Abstract:
A flush apparatus for a filter underdrain system can include a fluid connection member having a body with a first end and a second end, the first end adapted to connect to a fluid source; a top plate connected to the second end of the fluid connection member; and a bottom plate opposing the top plate and adapted to engage a top portion of an underdrain system, the bottom plate having orifices that distribute fluid to the underdrain system to transport materials through the underdrain system. A system for cleaning unwanted materials from a water or waste water treatment filter and a method of transporting unwanted materials through an underdrain system are also disclosed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/923,424, filed Jan. 3, 2014, the entire contents of which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to water or waste water filters and, in particular, to a flush apparatus for water or waste water filters. 
         [0004]    2. Description of Related Art 
         [0005]    Gravity filters are used to separate suspended solids from water. The main components of gravity filters are filtering media and underdrain blocks. Underdrain blocks are generally square, rectangular, or triangular in cross section and have a long longitudinal axis as compared to their cross section. They are attached end-to-end to form long sections called laterals, or are extruded to length, or are fabricated to length. Filter underdrain laterals are laid on the floor of the filter tank one next to the other in parallel rows to define gas and liquid flow conduits below a bed of filtering media. The filtering media is used to capture dirt and other unwanted materials from a liquid being filtered as the liquid passes through the media. The filter media can be supported by a media barrier such as a media retainer so that media will not pass into the underdrain block. 
         [0006]    The gas and liquid flow conduits make possible the collection of filtered liquid during filtration and the distribution of gas and liquid for backwash. Typically, a common main conduit (known as a “flume”) is located immediately next to or under the filter tank to collect the effluent filtered liquid from the underdrain laterals during filtration. 
         [0007]    Within the different chambers of the underdrain, debris can accumulate, normally as a result of some type of structural or operational failure. This debris can come from a number of sources. For instance, inadvertent construction debris can be introduced through the effluent piping network connected to the flume. In addition, a filter underdrain system can have a structural failure that permits granular filter media to bypass the media barrier component, allowing media to accumulate within the filter underdrain system. 
         [0008]    The removal of debris and media from the underdrain is desirable, as the debris and media can have an adverse effect on the operation of the underdrain, and as a result, adversely affect the performance of the filter. For example, debris accumulation can cause ineffective cleaning, or backwashing, of the media. Debris accumulation can also cause areas of unequal filtering rates across the length and width of the filter due to excessive pressure drop in affected areas. Further, debris can be a source for the growth of harmful bacteria. 
         [0009]    While nearly all filter underdrain systems can be physically cut open to employ flushing techniques for debris removal, it is advantageous to clean the media from the underdrain systems without altering the physical characteristics of the underdrain system. By physically cutting a hole or opening into the underdrain system, the structural strength of the underdrain system can be compromised upon repair. 
         [0010]    One option for removing debris without cutting holes or openings is to discharge filtered water into one of a number of types of effluent collection configurations, such as a flume mentioned above. If debris from within a filter underdrain system can be forced in-situ to the effluent collection area, the debris can be collected and removed from the filter underdrain system without physically altering the underdrain. 
         [0011]    Thus, it would be desirable to provide an apparatus that utilizes pressurized fluid (water and/or air) to move debris from the various chambers of the underdrain system, and to transport the debris into the filter effluent chamber for collection and removal. 
       SUMMARY OF THE INVENTION 
       [0012]    In accordance with one embodiment of the present invention, an in-situ flush apparatus for a filter underdrain system can include: a fluid connection member having a body with a first end and a second end, the first end adapted to connect to a fluid source; a top plate connected to the second end of the fluid connection member; and a bottom plate opposing the top plate and adapted to engage a top portion of an underdrain system, the bottom plate comprising orifices that distribute fluid to the underdrain system to transport materials through the underdrain system. The apparatus can also include a middle plate positioned between the top plate and the bottom plate, the middle plate includes a plurality of channels. The plurality of channels direct fluid to the orifices of the bottom plate. A seal, such as a gasket, can also be attached to a portion of the bottom plate. 
         [0013]    In certain embodiments, the fluid connection member contains valves to control the flow of water from the fluid source to each channel. The fluid connection member can also include a flowmeter to control the pressure of fluid and a pressure gauge adapted to measure the pressure of fluid. 
         [0014]    The present invention is also directed to a system for cleaning unwanted materials from a water or waste water treatment filter that includes: an underdrain system that includes an underdrain bock; a fluid source; and the in-situ flush apparatuses described above. The system can further include an effluent collection device that receives the materials transported through the underdrain block. The effluent collection device can be a flume. 
         [0015]    The system can also include a hose extending from the effluent collection device to the underdrain block. In some embodiments, the system includes a downcomer stem positioned in a top wall of the underdrain block. A hose can be used to provide additional fluid to the underdrain block through the downcomer stem. 
         [0016]    The present invention also includes a method of transporting unwanted materials through a filter underdrain system, the method includes: positioning the in-situ flush apparatuses described above onto a top portion of an underdrain system; attaching the first end of the fluid connection member to the fluid source; and distributing fluid from the fluid source out of the flush apparatus through orifices positioned in the bottom plate of the flush apparatus and into the underdrain system. The unwanted materials can be transported from the underdrain system to an effluent collection device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view of a media retainer and an underdrain of a filter underdrain system according to an embodiment of the present invention; 
           [0018]      FIG. 2  is a front cross-sectional view of a filter underdrain system according to an embodiment of the present invention; 
           [0019]      FIG. 3  is a front view of a filter with a collection flume and underdrain blocks in accordance with an embodiment of the present invention; 
           [0020]      FIG. 4  is a front cross-sectional view of a flush apparatus according to one embodiment of the of the present invention; 
           [0021]      FIG. 5  is a perspective view of a flush apparatus positioned on top of an underdrain block in accordance with one embodiment of the present invention; 
           [0022]      FIG. 6  is a bottom view of the bottom plate of a flush apparatus in accordance with one embodiment of the present invention; 
           [0023]      FIG. 7  is a bottom view of the bottom plate of a flush apparatus partially removed from an underdrain block in accordance with one embodiment of the present invention; 
           [0024]      FIG. 8  is a perspective view of a flush apparatus positioned on top of an underdrain system in accordance with another embodiment of the present invention; 
           [0025]      FIG. 9  is a front cross-sectional view of a flush apparatus illustrating the flow of fluid during flushing in accordance with one embodiment of the present invention; 
           [0026]      FIG. 10  is a perspective view of a hose and nozzle that can provide additional motive force during flushing of debris in accordance with one embodiment of the present invention; 
           [0027]      FIG. 11  is a perspective view of a downcomer stem that can be used to distribute fluid for additional motive force during flushing of debris in accordance with another embodiment of the present invention; and 
           [0028]      FIG. 12  is a perspective view of a flowmeter in accordance with one embodiment of the present invention. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0029]    For purposes of the description hereinafter, the terms “upper,” “lower,” “right,” “left,” “vertical,” “horizontal,” “top,” “bottom,” “lateral,” “longitudinal,” and derivatives thereof shall relate to the invention as it is oriented in the drawing figures. However, it is to be understood that the invention may assume alternative variations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the invention. Hence, specific dimensions and other physical characteristics related to the embodiments disclosed herein are not to be considered as limiting. 
         [0030]    Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10. 
         [0031]    In this application, the use of the singular includes the plural and plural encompasses singular, unless specifically stated otherwise. In addition, in this application, the use of “or” means “and/or” unless specifically stated otherwise, even though “and/or” may be explicitly used in certain instances. 
         [0032]    Referring to  FIG. 1 , a filter underdrain system  10  in accordance with one embodiment of the present invention can include at least one underdrain block  12 . In certain embodiments, the underdrain system  10  also includes a filter media retainer  14  that can be mounted on top of the underdrain block  12 . A layer or multiple layers of filter media (not shown) is poured on top of the filter media retainer  14 . As described above, the filter media acts to remove undesirable particles from a liquid that is being filtered through the filter underdrain system  10 . 
         [0033]    In certain embodiments, as shown in  FIG. 2 , the underdrain block  12  can have a plurality of exterior walls including a top wall  18 , a bottom wall  20 , and a pair of side walls  22  extending between the top wall  18  and the bottom wall  20 . A plurality of internal walls  24  divide the hollow interior of the underdrain block  12  into a primary horizontal chamber  26  and two secondary horizontal chambers  28  positioned on opposite sides of primary horizontal chamber  26 . Additionally, a plurality of channels  32  are provided on internal walls  24  to provide fluid communication between primary horizontal chamber  26  and secondary horizontal chambers  28 . Non-limiting examples of suitable underdrains are also described in United States Publication No. 2014/0166567 and U.S. Pat. No. 5,489,388, both of which are incorporated by reference herein in their entirety. 
         [0034]    In certain embodiments, the primary chamber  26  can be connected to an effluent collection chamber  40 , such as a flume, which, in turn, conveys the filtered liquid to a clearwell (not shown) for distribution to the consumer.  FIG. 3  illustrates a series of underdrain blocks  12  positioned in a filter  39  with an effluent collection chamber  40 . 
         [0035]    As described above, media and debris can be displaced between the filter media retainer  14  and the top wall  18  of the underdrain block  12 . Media and debris can also be displaced into the secondary chambers  28  and the primary chamber  26  of the underdrain block  12 . In order to remove the media and debris located in the secondary chambers  28 , primary chamber  26 , and between the filter media retainer  14  and the top wall  18  of the underdrain block  12 , an in-situ flush apparatus  50  can be used. As used herein, “in-situ flush apparatus” refers to an apparatus or device that can flush or displace materials from an underdrain without physically altering the structure of the underdrain block  12 . 
         [0036]    As shown in  FIG. 4 , the flush apparatus  50  can include a fluid connection member  52  having a body  54  with a first end  56  and a second end  58 , a top plate  60 , and a bottom plate  62 . In certain embodiments, the first end  56  of the fluid connection member  52  can be connected to a fluid source  64 , such as a hose, as shown in  FIG. 5 , and the second end  58  can be connected to the top plate  60 . The body  54  of the fluid connection member  52  can be formed from multiple pipes or other connections extending between the top plate  60  and a fluid source  64  and which allows fluid to flow from the fluid source  64  and into the top plate  60 . The second end  58  of the fluid connection member  52  can be inserted into the top plate  60  to form at least one connection point  68  between the second end  58  of the fluid connection member  52  and the top plate  60 . In certain embodiments, as shown in  FIG. 4 , the second end  58  of the fluid connection member  52  can be inserted into the top plate  60  to form two or more connection points  68  between the second end  58  of the fluid connection member  52  and the top plate  60 . In certain embodiments, the top plate  60  includes holes for receiving the second end  58  of the fluid connection member  52 . 
         [0037]    As indicated above, the flush apparatus  50  also includes a bottom plate  62 . The bottom plate  62  is positioned opposite the top plate  60  and can include a plurality of orifices  70  as shown in  FIGS. 6 and 7 . The orifices  70  in the bottom plate  62  allow fluid to exit the flush apparatus  50 . As such, fluid from a fluid source  64  can flow through the fluid connection member  52 , into the top plate  60 , and out through the orifices  70  of the bottom plate  62 . Referring to  FIG. 6 , the orifices  70  can be placed in different areas of the bottom plate  62 . Thus, specific orifices  70  will distribute fluid out of specific areas of the bottom plate  62 . 
         [0038]    Referring to  FIGS. 5 and 8 , the bottom plate  62  is further adapted to engage a top portion of an underdrain system  10 . In certain embodiments, the bottom plate  62  is adapted to engage the top of a filter media retainer  14 . Alternatively, the bottom plate  62  can directly engage the top wall  18  of the underdrain block  12  when a filter media retainer  14  is not used. 
         [0039]    In certain embodiments, as shown in  FIGS. 4 and 7 , a seal  72  can be attached to a portion of the bottom plate  62  without blocking the orifices  70 . The seal  72  helps form a tight engagement between the bottom plate  62  and the underdrain system  10 . In one embodiment, the seal  72  is a gasket. 
         [0040]    In certain embodiments as shown in  FIG. 4 , the flush apparatus  50  can also include a middle plate  80  positioned between the top plate  60  and the bottom plate  62 . The middle plate  80  can include a plurality of channels  82  that form a labyrinth through which fluid entering the top plate  60  can flow to the orifices  70  of the bottom plate  62 . As noted above, the second end  58  of the fluid connection member  52  can be connected to the top plate  60  at one or more connection points  68 . Each connection point  68  in the top plate  60  can be associated with a specific channel  82  that leads to designated orifices  70  in the bottom plate  62 . Thus, fluid entering a specific connection point  68  will be directed to designated orifices  70  in the bottom plate  62 .  FIG. 9  is a cross-sectional view of the flow of fluid, represented as reference letter “A”, through the second end  58  of the fluid connection member  52  and the top plate  60 , middle plate  82 , and bottom plate  62  of the flush apparatus  50 . 
         [0041]    In addition, the top plate  60 , middle plate  80 , and bottom plate  62  can be connected together using various methods. For instance, in some embodiments, the top plate  60 , middle plate  80 , and bottom plate  62  can be connected together with fasteners such as screws. Further, the top plate  60 , middle plate  80 , and bottom plate  62  can be made of the same material or different materials. In certain embodiments, the top plate  60 , middle plate  80 , and bottom plate  62  are all made of polyvinylchloride. 
         [0042]    Referring to  FIG. 4 , in certain embodiments, the fluid connection member  52  includes one or more valves  86  to control the flow of fluid entering the top plate  60 . Further, different valves  86  can control the flow of fluid through different connection points  68 . As a result, fluid can be directed to a single connection point  68  that is associated with a specific channel  82  which in turn leads to designated orifices  70  in the bottom plate  62 . This allows control over the location in the bottom plate  62  where fluid will exit and the location in the underdrain system  10  where the fluid will enter. For example, the valves  86  can be controlled so that fluid will only flow through one connection point  68  which is associated with a channel  82  that leads to orifices  70  located in the center region of the bottom plate  62 . The valves  86  can then be adjusted so that fluid will only flow through a different connection point  68  which is associated with a channel  82  that leads to orifices  70  located on the outside regions of the bottom plate  62 . The ability to control the direction of fluid through the flush apparatus  50  allows specific regions of the underdrain block  12  to be flushed as desired. 
         [0043]    As shown in  FIG. 4 , the fluid connection member  52  can include a pressure gauge  88  that can measure the pressure of fluid to each channel  82 . The fluid connection member  52  can also include a flowmeter  89 , such as a rotometer, to control the pressure of fluid to each channel  82 .  FIG. 12  illustrates a flowmeter  89  that can be used with the present invention. In certain embodiments, the flowmeter  89  can be positioned upstream from the first end  56  of the fluid connection member  52 . In such embodiments, as shown in  FIG. 12 , the flowmeter  89  can be connected between the first end  56  of the fluid connection member  52  and the fluid source  64 . The flowmeter  89  can also be positioned between the first end  56  of the fluid connection member  52  and the pressure gauge  88 . The pressure gauge  88  and flowmeter  89  help further control the flushing process. 
         [0044]    In certain embodiments, when a long underdrain lateral formed from multiple underdrain blocks  12  needs flushed, two or more flush apparatuses  50  can be used to flush media and other unwanted material from the underdrain lateral. For example, two flush apparatuses  50  can be used where one of the flush apparatuses  50  is positioned at an end of the underdrain lateral farthest away from the effluent collection chamber  40 . This provides additional motive force in the direction of the effluent collection chamber  40  to ensure the media and unwanted materials are flushed to the effluent collection chamber  40 . 
         [0045]    In certain embodiments, there is a direct opening from the effluent collection chamber  40  to the primary chamber  26  of the underdrain block  12 . In such circumstances, flexible hoses  90  can be inserted into the primary chamber  26  from the effluent collection chamber  40  with nozzles  92  pointing backward toward the effluent collection chamber  40 . The fluid released from the hose  90  can be used to provide additional motive force in the direction of the effluent collection chamber  40 .  FIG. 10  shows a portion of a hose  90  and nozzle  92  that can be inserted into the primary chamber  26  of the underdrain block  12  to provide additional motive force in the direction of the effluent collection chamber  40 . 
         [0046]    In another embodiment, as shown  FIG. 11 , a downcomer stem  96  can be positioned through the top of the underdrain system  10 . In certain embodiments, as shown in  FIG. 12 , the downcomer stem  96  is positioned through the top wall  18  of the underdrain block  12 . Alternatively, when a filter media retainer  14  is used, the downcomer stem  96  can be positioned through a filter media retainer  14  and the top wall  18  of the underdrain block  12 . A hose  90  can then be connected to the downcomer stem  96 . Fluid from the hose  90  can assist in forcing media and unwanted material to travel the length of an underdrain lateral. 
         [0047]    The present invention is also directed to a method of flushing unwanted materials from an underdrain block  12  using the flush apparatus  50  described above. The method can first include placing a flush apparatus  50  onto a top portion of an underdrain system  10  such that the bottom plate  62  of the flush apparatus  50  engages the top of the underdrain system  10  such as the top wall  18  of the underdrain block  12  or the top of a filter media retainer  14 . The flush apparatus  50  can have various sizes and shapes. In one embodiment, the flush apparatus  50  can have the same width of the underdrain block  12 . After positioning the flush apparatus  50  onto the underdrain system  10 , fluid can be distributed from a fluid source  64  to the fluid connection member  52 . Valves  86  positioned on the flush apparatus  50  can be controlled to direct the fluid to a specific connection point  68  formed between the second end  58  of the fluid connection member  52  and the top plate  60 . The fluid then flows through the channels  82  to specific orifices  70  located in a designated region of the bottom plate  62 . Fluid will flow out of these orifices  70  and into areas of the underdrain block  12  associated with the specific regions of the bottom plate  62  where the fluid will exit. In certain embodiments, the valves  86  can be adjusted so fluid enters a different connection point  68  associated with a different channel  82  and different orifices  70 , thereby directing fluid into specific and different areas of the filter media retainer  14  and/or the underdrain block  12  of the underdrain system  10 . 
         [0048]    The fluid flushes media and other unwanted material into the secondary chambers  28  of the underdrain block  12 . The media and unwanted materials are further flushed through the channels  32  provided on internal walls  24  of the underdrain block  12  and into the primary chamber  26 . The media and unwanted materials, now in the primary chamber  26 , can be flushed toward the effluent collection chamber  40 , such as a flume, for removal. 
         [0049]    While various embodiments were provided in the foregoing description, those skilled in the art may make modifications and alterations to these embodiments without departing from the scope and spirit of the invention. For example, it is to be understood that this disclosure contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment. Accordingly, the foregoing description is intended to be illustrative rather than restrictive. The invention described hereinabove is defined by the appended claims and all changes to the invention that fall within the meaning and the range of equivalency of the claims are to be embraced within their scope.