Patent Abstract:
An aggregate washing and classification system incorporates into a water-filled receptacle a sand classifier and one or more rotating augers. The augers are wrapped with screens or perforated walls that are fixed relative to the augers. The size of the perforations may be chosen to selectively sift particular sizes of gravel and rock, and if the perforations increase in size along the length of the augers, either continuously or discontinuously, the material which passes through the perforations will likewise increase in size with greater travel through the auger passageway. Consequently, a set of rock bins may be provided adjacent to the auger outlet, for collecting various sizes of larger aggregate, such as washed rocks. Sand will typically be permitted to pass through the screen perforations near the aggregate inlet. Once outside of the auger and screens, the sand will drop directly into a sand classifier, which is conveniently located directly below the augers and adjacent to the material inlet. Fresh water is pumped into the bottoms of the rock bins, and flows counter to the aggregate passing through the augers. The counter-flow keeps the rock bins clean, and the flow of water adjacent and counter to the material inlet is used to extract and discharge low-density matter from the aggregate inlet. The entire system is desirably incorporated into a single land vehicle for transport to aggregate sources, such as gravel pits and the like, where the finest grades of aggregate may be rapidly prepared.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. provisional patent application Ser. No. 60/685,632 filed May 26, 2005 and of common title and inventorship, the contents which are incorporated herein by reference in entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention pertains to classifying, separating, and sorting solids generally, and more specifically in one manifestation to a device using aqueous suspension, sifting, and stratifying to wash and classify aggregate. 
     2. Description of the Related Art 
     Cleaning and classifying aggregate matter is an old technology with many applications in modern society. A primary application is in the production of suitable aggregate for the fabrication of high-quality concrete products. As is known in the concrete industry, many characteristics of concrete can be greatly enhanced through the addition of appropriate aggregate materials. The aggregate additives are incorporated in relative quantities based upon particular size ranges, so that a typical mix will include some combination of both sand and one or more sizes of larger stones. Through appropriate size and even shape selection, the concrete can be designed to have the best characteristics for a given application. 
     However, in order for the aggregate additives to provide the intended benefits without undesirable disadvantages, the aggregate needs to be both clean and properly classified into size ranges. Humus, clay, wood and paper, and even softer and lower density rock such as shale can very adversely affect the performance of a concrete product. These undesirable materials can deleteriously alter such characteristics as compression strength, spalling, and wear or abrasion resistance, chemical resistance, and other characteristics. Consequently, it is very desirable to remove such materials prior to the aggregate matter being incorporated into a concrete mix. 
     There are many additional applications for washed and classified aggregate, including but not limited to road, building and other construction, landscaping, mining, sand blasting and casting, and even filtration. The different applications may have more or less stringent requirements for both size ranges and cleanliness of product, which may often vary not only by the application, but also by a given job requirement. Consequently, while aggregate for concrete mixes are discussed for exemplary purposes herein, it will be understood that other applications are contemplated as well. 
     In order to produce suitable aggregate, many facilities depend entirely upon large agitated screens. These screens will typically be loaded with a quantity of aggregate mix, and then shaken or vibrated relatively violently. Matter which is smaller than the screen opening will pass through the screen, where it will typically be caught upon the next screen, which will normally have an even smaller opening size. With sufficient agitation, all of the smaller particles will pass through the screen, while the larger particles will be blocked by the screen. By cascading several screens, it is possible to classify the aggregate mix into particular rock and gravel sizes. Unfortunately, this approach generates a great deal of dust during the agitation of the screens, and so water sprays are often used to keep the dust down. In some instances, the water spray may also assist with the removal of silt or humus, though quite frequently it will be desirable to keep the mist fine and light enough to only serve as dust control. More water may actually interfere with the screening, and may permit clay, for exemplary purposes and not limited thereto, to stick directly to desirable rock. Consequently, without a full washing, the spray can interfere with the separating process. As a result, the classified aggregate produced by this method tends to be relatively dirty, and may require further washing for the more demanding applications. 
     The use of a water mist also limits the environment where the apparatus may be applicable. As residents of northern climates will recognize, it is not practical to spray a mist during colder, sub-freezing weather. Consequently, the mist dust control is dependent upon warmer weather, undesirably limiting the screening and classifying to the warmer seasons. Further, the mist will rapidly evaporate from the surfaces of the aggregate. This evaporation may lead to very undesirable losses in the very arid climates, again limiting the application and generally preventing misting in arid climates or during times of drought. Since sensitivity of machinery to weather is almost always disadvantageous, causing interruptions in work projects and disruption of schedules, it is consequently desirable to reduce the sensitivity of the apparatus to climate. 
     Because the screens rely upon lifting and dropping of the aggregate upon the screen, the process requires substantial machinery to have high throughput of matter. In other words, it takes a great deal of energy to repetitively lift and drop the aggregate, and that in turn means large motors and strong frames and supports. Moreover, the extra energy is usually dissipated in the screens, resulting in substantial erosion of the screens and frequent replacement. 
     Yet another drawback of the agitated screen is the inability of the process to separate out the hardness or density of the materials being sifted. In other words, it is difficult to separate wood and sticks from rocks, and also low-density rocks such as shale from higher density harder rocks. Consequently, when using a sifting process, a separate and additional machine and process is required to further clean and separate undesirable matter. 
     SUMMARY OF THE INVENTION 
     Exemplary embodiments of the present invention solve inadequacies of the prior art by providing a rotary screen with counter-flowing water. The water may be either fresh, or filtered on site using a filter, sedimentation pond or other suitable means. With appropriate design, a sand classifier may be integrated directly into the apparatus, and cooperate with the rotary screen and counter-flowing water. The design may be either fixed or mobile, and when mobile provided with a wheel-set such as a trailer, or be provided as a fully functional vehicle. 
     In a first manifestation, the invention is a rotary aggregate washing and classification system. The system comprises in combination a material inlet for receiving material therein, a reservoir containing a fluid therein, at least one screen mesh, and a sand classifier within the reservoir. The at least one screen mesh has at least one screen opening size, is coupled to the material inlet suitably to receive material therefrom, and passes at least partially through the reservoir, thereby forming a passage for material smaller than the at least one screen opening size to pass through while larger material is prevented from passing through. The at least one screen mesh is operative to separate larger material from smaller material. The sand classifier is located within the reservoir and receives smaller material after the smaller material passes through the at least one screen mesh and is cooperative with a flow within the fluid and with smaller material, to grade smaller material into at least two coarseness increments. 
     In a second manifestation, the invention is an aggregate washing and classification system. In the system, a material inlet receives material. A reservoir contains a fluid. At least one screen mesh has at least one screen opening size, and is coupled to the material inlet suitably to receive material therefrom. The screen mesh passes at least partially through the reservoir, and thereby forms a passage for material smaller than the at least one screen opening size to pass through while material larger than the at least one screen opening size is prevented from passing through, whereby the at least one screen mesh is operative to separate larger material from smaller material. At least one rock bin has a top which receives graded material that has passed through the at least one screen mesh, a bottom, a fluid inlet distal from the rock bin top, a fluid discharge adjacent the rock bin top, and a means to discharge graded material from the rock bin to a location external to the rotary aggregate washing and classification system. The rock bin at least temporarily stores rocks therein and also conducts fluid received at the fluid inlet to the rock bin top for discharge therefrom. 
     In a third manifestation, the invention is a method of washing and sorting aggregated materials to separate useful rocks and sands from debris. According to the method, aggregated materials are introduced through a passageway inlet into a passageway at least partially defined by a perforated wall and at least partially flooded with a fluid contained in a receptacle. A first fraction of aggregated materials is separated from a second fraction by passing the first fraction through the perforated wall, while retaining the second fraction within the passageway. The second fraction of aggregate materials is moved within the passageway to a passageway discharge distal to the passageway inlet. The first fraction of aggregate materials is transferred into a temporary storage bin. The temporary storage bin is streamed with a relatively purer fluid than passageway fluid. The relatively purer fluid stream is then conducted from temporary storage bin to passageway discharge and into the passageway, thereby washing impurities from the first fraction of aggregate materials into the passageway fluid. 
     OBJECTS OF THE INVENTION 
     A first object of the invention is to provide an efficient and effective method and apparatus for washing and classifying an aggregate. A second object of the invention is to remove as much undesirable matter from an aggregate mix as reasonably possible. Another object of the present invention is to quickly and efficiently classify the aggregate mix into appropriate size ranges. An ancillary object is to permit release of relatively precise proportions of the various size ranges, to facilitate the formation of an aggregate mix to specification. A further object of the invention is to perform the desired washing and classification with high throughput, while not requiring as large a machine as was heretofore needed and while keeping wear to a minimum. An additional object of the invention is to reduce sensitivity to the environment, to permit the machine to operate at lower temperatures and in water-scarce areas. Yet another object of the present invention is to enable the apparatus for washing and classifying to be portable without significant disassembly or labor, such that the apparatus may readily be transported as a trailer or load upon a vehicle from location to location. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing and other objects, advantages, and novel features of the present invention can be understood and appreciated by reference to the following detailed description of the invention, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  illustrates a first preferred embodiment rotary aggregate washing and classification system designed in accord with the teachings of the present invention from side sectional view. 
         FIG. 2  illustrates a second preferred embodiment rotary aggregate washing and classification system designed in accord with the teachings of the present invention from side sectional view. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Manifested in the preferred embodiment of the invention illustrated in  FIG. 1 , the present invention provides a rotary aggregate washing and classification system  10  which is operative to receive, wash and separate aggregate into useful components and waste. Aggregate, as is known in the industry, may typically include not only rock, gravel and sand but may also contain contaminants such as wood, leaves, paper, plastic, shale, clay, and other undesirable constituents. Most desirably, the undesirable constituents will be separated from the rock, sand and gravel. The rock, gravel and sand will each be further separated into size classifications, for later use as is known in the industry. 
     Rotary aggregate washing and classification system  10  is comprised by several main components. These include inlet  20 , rotary screen and auger  30 , rock receiver  40 , sand classifier  50 , and water flow control  60 . Inlet  20  is operative to receive aggregate in an “as-delivered” state, which may come directly from an adjacent gravel pit, or which may be delivered from a distance, such as by truck or rail. As will be described herein below, one of the advantages of the present invention is the mobility which is inherent. The preferred rotary aggregate washing and classification system  10  may be readily transported from location to location, thereby facilitating the processing of aggregate from smaller gravel pits without requiring the aggregate to be transported to another processing facility. Consequently, in many instances the source for aggregate passing into inlet  20  will be a loader, shovel or other equipment within the gravel pit. Depending upon the quality and size of the source matter, in some cases the matter may be passed through a crusher prior to introduction into inlet  20 . To better control the rate of feed into inlet  20 , it may also be desirable to meter the source matter onto a conveyor belt or the like, or use other suitable means to maintain a steady feed of source matter into inlet  20 . Finally, it may also be desirable to add water into either the aggregate or to inlet  20  together with the aggregate, which will assist with ensuring proper flow of matter without undesirable clogging. 
     Aggregate is first received within aggregate inlet funnel  21 , and then passes into a narrower neck region  22 . At the lower end of neck region  22 , the aggregate will first be exposed to water within rotary aggregate washing and classification system  10 , which will desirably be maintained at a level illustrated in the figures as water line W. The aggregate will then continue to drop into holding region  23 , prior to passing into rotary screen and auger  30 . A sloped infeed surface  24  helps to ensure gravity-driven automatic feeding into rotary screen and auger  30 . In operation, the primary water outlet for water that has passed through rotary aggregate washing and classification system  10  is water outlet  25 . As will be described in more detail herein below, fresh water is pumped into rotary aggregate washing and classification system  10  through water inlets  44 - 46 , and may circulate an indeterminate number of times within rotary aggregate washing and classification system  10 . The water will ultimately pass out of water outlet  25 . Since water outlet  25  is located immediately adjacent to aggregate inlet funnel  21 , as aggregate passes through neck region  22  into submersion, lighter materials such as wood, leaves, paper and other undesirable trash will float up and eventually pass into water outlet  25  with water flow  82 . In addition, materials such as very fine silt which remain fully suspended in the water will also be carried out with flow  82 . With appropriate flow rates and patterns, even matter closer in density to the desired sand, rock and aggregate product may be separated at the inlet, including such matter as shale and clay. 
     Most preferably, inlet  20  will never be fully filled, as this might undesirably trap lighter materials in the aggregate. Instead, turbulence within water adjacent to neck  22  is often quite desirable, which will assist with the separation of materials which float. Specific arrangements of in-feed belts carrying matter, feed and flow rates, and other factors may be adjusted to optimize a given apparatus for a particular source matter, to most efficiently process that material. 
     Aggregate, which has now desirably been separated from wood, paper, leaves and the like, will next be drawn into rotary screen and auger  30  from adjacent holding region  23 . In operation, motor  39  will drive and rotate shaft  38  relative to the outer wall of rotary aggregate washing and classification system  10 . Shaft  38  is in turn coupled to auger shaft  37 , which carries auger  32 , such as an Archimedes screw, thereon. Supported circumferentially about auger  32  are a set of screens  33 - 36 , which get progressively coarser as aggregate passes from holding region  23  to the eventual rock outlet  31 . Support for auger  32  and screens  33 - 36  may include various types of known and suitable bearings. 
     Screens  33 - 36  will most preferably be manufactured from a durable and abrasion resistant material such as, but not limited to, polymers and various metals and metal-alloys, either plated or unplated, and coated or otherwise. In one preferred embodiment, screens  33 - 36  may be fabricated from expanded metal, which may be coated, plated or otherwise protected from corrosion and wear, such as with a polyurethane, PVC or any other suitable material. Further, in the case of the expanded metal and with other materials as suitable and desired, it is known that the forming process causes the metal to twist out of the plane of the web of metal. So, small segments of the metal are each angularly offset from tangent about the center, each small segment offset in the same direction. In this special case, it may be further desired to orient the angular offset such that it approaches a vertical angle sometime after passing through the six o&#39;clock position, such as when approximately adjacent to the seven or eight o&#39;clock position, when viewed from rotational axis and when rotating in that view clockwise. While not being bound to a particular theory, this is believed to permit the appropriately sized and cleaned product to drop through the screen as the aggregate is being lifted against the force of gravity, where otherwise the angular offset would tend to hold material into the screen during the upward movement of the screen. 
     Rotary motion is coupled from auger shaft  37  through any suitable means to auger  32  and screens  33 - 36 , such as one or more stub shafts or the like that, for exemplary purposes only and not limited thereto, may extend radially between auger shaft  37  and either or both auger  32  and screens  33 - 36 . The benefit of a relatively small axial auger shaft  37  is that it provides strength and rigidity in the axial direction, while, if smaller than the inner diameter of auger  32 , permitting flow of water through the center of auger  32 . This flow of water directly through the core, which may be counter to the direction of aggregate movement, is preferable for some applications. 
     Auger  32  is rotated by the action of motor  39 , as already described, and will in turn carry aggregate through rotary screen and auger  30  from adjacent holding region  23 , gradually raising the aggregate to levels closer to and eventually above water line W. In this way, any rocks large enough to avoid passing through final screen  36  will finally be dropped out of open end  31 . Such larger rocks may be sorted further if desired, but in some instances will alternatively be passed through a crusher or the like, and then the resulting aggregate will once again be introduced back into aggregate inlet funnel  21 . While only one rotary screen and auger  30  is illustrated, it will be apparent to those reasonably skilled in the art that a plurality of rotary screen and auger units may be combined in one machine, or that a plurality of separate augers  32  may be provided within a common, circumscribing screen. Furthermore, the direction of rotation of the augers, either individually or with respect to each other, is not critical to the operation of the invention, so long as the material is satisfactorily transported, as is known in the material handling arts. Consequently, the augers may be either counter-rotating or rotating in the same direction. 
     As the aggregate traverses rotary screen and auger  30 , sand and gravel will pass through screen  33 , while the smallest rock will not be dropped out until encountering screen  34 . Generally circumscribing the lower side of screen  34  is the first of three rock chambers  41 - 43  within rock receiver  40 . These chambers are used to collect and store the rocks, until later discharged through a side or bottom door (not illustrated). In one conceived embodiment, each separate rock chamber will further be provided with a false bottom, a scale monitoring the load upon the false bottom, and electrical controls, to permit both monitoring of the fill levels within each rock chamber, and also to permit discharge of selected amounts of rock therefrom through automated or computer control. 
     As an alternative to the use of doors or gates, it is further contemplated herein that additional augers may be provided which couple into one or more of the chambers  41 - 43 . These additional augers may be used to remove product from the chambers when desired, such as through a proportional metering, or may alternatively be operative continuously to discharge the product. The augers, including rotary screen and auger  30 , may also be provided with scoops at the ends thereof to couple product into slides, chutes or the like, as may be desired. 
     Along the bottom of rotary aggregate washing and classification system  10  is a preferred sand classifier  50 , which has a number of funnels  51 - 54  and associated outlets  55 - 58  which are used to selectively release sand therefrom. Once again, outlets  55 - 58  may be replaced by, or additionally provided with discharge assists such as additional augers, chutes and skids, or other suitable apparatus, similar to that already discussed with regard to chambers  41 - 43 . Operation of sand classifier  50  is provided by water flow control  60 , which controls the flow of water within rotary aggregate washing and classification system  10  to operate sand classifier  50  in a manner such as is known in the prior art as a horizontal flow, gravitational separator. 
     Sand passing through finer screen  33  will drop into a water flow stream having a flow direction illustrated by arrow  71 , and limited by baffle  62 . As the water and sand approach baffle  63 , the water flow will divide, as shown by arrows  72  and  73 , with flow  72  carrying most of the larger sand and gravel. Finer silt that remains suspended will be carried within flow  74  or flow  76  to an inlet to pump  61  defined by baffle  64 . The outlet for pump  61  is defined by flow  77 , which will be greatly accelerated relative to the other adjacent flow path. This acceleration will carry not only flow path  77 , but also gravel suspended within flow  75 , horizontally along flow path  78 , passing over funnels  51 - 54  in order. Larger gravel will drop first, falling into funnel  51 , with finer gravel being carried into funnel  52 . Since baffle  62  has a slight slope, flow  79  will be moving slower than flow  78  was. As a result of the gradual deceleration of flow farther from pump  61 , and the continued action of gravity on the more dense sand within the water, progressively finer materials will continue to drop from the flow as the flow continues. Adjacent flow  79 , there will be a slight and slow eddy  81  developed, which will tend to drop the most fine sand, and there will also be a return flow  80  which forms a confluence with flow  71 . 
     In addition to the flow generated by pump  61 , a second flow is produced by the introduction of water through inlets  44 - 46 . This fresh water serves to not only continue to keep rocks within chambers  41 - 43  clean and fresh, but also generates a flow of water which is counter to the direction of movement of aggregate within rotary screen and auger  30 . This counter flow serves to prevent silt from passing into rock chambers  41 - 43  with the aggregate, and additionally moves the lighter materials in the direction of water outlet  25 . The general flow of water from inlets  44 - 46  towards water outlet  25  will also couple with flow  71 , and is encouraged to do the same by turbulence generated by auger  32 . As a result of this turbulence, there is a certain amount of mixing of water circulating through sand classifier  50  and water circulating through rotary screen and auger  30 . 
     Most preferably, auger  32  will have a variable pitch, which may be varied in discrete steps or may be continuously varied. Most preferably, adjacent finer screen  33  auger  32  will move material more quickly towards outlet  31 . Adjacent each progressively coarser screen  34 - 36 , auger  32  will move material more slowly towards outlet  31 , to where, adjacent outlet  31  and screen  36 , any remaining rock is tumbled more, while traveling the least towards the outlet. One consideration in the design of the variable pitch is the consideration of the amount of active screen. For example, if the initial aggregate is comprised of 80 percent fine sand which passes through screen  33 , than the initial screen  33  will have 80 percent of the received material actively passing through at a given moment. However, as the aggregate progresses towards the outlet, less of the fine sand remains, reducing the amount of active screen surface, and thereby requiring more time for removal. As an adjunct to this principle, it is recognized herein that the screens may be varied in surface area, diameter, and even geometric outline to better optimize performance for a particular source material having particular size range or other characteristic that affects the proportion of processing times needed for a given stage. 
       FIG. 2  illustrates a second preferred embodiment rotary aggregate washing and classification system  110 . Where possible, like numbers have been used which have the same digits in the tens and ones places as those numbers which correspond to like elements in  FIG. 1 . So, for example, aggregate inlet funnel  121  in rotary aggregate washing and classification system  110  performs similar function to aggregate inlet funnel  21  in rotary aggregate washing and classification system  10 . This numbering is preferentially used, and where functions are alike or similar enough, no further discussions are provided herein for brevity. 
     As may be seen in  FIG. 2 , a special baffle  126  is provided within neck region  122  which serves to deflect aggregate away from the entrance to rotary screen and auger  130 , and instead towards water outlet  125 . This deflection enhances the shear and separation of lighter materials. When properly designed, and when accompanied by automated aggregate feeders such as belt feeders that load aggregate into inlet  120 , special baffle  126  will provide sufficient assist to enable the separation of shale and the like within inlet  120 , for discharge directly out of water outlet  125 . 
     A second difference between rotary aggregate washing and classification system  10  and rotary aggregate washing and classification system  110  is found in the circulation of water therein, and the placement and orientation of baffles therein. As can be seen in  FIG. 2 , vertical baffles  162 - 164  (and beyond) are provided. Water flow remains in the direction of rock receiver  140  to outlet  125 , similar to that of  FIG. 1 , above vertical baffles  162 - 164 . However, below these baffles, water flow is reversed between the two preferred embodiments. More particularly, in rotary aggregate washing and classification system  110 , water will flow from rock receiver  140  along a flow  171  above vertical baffles  162 - 164 . Below vertical baffles  162 - 164 , water also flows parallel in direction to flow  171 , this time along flow  178 . Vertical baffles  162 - 164  prevent the turbulence created by rotation of auger  132  from interfering with proper vertical dropping of sand and aggregate from rotary screen and auger  130 . In this embodiment, more screen sizes will preferably be provided adjacent inlet  120 , shown as  133  and  133 ′. While only two screens are illustrated, it will be understood herein that only one or more than two may be provided, with no limit on the number other than that which is economically justified and on the desired ultimate length of rotary aggregate washing and classification system  110 . The finest material will still be carried along flow  178  around vertical baffle  162 , and will drop into funnel  151 . 
     It should now be apparent that while a single funnel  151  is illustrated for collection and recovery of finer sand, rotary aggregate washing and classification system  110  may be extended as desired to permit placement of additional baffles and funnels to the left of funnel  151  shown in the figure. In such case, everything under and including rotary auger  130  would remain as illustrated. However, holding region  123  would be enlarged to the left, along the longitudinal axis of rotary aggregate washing and classification system  110 . Additional funnels similar to funnel  151  would then be provided thereunder, permitting any number of classifications to be made therein, limited only by the ultimate length chosen for rotary aggregate washing and classification system  110 . Since rotary aggregate washing and classification system  110  will most preferably be transportable along a roadway, such length will be determined by the size and weight restrictions placed upon the roadways for a given locale. 
     Since the flow of water within rotary aggregate washing and classification system  110  is generally opposite the movement of aggregate, and is unidirectional, fresh water must be continually provided at water inlets  144 - 146 , and will continually be taken from water outlet  125 . While it is conceivable in certain environments and climates to draw from a clean fresh water source such as a lake, pond, reservoir, or even flooded quarry, in other instances it will be preferable to provide a separate holding pond or tank exterior to rotary aggregate washing and classification system  110 , into which effluent from flow  182  will pass, and be allowed to settle. In turn, such holding tank or pond will then be drawn from, at different location, to pump back into water inlets  144 - 146 . In yet a third conceived alternative, in some instances it may still be preferred to provide a recirculating pump similar to pump  61  of  FIG. 1 . In this instance, the recirculating pump will most preferably draw adjacent to motor  139 , and pump the water back into flow  179  adjacent rock chamber  141 . 
     A third significant change between the two embodiments is found in rock receiver  140 . As shown in  FIG. 2 , rock receiver  140  includes three separate and free-standing rock chambers  141 - 143 , each which are preferably supported upon a scale, thereby keeping the chambers separate from fixed components within rotary aggregate washing and classification system  110 . Consequently, the weight of each may be measured independently, and so the amount of aggregate located therein may be determined. With this configuration, these rock chambers  141 - 143  may be devised to unload from the bottom into and through the underlying funnels. Once again, the amounts present, fill levels, and unloading may all be automatically or numerically controlled. 
     As discussed herein above, rotary aggregate washing and classification system  10  may be supported upon a wheel set, together with a base which may be used as a stand once rotary aggregate washing and classification system  10  is transported to a point of use. As mentioned herein above, most preferably rotary aggregate washing and classification system  10  is designed to be mobile. Transport will most preferably occur when rotary aggregate washing and classification system  10  is either nearly or completely empty, thereby reducing the weight upon a roadway and hazards associated with a heavy load. With the preferred configurations, each of the rotary aggregate washing and classification systems  10 ,  110  may be fully unloaded relatively easily prior to transport, simply by emptying each of the sand and rock funnels. 
     While the foregoing details what is felt to be the preferred embodiment of the invention, no material limitations to the scope of the claimed invention are intended. Further, features and design alternatives that would be obvious to one of ordinary skill in the art are considered to be incorporated herein. For exemplary purposes only, and specifically not limited solely thereto, rotary auger  130  is illustrated as being tilted slightly with respect to the top of rock receiver  140  and the water level W. However, rotary auger  130  could alternatively be fabricated to be parallel with the top of rock receiver  140 , and the entire rotary aggregate washing and classification system  110  could then be tilted to achieve the same effect. Consequently, the scope of the invention is set forth and particularly described in the claims herein below.

Technology Classification (CPC): 1