Abstract:
A waste water filtration system filters polluted waste water from various waste water sources including fire sprinkler systems and fire hydrants. The system includes a sight tube which connects to a female swivel connection on, for example, a Fire Department Connection (FDC). A flexible hose connects the sight tube to a mobile filtering system. The sight tube allows the observation of a waste water flow from the waste water source to ensure that a complete flushing has been accomplished. The filtering system includes a stainer to capture large particles, a filter to capture small particles, and a chemically selective sponge to capture, for example, oil, and destroy bacteria. The filtering system allows compliance with NFPA Standards, California State Fire Marshal&#39;s “Title 19 Regulations for maintaining fire sprinkler systems, and Federal Clean Water laws, Federal Coastal Zone laws, and local city ordinances for releasing liquids into storm drains.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to containment of stagnant, polluted, and/or contaminated liquids and in particular to containment, filtration, and discharge of the stagnant, polluted, and/or contaminated water released from sprinkler systems during periodic testing. 
     Although the water entering a sprinkler system is generally potable water, there are subsequent effects which may drastically reduce the quality of the water in such systems. This water often remains in the sprinkler system for one or more years becoming contaminated, stagnant, and stale, having a very foul odor. Black iron pipe is generally used since it is more economical than potable piping, but unfortunately black iron pipe is prone to rusting which contaminates water residing in the black iron pipe. Also, new black iron pipe has an oil coating to protect it from rusting between manufacture and installation. This oil coating also contaminates the water. 
     In addition to the effects of using black iron pipe, the water residing in fire sprinkler lines in most buildings is contaminated with pollutants including chemicals, toxins, and disease causing agents. Nitrates, poly-phosphates and other corrosive inhibitors, as well as fire suppressants and anti-freeze may be added to the sprinkler water system as well. Also, between sprinkler system flushes, the water residing in the pipes may accumulate iron, magnesium, lead, copper, nickel, and zinc. This water generally becomes toxic and contains living and dead bacteria and breakdown products from chlorination. This may result in a significant Biochemical Oxygen Demand (BOD) problem. The BOD is a measure of the amount of oxygen required for the biochemical degradation of organic material in a water sample. 
     Such sprinkler systems are common in both residential and commercial building. Because of the obvious safety issues with reliance on a sprinkler system, periodic testing of sprinkler systems is required by the National Fire Protection Association (NFPA) standards (NFPA13). Such tests generally include draining and flushing stagnant, polluted, and/or contaminated water from the sprinkler systems and generally results in the stagnant, polluted, and/or contaminated water run off into the storm drains. The sprinkler tests include a Quarterly Fire Sprinkler Test, a Quarterly Drain Test, a Yearly Flow Test, a 5-Year Fire Sprinkler Certification Test, and a Flush Test for all new fire sprinkler system installations. 
     The Quarterly Fire Sprinkler Test includes placing an intentionally broken sprinkler head at the end of a sprinkler pipe to simulate an actual fire sprinkler activation. Fire sprinklers are designed to include an inspector&#39;s test valve attached with one inch piping leading to the outside of the building. Once the inspector&#39;s test valve is opened, it detects the broken sprinkler head and simulates an actual fire sprinkler activation. The inspector attempts to confirm that the local bell for the building goes off and also that a monitoring company has received a signal indicating that the sprinkler system has been activated. Stagnant, polluted, and/or contaminated water is released during this test and generally runs off into storm drains leading to streams, lakes and beaches. 
     The Quarterly Drain Test is required by the NFPA and insurance companies and requires opening a drain valve at a sprinkler riser for a few seconds and then closing the drain valve quickly to see how quickly a pressure gauge returns to normal pressure. The Quarterly Drain Test assures that a main valve out in the street is open and has not been accidentally closed by a public works employee. Again, the stagnant, polluted, and/or contaminated water released during this test generally runs off into the storm drains leading to streams, lakes and beaches. 
     The Yearly Flow Test is required by the NFPA on public and on-site fire hydrants (hydrants on private properties). The hydrant&#39;s valve is exercised and flowed. A diffuser is connected to a 2½ inch outlet on the fire hydrant and a pilot tube is used to measure the flow in Gallons Per Minute (GPM) and residual pressure when the valve is fully open. Again, stagnant, polluted, and/or contaminated water is released during this test and generally runs off into the storm drains leading to streams, lakes and beaches. 
     The Five Year Sprinkler Certification Test is perhaps the most important of all the fire sprinkler tests because without this certification, occupancy of the building cannot be granted. A portion of the Five Year Sprinkler Test requires that a backflush test be performed. The backflush test requires that a check valve located by the Fire Department Connection (FDC) be reversed or blocked in the open position in order to perform the test. This procedure requires one to shut-off the main control valve and to remove (generally unbolt), reverse the check valve, the control valve is then opened allowing water to run freely out to the FDC outlets which is an FDC inlet during normal operation. Such backflush insures that the FDC is free and clear of any obstructions, debris or foreign objects. If an FDC is clogged by such debris, or even merely contains such debris, the debris may enter the sprinkler system and may cause damage to the fire sprinkler system and/or make the system inoperable or less effective. The FDC is normally located by the sidewalk a few feet from the storm drains. The Five Year Sprinkler Certification Test is usually witnessed by the Fire Department to confirm that the FDC is clear. When this test is performed, the stagnant, polluted, and/or contaminated water released during the test generally runs off into the storm drains leading to streams, lakes and beaches. 
     Another NFPA requirement is that all new fire sprinkler system installations must have a Flush Test performed. The fire sprinkler system receives water from a Water Department&#39;s main potable water system (or main) generally running under a street in front of the building containing the system. An underground utilities company is usually contracted to perform a Hot Tap into the main. This requires specialized equipment to cut into the main while it is still containing water under pressure and install a control valve. The underground contractor then runs underground piping to the property line. The fire sprinkler contractor takes over at the property line and continues the underground piping, installing a backflow preventor, an FDC, and a control valve. Prior to connecting into the sprinkler&#39;s riser, the Flush Test of the underground piping is required. This test is witnessed by the Fire Department. Often, the water in the underground piping is black, contains oil, metal shavings, debris, etc. This stagnant, polluted, and/or contaminated water generally is released into the storm drains leading to streams, lakes and beaches. 
     In addition to periodic testing, in the course of a tenant improvement project, the standard procedure for a Fire Sprinkler Contractor is to drain the sprinkler system. However, some trapped water remains in the lines and is later emptied into, for example, a 55 gallon drum with wheels. A serviceman dumps the water, which often includes stagnant, polluted, and/or contaminated water, to the curb which leads to the storm drains leading to streams, lakes and beaches. 
     The release of contaminated water into storm drains not only causes sickness, but sometimes even deaths in humans, animals and aquatic life. This water pollution problem, along with other industrial wastes, has contributed to rendering several recreational areas, streams, lakes and beaches completely contaminated and unsafe. 
     The “Federal Clean Water Act” requires that the fire sprinkler waste water flushed from a sprinkler system be directed to a sewer leading into a water treatment plant. Under no circumstances should fire sprinkler water containing high levels of pollutants be allowed to enter the storm drains. The illegal practice of allowing contaminated fire sprinkler water to enter the storm drains has been ongoing for decades, perhaps since fire sprinklers were first introduced to the public, in spite of stiff fines and penalties from the Water Districts. Because of the present difficulty in satisfying the Federal Clean Water Act, sprinkler system tests are still conducted which allow the polluted water to enter storm drains. 
     Although some municipalities have started requiring containment of this flushed polluted water when performing these tests, known apparatus and methods have failed. Some have suggested running hoses connected to the FDC directly to a sewer line. Unfortunately, the sewer lines are often blocks away from the FDC and this procedure would require traffic control since the sewer plates are located in the middle of the streets. Also, the fire inspectors would have to be present at the street sewer plate to witness the clear water indicating that the FDC has been flushed and cleared. 
     Another proposed method is to have a waste management disposal company collect the water and then transfer it to a water treatment plant. But to coordinate with a fire inspector and a waste management disposal company is problematic. Because of the fire department inspector&#39;s heavy workload, they are often late for these scheduled tests. The added cost to contract a waste management disposal company, and have them also wait for the inspector, would have to be passed on to the business owner and would be cost prohibitive. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention addresses the above and other needs by providing a waste water filtration system which filters polluted waste water from various waste water sources including fire sprinkler systems and fire hydrants. The system includes a sight tube which connects to a female swivel connection on, for example, a Fire Department Connection (FDC). A flexible hose connects the sight tube to a mobile filtering system. The sight tube allows the observation of a waste water flow from the waste water source to ensure that a complete flushing has been accomplished. The filtering system includes a stainer to capture large particles, a filter to capture small particles, and a chemically selective sponge to capture, for example, oil, and destroy bacteria. The filtering system allows compliance with NFPA Standards, California State Fire Marshal&#39;s “Title 19 Regulations for maintaining fire sprinkler systems, and Federal Clean Water laws, Federal Coastal Zone laws, and local city ordinances for releasing liquids into storm drains. 
     In accordance with one aspect of the invention, there is provided a feasible and cost effective system waste water filtering system including a sight tube for observing the clarity of a waste water flow, a filtering suite connected to the sight tube for receiving the waste water flow from the sight tube, and a drain hose connected to an outlet of the filtering suite for carrying the clean flow to a drain site. The filtering suite sequentially includes first, a strainer for capturing large particles in the waste water flow to create a strained flow, second, a filter for capturing small particles remaining in the strained flow to create a filtered flow, and third, a second sight tube encasing a chemically selective polymer for capturing oils in the filtered flow to create a clean flow. The filtering suite may further include a Reverse Osmosis (RO) filter at the outlet of the chemically selective polymer for capturing nitrates in the clean flow. A rod generally protrudes from the sprinkler system end of the clear sight tube connector fitting and holds a clapper in the FDC open during the backflush test. The rod is preferably a ⅜ inch all thread rod. The clear sight tube allows a fire department inspector to visually observe a waste water flow through the sight tube change from dirty to clean as the flushing of the fire sprinkler system is performed. When sufficient filtering is performed, and proper permission obtained from local authorities, the filtered waste water may be released into storm drains. Different standard fittings would be used for different applications, for example, Quarterly and Drain Tests. 
     In accordance with yet another aspect of the invention, there is provided a method for waste water filtering. The method includes: connecting a sight tube to a Fire Department Connection (FDC); connecting a first end of a hose to the sight tube; connecting a second end of the hose to a filter system, the filter system sequentially comprising a strainer, a filter, and an encased chemically selective polymer; positioning a filter system drain hose to empty into a storm drain and/or landscaping; releasing a flow of waste water from the FDC through the sight tube and hose to the filter system; observing the flow of waste water through the sight tube; continuing the flow of waste water until a clean flow is observed in the sight tube; and shutting off the flow of waste water from the FDC. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: 
         FIG. 1  depicts a waste water filtering system according to the present invention connected to a Fire Department Connection (FDC). 
         FIG. 2  depicts a second embodiment of a waste water filtering system according to the present invention connected to the Fire Department Connection (FDC). 
         FIG. 3  depicts a third embodiment of a waste water filtering system according to the present invention connected to the Fire Department Connection (FDC). 
         FIG. 4  depicts a fourth embodiment of a waste water filtering system according to the present invention connected to the Fire Department Connection (FDC). 
         FIG. 5  depicts a fifth embodiment of a waste water filtering system according to the present invention connected to the Fire Department Connection (FDC). 
         FIG. 6A  is a side view of a sight tube according to the present invention. 
         FIG. 6B  is a top view of the sight tube. 
         FIG. 6C  is an end view of the sight tube. 
         FIG. 7A  is a side view of a barbed fitting of the sight tube. 
         FIG. 7B  is an end view of the barbed fitting of the sight tube. 
         FIG. 8  is a cross-sectional view of the sight tube taken along line  8 - 8  of  FIG. 6A . 
         FIG. 9A  is a side view of an all thread rod used to hold a clapper valve open. 
         FIG. 9B  is an end view of the all thread rod used to hold the clapper valve open. 
         FIG. 10  is a side view of a strainer of a filtering suite according to the present invention. 
         FIG. 11  is a cross-sectional view of the strainer taken along line  11 - 11  of  FIG. 10 . 
         FIG. 12  is a side view of a filter of a filtering suite according to the present invention. 
         FIG. 13  is a cross-sectional view of the filter taken along line  13 - 13  of  FIG. 12 . 
         FIG. 14  is a cross-sectional view of a second sight tube encasing a chemically selective polymer. 
         FIG. 15  is a side view of a media bag filter containing the chemically selective polymer. 
         FIG. 15A  is cross-sectional view of the media bag of the media bag filter containing the chemically selective polymer taken along line  15 A- 15 A of  FIG. 15 . 
         FIG. 16A  is a front view of an all thread rod adapter for positioning the all thread rod in the FDC to hold the clapper valve open. 
         FIG. 16B  is a side view of the all thread rod adapter for all thread positioning the rod in the FDC to hold the clapper valve open. 
         FIG. 17  is the waste water filtering system mounted to a vertically expanding cart. 
         FIG. 18  is a method according to the present invention for filtering waste water released from the FDC. 
     
    
    
     Corresponding reference characters indicate corresponding components throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims. 
     A waste water filtering system according to the present invention is shown connected to a waste water source comprising a Fire Department Connection (FDC)  10  in  FIG. 1 . The waste water filtering system includes a sight tube  12 , a hose  16 , and a filtering suite  11 . The sight tube  12  is preferably attached between a first female swivel connection  14   a  attached to the FDC  13  and a second female swivel connection  14   b  attached to a sight tube end  16   a  of the hose  16 . The hose  16  is connected to a strainer  18  by a third female swivel fitting  14   c  at a strainer end  16   b  of the hose  16 . The hose  16  is preferably a two inch diameter non-kink hose and is preferably clear. A suitable material is Polyvinylchloride (PVC) and an example of a suitable hose is Master-Flex® 101CL hose made by Gates Corporation in Denver, Colo. The waste water filtering system  10  may also be applied to filtering waste water released from sources other than the FDC  13 , and in those instances a sight tube with an appropriate connection may be used, or an adapter between the sight tube  12  and the waste water source may be used. A first stand  32  supports the strainer  18  and a second stand  34  supports the filter  21 . 
     The filtering suite  11  includes the strainer  18 , a filter  21  connected to the strainer  18  by a hose  20 , and an encased chemically selective polymer  26  connected to the filter  21  by another hose  20 . The strainer  18  receives a waste water flow from the FDC  13  through the sight tube and strains the waste water flow to create a strained flow. The filter  21  receives the strained flow from the strainer  18  and filters the strained flow to create a filtered flow. The encased chemically selective polymer  26  receives the filtered flow from the filter  21  and cleans the filtered flow to create a clean flow  30  from a drain hose  27 , suitable for draining into a storm drain or into landscaping. 
     A second embodiment of a waste water filtering system  10   a  according to the present invention is shown connected to the FDC  13  in  FIG. 2 . The waste water filtering system  10   a  includes a second filter suite  11   a  with a Reverse Osmosis (RO) filter  24  connected serially between the encased chemically selective polymer  26  and the drain hose  27  to remove nitrates from the clean flow  30  The waste water filtering system  10   a  is otherwise similar to the waste water filtering system  10 . Suitable RO filters are available from Toray Membrane Inc, a supplier out of Poway, Calif. 
     A third embodiment of a waste water filtering system  10   b  according to the present invention is shown connected to the FDC  13  in  FIG. 3 . The waste water filtering system  10   b  includes a third filter suite  11   b  having a first RO filter  24   a  connected serially between the filter  21  and the encased chemically selective polymer connected  26 , and with a second RO filter  24   b  connected serially between the encased chemically selective polymer  26  and the drain hose  28 , both to remove nitrates from the filtered flow and from the clean flow  30  The waste water filtering system  10   b  is otherwise similar to the waste water filtering system  10 . 
     A fourth embodiment of a waste water filtering system  10   c  according to the present invention is shown connected to the FDC  13  in  FIG. 4 . The waste water filtering system  10   c  includes a fourth filter suite  11   c  with an RO filter  24  connected serially between the filter  21  and the encased chemically selective polymer  26  to remove nitrates from the clean flow  30  The waste water filtering system  10   c  is otherwise similar to the waste water filtering system  10 . 
     A fifth embodiment of a waste water filtering system  10   d  according to the present invention is shown connected to the FDC  13  in  FIG. 5 . The waste water filtering system  10   d  includes a fifth filter suite  11   d  with a first encased chemically selective polymer  26   a  connected serially between the sight tube  12  and the strainer  18 , and an RO filter  24  connected serially between a second encased chemically selective polymer  26   b  and the drain hose  30 . The waste water filtering system  10   d  is otherwise similar to the waste water filtering system  10 . 
     A side view of the sight tube  12  according to the present invention is shown in  FIG. 6A , a top view of the sight tube  12  is shown in  FIG. 6B , and an end view of the sight tube  12  is shown in  FIG. 6C . The sight tube  12  is preferably a clear sight tube, or at least sufficiently clear to view a flow of waste water through the sight tube  12  well enough to determine when the flow has become clean or sufficiently clean to end a test. The sight tube  12  is preferably between approximately eight inches and approximately 24 inches long and more preferably approximately twelve inches long, and preferably has an inside diameter between approximately 2¼ inches and approximately 2¾ inches and more preferably has an inside diameter of approximately 2½ inches. Barbed male fittings  22   a  and  22   b  are attached to opposite ends of a length of tubing  24  to form the sight tube  12 . An example of a suitable material for the tubing  24  is Poly Ethylene-Terephthalate Glycol (PETG) clear tubing made by Visipak in Arnold, Mo. The first fitting  22   a  connects to the first female swivel fitting  14   a  on the FDC  13  (see  FIG. 1 ), and the second fitting  22   b  connects to the second swivel fitting  14   b  on the hose  16 . Clamps  28  are tightened around the outside of the tubing  24  to cause the tubing  24  to grasp the fittings  22   a  and  22   b . The clamps  28  are preferably hose clamps. 
     A second sight tube end  12   b  resides opposite the first sight tube end  12   a  and is generally connected to the hose  16 . The first fitting  22   a  preferably includes an all thread rod fitting  23  bridging the interior of the first fitting  22   a . The rod fitting  23  is configured to attach a rod  26  (see  FIGS. 8A and 8B ) which then extends from a FDC end  12   a  of the sight tube  12 . When the sight tube  12  is connected to the FDC  13 , the rod  26  reached inside the FDC  13  and holds a clapper valve open to allow the waste water to flow from the FDC  13  into the sight tube  12 . 
     A side view of the barbed fitting  22   a  or  22   b  of the sight tube  12  is shown in  FIG. 7A  and an end view of the barbed fitting  22   a  or  22   b  is shown in  FIG. 7B . The barbed fittings  22   a  or  22   b  include male threads  30 , barbed portions  32 , and tightening features  34 . The threads  30  are preferably sized to connect to the female swivel fittings  14   a  and  14   b  and are more preferably threaded with a National Pipe Thread (NPT). The barbed portions  32  are approximately 3½ inches long. The features  34  are provided to aid in turning, or preventing turning of, the sight tube  12  when the sight tube  12  is connected to the FDC  13  or the hose  16 . The features are preferably round cylindrical projections from opposite sides of the fittings  22   a  and  22   b . An example of a suitable fitting  22   a  or  22   b  is a 2½ inch fitting available from the J. C. Gadd Company in Denver, Colo. 
     A cross-sectional view of the sight tube  12  taken along line  8 - 8  of  FIG. 6A . is shown in  FIG. 8 . The rod fitting  23  is seen residing in the barbed fitting  22   a.    
     A side view of the rod  26  according to the present invention is shown in  FIG. 9A  and an end view of the rod  26  is shown in  FIG. 9B . The rod  26  is approximately twelve inches long and approximately ¼ inches in diameter (Is this OK?). A threaded fitting may attached to the end of the rod  26  to allow extensions to be screwed onto the rod  26  for applications requiring a longer rod length L r  (for example, sixteen inches) for holding a one-way-valve open. 
     A side view of the strainer  18  of the filtering suite  11  is shown in  FIG. 10 , and a cross-sectional view of the strainer taken along line  11 - 11  of  FIG. 10  is shown in  FIG. 11 . The strainer  18  includes a removable, cleanable, and replaceable basket  48 . The waste water flow  44  enters the strainer  18 , passed into the basket  48  through ports  46 , and is strained as it flows through the basket walls  50 . The basket walls  50  preferably include orifices to capture particles greater than between approximately 50 microns and approximately 100 microns in size, and more preferably include orifices to capture particles greater than approximately 100 microns in size. A strained flow  53  is created by the strainer  18 . An example of a suitable strainer is an Eaton Model 72 made by Eaton in Eden Prairie, Minn. 
     A side view of the filter element  22  of a filtering suite  11  is shown in  FIG. 12 , and a cross-sectional view of the filter  21  taken along line  13 - 13  of  FIG. 12  is shown in  FIG. 12 . The filter  18  includes a filter bag  58  having a surface material  56  preferably selected to capture material greater than between approximately 0.5 micron and two microns in size, and more preferably selected to capture material greater than approximately one micron in size. A filtered flow  66  is created by the filter  21 . An example of a suitable filter is a Flowline filter made by Eaton in Eden Prairie, Minn. 
     A cross-sectional view of a second sight tube  26  encasing a chemically selective polymer is shown in  FIG. 13 . The sight tube  26  is similar to the sight tube  12 , but encases the chemically selective polymer preferably selected to remove oil from the filtered flow. 
     A side view of a media bag filter  70  is shown in  FIG. 15  and a cross-sectional view of the media bag filter  70  taken along line  15 A- 15 A of  FIG. 15  is shown in  FIG. 15A . The media bag filter  70  comprises a bag  74  containing the chemically selective polymer  76 . The bag  74  is preferably an open woven mesh fabric polyester. Initially, the bag  74  is filled approximately 50 percent by volume with the chemically selective polymer  76 . The chemically selective polymer  76  expands as it become saturated with water, and eventually fills the interior of the second site tube  26 . The media bag filter  70  includes a pull  72  for extracting the media bag filter  70  from the sight tube  26 . A suitable material for the bag  74  is product No. 07/950/58 made by Sefar in Monterey Park, Calif. A suitable chemically selective polymer is a Smart Sponge® material or a Smart Sponge® Plus ACX10N/55-Plus4 material made by AbTech in Scottsdale, Ariz. 
     A front view of a rod adapter  77  for positioning the rod  26  (see  FIGS. 8A and 8B ) in the FDC  13  to hold the clapper valve open is shown in  FIG. 16A  and a side view of the rod adapter  77  is shown in  FIG. 16B . The rod adapter  77  may be positioned between any sight tube, hose, etc. connected to the FDC  13 , and is held in place between the fittings. When space is not present to connect the sight tube  12  directly to the FDC  13 , the rod adapter  77  may be used with a short hose to connect the sight tube  12  to the FDC  13  through the short hose. 
     The filter suite  11  is shown residing on a vertically expanding cart  75  in  FIG. 17 . The vertically expanding cart  75  allows the filter suite  11  to be carried in a small vehicle when the cart  75  is vertically retracted. An example of a suitable cart  75  is a Model 288 Salesmaker Cart made by Ferno-Washington, INC. In Wilmington, Ohio. 
     A method according to the present invention for containing and transporting waste water is described in  FIG. 18 . The method includes: connecting a sight tube to a Fire Department Connection (FDC) at step  80 ; connecting a first end of a hose to the sight tube at step  82 ; connecting a second end of the hose to a filter suite, the filter system sequentially comprising a strainer, a filter, and an encased chemically selective polymer at step  84 ; positioning a filter system drain hose to empty into a storm drain and/or landscaping at step  86 ; releasing a flow of waste water from the FDC through the sight tube and hose to the filter system at step  88 ; observing the flow of waste water through the sight tube at step  90 ; continuing the flow of waste water until a clean flow is observed in the sight tube at step  92 ; and shutting off the flow of waste water from the FDC when a clean flow is observed at step  94 . The filter suite may further include an RO filter before or after the encased chemically selective polymer, or both before and after the encased chemically selective polymer. 
     While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.