NZ540237A - Liquid storage assembly - Google Patents

Abstract

A liquid storage assembly (1) comprising, a liquid delivery conduit (3), an expandable liquid storage container (6) arranged to receive liquid from the liquid delivery conduit (3), and bypass means (9) arranged to direct liquid from the liquid delivery conduit away from the expanadable liquid storage container when it has attained a predetermined degree of expansion.

Description

54 7 ? "7 WO 2004/053242 PCT/AU2003/001607 LIQUID STORAGE ASSEMBLY Field of the Invention This invention relates to a liquid storage assembly. It particularly relates to a liquid storage assembly for storing rainwater and/or gray water.

Background of the Invention With growing world population there is an ever increasing need for fresh water. Unfortunately, in arid countries such as Australia the amount of rain fall which provides the necessary fresh water is in some instances inadequate, particularly in drought years.

Despite a lack of fresh water resources, a large amount of useable fresh water, such as water from domestic baths and showers, is lost through being flushed down sewerage lines. Apart from presenting problems of disposal, the water could much more usefully be used for a range of useful purposes such as watering domestic gardens, 20 etc.

In addition, much rainwater is lost through stormwater drains. In times of heavy rain, the disposal of rainwater through stormwater drains can be problematic leading to localised flooding in the most extreme instances. Again, this wasted water could 25 more profitably be used for domestic or other purposes if it could be stored rather than being allowed to run away down the drains.

Thus, there is a need for a storage system which is suitable for storing gray water and/or rainwater. Furthermore, it is preferred that the storage system be one which is 30 relatively simple to construct, can be sited in locations where it is not an eyesore and can be readily accessible in times of need. 2 Disclosure of the Invention The invention provides in one aspect a liquid storage assembly comprising, a liquid delivery conduit, an expandable liquid storage container arranged to receive liquid from the liquid delivery conduit, and bypass means arranged to direct liquid from the liquid delivery conduit away from the expandable liquid storage container when it has attained a predetermined degree of expansion.

The liquid stored in the liquid storage container may comprise rainwater, gray water, water from other sources and/or mixtures thereof.

The expandable liquid storage container may comprise a flexible bladder. It may be 15 formed from one or more sheets of plastics materials. The sheets may be single layer or multi-layer plastics.

In a preferred aspect of the invention, the liquid storage container may comprise two or more sheets of polypropylene. The sheets of polypropylene may have been 20 superimposed upon each other and heat welded at their edges to provide a sealed bladder.

The heat welding may be vacuum tested to ensure that its strength is at least as high of that the virgin polypropylene material.

The flexibility of the sheet material should enable the bladder to assume the shape of irregular surfaces upon which it may be laid. Furthermore, in its unfilled state such as when it is being installed, it may be rolled or folded such that it can pass through restricted openings before unfolding to assume its full capacity. Hence, it may be 30 installed underneath a house even if there is only a small access way.

There may be more than one liquid storage container in the liquid storage assembly. 3 Where there is more than one liquid storage container, the different liquid storage containers may be used for storing different liquids. For example, one storage container may be used to store rainwater. Another storage container may be used to 5 store gray water.

Outlets leading from the storage containers may be arranged so that differing amounts of liquid may be drained from the storage containers and mixed. Thus for example, it may be desirable to mix rainwater with gray water so as to dilute the gray water and 10 make it more suitable for use on gardens or other applications. Valves or other means may be provided to control the proportions of mixing.

A one-way valve may be provided in association with each expandable liquid storage container. The one-way valve may be arranged so as to allow liquid to enter the 15 storage container from the liquid delivery conduit whilst preventing it leaving the storage container in the reverse direction. It also reduces the likelihood that odour from the gray water enters the sub-floor space.

Typically the flexible storage bladders may range in size from 300 litres to as much 20 as 20,000 litres depending upon the space available and method of installation adopted. Where smaller bladders are used, a plurality of bladders may be combined to give a satisfactory storage capacity.

Preferred aspects of the invention will now be described with reference to the 25 accompanying drawings.

Brief Description of the Drawings Figure 1 shows an elevational view of a liquid storage assembly according to 30 the invention after it has been partially filled; Figure 2 shows an elevational view of the liquid storage assembly of Figure 1 after it has been filled; 4 Figure 3 shows an isometric view of support assemblies for the bladders used for the invention; Figure 4 shows an isometric view of a non-return valve fitted to a section of the bladder; Figure 5 shows the section A-A taken through the non-return valve shown in Figure 4; and Figure 6 shows a plan of the piping arrangements used for a liquid storage system using liquid storage assemblies according to the invention.

Detailed Description of the Preferred Embodiments The various elements identified by numerals in the drawings are listed in the following integer list.

Integer List 1 Liquid storage assembly 3 Inlet pipe Non-return valve 6 Expandable bladder 7 Angle pipe 9 Overflow hose 11 Outlet 13 Ground or floor Support assembly 17 Leg 19 Horizontal member 21 Supporting mesh 23 Footing 24 Storm water pipe T-connection 26a, 26b T-joint 28 Combined outlet Tubular member 32 Cross member 34 Sealing flap 36 Rod 38 Tension spring 40 Sealing ring 42a Expansion joint 46a Bypass 47a Upstand 48a Upstand 49a On-off valve 50b S-bend 51b Vent Referring to Figure 1, the liquid storage assembly shown therein is generally designated 1.

It includes an inlet pipe which may be connected to a source such as a stormwater 20 pipe or a source of gray water.

The liquid inlet pipe is tiltable so that it may assume the configuration where it is angled downwardly towards the bladder as shown in Figure 1 and may ultimately assume a configuration where it is tilted upwardly as shown in Figure 2, The inlet pipe 3 is connected to an angle pipe 7 which in turn connects to a non-return valve 5 fitted to an expandable bladder 6. The angle pipe also connects with an overflow hose 9.

The expandable bladder is fitted with one or more outlets 11 at the level of the ground or floor 13 on which the bladder rests. In this regard, the bladder may rest in a support assembly 15 which will be described in more detail hereinafter.

WO 2004/053242 PCT/AU2003/001607 6 As can be seen from the progression from Figure 1 to Figure 2, when the inlet pipe is initially angled downwardly water flows directly into the bladder 6 bypassing the overflow hose 9. However, as the bladder fills and expands in the manner shown in 5 Figure 2, it ultimately expands to a point where it can receive no more water ie. it has achieved a predetermined degree of expansion equal to its water carrying capacity. As a result, it accepts no further water and any water coming along pipe 3 will be directed out through the overflow pipe 9 or the pipe 3 may be bypassed.

Where the bladder is being used to store rainwater, it is anticipated that the arrangement will be such that the end of the inlet pipe 3 connected to the angle pipe will be raised so much by the expansion of the bladder that it points slightly upwards. Thus, any further rainwater, rather than flowing along the upward directed pipe, may bypass the inlet pipe 3 to allow the water to flow directly to a stormwater drain 15 without continuing to flow along the inlet pipe 3.

In an alternative arrangement involving gray water, it is anticipated that the inlet pipe 3 will be set so that it continues to slope downwardly, even when the bladder 6 has been filled. In such an arrangement, excess gray water will be diverted down the 20 overflow hose 9 which may be connected with a sewerage line.

Referring to Figure 3, there are shown two support assemblies 15 which are arranged to hold the liquid storage bladders 6 of the type described with reference to Figures 1 and 2.

As the bladders are suitably formed of a thin, flexible plastic material such as polypropylene it is preferred that the bladders be protected and supported by the support assembly both to prevent them moving out of position as a result of their flexibility and also to protect them against puncture by sharp objects which may be 30 lying on the ground. 7 Thus, the support assemblies comprise a frame in the form of legs 17 provided at the corners of the frame and joined by the horizontal members 19. The legs and horizontal members may be formed of any suitable material such as tubular steel.

A supporting mesh 21 is mounted on opposed horizontal members to provide opposed walls and a floor for protecting the expanded bladders and holding them rigidly in position. The supporting mesh may comprise any suitable flexible material such as canvas, geotextile fabric, felt, shade cloth etc.

The support assemblies may be constructed so that they can be readily dismantled and erected in places where they are out of sight and where there is little vertical clearance. Thus, they may be erected between the footings 23 supporting the floor of a house.

Referring to Figures 4 and 5, the non-return valve 5 shown in Figures 1 and 2 comprises a tubular member 30. A cross-member 32 extends diametrically across the interior of the tubular member and is attached to opposed walls thereof.

In turn, a rod 36 is secured to the cross member in such a manner as to allow it to 20 slide up and down with respect to the cross member. The opposite end of the rod 36 is connected to a sealing flap 34 which seals off the end of the tubular member mounted on the bladder 6.

A tension spring 38 is arranged to pull the sealing flap 34 upwards when there is no 25 downward water pressure through the tubular member.

In the presence of downward water pressure, the tension spring 38 expands to move the flap downwards and create an opening through which water may enter. Conversely, the tension in the spring has the effect of moving the sealing flap 30 upwards to seal the opening to the bladder and prevent any water in the bladder returning through the opening closed by the sealing flap. 8 A sealing ring 40 is provided around the interior of the tubular member. The sealing ring is arranged so it may provide a seal with the angled pipe 7 connecting to the nonreturn valve 5.

Referring to Figure 6, the arrangement shown therein envisages the use of two liquid storage assemblies in a system which mixes both rain and gray water to give a diluted form of gray water suitable for use such as watering gardens.

The reference numerals associated with the liquid storage assemblies include the 10 letter "a" after the reference numeral to denote stormwater and "b" to-denote gray water.

In the case of stormwater, a stormwater pipe 24a is connected to one or more inlet pipes 3a of the liquid storage assembly la via the non-return valve 5a. The T-15 connection 25a between the stormwater pipe 24a and inlet pipe 3a is arranged so that when the pipe 3a is, raised above a certain level by the expansion of the bladder 6a, water, rather than continuing to flow through pipe 3a passes along the pipe 24a to a stormwater drain. An expansion joint 42a may optionally be included in the inlet pipe 3a to accommodate movement of the inlet pipe as the bladder 6a fills.

The arrangement can be such that the diversion is accomplished simply by the action of gravity in relation to the variable height of the inlet pipe 3a as it moves with expansion of the bladder. However it is possible that the movement of the inlet pipe 3a may also be associated with some form of valving mechanism provided in the 25 T-connection 25a to close off the connection between pipe 24a and pipe 3a by virtue of a valve which closes and opens with varying movement of pipe 3a.

When a supply pipe 46a for stormwater is below the level of the bladders, the lower supply pipe can be joined to the stormwater pipe 24a by the upstands 47a and 48a. 30 An on-off valve 49a can be used to regulate water flow through the pipe 46a. The pipe 46a can be flushed out by opening the valve 49a periodically. 9 A parallel arrangement applies to the gray water storage assembly lb with the exception that there is no T-joint for diversion of liquid coming along the inlet pipe 3b. An overflow pipe 9b is arranged to direct all excess gray water to a sewerage system, in addition the inlet pipe 3b may include an S-bend 50b and vent 51b as is 5 known in the art. There may be one or more inlet pipes.

The outlets 1 la and 1 lb from the two expandable bladders 6a and 6b are connected through the valves 26a and 26b by the T-joint 27 to provide a combined outlet 28. The valves 26a and 26b can be set so that a desired ratio of stormwater to gray water 10 may be mixed to give a combined output of dilute gray water at an appropriate ratio which is acceptable to sewerage or other authorities.

Whilst the above description includes the preferred embodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions 15 may be introduced into the constructions and arrangements of parts previously described without departing from the essential features or the spirit or ambit of the invention.

It will be also understood that where the word "comprise", and variations such as 20 "comprises" and "comprising", are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

The reference to any prior art in this specification is not, and should not be taken as, 25 an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge in Australia.

Claims (13)

Claims

1. A liquid storage assembly comprising, a liquid delivery conduit, 5 an expandable liquid storage container arranged to receive liquid from the liquid delivery conduit, and bypass means arranged to direct liquid from the liquid delivery conduit away from the expandable liquid storage container when it has attained a predetermined degree of expansion. 10

2. A liquid storage assembly according to claim 1 wherein the liquid storage container comprises a flexible bladder.

3. A liquid storage assembly according to claim 1 or claim 2 wherein the liquid 15 storage container comprises at least one sheet of plastics material.

4. A liquid storage assembly according to any one of the preceding claims wherein the liquid delivery conduit is connected to a stormwater collecting system, and the liquid delivery conduit is directly connected to the expandable liquid storage 20 container and is constructed so that it is movable to accommodate expansion of the liquid storage container as it fills with liquid.

5. A liquid storage assembly according to any one of the preceding claims comprising a support assembly for supporting the expandable liquid storage 25 container.

6. A liquid storage assembly according to claim 5 wherein the support assembly comprises a flexible mesh material supported by a perimeter frame and the liquid delivery conduit includes a one way valve for preventing backwash of water from the 30 expandable liquid storage container. WO 2004/053242 11 PCT/AU2003/001607

7. A liquid storage assembly according to any one of the preceding claims comprising, a plurality of expandable liquid storage containers each arranged to receive liquid from a separate liquid delivery conduit, 5 supply means for each expandable liquid storage container, each of the supply means being arranged to drain liquid from the respective expandable liquid storage container, and mixing means for combining liquid drained from a plurality of the expandable liquid storage containers by the respective supply means. 10

8. A liquid storage assembly according to claim 7 comprising, a stormwater collecting system arranged to supply stormwater to one of the expandable liquid storage containers, and a gray water collecting system arranged to supply gray water to another of the 15 expandable liquid storage containers, wherein the mixing means is arranged to combine the gray water and stormwater in a predetermined proportion of gray water to storm water.

9. A liquid storage assembly according to any one of claims 1 to 6 wherein the 20 liquid delivery conduit is connected to a stormwater collecting system and a debris collection system is arranged to collect debris carried in liquid from the stormwater system such that the debris bypasses the liquid delivery conduit.

10. A liquid storage assembly according to any one of the preceding claims 25 located under a floor of a house.

11. A method of collecting and storing liquid comprising collecting liquid chosen from at least one of gray water and stormwater and storing the liquid in a liquid storage assembly according to claim 10. 30

12. A liquid storage assembly according to claim 1 substantially as hereinbefore described with reference to the accompanying drawings. WO 2004/053242 PCT/AU2003/001607 12

13. A method according to claim 11 substantially as hereinbefore described.