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

• US 7,118,677 B2
• Filed: 07/03/2003
• Issued: 10/10/2006
• Est. Priority Date: 07/03/2002
• Status: Expired due to Fees

• Current Assignee: Airbus Operations GmbH (Airbus SE)
• Original Assignee: Airbus Deutschland GmbH (Airbus SE)
• Inventors: Hoffjann, Claus, Heinrich, Hans-Juergen
• Primary Examiner(s): Savage, Matthew O.
• Application Number:
  US10/613,530
• Publication Number:
  US 20040045910A1
• Time in Patent Office: 1,195 Days
• Field of Search: 210/748, 210/758, 210/806, 210/203, 210/205, 210/257.1, 210/7.258, 210/259, 210/262, 210/143, 210/149, 210/153, 210/170, 210/172, 210/181, 210/182, 210/192, 210/742, 210/744, 422/2, 422/21, 422/71, 466/5, 205/751, 742/744, 143/149, 143/153, 143/170, 143/172, 143/181, 143/182, 143/192
• US Class Current: 210/744
• 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 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,

wherein said filtering comprises a coarse filtering and a fine filtering for removing dirt, coloring agents, and odor-causing agents from said gray water, and wherein said fine filtering is performed in said processing tank and said coarse filtering is performed outside said processing tank.

2. The method of claim 1, further comprising using an exchangeable, externally accessible fine filter in said processing tank for performing said fine filtering.

3. The method of claim 1, further comprising using an exchangeable, externally accessible coarse filter connected to a lavatory basin for performing said coarse filtering.

4. 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.

5. 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.

6. The method of claim 5, 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 lavatory for replenishing water in said processing tank to a medium filling level from said fresh water supply faucet.

7. The method of claim 6, further comprising sensing an unoccupied status of said lavatory to provide an unoccupied control signal, and automatically opening said fresh water supply faucet only in response to said minimum level control signal and said unoccupied control signal.

8. The method of claim 6, further comprising using an infrared detector and a lavatory door switch for performing said sensing, and further producing an occupied control signal to disable said automatic opening of said fresh water supply faucet when said lavatory is occupied.

9. 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.

10. The method of claim 9, further comprising leading said gray water collecting conduit into a gray water collecting container.

11. The method of claim 10, further comprising locating said gray water collecting container near a wastewater collecting tank.

12. The method of claim 1, further comprising monitoring and controlling all of said steps through a central processing unit and respective sensors.

13. The method of claim 1, further comprising presetting in a central processing unit a defined temperature range for water passing through a faucet of a lavatory basin having an outlet connected to said processing tank, and using said central processing unit to control a water heater connected upstream of said faucet so as to heat said water as needed to maintain a temperature of said water in said defined temperature range.

14. 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 higher and lower filling level 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 said higher filling level control signal and less processed water is withdrawn from said processing tank in response to said lower filling level control signal.

15. 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 through a faucet and a lavatory basin so that a larger fresh water volume is supplied into said processing tank through said faucet and lavatory basin in response to said low filling level signal and a smaller fresh water volume is supplied into said processing tank through said faucet and lavatory basin in response to said high filling level control signal.

16. The method of claim 15, further comprising starting replenishing water in said processing tank in response to said low filling level control signal and stopping said replenishing in response to said high filling level control signal when water in said processing tank reaches said high filling level.

17. An apparatus for processing and reusing gray water for flushing a toilet bowl, comprising:

a) filter means for filtering said gray water to provide filtered water,

b) a processing tank for collecting said filtered water in said processing tank,

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

d) means for using said processed water for flushing said toilet bowl,

wherein said filter means comprise a coarse filter and a fine filter for removing dirt, coloring agents, and odor-causing agents from said gray water, and wherein said fine filter is arranged in said processing tank and said coarse filter is arranged outside said processing tank.

18. The apparatus of claim 17,

wherein said coarse filter has a coarse filter inlet connected to a source of said gray water and a coarse filter outlet connected to a tank inlet of said processing tank;

and

wherein said means for using said processed water comprises a pump having a pump inlet connected to said processing tank, an excess pressure valve connected to a pump outlet of said pump, a rinsing spray nozzle installed in said toilet bowl and connected to said excess pressure valve for rinsing said toilet bowl with said processed water in response to a generated control signal for a predetermined time interval at the end of which said pump is switched off and said excess pressure valve is closed.

19. The apparatus of claim 18, 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, and 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.

20. The apparatus of claim 18, further comprising a central control unit, sensors for providing status signals to said central control unit, a faucet for supplying fresh water to a lavatory basin, and a suction device connected to said toilet bowl, and wherein said central control unit is connected and adapted to control said pump, said faucet and said suction device in response to said status signals.

21. The apparatus of claim 20, further comprising a communication area network (CANBUS) to which said central control unit is connected for communicating via said communication area network.

22. The apparatus of claim 18, further comprising separate conduits for freshwater, gray water and waste water, and wherein a direct connection between said conduits is avoided.

23. The apparatus of claim 18, installed in an aircraft.