WO2014202975A2

WO2014202975A2 - Water recycling device

Info

Publication number: WO2014202975A2
Application number: PCT/GB2014/051869
Authority: WO
Inventors: Peter William HOLDSWORTH
Original assignee: HOGG, Carolyn Anne Mckenzie
Priority date: 2013-06-18
Filing date: 2014-06-18
Publication date: 2014-12-24
Also published as: GB201310845D0; WO2014202975A3

Abstract

A water recycling device (1) for use in a communal bathroom comprises a first reservoir (5) for receiving and holding greywater to allow suspended solids in the greywater to settle at the bottom of the first reservoir; a greywater inlet pipe (11) through which greywater enters the first reservoir at or towards the bottom of the first reservoir; a waste outlet (21) in the first reservoir through which settled solids can be purged from the first reservoir; a second reservoir (35) for receiving greywater from the first reservoir from which at least some suspended solids have been removed, and in which the greywater may be mixed with potable water; and a water outlet (27) in the second reservoir through which water can be discharged from the second reservoir. Also disclosed is a method for recycling water for use in a communal bathroom.

Description

WATER RECYCLING DEVICE

[001] The present invention relates to a water recycling device, and in particular to a water recycling device suitable for recycling greywater from hand basins for use in flushing toilets and urinals in a communal bathroom.

[002] Water usage is increasing both domestically and industrially, causing water shortages and leading to an overall increasing cost of water.

[003] In view of this increasing cost, ways of reducing fresh water consumption, in both homes and offices, are being sought, either by lowering consumption or by recycling used water.

[004] Used water from domestic sources is conventionally referred to as "greywater" or "black water". Greywater is a term used to define the waste water from domestic sources such as baths, showers, hand basins, washing machines and the like. Black water refers to water which contains human waste

(sewage) . Greywater thus derives its name from its status between fresh, potable water (white water) and water containing human waste (black water) .

[005] In a typical sewerage system, greywater is combined with black water and disposed of in a shared system. However, in recent years, there has been interest in attempting to recycle or reuse greywater rather than simply treating it as waste.

[006] For example, US 6,276,005 describes a water recycling device for use in a domestic setting that uses greywater from a bathroom sink to flush a toilet. The device provides a reservoir below the sink which collects the greywater to be reused. The greywater falls into a trap section of the reservoir where it either flows into the main section of the reservoir after passing through a barrier filter, or overflows into the mains sewer if the reservoir is full. A small pump then transfers the filtered greywater from the main reservoir to a toilet water tank.

[007] The present invention seeks to provide an improved water recycling device, for use in a communal bathroom, for example in an office or public convenience, containing a number of sinks and toilets and/or urinals, for example from 4 to 8 sinks and toilets and/or urinals respectively.

[008] Thus, according to the present invention there is provided a water recycling device for use in a communal bathroom, comprising:

a first reservoir for receiving and holding greywater to allow suspended solids in the greywater to settle at the bottom of the first reservoir;

a greywater inlet pipe through which greywater enters the first reservoir at or towards the bottom of the first reservoir ;

a waste outlet in the first reservoir through which settled solids can be purged from the first reservoir;

a second reservoir for receiving greywater from the first reservoir from which at least some suspended solids have been removed, and in which second reservoir the greywater may be mixed with potable water; and

a water outlet in the second reservoir through which water can be discharged from the second reservoir.

[009] In this way, in use greywater can enter the first reservoir through the greywater inlet pipe such that greywater exits the inlet pipe at or towards the bottom of the first reservoir in such a way that the greywater, together with any soap and other suspended solids contained within, is gently fed into the first reservoir. This allows the greywater to settle, and suspended solids to deposit at the bottom of the first reservoir. The first reservoir has a waste outlet for purging sediment, for example soap residues. As the first reservoir fills with greywater, the settled greywater from the first reservoir flows into the second reservoir where it can be mixed with potable water. The settled and mixed water can then leave the second reservoir through the water outlet, suitable for use, for example, for flushing toilets and/or urinals.

[0010] The device of the present invention has the advantage over many prior art devices in that it can be filter-free. Filters can become blocked, and thus require careful maintenance .

[0011] The water recycling device of the present invention thus comprises a first reservoir for receiving and holding greywater to allow suspended solids in the greywater to settle at the bottom of the first reservoir. The first reservoir may be any suitable water reservoir, such as a conventional water tank. The first reservoir may be made from any suitable material, for example plastics or metal, and of any suitable shape. For example, the first reservoir may be cylindrical, or rectangular, or cubic. The first reservoir preferably has a capacity of from 50 to 75 litres, and can vary in size to accommodate water from any desired number of hand basins. The larger the capacity of the first reservoir, the longer the settlement time for suspended solids in the greywater, which can be beneficial in removing the solids. The first reservoir may be either open or openable, or closed . [0012] In use, greywater enters the first reservoir through the greywater inlet pipe at or towards the bottom of the first reservoir, in such a way that the greywater, together with any soap and other suspended solids contained within is gently fed into the first reservoir. This allows the greywater to settle and suspended solids to deposit at the bottom of the first reservoir. The greywater inlet pipe preferably enters the first reservoir in an upwardly direction, so that the greywater exits the greywater inlet pipe against gravity, so as to slow the flow of the greywater into the first reservoir, promote settling of suspended solids, and reduce or avoid disturbance of settled solids at the bottom of the first reservoir. The greywater inlet pipe may thus be inclined vertically from the horizontal as it enters the first reservoir, and is preferably substantially upright as it enters the first reservoir. This preferred arrangement promotes a so-called "volcano effect" of greywater entering the first reservoir. The greywater inlet pipe enters the first reservoir at or towards the bottom of the first reservoir. For example, in a preferred embodiment the greywater inlet pipe enters the first reservoir through a side wall of the reservoir, and comprises an upward bend towards its exit such that greywater enters the first reservoir in an upright direction. In another preferred embodiment, the greywater inlet pipe enters the first reservoir through the floor of the reservoir in a substantially upright direction.

[0013] The greywater inlet pipe preferably further comprises a dosing pipe for dosing the greywater passing through the greywater inlet pipe with a chemical agent, such as a cleansing or purifying agent, for example an antibacterial agent, for example bleach. In this way, the greywater may be pre-treated to kill bacteria and remove other impurities. The dosing is preferably triggered by a proximity sensor, for example in the greywater inlet pipe, such that as greywater passes through the greywater inlet pipe the sensor triggers a dose of agent to be released, for example from an agent reservoir connected to the dosing pipe, into the greywater. The dose of agent to be released will depend upon the agent in question and the desired result. For example, for bleach, a dose will typically be from 1 to lOppm, for example 5ppm, of greywater.

[0014] The device of the present invention also comprises a waste outlet in the first reservoir, through which settled solids can be purged from the first reservoir. The waste outlet is preferably a suitably positioned pipe, for example at or in the bottom of the first reservoir. The waste outlet may be manually or automatically controlled. For example, the waste outlet may comprise a valve which can be opened, and subsequently closed, manually by a user on demand to purge settled solids from the first reservoir. Alternatively, the waste outlet may comprise a valve, such as a solenoid valve, which is automatically controlled to open and close at regular intervals for a predetermined period of time. For example, the waste outlet may open once every day or period of days, preferably once every 48 hours. The waste outlet may be automatically opened for any desired period, typically from 30 seconds to a minute, preferably for 45 seconds at a time. In this way, sediment build-up is prevented and the water recycling device may operate continuously.

[0015] The device of the present invention preferably further comprises an overflow pipe in the first reservoir through which excess greywater can escape from the reservoir, to prevent the first reservoir from overflowing and/or filling up. The overflow pipe is conveniently positioned at the top of the first reservoir. The overflow pipe preferably further comprises a non-return valve. In this way, the water recycling device may be used when there is a high flow rate through the device.

[0016] The first reservoir preferably further comprises transfer means for transferring settled greywater from the first reservoir to the second reservoir. The transfer means is preferably a pipe, for example a pipe having a diameter of 1 to 2 inches (2.54 to 5.08 cm), for example 1.5 inches

(3.81 cm) . Alternatively, the transfer means may be a channel or a gutter.

[0017] In preferred embodiments, the transfer means is positioned towards the top of the first reservoir, so that the first reservoir has to substantially fill with greywater prior to greywater transferring from the first to the second reservoir. In this way, greywater is held in the first reservoir for longer prior to transfer, which promotes greater settling of solids. For example, the transfer means may be positioned such that the greywater volume in the first reservoir must reach a volume of between 50 and 75 litres before transfer. In a preferred embodiment, the volume of greywater in the first reservoir must reach from 60 to 70 litres, more preferably substantially 65 litres, before beginning to flow from the first reservoir to the second reservoir .

[0018] The device of the present invention preferably further comprises a debris deflector plate adjacent the transfer means, for preventing floating solids from passing through the transfer means into the second reservoir. The debris deflector plate may comprise a plate of a suitable material, for example a metal, which is preferably positioned substantially parallel and away from the wall of the first reservoir in which the transfer means is positioned. For example, the debris deflector plate may be positioned from 50 to 100mm from the wall containing the transfer means, for example approximately 75mm. The debris deflector plate may extend across the entire breadth of the first reservoir. If present, the debris deflector plate preferably extends to above the overflow pipe, and preferably extends to below the transfer means. Thus, the debris deflector plate may be from 100 to 200mm deep, for example 150mm deep.

[0019] The device of the present invention further comprises a second reservoir for receiving greywater from the first reservoir from which at least some suspended solids have been removed. As for the first reservoir, the second reservoir may be any suitable water reservoir, such as a conventional water tank. The second reservoir may be made from any suitable material, for example plastics or metal, and of any suitable shape. For example, the second reservoir may be cylindrical, or rectangular, or cubic. The second reservoir preferably has a capacity of from 50 to 75 litres, and can vary in size to provide water to any desired number of toilets or urinals. The second reservoir may be either open or openable, or closed.

[0020] In use, greywater is mixed with potable (white) water in the second reservoir. The second reservoir thus preferably further comprises potable water inlet apparatus, by which potable water may be added to the second reservoir for mixing with the settled greywater. The potable water inlet apparatus may comprise conventional pumping apparatus for pumping potable water into the second reservoir. The pumping apparatus may be automatically or manually controlled. Alternatively, the potable water may enter the second reservoir under mains water pressure. The pumping apparatus may comprise a valve, such as a solenoid valve, for allowing potable water to enter the second reservoir. The potable water preferably enters the second reservoir at or towards the top of the reservoir, so that it may fall into the reservoir thus promoting mixing with greywater.

[0021] The device of the present invention comprises a water outlet in the second reservoir through which water can leave the second reservoir. The water outlet may be a pipe, for example a pipe having a diameter of from 1 to 2cm, e.g. 1.5cm. The water outlet may preferably further comprise a distribution pump for pumping the mixed potable and greywater out of the second reservoir, for example to the cistern of a toilet and/or urinal. In this way, a toilet or urinal may be supplied with mixed potable and greywater for flushing, instead of potable water alone. This can result in a saving on mains water consumption in the toilet or urinal, for example of up to 25%.

[0022] The water recycling device preferably further comprises water level control means for controlling the water level in the second reservoir. The control means preferably comprises low level and/or high level proximity detectors, for detecting when the water level in the second reservoir reaches a predetermined lower and/or upper level respectively. The control means preferably uses the high and/or low level proximity detectors in combination with the potable water inlet apparatus and water outlet so that the level of water in the second reservoir may be controlled. Thus, in preferred embodiments when the lower proximity detector detects the water level as being at a predetermined minimum level, potable water enters the second reservoir and water is prevented from leaving the second reservoir through the water outlet, for example in preferred embodiments by cutting power to the water outlet pump, so that the water level in the second reservoir rises, and continues to rise until the upper proximity detector detects the water level as being at a predetermined upper level, at which point potable water stops entering the second reservoir, and water may once again be permitted to leave the reservoir through the water outlet. For example, in preferred embodiments the proximity detectors are used to maintain the volume of water in the second reservoir from between 20 and 30 litres, for example at or around 24 litres.

[0023] The discharge of mixed potable and greywater out of the second reservoir is preferably controlled by the discharge of water from the cistern of a toilet and/or urinal supplied with water by the device of the present invention, in combination with the water outlet. For example, the ball valve in the cistern may close when the cistern is full, causing the water pressure in the water outlet to build. When a predetermined pressure is reached, for example 1.5 bar, the water outlet shuts off. When a toilet or urinal is flushed and the ball valve opens, the pressure drops and the water outlet switches back on. There is also preferably an overpressure switch set at 3 bar, in series. [0024] The water recycling device preferably runs on 24 volts .

[0025] According to the present invention there is also provided a method for recycling water for use in a communal bathroom, the method comprising the steps of:

receiving and holding greywater in a first reservoir to allow suspended solids in the greywater to settle at the bottom of the first reservoir, the greywater entering the first reservoir at or towards the bottom of the first reservoir through a greywater inlet pipe;

purging settled solids from the first reservoir through a waste outlet;

receiving greywater from which at least some suspended solids have been removed in a second reservoir from the first reservoir; mixing the greywater with potable water in the second reservoir; and

discharging the water from the second reservoir through a water outlet in the second reservoir.

[0026] The method of the present invention is preferably performed using the device of the present invention, as described herein. [0027] The present invention will now be described in detail with reference to the accompanying drawing, in which:

Figure 1 shows a representative diagram of a water recycling device of the present invention.

[0028] Thus, Figure 1 shows a water recycling device 1 of an embodiment of the present invention. The device 1 is for use in recycling greywater in a communal bathroom, for example a bathroom comprising from 4 to 8 sinks and toilets and/or urinals respectively, and comprises a first reservoir 5 having a greywater inlet pipe 11, which enters the first reservoir 5 through its side wall and has an opening 19 pointing upwardly, a transfer pipe 3 towards the top of the first reservoir 5 for transferring greywater from the first reservoir 5 to a second reservoir 35, an overflow pipe 16 with a non-return valve 15 towards the top of the first reservoir 5 as well as a waste outlet pipe 21 with a solenoid valve 17 at the bottom of the first reservoir 5. A dosing pipe 9 with a dosing reservoir 7 and a proximity detector 13 are provided connected to the inlet pipe 11 for dosing the inlet pipe 11 with bleach at a level of 5ppm of greywater. The device 1 further comprises a debris deflector plate 22 adjacent the transfer pipe 3, for preventing floating solids from passing through the transfer pipe 3 into the second reservoir 35. The debris deflector plate 22 comprises a plate of a suitable material, for example a metal, and is positioned substantially parallel and approximately 75mm away from the wall of the first reservoir 5 in which the transfer pipe 3 is positioned. The debris deflector plate 22 extends across the entire breadth of the first reservoir 5. The debris deflector plate 22 extends to above the level of the overflow pipe 16, and extends to below the transfer pipe 3. The debris deflector plate is approximately 150mm deep, i.e. from top to bottom.

[0029] The transfer pipe 3 is the greywater inlet pipe for the second reservoir 35. The second reservoir 35 has potable water inlet apparatus 31 including a potable water pump 33 at the top of the second reservoir 35 and a water outlet pipe 27 together with a water outlet distribution pump 25 at the bottom of the second reservoir 35. High and low level proximity detectors 29, 23 are provided on the second reservoir 35. [0030] In use, when a hand basin is used, greywater drains from the basin and enters the top of the greywater inlet pipe 11. The greywater in the greywater inlet pipe 11 triggers the proximity detector 13, which activates the dosing process through the dosing reservoir 7 and the dosing pipe 9. The greywater in the greywater inlet pipe 11 is then dosed with bleach to a concentration of 5ppm of greywater.

[0031] The dosed greywater travels through the remainder of the greywater inlet pipe 11 and exits the greywater inlet pipe 11 through the opening 19. The greywater inlet pipe 11 enters the first reservoir 5 through its side wall and bends in such a way that the opening 19 points upwardly into the first reservoir 5. This allows the greywater to enter the first reservoir 5 gently, so as to minimise disturbance to greywater held in the first reservoir 5. After entering the first reservoir 5, the greywater is held in the first reservoir 5. The suspended solids in the greywater then begin to settle to the bottom of the first reservoir 5. [0032] The waste outlet pipe 21 and the solenoid valve 17 at the bottom of the first reservoir 5 purge the settled solids out of the first reservoir 5 to remove sediment buildup and therefore allow the water recycling device 1 to operate continuously. In this embodiment, the solenoid valve 17 opens every 48 hours for a time period of 45 seconds.

[0033] The overflow pipe 16 and the non-return valve 15 at the top of the first reservoir 5 provide a safety measure and ensure that the water recycling device 1 continues to function even at a high greywater input flow rate.

[0034] When the greywater level in the first reservoir 5 reaches a sufficient level, settled greywater leaves the first reservoir 5 through the transfer pipe 3 and is transferred to the second reservoir 35. In this embodiment, the transfer pipe 3 has a diameter of 1.5 inches (3.81 cm) . The transfer pipe 3 is positioned so that water begins to flow out of the first reservoir 5 and into the second reservoir 35 when the liquid volume in the first reservoir reaches 65 litres.

[0035] In the second reservoir 35, the settled greywater mixes with potable water, which enters the second reservoir 35 through the potable water inlet apparatus 31 at the top of the second reservoir 35, pumped by the potable water pump 33.

[0036] The mixed, settled greywater in the second reservoir 35 leaves the second reservoir 35 through the water outlet pipe 27, pumped by the water outlet distribution pump 25. This mixed greywater is pumped into the water tank or cistern of a toilet or urinal. The water outlet pipe 27 has a preferred diameter of 1.5 cm.

5 [0037] The high and low level proximity detectors 29, 23 together with the potable water pump and apparatus 33, 31 and the water outlet distribution pump 25 control the level of water in the second reservoir 35. For example, if the low level proximity detector 23 is triggered, the water outlet

10 distribution pump 25 is deactivated and potable water allowed to enter the second reservoir 35 from the potable water apparatus 31 to allow for the water level in the second reservoir 35 to increase. This prevents the water outlet distribution pump 25 running dry, which would damage the pump

15 25.

[0038] Alternatively, if the high level proximity detector 29 is triggered then the potable water pump and apparatus 33, 31 deactivate to allow for the liquid level in the second 20 reservoir 35 to decrease. In this embodiment, the liquid volume in the second reservoir 35 is held at or around 24 litres .

[0039] When in use, the discharge of mixed potable and 25 greywater out of the second reservoir 35 is controlled by the discharge of water from the water tank or cistern of a toilet or urinal which is supplied with water by the device of the present invention. For example, a ball valve in the water tank of a toilet that is supplied by the device will 30 close when the cistern is full. This causes the water pressure in the water outlet pipe 27 to build. At a pressure of 1.5 bar, the water outlet distribution pump 25 shuts off. When a toilet or urinal is flushed and the ball valve in the cistern opens, the pressure drops and the water outlet 35 distribution pump 25 switches back on to fill the cistern back up with mixed potable and greywater.

[0040] There is an over pressure switch set at 3 bar, in series .

[0041] It will be understood that the embodiments illustrated above show applications of the invention only for the purposes of illustration. In practice the invention may be applied to many different configurations, the detailed embodiments being straightforward for those skilled in the art to implement.

Claims

1. A water recycling device for use in a communal bathroom, comprising:

a greywater inlet pipe through which greywater enters the first reservoir at or towards the bottom of the first reservoir;

a second reservoir for receiving greywater from the first reservoir from which at least some suspended solids have been removed, and in which the greywater may be mixed with potable water; and

2. A water recycling device according to claim 1, wherein the first reservoir has a capacity of from 50 to 75 litres .

3. A water recycling device according to claim 1 or 2 wherein the greywater inlet pipe enters the first reservoir in an upwardly direction.

4. A water recycling device according to claim 1, 2 or 3, wherein the greywater inlet pipe is inclined vertically from the horizontal as it enters the first reservoir.

5. A water recycling device according to any preceding claim, wherein the greywater inlet pipe is substantially upright as it enters the first reservoir.

6. A water recycling device according to any preceding claim, wherein the greywater inlet pipe enters the first reservoir through a side wall of the reservoir.

5 7. A water recycling device according to any of claims

1 to 5, wherein the greywater inlet pipe enters the first reservoir through the floor of the first reservoir in a substantially upright direction.

10 8. A water recycling device according to any preceding claim, wherein the greywater inlet pipe further comprises a dosing pipe for dosing the greywater passing through the greywater inlet pipe with a chemical agent.

15 9. A water recycling device according to claim 8, wherein the dosing agent is a cleansing or purifying agent.

10. A water recycling device according to claims 8 or 9, wherein the dosing agent is bleach.

20

11. A water recycling device according to any of claims 8 to 10, wherein the dosing is triggered by a proximity sensor .

25 12. A water recycling device according to any of claims

8 to 11, further comprising a chemical agent reservoir connected to the dosing pipe.

13. A water recycling device according to any of claims

30 8 to 12, wherein the dose of chemical agent is from 1 to lOppm of greywater.

14. A water recycling device according to claim 13, wherein the dose of chemical agent is 5ppm of greywater.

35

15. A water recycling device according to any preceding claim, wherein the waste outlet valve comprises a solenoid valve .

5 16. A water recycling device according to claim 15, wherein the valve is automatically controlled to open and close at regular intervals for a predetermined period of time .

10 17. A water recycling device according to claim 16, wherein the waste outlet valve opens once every 48 hours.

18. A water recycling device according to any of claims 15 to 17, wherein the waste outlet valve is opened from 30

15 to 60 seconds at a time.

19. A water recycling device according to claim 18, wherein the waste outlet valve is opened for 45 seconds at a time.

20

20. A water recycling device according to any preceding claim, wherein the first reservoir further comprises transfer means for transferring settled greywater from the first reservoir to the second reservoir.

25

21. A water recycling device according to claim 20, wherein the transfer means is positioned such that the greywater in the first reservoir must reach a volume of from 50 to 75 litres before transfer to the second reservoir

30 occurs.

22. A water recycling device according to claim 21, wherein the transfer means is positioned such that the greywater in the first reservoir must reach a volume of from

35 60 to 70 litres before transfer to the second reservoir occurs .

23. A water recycling device according to claim 22, wherein the transfer means is positioned such that the

5 greywater in the first reservoir must reach a volume of substantially 65 litres before transfer to the second reservoir occurs.

24. A water recycling device according to any preceding 10 claim which further comprises a debris deflector plate positioned so as to prevent floating solids from passing from the first reservoir into the second reservoir.

25. A water recycling device according to any preceding 15 claim, wherein the second reservoir has a capacity of from

50 to 75 litres.

26. A water recycling device according to any preceding claim, wherein the second reservoir further comprises potable

20 water inlet apparatus.

27. A water recycling device according to claim 26, wherein the potable water inlet apparatus enters the second reservoir at or towards the top of the reservoir.

25

28. A water recycling device according any preceding claim, wherein the water outlet comprises a distribution pump .

30 29. A water recycling device according any preceding claim, wherein the water recycling device further comprises water level control means for controlling the water level in the second reservoir.

35 30. A water recycling device according to claim 29, wherein the control means further comprises low level and/or high level proximity detectors.

31. A water recycling device according to claim 29, 5 arranged such that when the lower proximity detector detects the water level as being at a predetermined minimum level, potable water can enter the second reservoir and water is prevented from leaving the second reservoir through the water outlet .

10

32. A water recycling device according to claim 31, arranged such that water is prevented from leaving the second reservoir by cutting power to the water outlet distribution pump .

15

33. A water recycling device according to claim 32, arranged such that when the upper proximity detector detects the water level as being at a predetermined upper level potable water is stopped from entering the second reservoir

20 and water is permitted to leave the reservoir through the water outlet.

34. A water recycling device according to any of claims 30 to 33, arranged such that volume of water in the second

25 reservoir is held between 20 and 30 litres.

35. A water recycling device according to claim 34, wherein the water level is held at substantially 24 litres.

30 36. A water recycling device according to any preceding claim, wherein discharge of mixed potable and greywater out of the second reservoir is controlled in response to the discharge of water from a cistern of a toilet or urinal in combination with the water outlet.

35

37. A water recycling device according to claim 36, wherein the water outlet distribution pump shuts off when a predetermined pressure in the pipe is reached.

5 38. A water recycling device according to claim 37, wherein the predetermined pressure is 1.5 bar.

39. A water recycling device according to any of claims 36 to 38, arranged such that when the pressure drops below

10 a predetermined pressure, the water outlet distribution pump switches on.

40. A water recycling device according any preceding claim which runs on 24 volts.

15

41. A water recycling device according to any preceding claim for use in recycling water from 4 to 8 sinks in a communal bathroom.

20 42. A water recycling device according to any preceding claim for use in providing recycled water to 4 to 8 toilets and/or urinals in a communal bathroom.

43. A method for recycling water for use in a communal

25 bathroom, the method comprising the steps of:

receiving and holding greywater in a first reservoir to allow suspended solids in the greywater to settle at the bottom of the first reservoir, the greywater entering the first reservoir through a greywater inlet pipe at or towards 30 the bottom of the first reservoir;

purging settled solids from the first reservoir through a waste outlet;

receiving greywater from which at least some suspended solids have been removed in a second reservoir from 35 the first reservoir; mixing the greywater with potable water in the second reservoir; and

5

44. The method for recycling water for use in a communal bathroom according to claim 43, wherein the method is performed using a device as described in any preceding claim.

10 45. A water recycling device substantially as hereinbefore described with reference to the accompanying drawings .

46. A method for recycling water substantially as

15 hereinbefore described with reference to the accompanying drawings .