Abstract:
An apparatus for cleaning waste collection systems of solid materials. The apparatus is capable of cleaning waste systems in two known ways. First, a pumping method uses normal and injected water flow to suspend the solids in a slurry. A submersible pump moves the slurry from a collection point up to a pressurized container where the water content of the slurry is decanted and reused as injection water while the particulate material settles to the bottom of the pressurized container. Second, a vacuum system may be used to move the slurry from the waste system to the waste container. The vacuum system creates a negative pressure differential, causing material to be pulled through a vacuum tube and into the waste container. When the container becomes substantially full of solid particles, it may be emptied at a dumpsite.

Description:
TECHNICAL FIELD  
       [0001]     The present invention relates generally to cleaning waste collection systems such as but not limited to sewers, sumps, wet wells, collection tanks, digesters, clarifiers, classifiers, etc. and in particular to cleaning and removal of solid and liquid materials therefrom.  
       BACKGROUND OF THE INVENTION  
       [0002]     Waste collection systems such as sewers, sumps, wet wells, digesters, clarifiers, classifiers, collection tanks, etc. must be cleaned periodically in order to maintain proper fluid flow and capacity. Cleaning removes sand and other deleterious materials that have infiltrated into, for example, a sewer as well as solid materials that have settled out from the normally slow moving waste slurry that varies in volume and flow rate depending on the collective amount of effluents emptied into the waste collection system over time. In order to properly clean large capacity waste collection systems such as collection tanks or the vast lengths of sewer lines in a typical city, an efficient and cost effective method of cleaning must be employed that can handle the large volume of material that must be removed from a typical waste collection system.  
         [0003]     Typically, commercial waste cleaning operations utilize a water jet router made up of a high pressure water pump feeding pressurized wash water through a hose having a cleaning head on its end. This cleaning head has water nozzles on its back face which creates a jet action resulting from the high pressure water flowing out the nozzles. The high pressure water jet action both washes the downstream waste collection system such as sewer pipe and propels the cleaning head upstream for continuous washing action of the entire length of the waste collection system such as sewer pipe being cleaned. The position of the cleaning head and its rate of forward travel is regulated by control of the hose reel integrally mounted on the washing truck.  
         [0004]     Commercial waste cleaning operations then utilize one or the other of the following two known systems and methods for moving the resulting water slurry produced from the washing action into a collection box, where the solid material is removed and disposed of in a dump or landfill.  
         [0005]     First, a second hose may be lowered into a manhole downstream of the cleaning head and is in communication with the resulting water slurry produced from the washing action. This hose is connected to a vacuum system which lifts the water slurry and all contained debris up from the bottom of the manhole into a vacuum holding tank mounted on the rear of the wash truck. Thus, the high pressure wash water brings the solid materials suspended in water to the manhole and the vacuum action picks up the waste material and deposits it into the truck-mounted holding container. When the container becomes full, the materials contained in the container are removed and disposed of, typically in a dump or landfill.  
         [0006]     Second, the operation may include a semi-submersible pump to move the water slurry produced by the washing action into the collection box. The submersible pump pushes the slurry up in a column through a slurry hose which is connected to and deposit the slurry into a pressurized collection container located on the surface. Again, when the container becomes full, the materials contained in the container are removed and disposed of, typically in a dump or landfill.  
         [0007]     Choosing between the use of a submersible pump to push the waste water slurry into the collection container or use of a vacuum to suck the slurry into the container turns largely on the conditions within the waste water system. If, for example, there is a large volume of liquid relative to solids in the slurry, vacuuming becomes very inefficient and possibly infeasible. A vacuum typically pulls out liquid much more easily than the solid material in the slurry. Thus, when a large volume of liquid is in the slurry, the vacuum may pull out only the liquid, leaving the solid material in the waste water system. A submersible pump, by contrast, requires a large volume of liquid to effectively push the slurry upward into the collection box. If very little liquid is present in the waste water system, a pump will be inefficient or may not work at all, and a vacuum is required.  
         [0008]     Existing technologies typically include a truck or other apparatus with a high pressure washer, and either a pump or vacuum for moving the waste water slurry into the collection box. Because field conditions dictate which type of technology is used, though, it is generally necessary to go to the particular waste water system to be cleaned and examine the conditions before choosing an apparatus to perform the work and delivering the apparatus to the jobsite.  
       BRIEF SUMMARY OF THE INVENTION  
       [0009]     In contrast to the prior waste cleaning apparatus and methods, the apparatus of the present invention is designed to eliminate the need to examine field conditions prior to dispatching a cleaning apparatus to the jobsite. The apparatus of the present invention has improved the overall cost and efficiency of cleaning waste water systems by using a new, novel and non-obvious combination of apparatus and techniques known in the art.  
         [0010]     The apparatus of the present invention is directed to continuous cleaning of waste collection systems such as city sewers, sumps, wet wells, digesters, clarifiers and collection tanks by high pressure water washing of the waste collection system and collection of the resulting solid materials washed therefrom. The present invention may clean any system or device that collects solids, liquids or both. The invention may comprise (1) a source of high pressure water; (2) a submersible pump capable of pumping solids and liquids; (3) a vacuum system capable of vacuuming solids and liquids; (4) a pressurized container where solid materials separate from the liquids (water) by gravity; (5) means to remove the water in the pressurized container separated from the solid materials (decanted water); and (6) means to reuse the decanted water for cleaning of the waste collection system.  
         [0011]     The high pressure water source may be a truck-mounted pump connected to a water tank or fire hydrant for its source of water. This pumping truck additionally may comprise a high pressure water hose attached to the pump and a hydraulically actuated hose reel. Mounted at the other end of the high pressure hose may be a bullet-shaped cleaning head. The cleaning head has water jet orifices on its rear face. When high pressure washing water exits through these orifices, the cleaning head is propelled forward by jet action. Rate and distance of cleaning head movement is operator controlled by the hose reel and the tethering restraint of the hose attached to the head. For example, the cleaning head and its attached hose is lowered into a manhole and then placed into the sewer pipe to be cleaned. Next, high pressure water is forced through the rear jets of the cleaning head propelling it into the sewer pipe.  
         [0012]     A source of high pressure water may also be derived from a kite. A kite is a funnel made up of flexible material such as, for example, canvass which is restrained by lines to a cable that goes back to the upstream manhole of the waste collection system, such as a sewer. When the kite is placed into a pipe of the waste collection system, water backs up behind it and reduces the flow of water through the pipe to the flow of water that can pass through the diameter of an opening in the end of the kite funnel.  
         [0013]     As head pressure builds up behind the kite, water squirts out of the funnel opening like from a high pressure fire hose. For example, at 30 feet of head pressure and a 30-inch diameter pipe reduced to a six-inch opening, there may be 400 psi water coming out of that six-inch hole at the end of the kite funnel. This water pressure is much more than can be generated by a hose/nozzle head as described above. The kite may be reeled downstream through the pipe by paying out the cable attached thereto. As the kite moves downstream through the waste collection system, the solid debris is washed toward the submergible pump or vacuum system.  
         [0014]     Yet another source of high pressure water is the Wayne ball. A Wayne ball is a ball that is approximately the same size as the inside diameter of the pipe being cleaned. This ball has concentric helical grooves cut into its surface in which water runs through the grooves and spins the ball. As the Wayne ball spins it agitates the surrounding material in the pipe and moves this material ahead of the Wayne ball toward the submergible pump or vacuum system. The Wayne ball is restrained, like the kite above, on a cable attached pivotally to the ball and allowing the ball to spin from the water flowing through the helical grooves. Water pressures obtained with a Wayne ball are similar to those pressures obtained with a kite.  
         [0015]     Pumping Waste Slurry  
         [0016]     The washing action of the high pressure water flowing through the above water pressure sources produces a slurry of waste material solids suspended in the wash water and any other liquids present in the waste collection system. If a substantial amount of liquid exists in the waste water system, a submersible pump is used to push the waste slurry created by the high pressure washing action into a pressurized collection box on the surface. The submersible pump has a greater pumping capacity in gallons per minute (“GPM”) than does the water flow even with the additional wash water. Thus, little or no flow gets past this submersible pump. The submersible pump is capable of lifting almost pure solids to the surface above the waste collection system. On the surface, a pressurized waste container is used for the collection of the slurry.  
         [0017]     The pressurized container receiving the slurry from the submersible pump works with a positive pressure to atmosphere. This allows rapid settlement to the bottom of the container of the solid materials in the slurry by means of gravity. Thus, the water contained in the slurry will float to the top of the settled solids and may be easily removed and reused and only the solids need to be transported away and disposed of at a dump.  
         [0018]     In practice, the slurry hose is in communication with the top of the pressurized container and the solid material rapidly falls out of the incoming slurry in a cascade gradient where the highest part of the solid material pile is closest to the slurry inlet. Means for removal of water separated from the slurry (“decanted water”) allows the apparatus of this invention to continuously reuse a substantial amount of the wash water for further cleaning operations. Thus, a significant advantage of the submersible pump is the conservation of water by almost total capture and subsequent reuse of both wash water and normal sewer water flow.  
         [0019]     Filtered decanted water may be used as a water source for the high pressure water pump. In addition, excess decanted water may be emptied upstream of the washing operations, thus, improving existing cleaning operations water flow. In practice, faster and better waste collection system washing operations are achieved when the water flow and volume are increased. Thus, as mentioned above, the submersible pump does not require a limited water flow as does the vacuum system, and actually benefits from increased water flow.  
         [0020]     A submersible pump is also capable of handling a much higher flow capacity than a vacuum system. For example, a vacuum system can handle only about 700 GPM of waste slurry. A pump, by contrast, can typically handle about 2,500 GPM of slurry. Thus, a submersible pump may be preferred in some situations because it can pump slurry into the collection container at a much higher rate than the vacuum can handle.  
         [0021]     Using a submersible pump with a positive pressure collection container allows for decanting slurry water back into the manhole as the solid material settles out in the collection box simultaneously with the pumping of waste slurry into the collection box. This simultaneous decanting is unavailable using a vacuum system. Thus, when using a submersible pump, the process needs to be stopped to unload the material from the collection box only when the box is completely filled with solid material. By contrast, vacuuming must cease when the collection box fills up with a combination of solid material and liquid. The more frequent stoppage using a vacuum system results in less efficient operation. Subsequently, use of a submersible pump allows for cleaning more length of pipe per time interval than does vacuuming.  
         [0022]     Vacuuming Waste Slurry  
         [0023]     A submersible pump requires a significant amount of liquid in the system to be cleaned in order to operate effectively. When there is not enough liquid to utilize the pumping system, the present invention is capable of using a vacuum system to handle drier materials in much the same way as conventional vacuum cleaning systems. As discussed above, the vacuum system is somewhat less efficient than the pumping system. However, in dry conditions it is necessary to use a vacuum rather than a pump to move waste slurry to the surface and into the collection container. Unlike any previously utilized technology, the present invention may be easily converted between pumping and vacuuming as conditions dictate.  
         [0024]     An object of the present invention is to efficiently wash sewer and other pipe lines by using either a submersible pump or vacuum technology to move waste slurry scrubbed from the pipe by high pressure water to the surface and into a collection container.  
         [0025]     A further object of the present invention is to switch quickly and easily between a submersible pump and vacuum technology to move waste slurry scrubbed from a pipe by high pressure water to the surface and into a collection container.  
         [0026]     Yet a further object of the present invention is to provide an apparatus capable of utilizing either a submersible pump or vacuum technology to move waste slurry scrubbed from a pipe by high pressure water to the surface and into a collection container, such that pipe conditions and liquid content do not need to be identified prior to dispatching the apparatus to the jobsite. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0027]      FIG. 1  is a view of an embodiment of the apparatus of the present invention wherein a submersible pump is utilized to pump the waste slurry into the waste container;  
         [0028]      FIG. 2  is a view of an embodiment of the apparatus of the present invention wherein a vacuuming system is utilized to move the waste slurry into the waste container;  
         [0029]      FIG. 3  is a rear view of a cleaning head;  
         [0030]      FIG. 4  is a view of a kite as used in the present invention;  
         [0031]      FIG. 5  is a front view of the kite of  FIG. 4 ; and  
         [0032]      FIG. 6  is an elevational view of a Wayne ball as used in the present invention. 
     
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS  
       [0033]     Referring now to  FIGS. 1 and 2 , the system of the present invention comprises a high pressure water pump assembly  10  for generating high pressure water, a high pressure water hose  12 , a hose reel  13 , a bullet-shaped cleaning head  14  for receiving high pressure water and cleaning a sewer, a submersible pump  16  for pumping a slurry of solids and liquids out of the sewer when the slurry contains a large amount of liquid, a power source  17  for the submersible pump  16 , a slurry hose  18 , a waste container  20  for receiving the pumped slurry, a decant water hose  22 , a decant water outlet  24  for releasing the water from the container, main supply water line  32 , and main supply water source  34 . The invention may be mounted to a truck  40  as seen in  FIGS. 1 and 2 , or to an immobile unit that must be towed to and from a jobsite. For consistency, the unit will be described as a truck throughout this document.  
         [0034]     The high pressure water pump assembly  10  and pump power source  17  are mounted on, for example, a truck  40  and may use the truck engine for power. The purpose of the pump assembly  10  is to pressurize water for use in washing sewer lines  42  by means of cleaning head  14  attached to and in communication with high pressure water hose  12 . The source of water for pump assembly  10  may be derived from any water source  34 , including a fire hydrant, a tank on the truck  40 , or from the sewer  42  itself.  
         [0035]     The cleaning head  14  is bullet-shaped with a front and rear face. The rear face of the cleaning head  14  has water jet outlets  15  directed backwardly. The truck  40 , high pressure water hose  12  and cleaning head  14  may be of any suitable conventional equipment. When the cleaning head  14  is lowered through a manhole  41 , and into a sewer  42 , high pressure water, such as 2000 psi is applied through the hose  12  to the cleaning head  14 . The high pressure water applied to the cleaning head  14  has several functions. First, the water sprays out of the outlets  15  and the exiting high pressure water washes the solid material from the walls of the sewer  42  and suspends the sewer pipe solid material in a slurry. Additionally, the high pressure water being applied to the cleaning head  14  moves the cleaning head  14  in a direction  43 . After cleaning the sewer  42 , the cleaning head  14  may be retrieved by retracting the high pressure water hose  12  by means of hose reel  13  as is conventional.  
         [0036]     If conditions dictate that a submersible pump  16  should be used, i.e., if a relatively high volume of liquid exists in the sewer  42 , a submersible pump  16  is provided with a capacity of more than the total flow of water being injected to the cleaning head  14  as well as any normal sewer flow. It is desirable to have a large water content in the sewer  42  for efficiently cleaning the sewer  42  by suspending the solid particles and material in the sewer  42  in a liquid slurry. The submersible pump  16  is capable of pumping a slurry having up to 80% solids.  
         [0037]     For example only, if the high pressure water pump provides a flow of 60 gallons per minute, a suitable submersible pump  16  capable of removing 2000 gallons a minute of 80% solid material is desirable for allowing the present invention to clean an operating sewer having flowing fluids therein. While any suitable submersible pump  16  may be provided, pump series  53 , sold by Garner Environmental Services, Inc., is satisfactory. Such pumps can be powered hydraulically and powered by diesel, electric motors, gasoline engines or any other available power source.  
         [0038]     The fluidized slurry from the submersible pump  16  is transmitted through the slurry hose  18  to a waste container  20 . The fluidized slurry enters the top of the container  20 , where the solids and water separate and the solids settle to the bottom of the container by gravity. If desired, baffles may be provided in the container  20  to assist in the separation. The water is then decanted from the container  20  and as the container  20  fills up, the decanted water is released from the container  20  by means of the positive pressure forcing the water through a decant water hose  22 .  
         [0039]     The waste container  20  may be either permanently affixed to the truck  40 , or may be removable therefrom. If the waste container  20  is removable, when the container  20  is substantially filled up with solid particles, it may be removed and a replacement container  20  may be rolled into place and connected to hoses  18  and  22 . The filled container  20  may then be removed to a dump site while the truck  40  remains on site and continues the cleaning operation. If the waste container  20  is permanently affixed to the truck  40 , the truck  40  must go to the dump site each time the waste container  20  becomes substantially filled up with solid materials.  
         [0040]     When the submersible pump  16  is used, the more water that flows through the cleaning head  14  and sewer  42  the better the cleaning operation. In the present system, the decanted water can be used to provide additional washing by injecting it upstream of the cleaning head  14  and pump  16 . This allows keeping the solid materials in the sewer in suspension so that they can more easily be removed by the pump  16 . The decanted water is transmitted through decant water outlet  24  to decant waterline  22  and then to a manhole  41  into the sewer  42  upstream of the cleaning head  14  for increasing the water in the sewer flow.  
         [0041]     This additional water, applied to the sewer  42  aids in more efficiently cleaning the sewer  42 , and the pump  16  has the capacity to completely remove the water in the system. Thus, the present embodiment is in effect a closed loop and the decanted water, all water injected or decanted, is utilized in cleaning the upstream portion of the sewer. Furthermore, the water need not be disposed of by trucking. After the sewer  42  is cleaned, the cleaned decanted water may be disposed of in the sewer  42 . For example, present systems utilize 60 gallons of water per minute for injection from the cleaning head  14 . If additional water is available for supply to the cleaning head  14 , a better water injection system and cleaning system can be provided. When cleaning a fully charged sewer, i.e., sewer capacity at maximum, the decanted water may be disposed of in a downstream sewer.  
         [0042]     Referring now to  FIG. 2 , the system comprises a truck-mounted high pressure water pump assembly  110  for generating high pressure water, a high pressure water hose  112 , a hose reel  113 , a bullet-shaped cleaning head  114  for receiving high pressure water and cleaning a sewer, a vacuum system comprising a vacuum tube  118  held in place by a boom  119 , an air pump  150  used to create the vacuum, generally located at or near a silencer  151  and a discharge point  152  where air is released to the atmosphere. The system further comprises a waste container  120  for receiving the pumped slurry, a main supply water line  132 , and a main supply water source  134 .  
         [0043]     The high pressure water pump assembly  110  is mounted on, for example, a truck  140 . The purpose of the pump assembly  110  is to pressurize water for use in washing sewer lines  142  by means of cleaning head  114  attached to and in communication with high pressure water hose  112 . The source of water for the pump assembly  110  may be derived from any water source  134 , including a fire hydrant, a tank on the truck  140 , or from the sewer itself.  
         [0044]     The cleaning head  114  is bullet-shaped with a front and rear face. The rear face of the cleaning head  114  has water jet outlets directed backwardly. The truck  140 , high pressure water hose  112  and cleaning head  114  may be of any suitable conventional equipment. When the cleaning head  114  is lowered through a manhole  141 , and into a sewer  142 , high pressure water, such as 2000 psi is applied through the hose  112  to the cleaning head  114 . The high pressure water applied to the cleaning head  114  has several functions. First, the water sprays out of the outlets and the exiting high pressure water washes the solid material from the walls of the sewer  142  and suspends the sewer pipe solid material in a slurry. Additionally, the high pressure water being applied to the cleaning head  114  moves the cleaning head  114  in a direction  143 . After cleaning the sewer  142 , the cleaning head  114  may be retrieved by retracting the high pressure water hose  112  by means of the hose reel  113  as is conventional.  
         [0045]     If conditions dictate that a vacuum system be used, i.e., if a relatively small volume of liquid exists in the sewer  142 , a vacuum system comprising a vacuum tube  118  held in place by a boom  119 , an air pump  150 , generally located at or near a silencer  151  and a discharge point  152  where air is released to the atmosphere, is provided. The air pump  150  creates a negative pressure in the system, causing slurry to be sucked up through the vacuum tube  118  and into the waste container  120 . The solid material in the waste slurry then falls to the bottom of the waste container  120 . The air pump  150  continues to pull the air in the container through the air pump  150 , and through the silencer  151  before being released to the atmosphere through the discharge point  152 .  
         [0046]     The embodiment depicted in  FIG. 2  is less efficient than that depicted in  FIG. 1 , because a submersible pump is capable of moving waste slurry at a faster rate than a vacuum system. Further, use of a submersible pump allows for decanting of water simultaneously while performing the cleaning operation. This is not possible with a vacuum system. However, because a submersible pump cannot be used effectively when little or no water exists in the pipe to be cleaned, the vacuum system is necessary to deal with these types of situations.  
         [0047]     Loosening solid materials, i.e. debris, mud, etc. from the walls of the waste collection system and getting the solid materials to the submersible pump  16  requires a high pressure stream of water. A pressurized water pumping system as described above is not always available or practical for cleaning the waste collection system. Referring now to  FIGS. 4 and 5 , a kite  44  is illustrated schematically. The kite  44  is placed in sewer  42   a  upstream of submersible pump  16   a . Water flowing in sewer  42   a  is blocked by the kite  44  acting effectively as a dam. The only exit for the dammed water is through opening  46 . Water builds up behind kite  44  forming a hydrostatic head pressure that creates a high pressure stream of water emitting from the opening  46  of the kite  44  apex. This high pressure stream of water effectively breaks loose solid material attached to the walls of sewer  42   a  and allows sufficient flow rate to suspend the solid materials in the water for subsequent removal by submersible pump  16   a.    
         [0048]     The position of kite  44  in the sewer  42   a  is controlled by cable  50  attached to the kite  44  by lines  48 . Kite  44  is made of a flexible water proof material such as, for example, canvas. The flexible material is formed into the shape of a funnel and restrained by lines  48  which in turn are attached to the cable  50 .  
         [0049]     Referring now to  FIG. 6 a  Wayne ball  54  is illustrated schematically. The Wayne ball  54  is a ball having a diameter approximately the same size as the inside diameter of the pipe to be cleaned. The Wayne ball  54  has concentric helical grooves  56  on its face in which water flows at high pressure while rotating the Wayne ball  54 . The position of Wayne ball  54  is controlled by cable  60  which is pivotally attached by means of pivot  58 . The rotation of Wayne ball  54  and the high pressure streams of water emitting from grooves  56  agitates the solid materials built up on the walls of sewer  42   b . In addition, the high pressure water effectively washes and cleans the material from the walls while moving the suspended solids down toward the submersible pump  16   b.    
         [0050]     The present invention is not limited to just cleaning sewers, any waste collection system such as but not limited to sewers, sumps, wet wells, collection tanks, digesters, clarifiers, classifiers, etc. where cleaning and removal of solid and liquid materials is required. The present invention is a new, novel and more efficient way of capturing solid and liquid waste by emulsifying the solids in suspension and capturing it by the means disclosed above. The apparatus of the present invention, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned as well as others inherent therein. While a presently preferred embodiment of the invention has been given for the purpose of disclosure, numerous changes in the details of construction and arrangement of parts will readily suggest themselves to those skilled in the art and which are encompassed within the spirit of the invention and the scope of the appended claims.