similar manner in the embodiments illustrated in  FIGS. 1 ,  2 ,  4 , and  5 . 
     In  FIG. 9 , the heat generator  436  is in communication with a first heat control valve  440  to deliver heat to the first hopper  22 . The first heat control valve  440  is in electrical communication with the central processor  110  to regulate the heat delivery. Alternatively, the heat control valve  440  may be operated manually. The heat generator  436  is further in communication with a second heat control valve  442  that regulates heat flow to hopper  438 . Heating material during the second pulverizing stage  404  may be desired depending on the material or the application. If heating is desired, the hopper  438  receives particles from the first cyclone  114 . Otherwise, the material may pass to the hopper  410  as illustrated in  FIG. 9 . 
     One of skill in the art will appreciate that the system  400  may be varied to include or remove several components and still be well within the scope of the invention. The system  400  may include one or more pulverizing stages for further dehydration and particle reduction. The conveyance device  425  may feed back into the blender  102  or the hopper  22  for further cycling of product through the pulverizing stages  402 ,  404 . The second and fourth cyclones  406 ,  426  provide further purification of air but the added cost may not be justified for certain applications. In certain applications the condensers  130 ,  430  may be removed or another type of treatment apparatus, such as a filter, be used. Flow control valves may also be introduced or removed throughout the system  400  as warranted and as based on design constraints. Thus, the system  400  should be considered as illustrative of one implementation of the present invention and should not be deemed to limit variations thereto. 
     Referring to  FIG. 10  an alternative embodiment of a pulverization and moisture extraction system  450  is shown. The system  450  is similar to that of  FIG. 4  and S and further includes a second cyclone  406  in communication with the first cyclone  114 , a residual hopper  408  to collect particles from the second cyclone  406 , a condenser  130  in communication with the second cyclone  406 , a tank  132  in communication with the condenser  130 , and an outlet  134  coupled to the condenser  130 . The system  4 S 0  further includes a diverter valve  452  coupled to the first cyclone  114 . 
     The diverter valve  452  directs particles received from the first cyclone  114  to a first outlet  454  or a second outlet  456 . The first outlet  454  is coupled to a collector  458  such as a bag, hopper, tank, or the like. The second outlet  456  is coupled to a recycling tube  460  to introduce the pulverized material through the system  450  again. The recycling tube  460  is coupled at its opposing end to the first end  14 . Alternatively, the recycling tube  460  may direct pulverize material into the hopper  22  or directly into the elongated opening  20 . 
     In operation, material is pulverized as it passes through the system  450  and is redirected, by control of the diverter valve  452 , to pass through the system  450  again for another pulverization event. This may be repeated as desired until a final product results which is then directed by the diverter valve  452  into the collector  458 . 
     Referring to  FIG. 11 , an embodiment of an airflow generator  500  suitable for the present invention is shown. Various metals are suitable for the airflow generator, depending on the material to be processed. For abrasive material, a harder alloy steel may be used. As can be appreciated by one of skill in the art, the material selected is a balance between strength and anticipated wear. Casting of the airflow generator  500  is advantageous as fabrication via welding creates inconsistent surfaces and heat effected areas due to heat effected zones. The cast airflow generator  500  may have a variable material thickness to resist rapid structural impacts and accelerated wear resulting from processing various materials. The section thickness and resulting total weight of the airflow generator  500  is directly proportional to the air volume and material flow rate that is to be processed. 
     The airflow generator  500  is received within a housing such as that illustrated in  FIG. 6 . The housing  200  at least partially encircles the airflow generator  500  and preferably completely encircles the airflow generator  500  so that the only egress is the housing outlet  36 . The airflow generator  500  may have a close clearance to the housing  200  to generate additional friction and heat. The heat is desired to assist in further drying materials passing through the airflow generator  500  and into the exhaust pipe  112 . 
     The airflow generator  500  includes a front plate  502  with a concentrically disposed input aperture  504  to receive incoming materials. The diameter of the input aperture  504  is variable depending on the processed material size and anticipated air volume. A back plate  506  parallels the front plate  502  and includes a concentrically disposed axel aperture  508 . As the name suggests, the axel aperture  508  receives and engages an axel or spindle to power rotation. Alternative airflow generators  500  may be used with the present invention and include generators with a single back plate coupled to blades or generators with radially extending blades alone. 
     The back plate  506  may further include bolt apertures  509  that are disposed concentrically around the axel aperture  508 . The bolt apertures  509  each receive a corresponding axel bolt (not shown) that are each coupled to an axel. The axel bolts are secured to back plate  506  by nuts or other conventional devices. 
     Although the thickness of the front and back plates  502 ,  506  may vary considerably, in one design the back plate  506  is approximately ⅜″ (8 mm) and the front plate  502  is 3/16″ (5 mm). Specific measurements are given as examples and should not be deemed limiting of the present invention. 
     A plurality of blades  510  are disposed between the front and back plates  502 ,  506  and are coupled to both plates  502 ,  506 . As can be appreciated, the number of blades  510  may vary and depends, in part, on the material to be processed. The thickness of the blades  510  may also vary depending on the material to be processed. 
     In one embodiment, the blades  510  extend through the front and back plates  502 ,  506  to form blade fins  511  on the exterior face of the front and back plates  502 ,  506 . The blade fins  511  may extend approximately ½″ (12 mm) from either the front or back plates  502 ,  506 . The blade fins  511  generate a cushion of air between the airflow generator  500  and the interior of the housing  200 . The blade fins  511  further act to clean out materials that may enter between the housing  500  and the airflow generator  200 . 
     Referring to  FIG. 12 , a cross-sectional view of the axel aperture  508  is shown. The axel aperture  508  receives an axel, shaft, spindle, or other member to rotate the airflow generator  500 . The bolt apertures  509  each receive an axel bolt to secure the back plate  506 . In this embodiment, an axel transitions from a first diameter, with axel bolts extending, to a second diameter suitable for insertion into the axel aperture  508 . The bolt apertures  509  may each provide a well  513  to receive a nut that engages an axel bolt. 
     Referring to  FIG. 13 , a plan view of the interior of the airflow generator  500  is shown with a single blade  510 . The single blade  510  is shown to illustrate the unique features of blades  510  incorporated within the airflow generator  500 . The remaining blades  510  are similarly embodied. 
     The blade  510  extends from a tail edge  512  at the perimeter  513  of the back and front plates  502 ,  506  to a leading edge  514  adjacent the axel aperture  508 . The blade  510  includes a wedge portion  516  adjacent the tail edge  512 . The wedge portion  516  has a thicker cross-section to increase pressure and airflow volume. The wedge portion  516  provides increased resistance to wear which is advantageous with some materials. 
     Referring to  FIG. 14A , a plan view illustrating the wedge portion  516  in greater detail is shown. The shape of the wedge portion  516  affects airflow volume, airflow velocity, and material flow rate through the airflow generator  500 . The wedge portion  516  may be altered in the circumferential and longitudinal direction to alter airflow volume, airflow velocity, and material flow rate. Casting techniques advantageously allow variance in three dimensions and allows any number of circumferential and longitudinal profiles in the wedge portion  516 . 
     The increased thickness of the wedge portion  516  enhances the life of the airflow generator  500  as this is where the blade  510  typically experiences the most wear. The material used and the hardness of the wedge portion  516  may also differ from the remainder of the blade  510 . 
     Referring to  FIG. 14B , an alternative embodiment of a wedge portion  518  is shown which includes a replaceable wear tip  520 . With the airflow generator  500  rotating in a clockwise direction, the replaceable wear tip  520  is subject to the most material contact. Although thickened to increase wear resistance, the wedge portion  518  is subject to more wear than other components of the airflow generator  500  and may wear out sooner. By replacing the replaceable wear tip  520 , replacement of the entire airflow generator  500  is deferred. The replaceable wear tip  520  is coupled to the remainder of the wedge portion  518  through any known fastening device including a securing nut and bolt assembly S 22 . The replaceable wear tip  520  may be a material harder than the remainder of the blade  510 . The replaceable wear tip  520  may also be replaced with a replaceable wear tip  520  having a different circumferential and longitudinal profile. In yet another embodiment, the entire wedge portion  518  is replaceable. 
     Referring to  FIG. 15A , a perspective view of the airflow generator  500  is shown illustrating the wedge portion  516  coupled to the front and back plates  502 ,  506 . The blade fins  511  are further shown extending from the exterior surface of the front and back plates  502 ,  506 . As shown, the wedge portion  516  is substantially thicker than the corresponding blade fins  511 . The blade fins  511  are not subject to the same wear as the wedge portion  516  and are not as thick. 
     Referring to  FIG. 15B  a perspective view of the airflow generator  500  is shown with an alternative embodiment of the wedge portion  516 . The wedge portion S 16  increases its thickness and its circumferential profile as it extends in the longitudinal direction from the front plate S 02  to the back plate  506 . The wedge portion  516  also increases in thickness as it extends radially towards the perimeter. 
     Pulverized material entering into the airflow generator  500  has a tendency to accumulate proximate to the back plate  506 . The longitudinally increasing thickness encourages pulverized material to remain centered between the front and back plates  502 ,  506  rather than accumulating along the back plate  506 . Casting techniques enable production of such a wedge portion  516  as three dimensional variation is possible. The replaceable wear tip  520  may include and define the longitudinally increasing thickness. If another wedge portion  516  shape is desired another replaceable wear tip  520  without a longitudinally increasing thickness or a more pronounced longitudinally increasing thickness may be used. Thus, pulverized material flow direction may be manipulated longitudinally by using wedge portions  516  of different circumferential and longitudinal configurations. 
     Referring again to  FIG. 13 , the blade  510  transitions from a position perpendicular to the back plate  506  to an angled position. The blade  510  transitions as it proceeds from the wedge portion  516  to a location prior to the leading edge  514 . The angled position causes the blade  510  to pitch into the direction of the airflow. 
     In the illustrated embodiment, a tail portion  524  of the blade  510 , including the wedge portion  516 , extends perpendicular from the back plate  506 . The tail portion  524  may be approximately one fourth to one half of the blade  510  as the blade  510  extends from the tail edge  512  to the leading edge  514 . A leading portion  526  is the remaining amount of the blade  510  from the tail portion  524  to the leading edge  514 . The illustrated leading portion  526  has an angled transition from a perpendicular position relative to the back plate  506  to an angled position. 
     The angled position has an angle that is referred to herein as the attack angle as it allows the leading edge  514  to cut into the incoming airflow. In  FIG. 13 , the final attack angle of the blade  510  at the leading edge  514  is approximately 25 degrees. The transition from a perpendicular position to an angled position may extend over the entire blade  510  or any portion thereof. The attack angle may be selected from a broad range of angles based on anticipated airflow velocity, material flow rate, and material. The angled position may have a range of approximately 20 to 60 degrees. 
     Alternatively, the blade  510  may remain perpendicular along its entire length. The blade  510  may also have an attack angle along its entire length. Although extending along the entire length, the attack angle may still vary as the blade  510  extends from the tail edge  512  to the leading edge  514 . 
     Referring to  FIG. 16 , a profile view of the leading edge  514  is shown. Conventionally, an edge may be relatively straight and proceed on an angle relative to the back plate  506 . In one embodiment of the present invention, the leading edge  514  proceeds from the back plate  506  with an outwardly curving portion  528  and then transitions into an inward curve  530 . The outwardly curving portion  528  assists in capturing air traveling into the input aperture  504  of the airflow generator  500 . The leading edge  514  so profiled is able to cut into air and improve the efficiency of the airflow generator  500 . 
     Referring to  FIG. 17  a cross section of the leading edge  514  taken along section  17 - 17  is shown. The leading edge  514  has an oval shaped cross-section that assists in slicing into incoming airflow. 
     Referring to  FIG. 18 , a perspective view of the airflow generator  500  is shown without the front plate  502  to illustrate the blades  510 . The illustrated embodiment includes nine blades  510  although the number is variable. Each blade  510  includes a wedge portion  516  for added resistance to wear and to increase pressure and airflow. Each blade  510  further transitions from a perpendicular position to an attack angle. The attack angle inclines towards the clockwise position that corresponds to the anticipated rotation of the airflow generator  500 . One of skill in the art will appreciate that the airflow generator  500  may be operated in the counter-clockwise position and the blades  510  would be inclined in that direction. 
     In operation, the rotating blades  510  generate a high speed airflow ranging from 350 mph or greater and directs air and pulverized material into the input aperture  504 . The leading edges  514  of the blades  510  cut into the air and pulverized material and direct both the air and pulverized material into flow paths  532  defined by the blades  510  and extending from the input aperture  504  to the perimeter  513  of the front and back plates  502 ,  506 . The flow paths  532  would have a maximum flow rate for materials passing through. The wedge portions  516  push the air and pulverized material to the housing outlet  202  that is located within the housing  200 . Although the airflow generator  500  provides unique features, one of skill in the art will appreciate that any number of devices may be used and are included within the scope of the invention. 
     The present invention provides a pulverizing and dehydrating system that can accommodate various materials and various flow rates. The systems described herein are scalable for the different applications and different sized materials and any specific component dimensions are given only as examples. Thus, a system may be sized as a bench-top model or as a large industrial-sized unit. 
     The systems  10 ,  100 , 400 , 450  disclosed herein may be mounted to a ground surface and larger scale embodiments are more likely to be so constructed. Alternatively, a system may be mounted within or on a vehicle such as a truck, trailer, rail car, boat, barge, and so forth. Any vehicle that provides a sufficient planar footprint may be used. Having a mobile system is advantageous in certain applications such as agricultural harvesting, remote site treatments, demonstrations, and so forth. 
     Referring to a  FIG. 19 , a block diagram representing a mobile system  600  is shown. The system  600  includes components previously discussed such as the inlet tube  12 , venturi  18 , airflow generator  32 , housing  35 , motor  34 , exhaust pipe  112 , and first and second cyclones  116 ,  406 . The system  600  may include additional elements such as the blender  102 , central processor  110 , condenser  130 , and so forth. Systems with a plurality of pulverization stages may be mounted on a vehicle in similar manner. Thus, the illustrated system  600  should be considered for exemplary purposes only. 
     The system  600  includes a vehicle generically represented as  602  and providing a sufficient footprint to support the assembled components. The system  600  further includes a plurality of supports  604  that couple to the vehicle  602  and support any number of assembled components. The system  600  may further include a housing  606  that encompasses components of the system. The housing  606  protects the components and dampens noise during operation. 
     One or more components of the system  600  may be removable to facilitate transportation. For example, the first and second cyclones  116 ,  406  may extend out of the housing  606  and need to be moved during transportation. The cyclones  116 ,  406  may be removed entirely or partially dissembled prior to transportation. Similarly a blender  102  may be removable for transportation. The necessity of removing components is based on the size of the system  600 , vehicle  602 , and other design constraints. 
     The housing  606  may accommodate a control room for a user to operate the system  600 . The housing  606  may include windows for viewing the components and access for viewing, operation, repair, and inserting material to be processed. The system  600  may have any number of configurations based on convenience, application, and other design considerations. Thus, the illustrated system  600  should be considered as only being an example, and not deemed limiting of the present invention. 
     It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the present invention should, therefore, be determined only by the following claims.