Abstract:
A system for enhancing the cooling of a product stream, wherein the product stream is a livestock feed product, is disclosed. The system has a reduction station and a conveyor system with a conveyor belt routed through the reduction station. The conveyor belt is used to transport the product stream through the reduction station. The reduction station increases the surface area to volume ratio of the product stream.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates to a system and method for cooling a product stream during its production.  
         BACKGROUND OF THE INVENTION  
         [0002]    Feed supplements have been used for many years as vehicles to provide energy, protein, minerals, vitamins and medicaments to animals, especially livestock. Molasses-based feed supplements have been an especially popular and effective form of livestock feed supplement. Since molasses is highly palatable to livestock, a molasses-based feed supplement must be consumption limiting to prevent livestock from over indulging in any one visit to the supplement.  
           [0003]    One method of making a molasses-based feed supplement consumption limiting is to provide it to livestock in the form of a hard and durable low-moisture feed block. Low-moisture feed blocks are made by heating a fluid mixture of molasses and other nutrients until the mixture is fully dehydrated. The mixture is then poured into a form or tub and cooled.  
           [0004]    While heating is necessary to fully dehydrate a molasses-based feed supplement to achieve a feed block that is hard and durable, heat causes thermal degradation of sugars such as those found in molasses. Heat also causes thermal degradation of the nutrients contained in the feed supplement, creating reaction products that are often indigestible to the animals eating the feed supplement. Thermal degradation is especially problematic for processors of molasses-based feed supplements because the molasses supplied to feed supplement processors often vary from supply to supply. As a result, it can be difficult to fine-tune the dehydration process so as to minimize thermal degradation.  
           [0005]    The longer the feed supplement remains in a heated state, the greater the thermal degradation of the sugars and nutrients and the greater the creation of indigestible reaction products. Failure to adequately decrease the temperature of the feed supplement prior to placing the supplement in a form or barrel can cause the supplement to react and to increase its temperature on its own. This can result in complete degradation of the supplement. Complete degradation of the supplement is more likely to occur when the supplement is manufactured during high ambient temperature conditions. Thus, it is advantageous to rapidly reduce the temperature of the molasses-based feed supplement once the supplement has exited the dehydration process.  
           [0006]    There is a need in the art for a system and method that rapidly reduces the temperature of a fully dehydrated molasses-based feed supplement once the supplement has exited the dehydration process.  
         BRIEF SUMMARY OF THE INVENTION  
         [0007]    The invention, in one embodiment, is a system for enhancing the cooling of a product stream during production wherein the product stream is a livestock feed product. The system has a squeeze roller and a conveyor system with a conveying belt. The squeeze roller is located above the conveyor belt. A livestock feed product is routed between the conveyor belt and the squeeze roller thereby reducing the product in height and increasing the product in width. This is done to facilitate cooling of the product stream.  
           [0008]    The invention, in another embodiment, is a system for increasing the surface area of a product stream wherein the product stream is an animal feed product to be cooled. The system has a reduction station and a conveyor system. The conveyor system has a conveyor belt routed through the reduction station. The conveyor belt is used to transport the product stream through the reduction station. The reduction station reduces the product stream in height and increases the product stream in width.  
           [0009]    The invention, in yet another embodiment, is a method for increasing the surface area of a product stream wherein the product stream is an animal feed product to be cooled. The product stream is directed onto a conveyor belt and conveyed to a reduction station. The reduction station reduces the height of the product stream and increasing the width of the product stream as the product stream is conveyed through the reduction station.  
           [0010]    While multiple embodiments are disclosed, still other embodiments of the invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the invention is capable of modifications in various obvious aspects, all without departing from the spirit and scope of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a schematic side view of a product cooling system incorporating a cooling belt conveyor and a series of squeeze rollers that reduce a product stream in height and increase the product stream in width, thereby increasing the surface contact between the product stream and the cooling belt.  
         [0012]    [0012]FIG. 2 is a schematic plan view of the system shown in FIG. 1.  
         [0013]    [0013]FIG. 3 is a schematic side view of product cooling system incorporating a squeeze belt conveyor reducing a product stream in height and increasing the product stream in width before the product stream reaches the cooling belt conveyor.  
         [0014]    [0014]FIG. 4 is a schematic side view of the product cooling system incorporating an inclined squeeze belt conveyor reducing a product stream in height and increasing the product stream in width before the product stream reaches the cooling belt conveyor.  
         [0015]    [0015]FIG. 5 a  is a block diagram illustrating a method of increasing the surface area contact between a product stream and a conveyor belt.  
         [0016]    [0016]FIG. 5 b  is a block diagram illustrating a method of automatically adjusting the surface area contact between a product stream and a conveyor belt based on a temperature reading taken from the product stream.  
         [0017]    [0017]FIG. 6 is a schematic plan view of the system shown in FIG. 1 employing chilled squeeze rollers. 
     
    
     DETAILED DESCRIPTION  
       [0018]    [0018]FIG. 1 is a schematic side view of a product cooling system  5  according to one embodiment of the invention. As shown in FIG. 1, the system  5  includes a cooling belt conveyor  10 , a reduction station  15 , a product barrel  20 , and a hopper  25  with an orifice  26 . The hopper  25  is located above one end of the cooling belt conveyor  10  and the product barrel  20  is located below the other end of the cooling belt conveyor  10 . The reduction station  15  is located at a point along the cooling belt conveyor  10  between the hopper  25  and the barrel  20 .  
         [0019]    A product stream  27 , the product being a fully dehydrated molasses-based feed supplement or other similar animal feed product, emanates from the orifice  26  of the hopper  25  onto the cooling belt conveyor  10 . The cooling belt conveyor  10  transports the product stream  27  through the reduction station  15  where the product stream  27  is reduced in depth and increased in width. This facilitates cooling of the product stream  27  because the surface contact between the cooling belt conveyor  10  and the product stream  27  is increased. After leaving the reduction station  15 , the product stream  27  travels along the cooling belt conveyor  10  to the product barrel  20  or form.  
         [0020]    The cooling belt conveyor  10  includes a cooling belt  30 , conveyor wheels  35  and a cooling water spray system  40 . The cooling belt  30  travels about the conveyor wheels  35 . The cooling belt  30  is stainless steel or another material also having good heat transfer and product release capabilities.  
         [0021]    As shown in FIG. 2, the cooling belt is powered by one or more electric motors  42 . As further indicated in FIG. 2, in one embodiment of the invention, the electric motor  42  has a variable frequency drive (VFD)  44  that allows the cooling belt  30  to travel at different speeds. For example, in one embodiment, the VFD  44  causes the cooling belt  30  to travel at approximately 1 to approximately 30 feet per minute. In another embodiment, the cooling belt  30  travels at a speed of approximately 30 to approximately 60 feet per minute. In another embodiment, the cooling belt  30  travels at a speed of approximately 60 to approximately 100 feet per minute. In another embodiment, the cooling belt  30  travels at a speed of approximately 100 feet per minute or greater. In another embodiment, the cooling belt  30  travels at a speed of approximately 60 feet per minute.  
         [0022]    The length of the cooling belt conveyor  10  may vary depending on the desired temperature drop of the product being cooled, the temperature of the water in the cooling water spray system  40 , and the travel speed of the cooling belt  30 . For example, in one embodiment of the invention, the cooling belt conveyor  10  is between about 10 and about 150 feet long or longer. In another embodiment, the cooling belt conveyor  10  is approximately 50 feet long. In other embodiments of the invention, the conveyor will be greater than or less than 50 feet long.  
         [0023]    The width of the cooling belt  30  may vary depending on the width of the product stream  27  emanating from the orifice  26  of the hopper  25 . For example, in one embodiment of the invention, the cooling belt  30  is between about 4 and about 48 inches wide or wider. In another embodiment, the cooling belt  30  is between about 12 and about 36 inches wide. In another embodiment, the cooling belt  30  is between about 18 and about 30 inches wide. In another embodiment, the cooling belt  30  is about 24 inches wide. Finally, in another embodiment, the cooling belt  30  is about 30 inches wide.  
         [0024]    As shown in FIG. 1, the cooling water spray system  40  is located within the cooling belt conveyor  10  and has water piping  45  terminating in spray heads  50 . To cool the cooling belt  30 , water spray  55  emanates from the spray heads  50  and contacts the bottom surface of the cooling belt  30 . In one embodiment of the invention, the water used in the cooling water spray system  40  is water pumped from underground aquifers. This ground water exits the spray heads at approximately 50 to approximately 65 degrees Fahrenheit. In another embodiment, the ground water would be approximately 58 to approximately 62 degrees Fahrenheit.  
         [0025]    In one embodiment, the water used in the cooling water spray system  40  is chilled water from a chiller. The chilled water may exit the spray heads  50  at approximately 40 to approximately 55 degrees Fahrenheit. In other embodiments, the water temperature may be higher or lower than these values. In one embodiment, other cooling mediums are applied against the bottom of the cooling belt  30 , for example brine solutions or cooled air. In one embodiment of the invention, jets of cooled air blow down on the top of the product stream  27  as it travels along the cooling belt conveyor  10 .  
         [0026]    In one embodiment of the invention, the cooling belt conveyor  10  utilizes about 0.01 to about 10.0 gallons per minute (gpm) of cooling water per linear foot of the cooling belt conveyor  10 . In another embodiment, the cooling belt conveyor  10  utilizes about 0.05 to about 2.0 gpm of cooling water per linear foot of the cooling belt conveyor  10 . In another embodiment, the cooling belt conveyor  10  utilizes about 1.2 to about 1.8 gpm of cooling water per linear foot of the cooling belt conveyor  10 .  
         [0027]    The reduction station  15 , in the embodiment shown in FIG. 1, has a first stage squeeze roller  60 , a second stage squeeze roller  65 , a first support roller  70 , and a second support roller  75 . The squeeze rollers  60 ,  65  are located above the cooling belt  30 . The contact surfaces of the squeeze rollers  60 ,  65  are stainless steel, TEFLON®, or another material known in the art as possessing good product release characteristics. The support rollers  70 ,  75  are located below the cooling belt  30  and their corresponding squeeze rollers  60 ,  65 . The support rollers  70 ,  75  support the cooling belt  30 .  
         [0028]    In the embodiment shown in FIG. 3, the reduction station  15  is located on a squeeze belt conveyor  80  and has a first stage squeeze roller  60 , a second stage squeeze roller  65 , and a low-friction board  85 . The squeeze rollers  60 ,  65  are located above the squeeze belt  90  and the low-friction board  85  is located below the squeeze belt  90 . The low-friction board  85  supports the squeeze belt  90 . The squeeze belt  90  is stainless steel, TEFLON®, or another material known in the art as possessing good product release characteristics. The squeeze belt  90  travels about conveyor wheels  35 .  
         [0029]    In one embodiment, whether the reduction station  15  is located on the cooling belt conveyor  10  or on the squeeze belt conveyor  80 , the reduction station  15  includes only one squeeze roller  60 . In other embodiments, the reduction station  15  has more than two squeeze rollers  60 ,  65 . Also, there may be more than or less than two support rollers  70  per reduction station  15 . Furthermore, in other embodiments, the low-friction board  85  may be substituted for support rollers  70 ,  75 , or vice versa.  
         [0030]    As shown in FIG. 3, in one embodiment, the reduction station  15  is separate from the cooling belt conveyor  10 . Specifically, the squeeze belt conveyor  80  has a reduction station  15  and is installed in a horizontal configuration, terminating above the cooling belt conveyor  10 . In the embodiment shown in FIG. 4, the squeeze belt conveyor  80  is installed in an inclined manner, sloping up from the orifice  26  of the hopper  25  to the cooling belt conveyor  10 . In another embodiment, the squeeze belt conveyor  80  is installed in an inclined manner sloping down from the orifice  26  of the hopper  25  to the cooling belt conveyor  10   
         [0031]    Operation of the invention will now be explained by referring to FIGS. 1, 2 and  5 . This explanation is equally applicable to the embodiments illustrated in FIGS. 3 and 4, except the product streams  27  in FIGS. 3 and 4 are reduced on the squeeze belt conveyors  80  before being routed to the cooling belt conveyors  10 . FIG. 5 a  is a block diagram showing the steps of a method for increasing the surface area contact between a product stream  27  and a conveyor belt.  
         [0032]    Referring to FIGS. 1, 2 and  5 , a product stream  27 , the product being a fully dehydrated molasses-based feed supplement or other similar animal feed product, exits the orifice  26  of the hopper  25  onto the cooling belt  30  as an unreduced product stream  95  (block  200  in FIG. 5 a ). As shown in FIGS. 1 and 2, the height and width of the unreduced product stream  95  are approximately equal to the dimensions of the orifice  26 .  
         [0033]    In one embodiment of the invention, the height of the unreduced product stream  95  is approximately 2.0 to approximately 6.0 inches and the width is approximately 1.0 to approximately 12.0 inches. In one embodiment, the height of the unreduced product stream  95  is approximately 1.25 to approximately 1.50 inches and the width is approximately 4.0 to approximately 4.5 inches. In other embodiments, the height and width of the unreduced product stream  95  may be other sizes.  
         [0034]    The unreduced product stream  95  is carried along the cooling belt  30  to the reduction station  15  (block  210  in FIG. 5 a ). The reduction station  15  converts the unreduced product stream  95  into a fully reduced product stream  100  by decreasing the height of the product stream  27  and increasing the width of the product stream  27  (block  220  in FIG. 5 a ).  
         [0035]    In one embodiment of the invention, the reduction station  15  will have decreased the height of the product stream  27  by about 10 to about 98 percent or more. In another embodiment, the reduction station  15  will have decreased the height of the product stream  27  by about 25 to about 75 percent.  
         [0036]    In one embodiment of the invention, the reduction station  15  will have increased the width of the product stream  27  by about 10 to about 500 percent. In another embodiment, the reduction station  15  will have increased the width of the product stream  27  by about 50 to about 200 percent.  
         [0037]    In one embodiment of the invention, the height of the fully reduced product stream  100  is approximately 0.25 to approximately 3.0 inches and the width is approximately 2.0 to approximately 24.0 inches. In one embodiment, the height of the fully reduced product stream  100  is approximately 0.5 to approximately 0.75 and the width is approximately 8.0 to approximately 9.0 inches. In other embodiments, the height and width of the fully reduced product stream  100  may be other sizes.  
         [0038]    In the embodiment illustrated in FIGS. 1 and 2, the reduction station  15  converts the unreduced product stream  95  into the fully reduced product stream  100  as follows. As the unreduced product stream  95  reaches the reduction station  15 , the unreduced product stream  95  is drawn between the rotating first stage squeeze roller  60  and the traveling cooling belt  30 . The height of the unreduced product stream  95  is reduced to the height of the partially reduced product stream  105  (see FIG. 1). The width of the unreduced product stream  95  is increased to the width of the partially reduced product stream  105  (see FIG. 2).  
         [0039]    The partially reduced product stream  105  is carried along the cooling belt  30  to the rotating second stage squeeze roller  65 . The partially reduced product stream  105  is drawn between the rotating second stage squeeze roller  65  and the traveling cooling belt  30 . The height of the partially reduced product stream  105  is reduced to the height of the fully reduced product stream  100  (see FIG. 1). The width of the partially reduced product stream  105  is increased to the width of the fully reduced product stream  100  (see FIG. 2). The cooling belt  30  carries the fully reduced product stream  100  from the reduction station  15  (block  230  in FIG. 5 a ).  
         [0040]    In one embodiment, the width of the fully reduced product stream  100  is now nearly equivalent to the width of the cooling belt  30 . As a result, the heat transfer rate from the product stream  27  to the cooling belt  30  is maximized because the contact area between the product stream  27  and the cooling belt  30  is maximized and because the surface area to volume ratio of the product stream  27  is maximized. Thus, the temperature of the product stream  27  can be quickly reduced, preventing further degradation of the product.  
         [0041]    Upon exiting the reduction station  15 , the fully reduced product stream  100  travels along the cooling belt  30  to a product barrel  20  or form. Once a barrel  20  or form is filled with product, the barrel  20  or form is taken to a storage area where the product is allowed to harden.  
         [0042]    The space between each squeeze roller  60 ,  65  and the cooling belt  30  or squeeze belt  90 , as the case may be, can be adjusted via a thickness adjustor  110  as shown in FIG. 3. Thus, the rate of heat transfer from a product stream  27  to a cooling belt  30  may be controlled by adjusting the thickness adjustor  110  to modify the width of the product stream  27  as it leaves the reduction station  15 .  
         [0043]    In one embodiment, the axle  115  of a squeeze roller  60 ,  65  is supported on each end by a thickness adjustor  110 . The thickness adjustor  110  is slidably mounted on a roller frame  120 . The thickness adjustor  110  has one or more slots  125  that slidably engage with bolts  130  that protrude through the slots  125  from the side of the roller frame  120 . The space between a squeeze roller  60 ,  65  and a belt  30 ,  90  may be increased by moving the roller&#39;s thickness adjustors  110  up along their roller frames  120 . Similarly, the space between a squeeze roller  60 ,  65  and a belt  30 ,  90  may be decreased by moving the roller&#39;s thickness adjustors  110  down along their roller frames  120 . In either case, the bolts  130  are then tightened to secure the thickness adjustors  110  in place.  
         [0044]    In one embodiment, as shown in FIG. 4, the thickness adjustors  110  are automated in that they are moved along a roller frame  120  by a motor  131 . In one embodiment, the motor  131  turns a shaft  132  that turns a worm gear  133  that meshes with a gear rack  134 . As the worm gear  133  rotates against the gear rack  133 , the thickness adjustor  110  is caused to translate along the roller frame  120 . In other embodiments, other gear configurations are utilized to allow the motor  131  to translate the thickness adjustor  110 . In still other embodiments, the thickness adjustor  110  is translated along the roller frame  120  via a hydraulic piston.  
         [0045]    As indicated in FIG. 4, in one embodiment, a temperature sensor  134  will be located near the end of the cooling belt conveyor  10 . In other embodiments, the temperature sensor  134  will be located in other locations along the cooling belt conveyor  10  or the squeeze belt conveyor  80 .  
         [0046]    As outlined in FIG. 5 b , in one embodiment, a temperature sensor  134  reads the temperature of the product stream  27  at some point before the product stream  27  enters the barrel  20  (block  300 ). The temperature of the product stream  27  is sent to a processor  135  (block  310 ). The processor  135  compares the temperature of the product stream  27  to an optimal temperature range stored in a memory  136  (block  320 ).  
         [0047]    As previously explained in this specification, if the product stream  27  is insufficiently cooled, significant thermal degradation of the product may occur. The temperature above which significant thermal degradation will occur is called the thermal degradation temperature. Alternatively, if the product stream  27  is excessively cooled, it will lose its workability and will be unable to conform to the barrel  20 . The temperature below which workability is lost is the workability temperature. Consequently, the optimal temperature range is a temperature range where the product stream  27  is warm enough to readily conform to the barrel  20  (i.e., above the workability temperature) but not so warm that unacceptable thermal degradation will occur (i.e., below the thermal degradation temperature). The optimal temperature range may vary from day to day depending on the chemical makeup of the molasses being used and the ambient temperature.  
         [0048]    If the temperature of the product stream  27  is greater than the thermal degradation temperature, the processor  135  will signal the motor  131  to decrease the clearance between the squeeze roller  60  and the belt  30 ,  90  (block  330   a ). This will increase the surface contact between the cooling belt  30  and the product stream  27  to lower the temperature of the product stream  27 .  
         [0049]    If the temperature of the product stream  27  is less than the workability temperature, the processor  135  will signal the motor  131  to increase the clearance between the squeeze roller  60  and the belt  30 ,  90  (block  330   b ). This will decrease the surface contact between the cooling belt  30  and the product stream  27  to raise the temperature of the product stream  27 .  
         [0050]    Once the product stream  27  has had time to react to the adjustment and its temperature has stabilized, the temperature sensor  134  will take another temperature reading. If the new temperature reading is still not within the optimum temperature range, the processor  135  will again signal the motor  131  to adjust the thickness adjustors  110  as necessary.  
         [0051]    In another embodiment, where a processor  135  and a memory  136  are not available, an operator uses a temperature sensing device to read the temperature of the product stream  27  at some point before the product stream  27  enters the barrel  20 . The operator compares the temperature reading to an optimal temperature range. If the temperature reading is greater than the thermal degradation temperature, the operator adjusts the thickness adjustors  110 , either manually or via the motor  131 , to decrease the clearance between the squeeze roller  60  and the belt  30 ,  90 . This will increase the surface contact between the cooling belt  30  and the product stream  27  to lower the temperature of the product stream  27 .  
         [0052]    If the temperature reading is less than the workability temperature, the operator adjusts the thickness adjustors  110 , either manually or via the motor  131 , to increase the clearance between the squeeze roller  60  and the belt  30 ,  90 . This will decrease the surface contact between the cooling belt  30  and the product stream  27  to raise the temperature of the product stream  27 .  
         [0053]    Once the product stream  27  has had time to react to the adjustment and its temperature has stabilized, the operator will take another temperature reading. If the new temperature reading is still not within the optimum temperature range, the operator will again adjust the thickness adjustors  110  as necessary.  
         [0054]    As illustrated in FIG. 6, to further enhance the removal of heat from a product stream  27 , the aforementioned embodiments may have one or more squeeze rollers  60 ,  65  that are chilled squeeze rollers  140 .  
         [0055]    As shown in FIG. 6, the supply piping  142  and return piping  145  connect to the ends of each axle  115 . Each axle  115  is hollow and serves as a conduit for a cooling medium to enter or exit the chilled squeeze rollers  140 . Candidates for a cooling medium include, but are not limited to, ground water, chilled water, CFCs, HFCs, HCFCs, and ammonia.  
         [0056]    The cooling medium flows through the supply piping  142 , into a chilled squeeze roller  140 , and into the return piping  145 . As the cooling medium flows through a chilled squeeze roller  140 , the cooling medium absorbs heat that transfers from the product stream  27  through the surface of the chilled squeeze roller  140 .  
         [0057]    Each piping connection to the axle  115  of a chilled squeeze roller  140  has a flexible pipe element  150 . The flexible pipe elements  150  allow the chilled squeeze roller  140  to be raised or lowered on its thickness adjustors  110  and prevents vibration from being transmitted from the chilled squeeze roller  140  to the piping  142 ,  145 .  
         [0058]    The amount and rate of heat transfer from a product stream  27  may vary depending on several different variables, such as the material of the cooling belt  30 , the temperature and flow rate of the water sprayed against the cooling belt  30 , the travel speed of the cooling belt  30 , the depth of the product stream  27 , the amount of surface contact between the cooling belt  30  and the fully reduced product stream  100 , and the composition of the product stream  27 .  
         [0059]    As shown in FIG. 4, in one embodiment of the invention, an unreduced product stream  95  of fully dehydrated molasses-based feed supplement exits the orifice  26  of the hopper  25  onto an inclined squeeze belt conveyor  80 . The unreduced product stream  95  has a height of 1.25 to 1.50 inches and a width of 4.0 to 4.5 inches. The unreduced product stream  95  travels up the squeeze belt conveyor  80  where it enters a reduction station  15  having a single squeeze roller  60 . In other embodiments, the reduction station  15  will have two or more squeeze rollers  60 .  
         [0060]    The product stream exits the reduction station  15  as a fully reduced product stream  100  having a height of 0.5 to 0.75 inch and a width of 8.0 to 9.0 inches. The fully reduced product stream  100  travels from the squeeze belt conveyor  80  onto the cooling belt  30 .  
         [0061]    The cooling belt conveyor  10  is approximately 50 feet long and has a stainless steel cooling belt  30  that travels at approximately 60 feet per minute. A VFD 44 allows the cooling belt  30  to travel at lower or higher speeds. Ground water having a temperature of approximately 58 to 62 degrees Fahrenheit is sprayed against the bottom of the cooling belt  30 . By the time the product stream  27  has traveled from the orifice  26  of the hopper  25  to the product barrel  20 , the product stream will have experienced a temperature decrease of approximately 8.0 to approximately 12.0 degrees Fahrenheit.  
         [0062]    Although the invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.