Patent ID: 12188218

DETAILED DESCRIPTION OF THE INVENTION

As depicted inFIG.1, a sewer cleaning system10according to one embodiment of the invention is mounted to a frame12of a truck14. The combination of a sewer cleaning system mounted on the frame of a truck is sometimes referred to as a jet/vac truck. In general, the sewer cleaning system10illustrated and described herein recycles/reclaims water used during the sewer cleaning process so that less “clean water” (defined as fresh water carried to the jobsite in tanks by the truck or provided from an alternative fresh water source) overall is required while cleaning a sewer line. That is, instead of using only clean water to clean the sewer lines, the recycled/reclaimed water may be used again to assist with cleaning the sewer line. As such, the sewer cleaning system10is more ecologically friendly as it uses less clean water during the sewer cleaning process. Further, because the water is recycled/reclaimed, the jet-vac truck does not have to leave the job site as frequently to take on additional clean water, resulting in fewer job interruptions, if at all, and therefore, takes less time to complete the sewer cleaning process.

With reference toFIGS.1-3, the sewer cleaning system10includes four separate water tanks16attached to the outside of a cylindrical debris tank18whose longitudinal axis is horizontal and generally parallel to the longitudinal axis of the truck14. While this particular sewer cleaning system includes four separate water tanks16, fewer or more water tanks may be used depending on how much water is desired to be transported by the truck14. A moveable vacuum hose20is coupled to the top of the debris tank18. The vacuum hose20is mounted on a boom22that is pivotally coupled to the top of the debris tank18. As such, the vacuum hose20may be rotated 360 degrees around the truck14. To create vacuum in the vacuum hose20, the sewer cleaning system10includes a vacuum-generating system24that is connected to an opening26in the debris tank18via a conduit28. When operating, the vacuum-generating system24draws air from the debris tank18to create a negative pressure in the debris tank18causing a suction effect in the vacuum hose20. The length of the vacuum hose20may be extended by attaching additional individual hose sections30, which may be stored behind a cab32of the truck14.

The sewer cleaning system10further includes a high-pressure pump40operatively coupled to the water tanks16. The high-pressure pump40receives water from the water tanks16, pressurizes the water, and sends the pressurized water to a water hose42mounted on a retractable reel44mounted to the back of the debris tank18. The free end of the water hose42includes a water jet nozzle (not shown) that discharges the pressurized water into the sewer line to clear debris in and attached to the sewer line. The water jet nozzle also uses the discharged water to move the detached debris back towards the well/basin at the conjunction of the vertical access shaft and the sewer line.

The vacuum hose20is then used to withdraw the mixture of water and detached debris from the well/basin. The mixture travels through the vacuum hose20and is discharged from outlet tube46(FIG.4) inside the debris tank18.FIG.4also depicts the opening26in the debris tank18which is connected to the vacuum-generating system24. When operating, the vacuum-generating system24draws air from inside the debris tank18through the opening26thereby generating negative pressure in debris tank18which causes suction in the vacuum hose20. As depicted inFIG.4, a cage inside the debris tank18is coupled to the opening26. Inside the cage50is a suspended spherical float52. Should the water level (depicted as dashed line54) rise in the debris tank18and contact the spherical float52, the water will raise the spherical float52upwards and, at some point, the spherical float52will close the opening26so as to stop further air being removed from the debris tank18. Consequently, with the opening26closed there will be no more suction (vacuum) created in the vacuum hose20and no additional mixture of water and debris will be pulled into the debris tank18. When the water level54decreases, the spherical float52will move downwardly and away from the opening26so that air may be removed from the debris tank18to create suction (vacuum) in the vacuum hose20.

With reference toFIGS.4,5, and5A, the front end of the debris tank18includes a bulkhead60which includes a debris sieve62. In an embodiment, the debris sieve62may have a circular perimeter. The debris sieve62includes a first side64and a second side66with an array of through holes68passing from the first side64to the second side66. The through holes68are sized to allow water to flow through, but not allow particulate matter of a certain diameter to pass. In an embodiment, the through holes68in the debris sieve62may have a diameter in the range of 100 microns to 700 microns. The debris tank18also includes a fluid chamber70defined by the bulkhead60/debris sieve62and a front cap71of the debris tank18. The fluid chamber70receives the water passing through the through holes68from the first side of the debris sieve62to the second side66. In an embodiment, the debris tank18may include a course mesh/grate72that is positioned adjacent to the debris sieve62. The mesh/grate72has openings74that are much larger than the through holes68in the debris sieve62. The mesh/grate72is intended to keep larger debris in the debris tank18from contacting and/or clogging the through holes68in the debris sieve62. In that respect, the mesh/grate72represents the first filtering device in the reclamation of the water from the mixture of water and debris in the debris tank18.

An extraction pump76(FIG.3) is mounted to the front of the debris tank18and is in fluid communication with the fluid chamber70via an extraction pipe78, one end of which is positioned proximate the bottom of the fluid chamber70. When the extraction pump76is activated, it draws the water inside the fluid chamber70through the extraction pipe78.

In one embodiment, the extraction pump76will transfer the extracted water from the fluid chamber70into one or more particulate filters84(FIG.3) that are configured to remove additional remaining debris in the water of a certain diameter. If the through holes68in the debris sieve62have a diameter of 100 microns, it may be possible to eliminate the particulate filters84. Retaining the particular filters84, however, adds another layer of filtering of the water to insure no particulate over 100 microns reaches the water tanks16and the high-pressure pump40. Although five particulate filters84are depicted inFIG.3, fewer or more particulate filters84may be used in the sewer cleaning system10. Once the water leaves the one or more particulate filters84, it returns to the water tanks16. In an embodiment, the one or more particulate filters84remove particulates in the water coming from the fluid chamber70greater than or equal to 100 microns. The water with particulates less than 100 microns may pass through the high-pressure pump40without causing damage to the high-pressure pump40. In this configuration, the water passing from the debris tank18and through debris sieve62and the particulate filters84may be continuously passed through the high-pressure pump40, the water hose42, the vacuum hose20, and back into the debris tank18. Not all water brought to the job site in the water tanks16will be recovered by the vacuum hose20as it sucks the water and debris mixture from the well/basin. Thus, the filtering and reusing of the water cannot continue indefinitely as a certain percentage of water will be lost during the sewer cleaning process. Nonetheless, the amount of water filtered and reused during the sewer cleaning process will be many times the capacity of the water tanks16. Consequently, the sewer cleaning system10will use far less water than prior systems that could clean the sewer lines only until the water tanks ran out of water. In addition, the sewer cleaning process will be completed faster because the operator does not have to stop during the cleaning process to replenish the water tanks from a remote source of water and/or empty the debris tank18as often as in conventional designs. As will be discussed below with respect toFIG.7, the process of reclaiming and recycling the water in this embodiment may be conducted continuously so long as a sufficient amount of water is being sucked up by the vacuum hose20and deposited into the debris tank18. This process may be considered a continuous operation mode.

In another embodiment, the sewer cleaning system10may be operated in a batch mode instead of the continuous operation mode just described above. With reference toFIGS.3,4, and6, the sewer cleaning when the water and debris level in the debris tank18reaches a predetermined level, the extraction pump is activated to draw water out of the fluid chamber70. That water discharged from the extraction pump76will not be sent, however, to the particulate filters84, but will instead be directed to an inlet port90which is located in the front of the debris tank18and above the extraction pump76. The inlet port90includes a pivotable lid92that when opened reveals a support plate94(FIG.6) with a plurality of openings96that is configured to hold one or more flocculant pucks98. The water from the extraction pump76enters the inlet port90via pipe100which is configured to discharge the water onto the flocculant pucks98on the support plate94causing the flocculant pucks98to dissolve and mix with the mixture of water and debris in the debris tank18. The flocculant material mixes with the debris in the water causing the debris to begin coagulating and falling to the bottom of the debris tank18. During this process, additional water is drawn out of the fluid chamber70by the extraction pump76and is directed back into the inlet port90and over the flocculant pucks98. This cycle continues until the flocculant pucks are fully dissolved and the debris is fully coagulated and has largely fallen to the bottom of the debris tank18. With the debris fully coagulated and the water substantially free of large particulates, the extraction pump76may draw the water from the fluid chamber70and direct it to the particulate filters84and then to the water tanks16. Using the flocculant pucks98to separate the water from the large particulates in the debris tank18is considered a batch mode. In this batch mode, the high-pressure pump40is shut down and the sewer cleaning is stopped while the flocculant pucks98are used to coagulate the large particulates so that the water is separated from the large particulates in the debris tank18. In the end, the particulates are coagulated and the water is essentially separated from and cleared of the particulates. The cleared water is then run through the particulate filters84and put back into the water tanks16before the sewer cleaning process resumes. Completing the coagulation process before restarting the sewer cleaning process avoids having a mixture of water and flocculant pass through the particulate filters84and the high-pressure pump40as the flocculant may gum up the particulate filters84and damage the high-pressure pump40. In this embodiment using the flocculant pucks, the outlet tube46preferably extends downwardly approximately one-half the total height of the debris tank18, and preferably extends downwardly approximately two-thirds the total height of the debris tank18, of the debris tank18so that when the vacuum is operating, the incoming mixture of water and debris from the sewer line is positively directed to the bottom of the debris tank18. As such, the air entrained in the incoming mixture reduces the specific gravity of the debris in the bottom of debris tank18, which promotes settling of the flocculated particulates.

The debris tank18may further include a back flush port106which is located at the front of the debris tank18as depicted inFIGS.3-4. The back flush port106opens up to provide access to the fluid chamber70and the second side66of the debris sieve62, which faces the fluid chamber70. After a certain amount of water flows from the debris tank18and through the through holes68in the debris sieve62, the through holes68in the debris sieve62may become partially or fully clogged with debris which will begin to reduce the amount of water that can flow through the debris sieve62. The back flush port106allows for a water hose, for example, to be inserted through the back flush port106and into the fluid chamber70. The water hose can then direct clean, pressurized water into the debris sieve62so as to push debris clogging the through holes68in the debris sieve62back into the debris tank18. This process may be referred to as back flushing the debris sieve62. Other automated systems to back flush the debris sieve62may be employed. For instance, the fluid chamber70may include an array of water jet nozzles (not shown) pointed towards the debris sieve62. The water jet nozzles may be configured to spray water at the debris sieve62automatically based upon a certain amount of time that the extraction pump76has run or based on how many gallons of water have passed through the extraction pump76.

A flowchart inFIG.7depicts one particular workflow of the sewer cleaning system10at a jobsite. The truck14with the sewer cleaning system10would arrive at the jobsite with the water tanks16filled with clean water. The water hose42with the water jet nozzle would be placed into the underground sewer line and the high-pressure pump40would send high pressure water from the water tanks16to the water jet nozzle, which would knock debris from the walls of the sewer line. As the water hose42is drawn back, the high pressure water from the water jet nozzle pushes the fallen debris back towards and into the well/basin. The vacuum-generating system24may then be activated to cause suction (vacuum) in the vacuum hose20so the vacuum hose20may suck up the water and debris in the well/basin and deposit it into the debris tank18via outlet tube46. As the debris tank18fills up, the water in the debris tank18begins to pass through the through holes68in the debris sieve62into the fluid chamber70. The extraction pump76will then withdraw the water from the fluid chamber70via the extraction pipe78which directs the water to the particulate filters84. That filtered water goes back into the water tanks16for re-use in the sewer cleaning process. This process of reclaiming and recycling the water may be conducted continuously so long as a sufficient amount of water is being sucked up by the vacuum hose20and deposited into the debris tank18.

A flowchart inFIG.8depicts the sequence when flocculant pucks98are used as part of the reclamation and recycling process. As described above, when flocculant pucks98are used the water reclamation and recycling process is considered a batch mode. The extraction pump76withdraws the water from the fluid chamber70and flows it over the flocculant pucks98, causing them to dissolve. The flocculant material enters the debris tank18and then begin to coagulate the particles in the water. As the flocculant pucks98are dissolved, more and more of the debris is coagulated. After the coagulation is maximized, the water withdrawn from the fluid chamber70is directed to the particular filters84and then to the water tanks16. With all or a vast majority of the water removed from the debris tank18and placed in the water tanks16, the sewer cleaning process may continue until the water in the water tanks16is depleted.

The sewer cleaning system10is effective in reclaiming, filtering, and recycling water without using any mechanical separation devices, such as centrifuges or vibratory screens, to separate the particulates from the water. As such, the sewer cleaning system10is less complicated and less expensive to manufacture, operate, and maintain compared to other systems using mechanical separation devices.

The sewer cleaning system10described above and depicted in the drawings is mounted to the truck14so that the sewer cleaning system10may be readily transported from one job site to another. The sewer cleaning system10, however, may be mounted to a stationary frame or foundation that is not intended to be moved. In other words, the sewer cleaning system10described herein is not limited for use on a truck.

While the invention has been illustrated by a description of various embodiments, and while these embodiments have been described in considerable detail, it is not the intention of the Applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the Applicant's general inventive concept.