Abstract:
A method for processing unseparated egg shells includes placing unseparated egg shells in a separation tank containing fluid, applying cavitation to the unseparated egg shells in the fluid to thereby separate the egg shell membranes from the egg shells, and recovering the egg shell membranes. An apparatus for processing unseparated egg shells includes a separation tank for holding a fluid, a recirculating loop operatively connected to the separation tank, and at least one submersible mixer in the recirculating loop to recirculate the fluid and egg shell membranes and egg shells within the fluid. The apparatus further includes a membrane collection conveyor for conveying egg shell membranes from the separation tank and a shell conveyor positioned beneath the separation tank for conveying egg shells away from the separation tank.

Description:
RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 12/512,453, filed Jul. 30, 2009, now U.S. Pat. No. 7,954,733, which is a Continuation of U.S. patent application Ser. No. 11/333,697 filed Jan. 17, 2006, now U.S. Pat. No. 7,584,909, which claims priority to U.S. Provisional Patent Application No. 60/644,643, filed Jan. 18, 2005, both of which are incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to methods, apparatus, and a system for egg shell membrane separation and a purified form of egg shell membranes produced by the separation method. The present invention addresses a number of different problems, some of which may seem unrelated without having the benefit of this disclosure. The problems include, but are not limited to, the costs associated with landfill disposal of egg shell membranes, the need for elemental calcium for various uses, and the need for the constituent components found in egg shell membranes. Some of these problems are discussed in U.S. Pub No. 2003/0209617A1 to MacNeil, U.S. Pat. No. 6,649,203B1 to Thoroski, U.S. Pub No. 2004/0166213A1 to Thoroski, and U.S. Pat. No. 6,790,454B1 to Abdul Malak et al, all of which are incorporated by reference herein, each in its entirety. 
     In the U.S., there has been increased consumption of eggs during the 1990s. In 1997, over 5,000 tons of egg shell membranes have been available on the U.S. market. A related problem to the processing necessary to support this magnitude of egg processing is the cost for landfill disposal of egg shell membranes. This waste material created additional problems as it is further observed that this type of hatchery waste material is considered to be odiferous. 
     Egg shell powder is used in the food industry, including animal and human nutritional supplements. Egg shells provide approximately 36-37 percent elemental calcium in addition to traces of phosphorous and other trace elements. In addition to potential uses of the egg shell, the egg shell membrane is known for being rich in a number of different materials, including, without limitation collagen, hyaluronic acid, lysine, histidine, arginine, threonine, glutamic acid, proline, glysine, cysteine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine and tryptophan. Some of these materials are well known as high value materials, yet due to various problems, these materials go to waste. Despite the general recognition of the tremendous potential value of egg shell membranes when its constituents are extracted, little has been done to realize this value. Thus hatchery waste continues to include unseparated egg shells which is still being sent to land fills. There are numerous problems that prevent the use of egg shell membranes. Including problems which prevent hatcheries or egg breaking facilities from separating egg shell membranes in a useable form. There are specific problems in the context commercial context which provide additional challenges not present in a laboratory environment. 
     One problem relates to the need for a production process for egg shell membrane separation which is continuous. In the hatchery environment or egg breaking facility environment, waste is being continuously produced, and therefore it would be highly desirable for egg shell membranes to be separated from egg shells continuously as well. To not do so, would create significant problems in that either the hatchery or egg breaking operations would be slowed, not all waste would be processed, waste would need to be processed when other hatchery operations were offline, or similar problems which would be unacceptable in the such environments. 
     Therefore it is a primary object, feature, or advantage of the present invention to improve upon the state of the art. 
     It is a further object, feature, or advantage of the present invention to reduce waste used in egg processing. 
     Another object, feature, or advantage of the present invention is to produce egg shell powder from what would otherwise be egg processing waste material. 
     Yet another object, feature, or advantage of the present invention is to produce high value products such as collagen, hyaluronic acid, or other types of polypeptides from what would otherwise be egg processing waste material. 
     A still further object of the present invention is to produce new revenue streams for hatcheries and egg producers. 
     Yet a further object, feature, or advantage of the present invention is to provide a method for separating egg shell membranes from egg shells. 
     A still further object, feature, or advantage of the present invention is to provide a method that reduces pathogens and contaminants in egg shell membranes. 
     A further object, feature, or advantage of the present invention is to provide for continuous processing of egg shells. 
     Another object, feature, or advantage of the present invention is to provide for automated processing of egg shells. 
     Yet another object, feature, or advantage of the present invention is to provide for methods, apparatus, and systems for processing egg shells that are scaleable. 
     A further object, feature, or advantage of the present invention is to provide for methods, apparatus, and systems for processing egg shells that are cost effective. 
     A still further object, feature, or advantage of the present invention is to provide for methods, apparatus, and systems for processing egg shells that does not damage collagen, hyaluronic acid or other materials to be extracted from egg shell membranes. 
     A still further object, feature, or advantage of the present invention is to provide for a method of processing egg shells which allows extraction processes to be performed on egg shell membranes at locations remote from egg hatcheries or egg breaking facilities. 
     One or more of these and/or other objects, features, and advantages of the present invention will become apparent from the specification and claims that follow. 
     BRIEF SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a method for processing unseparated egg shells is provided. The method includes placing unseparated egg shells in a separation tank containing fluid, applying cavitation to the unseparated egg shells in the fluid to thereby separate the egg shell membranes from the egg shells, and recovering the egg shell membranes. 
     According to another aspect of the present invention, an apparatus for processing unseparated egg shells is provided. The apparatus includes a separation tank for holding a fluid, a recirculating loop operatively connected to the separation tank, and at least one submersible mixer in the recirculating loop to recirculate the fluid and egg shell membranes and egg shells within the fluid. The apparatus further includes a membrane collection conveyor for conveying egg shell membranes from the separation tank and a shell conveyor positioned beneath the separation tank for conveying egg shells away from the separation tank. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram which provides an overview of one embodiment of the system of the present invention. 
         FIG. 2  is a block diagram showing perspective view illustrating one embodiment of the present invention. 
         FIG. 3  is view of an apparatus for separation of egg shells from egg shell membranes using cavitation. 
         FIG. 4  is a top view of the apparatus for separation of egg shells from egg shell membranes shown in  FIG. 3 . 
         FIG. 5  is a sectional view illustrating the bottom of the separation tank and its relationship to the shell drag conveyor shown in  FIGS. 3 and 4 . 
         FIG. 6  is a perspective view showing the diverter shield within the separation tank. 
         FIG. 7  is a block diagram illustrating one embodiment of a control system for controlling the processing of unseparated egg shells. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention provides for separation of egg shell membranes from egg shells in a manner which provides for significant advantages and benefits. In particular, but without limitation, the present invention provides for separation of egg shell membranes from egg shells in a manner which allows for continuous processing such that the separation can occur at a hatchery or egg-breaking facility, in a manner which prevents damage to constituent components within the egg shell membranes (such as, but not limited to collagen or hyaluronic acid or other constituent components of egg shell membranes). 
       FIG. 1  is a block diagram which provides an overview of one embodiment of the system  10  of the present invention. As shown in  FIG. 1 , waste  12  such as from a hatchery or egg-breaking facility is received. The waste  12  consists of unseparated egg shells and egg shell membranes that remain after the cracking process. Although the term “unseparated” is used, it is to be understood that there may be some degree of separation at this point. This waste  12  is received at a mill component  14 . The mill component  14 , if used, may provide for greater uniformity in particle size. The mill component  14  may produce uniformly sized waste particles  15 . The uniformly sized waste particles  15  of unseparated egg shells and egg shell membranes are received at an egg shell membrane separation component  16 . The present invention contemplates numerous embodiments for the egg shell membrane separation component  16 , and preferred embodiments will be described in greater detail later herein. It is preferred that the egg shell membrane separation component  16  provide for continuous processing of hatchery or egg breaking facility waste  12 . The egg shell membrane separation component  16  outputs egg shell membranes  24  and egg shells  18  each type of resulting product may then be separately processed. The egg shells  18  may be conveyed to a grinding component  20  in order to produce egg shell powder  26 . The egg shell powder  26  can be used in numerous ways, including in animal nutrition, in human nutritional supplements, or for use in other applications. The grinding component  20  may be configured to grind the egg shell powder  22  into particulate sizes consistent with the use of the egg shell powder  26 . 
     The egg shell membranes  24  may then be processed for any number of uses. The present invention contemplates that the egg shell membranes  24  may be processed onsite, or may be stored or transported  27  to another site. One type of processing that may be performed uses an extraction component  28 . The extraction component  28  provides for extracting, isolating, or recovering one or more materials from the egg shell membranes. Although various types of polypeptides may be extracted, of particular interest is collagen  30 , and various amino acids  32 , including hyaluronic acid (HA)  30 . Such materials are high value materials which are difficult and/or expensive to obtain from other sources. Other types of processing that may be performed can include solubilizing the egg shell membrane  24 , fermenting the egg shell membrane  24 , or otherwise processing the egg shell membrane  24 . 
       FIG. 2  is a block diagram which provides an overview of an embodiment of the present invention. In  FIG. 2 , a hatchery or egg breaking facility  34  is shown which produces unseparated egg shells. These unseparated egg shells may be conveyed to a knife mill  36 . One way of conveying unseparated egg shells to the knife mill  36  is by an auger where the apparatus of the present invention is located onsite. The knife mill  36  may be used to reduce the size of the unseparated egg shells. The reduced size unseparated egg shells then enter the separator  38 . the separator  38  separates into egg shells and egg shell membranes. The egg shell membranes may then go through a belt press  40  to remove moisture from the membranes, and may then be conveyed by conveyor  42  into collection containers or to further processing. The egg shells may be conveyed by a conveyor  44  from the separator  38 , to a dryer  46  or further processing. 
       FIG. 3  is a view of one embodiment of a system  50  of the present invention. The system  50  includes a separation tank  52 . Separation of egg shells and egg shell membranes occurs in the separation tank  52  through the application of cavitation. A recirculating loop  54  is also shown with submersible mixers  56  positioned within the recirculating loop  54 . Unseparated egg shell and egg shell membranes are placed within the separation tank  52 . A fluid mixture is also present in the tank. The fluid mixture may consist of water although other types of fluid may be used. The submersible mixers  56  positioned within the recirculating loop  54  create cavitation in the fluid which causes the egg shell membranes to separate from the egg shells. Once the separation occurs, then the egg shell membranes and the egg shells are separately recovered. 
     In the embodiment shown in  FIG. 3 , an outlet  55  of the recirculating loop  54  is shown through which the fluid mixture which includes egg shells and egg shell membranes may enter the separation tank  52 . Proximate the outlet  55  is a diverter shield  58 . The diverter shield  58  diverts the fluid hitting the diverter shield  58  in a more downwardly direction towards the bottom of the separation tank  52 .  FIG. 6  provide a perspective view showing one example of the positioning of the diverter shield  58  within the separation tank  52  and relative to the outlet  55  of the recirculating loop  54 . 
     At the bottom of the separation tank  52  are a series of paddles  74 . The paddles  74  assist in providing a washboard effect. The bottom of the tank acts as a washboard to assist in lifting the membrane. Thus, the membrane stays in suspension in moving water. This configuration assists in delaying the sinking of egg shell particles immediately to the bottom of the tank. Thus, this allows the egg shell particles to be washed several times before the egg shell particles reach the paddles on the bottom of the tank. This configuration also avoids egg shell particles trapping membrane particles at the bottom of the tank.  FIG. 5  provides a sectional view showing that the egg shell particles fall through openings  80  in a sieve  82 . 
     The egg shell membranes stay in suspension in the moving water which directs the egg shell membranes towards a membrane collection conveyor  66 . An arrow  62  illustrates the direction of travel of a mesh belt  64  on the conveyor  66 . An arrow  65  indicates the direction of rotation of the mesh belt  64  on the conveyor  66 . The mesh belt  64  allows fluid to drain, leaving only the egg shell membranes. A plurality of rollers  66  are shown. When moist, the egg shell membranes tend to stick to the belt  64  and thus gravity is not sufficient to remove the egg shell membranes. The rollers  66  contact the membrane to release the membranes from the belt  64 . Once the membranes are released from the belt  64 , the membranes may be removed to a belt press. The belt press provides for further removing moisture from the egg shell membranes. 
     The egg shell particles settle from the bottom of the tank  52  through a sieve  82  into a tube or pipe  76  in which a drag conveyor  68  is positioned. The drag conveyor  68  moves in the direction of travel indicated by arrow  72  and with rotation indicated by arrow  70 . As the egg shell particles are conveyed in an upward direction, the water is left behind. Thus, in this manner the egg shell particles are separated out of the fluid mixture. 
       FIG. 4  is a top view of the system  50  which assists in illustrating the recirculation of the fluid. The placement of the mixers  56  in the pipe or tube  54  provide for flow of fluid in the direction indicated by arrow  86 . A feed connection  84  is shown which allows for incoming unseparated egg shells to be received into the tube  54 . The incoming unseparated egg shells may, for example, be fed into the system  50  by an auger coming directly from an egg breaking facility. 
     The present invention contemplates that the egg shell membrane separation process may be under electronic control.  FIG. 7  is a block diagram illustrating one embodiment for electronic control. In  FIG. 7 , a control system  100  is shown which includes an intelligent control  102 . The intelligent control  102  may be implemented using a computer, processor, microcontroller, or other type of intelligent control. Sensors may be electrically connected to the intelligent control  102 . Examples of sensors may include a water sensor  104  for sensing fluid levels within the separation tank, a flow meter  110  for sensing rate of flow, and motor sensors  118  for sensing the status of different motors throughout the system. In addition, the intelligent control  102  is operatively connected to conveyors  120 , augers  112 , a knife mill  108 , a spray pump  116  for controlling operation of these devices. A touchscreen display  114  may be operatively connected to the intelligent control system to allow an operator to control the separation system. In addition a siren  106  may be operatively connected to the intelligent control system to provide an alarm upon detection of an alarm condition within the system. Of course, other types of sensors may be used throughout the system to monitor the status of components of the system. Similarly, addition devices may be electronically controlled by the system as may be appropriate within a particular embodiment. 
     Although specific embodiments of the present invention are provided herein, the present invention is not to be limited to these embodiments. The present invention contemplates numerous variations in the specific methodology used and the specific structures used. One skilled in the art having the benefit of this disclosure will understand that numerous variations and substitutions are within the spirit and scope of the invention.