Method and apparatus for processing and re-using of gray water for flushing toilets

• US 20040045910A1
• Filed: 07/03/2003
• Published: 03/11/2004
• Est. Priority Date: 07/03/2002
• Status: Active Grant

• Current Assignee: Airbus Operations GmbH (Airbus SE)
• Original Assignee: Airbus Deutschland GmbH (Airbus SE)
• Inventors: Hoffjann, Claus, Heinrich, Hans-Juergen
• Granted Patent: US 7,118,677 B2
• Time in Patent Office: Days
• US Class Current: 210/758
• CPC Class Codes: B64D 11/02 Toilet fittings of general application A47K
• CPC Class Codes: C02F 1/001 Processes for the treatment of water whereby the filtration technique is of importance C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00
• CPC Class Codes: C02F 1/4672 by electrooxydation
• CPC Class Codes: C02F 2103/002 Grey water, e.g. from clothes washers, showers or dishwashers
• CPC Class Codes: C02F 2209/42 Liquid level
• CPC Class Codes: C02F 9/20 Portable or detachable small-scale multistage treatment devices, e.g. point of use or laboratory water purification systems
• CPC Class Codes: E03B 1/042 Details thereof, e.g. valves or pumps
• CPC Class Codes: E03B 2001/045 using household water
• CPC Class Codes: E03D 5/003 Grey water flushing systems
• CPC Class Codes: Y02A 20/30 Relating to industrial water supply, e.g. used for cooling
• CPC Class Codes: Y02T 50/40 Weight reduction

Abstract

In order to use so-called gray water for the flushing of toilets, for example in a conveyance such as a passenger aircraft, the gray water is passed through at least one filter, preferably through a coarse filter followed by a fine filter, into a treatment tank where it is anodically oxidized. The rinsing is performed by a pump that may be a rotary pressure pump or a piston cylinder pump. The pump passes the processed or oxidized water through an excess pressure valve and through at least one spray nozzle into a toilet bowl.

Claims

1. A method for processing and reusing gray water for flushing a toilet bowl, comprising the following steps:

a) filtering said gray water to provide filtered water,

b) collecting said filtered water in a processing tank,

c) processing said filtered water by anodically oxidizing said filtered water in said processing tank to provide processed water, and

d) using said processed water for flushing said toilet bowl in a toilet.

2. The method of claim 1, wherein said filtering step comprises a coarse filtering operation and a fine filtering operation for removing dirt, coloring agents, and odor causing agents from said gray water.

3. The method of claim 2, wherein said fine filtering is performed in said processing tank and said coarse filtering is performed outside said processing tank.

4. The method of claim 3, further comprising using an exchangeable, externally accessible fine filter in said processing tank.

5. The method of claim 3, further comprising using an exchangeable, externally accessible coarse filter in a lavatory basin or next to a lavatory basin.

6. The method of claim 1, wherein said step of anodically oxidizing is performed to such an extent that germ growth is prevented in or on any component of a water distribution system through which said processed water is distributed.

7. The method of claim 1, further comprising detecting through a sensor at least one filling level in said processing tank to produce a control signal for controlling a water flow.

8. The method of claim 1, further comprising providing an overflow discharge in said processing tank and feeding said overflow discharge into a gray water collecting conduit.

9. The method of claim 8, further comprising leading said gray water collecting conduit into an outboard draining mast or device.

10. The method of claim 8, further comprising leading said gray water collecting conduit into a collecting container near a wastewater collecting tank.

11. the method of claim 10, further comprising pressurizing said gray water and passing pressurized gray water through spray nozzles for rinsing said wastewater tank and other system components.

12. The method of claim 7, further comprising detecting said at least one filling level as a minimum filling level, producing said control signal as a minimum level control signal for controlling a fresh water supply faucet of a lavatory basin in a toilet for replenishing water in said processing tank to a medium filling level from a fresh water supply.

13. The method of claim 12, further comprising sensing an unoccupied status of said toilet to provide an unoccupied control signal, and automatically opening said fresh water faucet only in response to said minimum level control signal and in response to said unoccupied control signal.

14. The method of claim 12, further comprising using an infrared detector and a toilet door switch for producing an “

occupied”

signal to disable said automatic opening of said fresh water faucet when said toilet is occupied.

15. The method of claim 1, further comprising monitoring and controlling all system functions, status characteristics and operations through a central processing unit and respective sensors.

16. The method of claim 15, further comprising presetting in said central processing unit a defined temperature range for water passing through a faucet in said lavatory or toilet.

17. The method of claim 1, further comprising sensing a plurality of filling levels including a maximum filling level and a minimum filling level in said processing tank to produce respective control signals for controlling the withdrawal of processed water from said processing tank so that more processed water is withdrawn from said processing tank in response to a higher filling level signal and less processed water is withdrawn from said processing tank in response to a lower filling level signal.

18. The method of claim 1, further comprising sensing a plurality of filling levels including a high filling level and a low filling level in said processing tank to produce respective high filling level and low filling level control signals for controlling a fresh water supply faucet of a lavatory basin in such a way that a larger fresh water volume is supplied through said faucet and lavatory basin into said processing tank in response to said low filling level signal and a smaller fresh water volume is supplied through said faucet and lavatory basin into said processing tank in response to said high filling level control signal.

19. An apparatus for processing and reusing gray water, said apparatus comprising:

a) at least one filter having a filter inlet connected to a source of said gray water, and a filter outlet,

b) a processing tank having an inlet connected to said filter outlet,

c) means for anodically oxidizing filtered water in said processing tank to provide processed, oxidized water, and

d) a pump connected with a pump inlet to said processing tank, an excess pressure valve connected to an outlet of said pump, at least one rinsing spray nozzle installed in a toilet bowl and connected to said excess pressure valve for rinsing said toilet bowl in response to a generated control signal for a predetermined time interval at the end of which said pump is automatically switched off and said excess pressure valve is closed again.

20. The apparatus of claim 19, wherein said pump is a rotary pump.

21. The apparatus of claim 19, wherein said pump comprises a cylinder and a piston in said cylinder, said apparatus further comprising a detector positioned for detecting an end position of said piston indicating that processed water in said cylinder has been discharged, said detecting providing a control signal, a motor responsive to said control signal for driving said piston back into a starting position, whereby processed water is sucked into said cylinder for a next toilet bowl rinse.

22. The apparatus of claim 19, further comprising a central control unit, sensors for providing status signals to said central control unit, at least one first power supply for said pump, a faucet for supplying fresh water to a lavatory basin, at least one second power supply for a faucet control, a suction device connected to said toilet bowl, and at least one third power supply for said suction device, and wherein said central control unit controls said first, second and third power supplies in response to said control signals.

23. The apparatus of claim 22, further comprising a communication area network (CANBUS) to which said central control unit is connected for communicating with other systems.

24. The apparatus of claim 19, further comprising separate conduits for freshwater, gray water and waste water, and wherein a direct connection between said conduits is avoided.

25. The apparatus of claim 19, installed in an aircraft.