Method and system for cleaning a water basin floor

• US 6,017,400 A
• Filed: 05/15/1998
• Issued: 01/25/2000
• Est. Priority Date: 05/15/1997
• Status: Expired due to Fees

• Current Assignee: Orange County Public School District
• Original Assignee: Orange County Public School District
• Inventors: Holt, John, Miyake, Michio, Flowers, Allan, Clark, Andrew M., Neely, Jerry, Lopata, Marc
• Primary Examiner(s): Till, Terrence R.
• Application Number:
  US09/079,964
• Time in Patent Office: 620 Days
• Field of Search: 15/1.7, 134/21, 210/143, 210/169, 210/406, 210/416.2
• US Class Current: 134/21
• CPC Class Codes: E02F 3/8858 Submerged units self propelled units for burying conduits or cables in trenches under water E02F5/105
• CPC Class Codes: E02F 3/902 for modifying the concentration of the dredged material, e.g. relief valves preventing the clogging of the suction pipe
• CPC Class Codes: E02F 3/907 Measuring or control devices, e.g. control units, detection means or sensors E02F3/902 takes precedence
• CPC Class Codes: E02F 3/925 with jets
• CPC Class Codes: E02F 5/287 with jet nozzles digging devices with blowing effect per se E02F3/9206
• CPC Class Codes: E04H 4/1654 Self-propelled cleaners

Abstract

A method and system for cleaning an underwater floor is disclosed. The method includes: submerging a self-propelled underwater vehicle into a body of water, such as a basin, for example; directing the vehicle to traverse the basin floor; suctioning sediment particles from the basin floor as the vehicle traverses the floor; and providing a suction force to the vehicle. In one embodiment, the act of suctioning includes removing substantial amounts of particles smaller than a predetermined size from the floor while not removing substantial amounts of particles larger than the predetermined size from the floor. The system includes: the submersible, self-propelled vehicle for traversing the underwater floor; a first vacuum hood, coupled to the vehicle, for suctioning sediment particles from the underwater floor; and a first pump, coupled to the hood, for providing a suction force to the hood. In one embodiment, the first vacuum hood is configured to remove substantial amounts of particles smaller than a predetermined size from the floor while not removing substantial amounts of particles larger than the predetermined size from the floor.

Claims

1. A system for cleaning sediment from the sandy, underwater floor of a water seepage basin, comprising:

a submersible, self-propelled apparatus for traversing the underwater floor;

a vacuum hood, coupled to the apparatus, having a flow cross sectional area to suction sediment from the underwater floor; and

a pump, coupled to the hood, for providing a water flow rate to the hood;

said cross sectional area of said vacuum hood and said water flow rate of said pump coordinating to separate sediment from sand particles suctioned from the underwater floor.

2. The system of claim 1 further comprising a rotary agitator, coupled to said vacuum hood and laterally located along a bottom, front portion of said vacuum hood, said rotary agitator agitating and loosening sediment particles resting on the underwater floor.

3. The system of claim 1 further comprising a second vacuum hood coupled to an opposite end of said submersible vehicle in relation to said vacuum hood.

4. The system of claim 1 further comprising an agitator for loosening said sediment particles resting on the underwater floor.

5. A system for cleaning sediment from the sandy, underwater floor of a water seepage basin, comprising:

a submersible, self-propelled apparatus for traversing the underwater floor;

a vacuum hood, coupled to the apparatus, for selectively suctioning sediment in preference to sand particles from the underwater floor;

a pump, coupled to the hood, for providing a suction force to the hood;

a navigational system, coupled to the submersible apparatus, for indicating the location of the apparatus; and

a remote control console, coupled to the navigational system and the submersible apparatus, for receiving apparatus position data from the navigational unit and controlling the movement of the apparatus.

6. The system of claim 5 wherein said navigational system is a global positioning system.

7. The system of claim 5 further comprising at least one buoyancy control tank, coupled to the submersible apparatus, for controlling the buoyancy of the apparatus, wherein air and water inflow and outflow for the tank is controlled by said remote control console.

8. The system of claim 5 wherein said submersible apparatus includes two archimedean screw rotors for providing forward, reverse and lateral motion to the apparatus and wherein said remote control unit controls the rotation speed and the direction of rotation of each of said rotors.

9. A system for cleaning sediment from the sandy, underwater floor of a water seepage basin, comprising:

a submersible, self-propelled apparatus for traversing the underwater floor;

a vacuum hood, coupled to the apparatus, for selectively suctioning sediment in preference to sand particles from the underwater floor;

a pump, coupled to the hood, for providing a suction force to the hood;

a second pump, coupled to the submersible apparatus; and

a plurality of rake tines, coupled to said second pump and laterally dispersed across said vacuum hood, wherein said plurality of rake tines extend to penetrate a specified distance into a bottom layer of the underwater floor, and wherein said plurality of rake tines eject pressurized water received from the second pump to fluidize fine sediment particles from the underwater floor.

10. The system of claim 9 wherein said plurality of rake tines each eject pressurized water in both a forward and upward direction, wherein the pressurized water moving in the forward direction initially loosens and fluidizes said fine sediment particles and the pressurized water moving in the upward direction propels the fine sediment particles upwardly toward a chamber within the said vacuum hood.

11. The system of claim 10 further comprising:

a flow-adjust valve for adjusting the output flow rate of said pump to adjust an output flow rate of said vacuum hood; and

a second flow-adjust valve for adjusting the output flow rate of said second pump, thereby adjusting a flow rate of said plurality of rake tines.

12. The system of claim 11 further comprising:

a pressure sensor, coupled to said flow-adjust valve, for providing an indication of said output flow rate of said pump; and

a second pressure sensor, coupled to an output of said second flow-adjust valve, for providing an indication of said output flow rate of said second pump.

13. The system of claim 9 further comprising:

a first side flap, extending downwardly from a first side peripheral, bottom edge of said vacuum hood to substantially seal a first side gap between the first side peripheral, bottom edge of said vacuum hood and the underwater floor;

a second side flap, extending downwardly from a second side, opposite the first side, peripheral, bottom edge of said vacuum hood so as to substantially seal a second side gap between the second side peripheral, bottom edge of said vacuum hood and the underwater floor; and

a rear flap, extending downwardly from a rear peripheral, bottom edge of said vacuum hood so as to substantially seal a rear gap between the rear peripheral, bottom edge of said vacuum hood and the underwater floor, wherein the first and second side flaps and the rear flap prevent water from flowing into the bottom of said vacuum hood from either the sides or the rear of the first hood.

14. The system of claim 13 further comprising:

a plurality of inlet apertures located on a rear wall of said vacuum hood for providing a compensating inflow of water into said chamber of the first hood; and

wherein a flow rate provided by said pump is greater than the flow rate provided by said second pump and the compensating inflow of water provided by the plurality of inlet apertures compensates for the difference in flow rates provided by said pump and said second pumps.

15. A system for cleaning sediment from the sandy, underwater floor of a water seepage basin, comprising:

a submersible, self-propelled apparatus for traversing the underwater floor;

a vacuum hood, coupled to the apparatus, for selectively suctioning sediment in preference to sand particles from the underwater floor;

wherein said vacuum hood encloses a chamber, the chamber comprising;

a receiving section for initially receiving suctioned particles from the underwater floor;

a return section, located immediately behind the receiving section, for allowing particles to fall to the underwater floor, wherein a separation wall, laterally disposed across an internal, bottom portion of said vacuum hood separates said receiving section and said return section;

a settling section, located immediately above the receiving section and the return section, wherein heavier particles fall from the settling section to the return section and settle back onto the underwater floor;

an outlet valve coupled to said first pump; and

an exit section, located immediately above the settling section, wherein any suspended particles reaching the exit section are propelled through the exit section to an outlet valve; and

a pump, coupled to the hood, for providing a suction force to the hood.

16. A system for clearing sediment from the sandy, underwater floor of a water seepage basin, comprising:

a submersible, self-propelled apparatus for traversing the underwater floor;

a vacuum hood, coupled to the apparatus, for selectively suctioning sediment in preference to sand particles from the underwater floor;

a pump, coupled to the hood, for providing a suction force to the hood; and

a wear plate, coupled to a leading, bottom portion of said vacuum hood, for smoothing a path to be traversed by said vacuum hood.

17. A system for cleaning sediment from the sandy, underwater floor of a water seepage basin, comprising:

a submersible, self-propelled apparatus for traversing the underwater floor;

a vacuum hood, coupled to the apparatus, for selectively suctioning sediment in preference to sand particles from the underwater floor;

a pump, coupled to the hood, for providing a suction force to the hood;

a second vacuum hood coupled to an opposite end of said submersible vehicle in relation to said vacuum hood; and

a valve for selectively coupling said first pump selectively to said first and second vacuum hoods.

18. A system of claim 17 further comprising:

a second pump, coupled to the submersible vehicle;

a first plurality of rake tines, selectively coupled to said second pump and to said vacuum hood so as to be laterally dispersed across a bottom, leading portion of the first hood; and

a second plurality of rake tines, selectively coupled to said second pump and to said second vacuum hood and laterally dispersed across a bottom, leading portion of said second hood.

19. The system of claim 18 further comprising a second three-way valve, coupling said second pump to said first and second plurality of rake tines.

20. An underwater cleaning vehicle, comprising:

a chassis having a front portion, a rear portion and two side portions;

an archimedean screw rotor rotatably coupled to the chassis for providing mobility to the vehicle; and

a first vacuum hood, coupled to the chassis.

21. The underwater cleaning vehicle of claim 20 further comprising:

a first pump, coupled to said vacuum hood, for providing a suction force to said vacuum hood;

a first plurality of rake tines, coupled to said vacuum hood and laterally dispersed across a bottom, leading portion of said vacuum hood; and

a second pump, coupled to said plurality of rake tines, for providing pressurized water to the said plurality of rake tines.

22. A system for cleaning an underwater floor, comprising:

a submersible, self-propelled vehicle for traversing the underwater floor;

an enclosure, coupled to said submersible vehicle, for containing sediment particles from the underwater floor;

a pump attached to said enclosure for selectively removing sediment in preference to sand from said enclosure;

a navigation system for indicating the location of the vehicle; and

a steering system for controlling the movement of the vehicle.

23. A system for cleaning an underwater floor, comprising:

a submersible, self-propelled vehicle for traversing the underwater floor;

an enclosure, coupled to said submersible vehicle, for containing sediment particles from the underwater floor;

a pump attached to said enclosure for selectively removing sediment in preference to sand from said enclosure; and

a plane positioned to smooth a path to be traversed by said submersible vehicle.

24. A system for cleaning an underwater floor, comprising:

a submersible, self-propelled vehicle for traversing the underwater floor;

an enclosure, coupled to said submersible vehicle, for containing sediment particles from the underwater floor;

a pump attached to said enclosure for selectively removing sediment in preference to sand from said enclosure;

a second enclosure coupled to an opposite end of said submersible vehicle in relation to said first enclosure;

a first agitator coupled to said enclosure for fluidizing said sediment particles resting on the underwater floor; and

a second agitator coupled to said second enclosure for fluidizing said sediment particles resting on the underwater floor.

25. An underwater cleaning vehicle, comprising:

a drive system for providing mobility to the vehicle on an underwater floor;

a first vacuum for suctioning sediment particles from the basin floor;

a second vacuum for suctioning sediment particles from the basin floor; and

a vacuum control to selectively operate said first and second vacuum in accordance with the direction of travel of said vehicle.

26. The underwater cleaning vehicle of claim 25 further comprising:

a first pump coupled to said first and second vacuums to draw fluid therefrom;

a first agitator coupled to said first vacuum for ejecting pressurized water onto the underwater floor and fluidizing said sediment particles on the underwater floor;

a second agitator coupled to said second vacuum for ejecting pressurized water onto the underwater floor and fluidizing said sediment particles on the underwater floor; and

a second pump coupled to the first and second agitators for providing said pressurized water to said first and second agitators.

27. The underwater cleaning vehicle of claim 25 further comprising a buoyancy control chamber on said vehicle.

28. A method of cleaning an underwater floor, comprising:

submerging a vehicle such that it comes to rest on the underwater floor;

directing the vehicle to traverse the underwater floor;

selectively suctioning sediment particles from the underwater floor while leaving sand and gravel in place as the vehicle traverses the floor; and

providing a suction force to the vehicle.

29. The method of claim 28 wherein said act of selectively suctioning comprises removing substantial amounts of particles smaller than a predetermined size from the floor while not removing substantial amounts of particles larger than said predetermined size from the floor.

30. The method of claim 29 wherein said act of removing substantial amounts of particles smaller than a predetermined size from the floor while not removing substantial amounts of particles larger than the predetermined size from the floor, comprises:

directing particles, via a vacuum suction force, into a first chamber of a vacuum hood, coupled to said vehicle;

subsequently directing said particles into a second chamber of said vacuum hood, wherein gravity forces said particles larger than the predetermined size to fall back to the underwater floor via a return channel located immediately below the second chamber, at a bottom, rear portion of said vacuum hood; and

subsequently directing any remaining particles which have not fallen back to the underwater floor to a third chamber having a volume smaller than the second chamber such that there is an increased flow velocity in said third chamber compared to the second chamber.

31. The method of claim 28 wherein said act of directing said vehicle comprises:

receiving positional data from an on-board navigational system located on the vehicle;

displaying information derived from the positional data on a display screen of a remote navigational system located on a shore to an operator viewing the display screen; and

controlling the movement of the vehicle underwater, via a remote control console manipulated by the operator.

32. The method of claim 28 further comprising fluidizing fine sediment particles which constitute a top layer of said underwater floor.

33. The method of claim 32 wherein said act of fluidizing comprises ejecting pressurized water below said top layer.

34. The method of claim 28 further comprising agitating and loosening sediment particles resting on the underwater floor.

35. The method claim 28 further comprising:

activating a first vacuum hood, coupled to a front portion of said vehicle, for suctioning sediment particles from the underwater floor when the vehicle is moving in a forward direction; and

activating a second vacuum hood, coupled to a rear portion of the vehicle, for suctioning sediment particles from the underwater floor when the vehicle is moving in a reverse direction.

36. The method of claim 28 further comprising controlling the buoyancy of said vehicle.

37. Apparatus for removing sediment from the submerged granular walls of a percolation source of an underground aquifier, comprising:

an agitator designed to disrupt a surface layer of said submerged granular walls;

wherein said agitator comprises at least one water jet member which ejects pressurized water onto said surface layer of said submerged granular walls, thereby disrupting said sediment and material within the surface layer,

a separator which cooperates with said agitator to divide said sediment from the material of said granular walls; and

a collector which cooperates with said separator to remove divided sediment.

38. Apparatus for removing sediment from the submerged granular walls of a percolation source of an underground aquifier, comprising:

an agitator designed to disrupt a surface layer of said submerged granular walls,

a separator which cooperates with said agitator to divide said sediment from the material of said granular walls, wherein said separator comprises a vacuum hood having a chamber therein, wherein said sediment and material of said granular walls enters into said vacuum hood and are separated by an upward flow which propels smaller sediment particles upwardly toward an outlet valve of the hood and by gravity which forces larger material particles to fall toward said submerged granular walls; and

a collector which cooperates with said separator to remove divided sediment.

39. The apparatus of claim 38 wherein said chamber comprises:

an entrance section for receiving said sediment and material from said surface layer;

a settling section, located above the entrance section, for receiving the sediment and material from the entrance section, wherein the settling section has a volume greater than a volume of the entrance section, such that a flow velocity within the settling section is less than a flow velocity within the entrance section, and wherein particles larger than said predetermined size are separated by gravity from particles smaller than the predetermined size in the settling section;

a return section, located below the settling section, wherein said particles larger than said predetermined size fall through the return section toward said submerged granular walls; and

an exit section, located above the settling section, for receiving any remaining particles from the settling section and guiding the remaining particles to said first pump.

40. Apparatus for removing sediment from the submerged granular walls of a percolation source of an underground aquifier, comprising:

an agitator designed to disrupt a surface layer of said submerged granular walls;

a separator which cooperates with said agitator to divide said sediment from the material of said granular walls; and

a collector which cooperates with said separator to remove divided sediment, wherein said collector comprises a first pump coupled to a vacuum hood having a chamber in which said sediment is divided from said material of said granular walls, wherein the first pump suctions the divided sediment from the chamber.

41. The apparatus of claim 40 further comprising a second pump, coupled to said vacuum hood, for pumping water into said chamber, wherein a first flow rate provided by said first pump is greater than a second flow rate provided by the second pump, and wherein said vacuum hood further comprises at least one inlet aperture for providing a compensating inflow rate.

42. A method of removing clogging material from the walls of an underwater basin without removing other material, the method comprising:

agitating said clogging material and other material from said walls so as to suspend them in water; and

selecting said clogging material from said other material from said walls based on grain size to permit selective removal of said clogging material.

43. The method of claim 42 wherein said act of agitating comprises ejecting pressurized water onto a surface of said walls, thereby disrupting said clogging material and other material from the wall.

44. The method of claim 42 wherein said act of selecting said clogging material from said other material comprises separating larger particles from smaller particles in a vacuum hood.

45. The method of claim 44 wherein said act of separating larger particles from smaller particles comprises:

suctioning said clogging material and said other material from a basin wall into an entrance chamber of said vacuum hood;

directing said clogging material and said other material from the entrance chamber to a settling chamber within the vacuum hood, wherein a volume of the settling chamber is greater than a volume of the entrance chamber such that a flow velocity within the settling chamber is less than a flow velocity within the entrance chamber, and wherein particles larger than a predetermined size are separated by gravity from particles smaller than the predetermined size in the settling chamber;

providing a return channel, located below the settling chamber, wherein said particles larger than said predetermined size fall through the return channel toward said basin wall; and

suctioning any remaining particles through an exit channel, located above the settling chamber.