Abstract:
A wastewater separation system for separating waste from water includes an inlet, a hydrocyclone, a decanter, and a recirculating means. The hydrocyclone receives a first amount of wastewater from the inlet and centrifugally processes the wastewater in order to remove at least some of the waste from the wastewater in order to expel treated water and a second amount of wastewater. The treated water exits the system. The decanter is coupled to the hydrocyclone for accepting the second amount of wastewater in order to separate the second amount of wastewater into a collection of waste and a third amount of wastewater. The recirculating means recirculates the third amount of wastewater back to the hydrocyclone for reprocessing.

Description:
FIELD 
       [0001]    The technology described herein relates to a water treatment system, and more particularly to a system for separating fats, oils, and grease from wastewater. 
       BACKGROUND 
       [0002]    Many industries generate wastewater that predominantly includes fats, oils, and grease. Food and manufacturing industries are examples, with wastewater coming from such operations as dishwashing in a kitchen. The fats, oils, and grease within the wastewater can clog sewers. For example, approximately 30% of all clogs in the sewer are from fats, oils, and grease. The existing processes are not sufficiently effective at processing the wastewater and removing the fats, oils, and grease. 
         [0003]    Hydrocyclones have been used to separate oil from water in industries such as the oil industry. In particular, they have been used on oil rigs where water can mix with the oil. These hydrocyclones are typically large and multiple hydrocyclones are used in series in order to separate water from oil. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is a flow diagram depicting an example wastewater separation system according to the invention; 
           [0005]      FIG. 2  is a perspective view of a hydrocyclone that is utilized with the wastewater separation system of according to the invention; 
           [0006]      FIG. 3  is a top view of the hydrocyclone of  FIG. 2 ; 
           [0007]      FIG. 4  is a cross-sectional side view of the hydrocyclone of  FIG. 2 ; 
           [0008]      FIG. 5  is a cross-sectional front view of the hydrocyclone of  FIG. 2 ; 
           [0009]      FIG. 6  is an enlarged detail view of a portion “v” of the hydrocyclone of  FIG. 4 ; 
           [0010]      FIG. 7  is a flow diagram detailing the steps of processing wastewater within the separation system of  FIG. 1 ; 
           [0011]      FIG. 8  is another flow diagram detailing the steps of processing wastewater within the separation system of  FIG. 1 ; 
           [0012]      FIG. 9  depicts an image of an example hydrocyclone; 
           [0013]      FIG. 10  depicts an image of another example hydrocyclone; 
           [0014]      FIG. 11  depicts an image of an inflow chamber segment of an example hydrocyclone; 
           [0015]      FIG. 12  depicts a perspective view of an inlet segment of the hydrocyclone; 
           [0016]      FIG. 13  depicts a side view of an inlet segment; 
           [0017]      FIG. 14  depicts a top view of an inlet segment; 
           [0018]      FIG. 15  depicts a cross-sectional view of one example of a funnel of the hydrocyclone; and 
           [0019]      FIG. 16  depicts a front view of another example funnel of the hydrocyclone. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    The wastewater separation system according to the invention utilizes an example hydrocyclone and an example method as described herein. The removal of oils, grease, and fats from wastewater is a process that many companies encounter every day. In processes such as dishwashing in kitchens, larger waste particles are captured by grates or filters that are positioned in sinks. Grease traps are used to capture oils, greases and fats, and grease traps must be regularly cleaned out in order to effectively remove waste from water. Most businesses do not clean grease traps often enough. In addition, grease traps are not always effective in capturing all the waste. As a result, waste enters the waste water system and causes issues, such as clogging. The example wastewater separation system described herein provides a means for improving the treatment of wastewater so that less waste enters the wastewater or sewer system. 
         [0021]    The example system, as described in connection with the flow diagrams of  FIGS. 1, 7 and 8 , is configured to remove undesired fats, oils, and grease from wastewater by passing the wastewater through a hydrocyclone and a decanter. An example hydrocyclone is shown in  FIGS. 2-6 and 9-15 . The example system permits for the 2 stage separation of relevant portions of the wastewater. Hydrocyclones can be used to separate waste from water with a high level of efficiency, such as approximately 90%, 95% or 90-95%. The hydrocyclone includes a portion that is configured to efficiently and effectively separate the fats, oils, and grease from the wastewater. These and other unique features of the system are discussed below and illustrated in the accompanying drawings. 
         [0022]    The system of the present application includes a hydrocyclone that is configured to receive wastewater through an inlet on the hydrocyclone. As wastewater passes through the hydrocyclone, it is subjected to centrifugal forces which act to separate fluids and substances of varied density. A decanter is configured to receive wastewater from the hydrocyclone and assists in further separating the fats, oils, and greases from the water utilizing gravitational forces. Once separated, the fats, oils, and greases may be hauled away and the water may be sent to the sewer or waste water treatment system for further treatment. By pre-processing the wastewater to eliminate the fats, oils, and greases, the sewer will be subjected to less clogging. In one example, the wastewater separation system may also include a filter that is positioned before the hydrocyclone. The filter is used for pre-filtration to filter particles and other substances from the waste water. 
         [0023]    Referring now to the figures,  FIG. 1  is a flow chart showing the overall operation of the example waste water separation system  101 . As discussed above, system  101  includes a hydrocyclone  103 , a filter  104 , and a decanter  105  for the processing of selected wastewater prior to entrance through the municipal sewer system for further treatment. System  101  is configured to separate fats, oils, and greases, collectively referred to as “FOGs,” from the wastewater to reduce their presence within the municipal sewer system. This should eventually result in fewer clogs within the sewer system. Resultant oils may be separated away and processed via conventional methods (i.e. recycling or disposal). The hydrocyclone  103  will be described in greater detail in  FIGS. 2-6 and 9-15 . The system  101  accepts wastewater from a facility. The wastewater travels first through a filter  104 . The filter  104  is configured to remove small food particles that may disrupt separation within the hydrocyclone  103 . Wastewater exits the filter  104  and enters the hydrocyclone  103 . Some of the water exits the hydrocyclone  103  as treated water. The treated water enters the sewer system. The remainder of the wastewater enters the decanter  105 . The decanter  105  separates waste from the water and FOGs are removed from the decanter  105  while the remaining wastewater returns to the beginning of the system to be reprocessed. Filter  104  is shown as being included in the system  101 , but is optional. In cases where pre-filtration is not needed, it is not needed in order for the system to operate properly. 
         [0024]      FIGS. 2-6 and 9-15  illustrate various views of the hydrocyclone  103 . The hydrocyclone  103  has an elongated tubular body configured to receive pressurized fluid through an inlet and subject that fluid to centrifugal forces in an effort to separate the various liquids elements that have different densities. Fluid in the form of wastewater that contains FOGs enters the hydrocyclone  103  via inlet  107  and is routed up and around conical portion  109 . Fluid leaves hydrocyclone  103  via outlet  111 . The fluid that enters the hydrocyclone  103  is pressurized utilizing a pump or other device. The outlet  111 , along with separate valves and other devices permits for the pressure of the fluid within the hydrocyclone  103  to be regulated. Fluid in the hydrocyclone passes over the conical portion  109  and is fed tangentially into an inner tube  113  as a result of the internal pressure of the fluid. As the pressurized fluid enters inner tube  113 , it gains momentum and enters conical portion  109  where the length and angle of the conical portion  109  is selectively chosen to adequately separate water from FOGs waste. Treated water then passes downward through port  115  and proceeds onto the municipal sewer system. Other wastewater that includes FOGs escapes through port  117  and directed to the decanter  105 . An opening for the use of an optional pressure gauge is also provided. The hydrocyclone  103  also includes a relief port  119  that permits fluid to exit the hydrocyclone in the event that pressure exceeds an allowable limit. 
         [0025]    The decanter  105  is a vessel that is used to hold a fluid and allow gravitational forces to separate the elements within the fluid. Typically this could be seen in a vessel in which a wide body for the fluid is combined with a narrower neck portion. However the exact shape and size of the decanter  105  is able to vary depending on the specific circumstances and use. The wastewater that leaves port  117  is fairly cleared of FOGs and may have a ratio, for example, of as little as 10% FOGs and 90% water. The decanter  105  acts as mechanism for secondary processing of the wastewater fluid after wastewater has exited the hydrocyclone  103 . The decanter  105  takes waste from a top end of the hydrocyclone and assists in separating any remaining water from the FOGs waste. Water from decanter  105  is recycled back into a wastewater tank and may be re-processed by one or more hydrocyclones  103  within the system  101 . Over time, the various FOGs within the water are separated and removed, allowing the wastewater to be sent for processing in the municipal sewer systems. Any oil or FOGs removed may be treated and recycled, destroyed, or disposed of according to standard processes. 
         [0026]    It should be noted that the decanter is optional. It may be needed in some systems and not in others. 
         [0027]    Referring now to  FIG. 7 , a flow diagram illustrates the steps used to treat the wastewater according to the system  101 . In the first step  201 , wastewater is routed to the system. In the next step  203 , wastewater is pumped to the hydrocyclone  103 . In the next step  205 , wastewater is sorted utilizing the hydrocyclone  103 . Some of the treated water exits the hydrocyclone  103  into the sewer system in step  209 . The remaining wastewater enters a decanter to finalize separation of FOGs and water in step  207 . 
         [0028]    The decanter  105  allows water to separate from the waste using gravity. The water settles because it is heavier than the FOGs. The FOGs float on the water. The decanter  105  is similar to existing grease traps in that it helps to separate the FOGs from any water. After the FOGs have separated from the wastewater, the waste water is circulated back to the hydrocyclone  103  for reprocessing while the FOGs are stored in a grease trap. 
         [0029]      FIG. 8  depicts a more detailed flow diagram of the wastewater separation system. Wastewater enters the system through a valve under normal pressure and wastewater is permitted to collect in a collection tank E- 1 . Once the tank hits a level of fullness, the wastewater is pumped utilizing a pump E- 4  through a filter E- 5  in order to separate particulates from the water, since particulates may clog the hydrocyclone. The filter also helps to unify the liquid so that the greases and oils are suspended in the liquid. The fluid is then returned to the tank E- 1 . Fluids may be filtered more than once, if deemed necessary. Fluid is then pumped to the hydrocyclone E- 2  utilizing the pump E- 4 . 
         [0030]    In the hydrocyclone E- 2 , fluid is circulated circumferentially in order to drive FOGs and some water upwardly to exit the hydrocyclone E- 2 . Treated water exits through a lower end of the hydrocyclone E- 2 . Untreated water enters the hydrocyclone with about 1% waste. The treated water has most of the oil and greases removed from the water such that between approximately 0.1% and 0.05% of grease and oils is mixed in with the water, which is a separation efficiency of 90% and 95%, respectively. 
         [0031]    This water is considered clean enough to enter the sewer system and is, thus, expelled to the sewer system. The wastewater that exited the top end of the hydrocyclone travels to the decanter E- 3 , where water is permitted to settle from the FOGs. Approximately 90% of the FOGs present in the wastewater exit through the top end of the hydrocyclone and enter the decanter E- 3 . The decanter includes separating media that helps to separate the FOGs from the water. The FOGs exit through the top of the decanter E- 3  and are disposed of The bottom layer of water exits the decanter and is returned to the tank E- 1  for reprocessing. 
         [0032]    If pressure in the tank E- 1  becomes too high and exceeds a predetermined limit, a relief valve is coupled to the tank that permits some of the contents of the tank to be released from the tank until an acceptable pressure is reached. The hydrocyclone valve also has a relief valve that permits fluid to exit the hydrocyclone E- 2  in the event pressure in the hydrocyclone exceeds a predetermined limit. 
         [0033]    In operation, wastewater containing FOGs is routed  201  to system  101  for treatment and processing. System  101  is located prior to entry of the wastewater into the municipal sewer system. The wastewater passes through a pump  203  where it is pressurized and directed into hydrocyclone  103 . The pressure is regulated between inlet  107  and outlet  111  through the use of one or more devices and valves. The wastewater enters inner tube  103  and gains momentum for sorting  205  of the FOGs within conical portion  109 . Separated water is permitted to leave  209  hydrocyclone from a first port while water still containing FOGs is exited via a second port where it is passed to a decanter to finalize  207  the separation of FOGs from the water. 
         [0034]    Hydrocyclones are known, as discussed above in the background section. A hydrocyclone is a simple centrifuge that amplifies centrifugal force to cause fluids of different densities to separate from one another. The example hydrocyclone, as shown in  FIGS. 9-15 , has features designed to work more advantageously in removing waste FOGs from water. 
         [0035]    Example hydrocyclones  10  are shown in  FIGS. 9-11  and comprise three separate parts or segments that are constructed using known fabrication techniques and materials. The hydrocyclone segments include an inflow chamber  12 , an inlet  14 , and a funnel  16 . 
         [0036]    The inflow chamber  12  is the segment where wastewater enters. It is designed to fit nominal piping, although other sizes and types of piping may also be utilized. The inflow chamber  12  is designed to gauge and regulate the inflow pressure of the wastewater for optimal hydrocyclone  10  separation. The inflow chamber  12  is shown best in  FIGS. 9-11  and is a feed and overflow chamber that surrounds the inlet  14  and the upper and middle sections of the funnel  16 . The inflow chamber  12  has an inlet flow connection  18  on a side thereof, an outlet flow connection  20  on a top surface thereof, a relief valve connection  22  on a side thereof, and a pressure gauge connection  24  on a side thereof. The inflow chamber  12  is tubular and pipe shaped, with a closed upper and lower end. The inlet  14  is surrounded by the inflow chamber  12 . 
         [0037]    The inlet  14  is positioned in the inflow chamber  12 . In the example shown, it includes a spiral pathway  26  that generates a spiral flow down the length of the device  10 . The inlet is shown in greater detail in  FIGS. 12-14 . The inlet  14  has an opening  30  in which wastewater flows from the inflow chamber  12 . This opening  30  connects to the spiral pathway  26 , which is a downward pitched spiral channel or passageway that is designed to move the wastewater flow into a sloping radial trajectory as it enters the funnel section  16  of the hydrocyclone. The inlet  14  segment has a small overflow orifice  34 , from which the untreated-fraction of the hydrocyclone separation is removed from the top of the device  10 . 
         [0038]    The inlet  14  is a member that seats inside the top end of the funnel  16 . The inlet  14  propels inlet fluid flow down the funnel  16 . The inlet member  14  is interference fitted into the top of the funnel  16 . It can also be welded in place. The inlet  14  guides the inflow into a swirling pattern with a groove channel  26 . The inlet  14  controls the amount of wastewater that may exit from the top of the inlet  14  by varying the size of the outlet hole  34 . 
         [0039]    The funnel  16  is the segment in which wastewater is separated into two streams of treated water and untreated water via centrifugal force. The funnel  16  has a series of adjoined gradient channels. The first is a short channel that has a steeper pitch. The second is a long channel with a shallower pitch. The wastewater has a spiral flow trajectory that was generated from the spiral  26  pathway in the inlet  14 . This spiral flow continues into the funnel  16  to produce fluid-fluid separation. The funnel  16  has an underflow orifice from which the treated water flows from the bottom of the hydrocyclone device. The funnel  16  is typically long and narrow. It has three sections that may be machined from a single piece of material, such as milled from carbon steel. 
         [0040]    The sections of the funnel  16  are shown best in  FIGS. 14 and 15  and include an upper section I, a middle section II, and a lower section III. The upper section is a straight pipe, the middle section is a steep angled funnel, and the lower section is a shallow angled funnel. 
         [0041]    The hydrocyclone is driven by centrifugal force and pressurized feed of the waste stream. Centrifugal forces are created within the hydrocyclone  10  by the effects of both radial fluid flow and the specific dimensions of the funnel segment  16 , among other reasons. The centrifugal forces along with the dimensions of the hydrocyclone  10  are responsible for the separation efficiency of the device. The size of the hydrocyclone  10  can vary depending upon the particular application. In one example, the hydrocyclone  10  may be about 36 inches long. This size hydrocyclone  10  could handle most restaurant waste flows and could handle between 8 and 10 gpm of waste. If the application were a chicken factory, the size would be larger in order to accommodate a greater amount of waste. 
         [0042]    While the example inlet  14  is shown having a spiral passageway, the configuration of the passageway could vary from this design. The overall design is a function of the waste stream at issue and the size of the hydrocyclone  10 . 
         [0043]    A hydrocyclone  10  that is about 36 inches long is typically utilized for lower wastewater flow, such as, for example, less than 10 gpm. The example hydrocyclone  10  is fully scalable depending upon the application. The hydrocyclone  10  can be design taking into account specific geometries of the funnel  16 , a specific design for the spiral or other passageway in the inlet  14 , as well as the overall design of the inlet  14 , which is the tube that surrounds the top of the funnel  16 . 
         [0044]    In one example hydrocyclone  10 , the top diameter Dc is about 1 inch and the top inflow diameter Di is about 0.25 inches. The length of the top section Lcycl is about 0.5 inches, the length of the first conical section Lc is about 4.75 inches, and the length of the second conical section Lb is about 18 inches. The pitch of the first conical section Alpha is about 3 degrees. The pitch of the second conical section Beta is about 0.25 degrees. The bottom outlet diameter Du is about 0.33 inches and the top outlet diameter Do is about 0.01 inches. 
         [0045]    Examples of materials that may be utilized for the construction of the hydrocyclone  10  include metals, such as steel or stainless steel, polymer plastics, nylons, composite materials, such as carbon fiber, other materials, or a combination of any of these materials. 
         [0046]    Although only one hydrocyclone  10  and one decanter have been described and illustrated, it is understood that other embodiments may utilize and include a plurality of hydrocyclones and/or decanters in series or parallel to achieve the desired purity of the treated water. 
         [0047]      FIGS. 9-15  are meant for illustration purposes and are not exacting in terms of dimensions. 
         [0048]    Although municipal water treatment systems are referred to in this application, it is understood that other treatment systems may be contemplated for use post treatment with system  101 , including septic systems and the like. Additionally, system  101  may be used at any point within the treatment of wastewater in accordance with existing municipal or other water treatment systems. 
         [0049]    The term “substantially,” if used herein, is a term of estimation. 
         [0050]    While various features of the claimed invention are presented above, it should be understood that the features may be used singly or in any combination thereof. Therefore, the claimed invention is not to be limited to only the specific embodiments depicted herein. 
         [0051]    Further, it should be understood that variations and modifications may occur to those skilled in the art to which the claimed invention pertains. The embodiments described herein are exemplary of the claimed invention. The disclosure may enable those skilled in the art to make and use embodiments having alternative elements that likewise correspond to the elements of the invention recited in the claims. The intended scope of the invention may thus include other embodiments that do not differ or that insubstantially differ from the literal language of the claims. The scope of the present invention is accordingly defined as set forth in the appended claims.