AU2021106894A4

AU2021106894A4 - Pneumatic Filtration System

Info

Publication number: AU2021106894A4
Application number: AU2021106894A
Authority: AU
Inventors: Steven De Clerck
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-08-24
Filing date: 2021-08-24
Publication date: 2021-11-25
Anticipated expiration: 2029-08-24
Also published as: AU2022221433A1

Abstract

A water filter for use in a pneumatic pumped water re-circulation system for a water body comprising: an inlet for water to be filtered to enter a filtration compartment and an outlet for filtered water to exit the filtration compartment; a filtration medium through which water to be filtered must pass through to exit the filtration compartment through the outlet, the filtration medium comprising at least a portion inclined from the vertical; wherein compressed gas is fed into water below the portion of filtration medium inclined from the vertical, causing bubbles of compressed gas to rise and migrate upwards along the inclined filtration medium causing contaminants in the water that are unable to pass through the filtration medium to move upwards along the filtration medium to be collected. 8/8 R22 70 22 10F 50 FIGURE 12

Description

8/8

R22 70 22

F

50

FIGURE 12

Pneumatic Filtration System

Field of the Invention

[0001] The present invention relates to a pneumatic system for filtering water of contaminants. More particularly, the present invention relates to a system of re-circulating water from and back into a body of water by a pneumatic water pump and filtering the recirculating water through a pneumatic water filter.

Background

[0002] Swimming pools, ponds, and other constructed or naturally occurring bodies of water commonly use conventional water pumps driven by an electric motor to re-circulate the water. These water re-circulation systems also often incorporate some form of filtration system to remove sand, leaves, and/or other undesirable contaminants. In some instances, chemicals may be introduced via the re-circulation or filtration system for maintaining, adjusting, or improving the physical characteristics or'quality' of the water for its intended purpose.

[0003] Electric motor-powered re-circulation systems and filters are relatively inefficient and costly to run. It would therefore be beneficial to provide more efficient means for recirculating and filtering water which reduce energy requirements as well as the time and costs associated with maintenance.

[0004] The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was part of the common general knowledge as at the priority date of the application.

[0005] Throughout the specification unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

[0006] Throughout the specification unless the context requires otherwise, the word "include" or variations such as "includes" or "including", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Summary of the Invention

[0007] According to a first aspect of the invention there is provided a pneumatic water pump for use in pumping water in a water body or re-circulating water from a water body, the water pump comprising:

a water conduit comprising a riser portion;

the riser portion comprising a top; and

compressed gas is fed into water in the riser,

wherein the compressed gas mixes with the water decreasing the density of the water causing it to rise towards the top.

[0008] The water body preferably comprises a natural pool, a chlorine or salt water or magnesium concentrated pool, a pond, lake, or another naturally occurring body of water or human constructed apparatus for holding water. The water body may also comprise a water body used in aquaculture.

[0009] In a preferred embodiment, the riser portion preferably comprises a substantially vertical portion of conduit. The top of the riser is preferably located above the base of the riser. The riser is preferably at least 1 m in length and preferably comprises a diameter of at least 50 mm. The riser preferably comprises a base and the compressed gas is fed into the base.

[0010] In a preferred embodiment, the compressed gas is compressed air although other compressed gases may be used.

[0011] The water conduit is filled with water and preferably an inlet portion of the water conduit supplies water to the base of the riser. The top of the riser preferably comprises an outlet portion through which water pumped through the riser can exit. The inlet portion of water conduit preferably comprises the same or larger diameter than the diameter of the riser. This may assist in reducing resistance at the inlet portion of the water conduit of the pneumatic water pump.

[0012] The outlet portion preferably comprises one or more air outlets for air to escape the water. A bend in the water conduit is preferably located between the top of the riser and the outlet portion. The bend preferably comprises an elbow joint. The outlet portion of the water conduit adjacent the bend is preferably substantially horizontal and comprises at least one outlet for air to escape the water. The one or more junctions preferably comprise T-junctions.

[0013] In a preferred embodiment, the water pump is removably installed in a separate compartment, box or pipe adjacent to the water body. The separate compartment, box or pipe is preferably fluidly connected with the water body.

[0014] According to a second aspect of the invention there is provided a water filter comprising:

an inlet for water to be filtered to enter a filtration compartment and an outlet for filtered water to exit the filtration compartment;

a filtration medium through which water to be filtered must pass through to exit the filtration compartment through the outlet, the filtration medium comprising at least a portion inclined from the vertical;

wherein compressed gas is fed into water below the portion of filtration medium inclined from the vertical, causing bubbles of compressed gas to rise and migrate upwards along the inclined filtration medium causing contaminants in the water that are unable to pass through the filtration medium to move upwards along the filtration medium to be collected. The bubbles of compressed gas also preferably cause contaminants of sufficiently small size that are able to pass through the filtration medium to move upwards and through the filtration medium.

[0015] Moving contaminants unable to pass through the filtration medium upwards along the filtration medium provides the benefit of reducing blockage of the filtration medium by contaminants and/or minimises a reduction in the flow rate of water through the filtration medium over time.

[0016] In a preferred embodiment, the water filter is for filtering the water of a water body comprising a natural pool, a chlorine or salt water or magnesium concentrated pool, a pond, lake, or another naturally occurring body of water or human constructed apparatus for holding water.

[0017] The inclined portion of the filtration medium preferably substantially faces the inlet whether the inlet is on a side or a surface of the base of the filtration compartment. In another preferred embodiment, the inclined portion of the filtration medium faces substantially side on to the inlet. The inclined portion is preferably at an angle of incline of between approximately 20 to 60 degrees from the vertical. The inclined portion is preferably at an angle of incline of approximately 30 degrees from the vertical. The person skilled in the art would readily appreciate that the angle of incline may vary based on the individual requirements of a user, and therefore, the angle may be within the range of 85 to 5 degrees from the vertical, however, such extreme angles will likely result in a reduction of efficiency of the water filter of the invention.

[0018] In a preferred embodiment, a substantial portion or all of the filtration medium is inclined from the vertical. The filtration medium preferably comprises apertures through which water can pass. These apertures are preferably regularly spaced and sized although alternative patterns and varying sizes are possible. The filtration medium preferably comprises apertures in the inclined portion, and more preferably throughout the inclined portion. Diameters of the apertures in the filtration medium preferably range between approximately 50 to 500 microns.

[0019] In a preferred embodiment, the filtration medium comprises apertures that increase in diameter from one side of the filtration medium to the other (inlet facing to outlet facing) to improve flow rate of the water through the filtration medium while also minimising the size of contaminants that can pass through the filtration medium.

[0020] The filtration medium preferably comprises a mesh screen. More preferably, the mesh screen comprises a wedge wire screen or preferably a flat wedge wire screen. The filtration medium is preferably removable for cleaning and maintenance, and/or replaceable.

[0021] In a preferred embodiment, compressed gas is continuously fed into water below the portion of filtration medium. The compressed gas preferably comprises compressed air and the compressed gas is preferably fed into water below the incline portion of filtration medium from at least one pipe. The pipe preferably comprises holes for the compressed gas to escape the pipe. The holes in the pipe are preferably regularly spaced and more preferably located close together, wherein the compressed gas escaping the pipe through the holes preferably form a curtain of rising bubbles. The holes in the pipe are preferably fine holes of approximately 0.1 mm to 5 mm, more preferably 0.5 mm to 2 mm, and most preferably between approximately 0.5 mm to 1 mm in diameter.

[0022] The compressed gas preferably mixes with the water into which it is fed therein decreasing the density of the resulting gas-water mixture causing it to rise along the lower incline of the filtration medium towards the top. At least a portion of the pipe comprising the holes for the compressed gas to escape is substantially horizontally aligned with the at least portion of the filtration medium inclined from the vertical. At least a portion of the pipe comprising holes for the compressed gas to escape is preferably also substantially horizontally aligned with and adjacent a base or lower edge of the inclined portion of the filtration medium.

[0023] The contaminants moved upwards by the bubbles of compressed gas preferably comprise leaves, other organic matter, insects, plastic, paper, and/or contaminants that are typically less dense than the water.

[0024] The filtration medium preferably comprises an upper edge and the contaminants that have migrated upwards to the upper edge can be collected from the water.

[0025] In a preferred embodiment, the air bubbles create a flow of water at the upper edge moving the contaminants away from the filtration medium and into a collection chamber. The collection chamber preferably comprises a bag, basket or fine mesh basket which can be removed from the collection chamber and emptied to dispose of the contaminants that enter the collection chamber. The basket or bag may vary in size based on the water body being filtered, the expected amount of contaminants that may be collected, and the desired frequency of maintenance.

[0026] The filtration compartment preferably comprises one or more plates spaced apart from the filtration medium to define a channel wherein the turbulence of the water containing contaminants flowing through the channel is reduced than in the absence of the one or more plates. The one or more plates are preferably positioned at approximately the same incline from the vertical as the filtration medium. Alternatively, an angle of the one or more plates may be at a different angle from the vertical than that of the filtration medium.

[0027] The reduced turbulence of the water also preferably assists to retain contaminants in the collection chamber for collection.

[0028] One or more plates may also be temporarily located or adjustable or moveable between the filtration medium and the outlet to temporarily prevent flow of water from the inlet to the outlet to allow for cleaning and maintenance of the water filter as required.

[0029] One or more brushes, Japanese mats, or other filter medium may also be removably positioned within the filter compartment and/or within the collection chamber to assist in removal of the contaminants.

[0030] In an alternative embodiment, water from the outlet exiting the filtration compartment enters a second filtration compartment comprising a second filtration medium. The second filtration medium is preferably positioned substantially horizontal although other configurations may be used.

[0031] Compressed gas is preferably fed into the water below the second filtration medium releasing bubbles causing water to rise through the second filtration medium trapping remaining contaminants in the water in the second filtration medium. Water that has passed through the second filtration medium can exit a second outlet in the second filtration compartment.

[0032] The second filtration medium is preferably removable for cleaning or replacing.

[0033] Compressed gas is preferably continuously fed into water below the second filtration medium. The compressed gas preferably comprises compressed air. The compressed gas is preferably fed into water below the second filtration medium from at least one pipe. The pipe preferably comprises holes for the compressed gas to escape the pipe. The holes in the pipe are preferably regularly spaced. The holes in the pipe are preferably fine holes of approximately 0.5 mm to 1 mm in diameter. The compressed gas escaping the pipe through the holes preferably forms a curtain of rising bubbles.

[0034] The pipe in the filtration compartment is preferably connected to the pipe in the second filtration compartment to supply the pipes with compressed gas from a single source.

[0035] The second filtration medium may comprise a variety of different mediums for filtering and/or decontaminating water and will depend on the type of water being filtered. The second filtration medium is preferably different to the filtration medium. The person skilled in the art would readily appreciate that there are a plurality of different additives, types and/or styles of second filtration mediums which may be used in the present invention and according to the type of water being filtered. Water from a natural body of water will not utilise chemicals in the second filtration medium.

[0036] In one embodiment, the second filtration medium for filtering water from a natural body of water comprises a biological filter medium. The biological filter medium preferably comprises bio balls or active carbon or charcoal.

[0037] In an embodiment of the invention for use in natural pools or other natural water bodies, the filtration compartment and/or second filtration compartment comprises at least one UV light source capable of killing or inactivating microorganisms (such as algae) in the water. The UV light source is preferably directed to the water exiting the outlet and/or the second outlet.

[0038] In an embodiment of the invention for a non-natural water body, the filtration compartment and/or second filtration compartment comprises at least one water chlorinator for chlorinating the water. The at least one water chlorinator preferably chlorinates the water exiting the outlet and/or the second outlet.

[0039] In an embodiment of the invention for a non-natural water body, the filtration compartment and/or second filtration compartment comprises one or more sources of chemicals for disinfecting and/or clarifying the water.

[0040] In embodiment of the invention, the filtration compartment and the second filtration compartment comprise a base, and the base comprises one or more sloping portions which lead to at least one drain or lower collection chamber where sediment in the water can collect and be removed from the filtration compartment and/or the second filtration compartment. A sediment collection pipe is preferably attached to the at least one drain through which sediment can pass to be collected in a drainage pit. The sediment collection pipe preferably comprises a valve (preferably adjacent the drainage pit) to prevent flow when not cleaning the filter.

[0041] According to a third aspect of the invention there is provided a water re circulation system for a water body comprising a water conduit, the water conduit comprising at least one pneumatic water pump as described herein. The water re-circulation system may be located within, adjacent, or located separate (but connected by water conduits) to the water body.

[0042] According to a fourth aspect of the invention there is provided a water re-circulation system for a water body comprising a water conduit, the water conduit comprising at least one pneumatic water pump as described herein, and at least one water filter as described herein.

[0043] Water from the water body is preferably pumped through the water conduit by the at least one pneumatic water pump. Water pumped through the water conduit from the water body preferably passes through the water filter and is filtered before passing through the pneumatic water pump and back into the water body.

[0044] The water conduit preferably comprises a water conduit inlet for the water from the water body to enter the water conduit. The water re-circulation system in one embodiment comprises a skimmer attached to the water conduit inlet. The skimmer preferably comprises an upward oriented opening at or adjacent to the surface of the water body for skimming debris and contaminants on and/or near the surface of the water body.

[0045] In an alternative embodiment, an additional pneumatic water pump as described herein may be connected intermediate the water filter inlet and the skimmer. The additional pneumatic water pump may be driven by a shared source of compressed air or have an independent source of compressed air. The additional pneumatic pump may be the same size, larger or smaller than the other pneumatic pumps depending on the type of body of water and the debris and contaminants expected to be encountered.

[0046] The invention further provides a kit for use in pumping the water of a water body, the kit comprising: at least a riser tube, an air injection assembly couplable to the riser tube and a compressed air source.

[0047] The invention further provides a kit for use in filtering the water of a water body, the kit comprising: a water filter comprising recesses or retaining means affixed to or integrally formed therein for mounting each of the following: one or more filtration medium, one or more perforated pipes couplable with an air source, and a basket or bag for collection of contaminants.

[0048] The invention further provides a process for the manufacture of a pneumatic water pump or a water filter or a water re-circulation system according to the invention as described herein.

Brief Description of Figures

[0049] The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a vertical cross section of the pump of the filtration system according to an embodiment of the present invention;

Figure 2 is a horizontal cross section of the pump of Figure 1;

Figure 3 is a horizontal cross section of a water filter of the filtration system according to an embodiment of the present invention;

Figure 4 is a flow diagram through the water filter of Figure 3;

Figure 5 is a side view of the water filter of Figures 3 and 4;

Figure 5A is a flow diagram of the sieve box version of the water filter;

Figure 5B is a flow diagram of the water filter of Figures 3, 4 and 5;

Figure 6 is a plan view of the filtration system of a pool according to an embodiment of the present invention;

Figure 7 is a plan view of the filtration system of a pool according to an alternative embodiment of the present invention;

Figure 8 is a plan view of the filtration system of a pool according to a further alternative embodiment of the present invention;

Figure 9 is a plan view of the filtration system of a pool according to a further alternative embodiment of the present invention;

Figure 10 is a side view of a system according to an embodiment of the present invention;

Figure 11 is a flow diagram of an alternative water filter according to an embodiment of the present invention; and

Figure 12 is a side view of a system according to an embodiment of the present invention.

Description of Preferred Embodiments

[0050] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features, compositions and compounds referred to or indicated in the specification, individually or collectively and any and all combinations or any two or more of the steps or features.

[0051] The present invention is not to be limited in scope by the specific embodiments described herein, which are intended for the purpose of exemplification only. Functionally equivalent products, compositions and methods are clearly within the scope of the invention as described herein.

[0052] Other definitions for selected terms used herein may be found within the detailed description of the invention and apply throughout. Unless otherwise defined, all other scientific and technical terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the invention belongs.

[0053] It will be appreciated that the indefinite articles "a" and "an" are not to be read as singular indefinite articles or as otherwise excluding more than one or more than a single subject to which the indefinite article refers.

[0054] Reference to cited material or information contained in the text should not be understood as a concession that the material or information was part of the common general knowledge or was known in Australia or any other country.

[0055] Each document, reference, patent application or patent cited in this text is expressly incorporated herein in their entirety by reference, which means that it should be read and considered by the reader as part of this text. That the document, reference, patent application, or patent cited in this text is not repeated in this text is merely for reasons for conciseness.

[0056] Throughout the specification and claims, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

[0057] Features of the invention will now be discussed with reference to the following preferred embodiments.

[0058] In a first preferred embodiment, a pneumatic water re-circulation system according to the invention comprises a pneumatic water pump for pumping water from a pool or another water body, and then re-circulating the water back into the pool after the water has been filtered and contaminants including debris removed.

[0059] Pneumatic Water Pump

[0060] In a preferred embodiment of the present invention, Figure 1 shows a vertical cross section of a pneumatic water pump 10, comprising a substantially vertically oriented riser tube 12 comprising a base 14 and a top 16. The riser tube 12 forms a portion of a re-circulation system for circulating water pumped from a pool 100 through a water filter 50 (described in detail below) before pumping the filtered water back into the pool 100 via the pneumatic water pump 10.

[0061] An air compression chamber housing 18 surrounds a portion of the lower end or base 14 of the riser tube 12. The housing 18 comprises a section of pipe with an inner diameter that is larger than the outer diameter of the riser tube 12 as shown in the riser tube 12 cross section of Figure 2. The housing 18 may further comprise an upper flange and a lower flange radially projecting inward towards the riser tube 12 for engaging with the base 14 of the riser tube 12 such that when engaged, define a space. The space between the housing 18 and the base 14 of the riser tube 12 forms an air compression chamber 20. The air compression chamber 20 may be assembled by coupling the air compression chamber housing 18 with the base 14 of the riser tube 12.

[0062] The air compression chamber 20 receives pressurised gas (air) from an air compressor 22 through an air supply pipe 24 coupled to a port on the housing 18. The air compression chamber 20 is configured to build up and maintain a threshold of pressurised air within the air compression chamber 20. The air compressor 22 may be positioned near or remote from the re-circulation system.

[0063] In the preferred embodiment, the base 14 of the riser tube 12 comprises a plurality of small apertures in the form of air holes of approximately 0.5 to 1 mm diameter or less and spaced approximately 1 cm apart. The pressurised air within the air compression chamber 20 is injected or released into the air compression chamber through the air holes (acting as a diffuser) forming fine, relatively evenly distributed bubbles in the water within the base 14 of the riser tube 12. The compressed air mixes with the surrounding water adjacent the base 14 of the riser tube 12 reducing the density (and average specific gravity) of this surrounding water causing it to rise within the riser tube 12. To a lesser degree, buoyant forces raising the formed air bubbles in an upwards direction through the water in the riser tube 12 also causes some movement of water under the buoyancy effect in the same direction (sometimes referred to as a two phase flow). The person skilled in the art would readily appreciate that there are a number of points along the riser tube 12 and adjacent the riser tube 12 where pressurised air may be injected or released so as to cause the resulting air water mixture of lower density than surrounding water to rise within the riser tube 12.

[0064] Preferably, the riser tube comprises a diameter of at least 50 mm however, this is subject to the flow required. Preferably, the air supply pipe 24 comprises a diameter of at least 16 mm, however, this is subject to the flow required. The air supply pipe 24 is attached to the riser tube 12 by one or more pipe clips 26. The one or more pipe clips 26 may assist reducing/eliminating stresses on the elbow connection to the compression chamber preventing leaks. In alternative embodiments and subject to the sizing and dimensions of the system, the air supply pipe 24 may be rigid such that pipe clips 26 or other means may not be necessary. The sizing of each may also be dependent on the amount of water to be recirculated. The person skilled in the art would appreciate and understand a variety of other attachment and fastening means may also be suitable for joining the air supply pipe 24 to the riser tube 12.

[0065] The pneumatic water pump 10 also comprises a section of pipe which changes the direction of flow, such as an elbow 28 positioned at or coupled to the top 16 of the riser tube 12. The elbow 28 alters the direction of the flow of water being pumped by the pneumatic water pump 10 vertically through the riser tube 12 to a substantially horizontal flow of water to direct the water back into the pool 100.

[0066] The pneumatic water pump 10 may also comprise one or more junction pipe sections 30 positioned following the elbow 28. The one or more junction pipe sections 30 provide a vent 32 in the form of an opening for air bubbles to escape the horizontal flow of water. This is important because if the air bubbles do not escape the water flow, they can potentially form air pockets downstream in the re-circulation conduit thereby blocking or reducing the water flow and the effect and/or efficiency of the pneumatic water pump 10. Venting of the air from the pneumatic water pump 10 may also reduce bubbles on the surface of the pool 100 which may provide a less turbulent flow and therefore a more aesthetically pleasing visual.

[0067] The re-circulation system comprises a water inlet pipe which is joined to the base 14 of the riser tube 12 from which water from the pool 100 or from the water filter is supplied to the riser tube 12. The diameter of the water inlet pipe is preferably larger than the diameter of the riser tube 12 to minimise the resistance of the water that may affect the pump.

[0068] The pneumatic water pump 10 is submerged substantially vertical within or adjacent to the pool 100 such that the top 16 of the riser tube 12 is relatively higher than the base 14 of the riser tube 12. The pneumatic water pump 10 may also be submerged in a separate compartment adjacent to the pool 100 provided the fluid level in the compartment is substantially the same as the pool 100.

[0069] Referring to Figure 2 there is provided a horizontal cross section of an embodiment of the pneumatic water pump 10. There is seen the air compression chamber 20 within the air compression chamber housing 18 and base 14 of the riser tube 12. The base 14 of the riser tube 12 comprises a plurality of apertures 34 for injecting or releasing air inward of the riser tube 12. The plurality of apertures 34 define a choke point assisting in the build up of air pressure within the air compression chamber 20 and for throttling the air from the air compression chamber 20 for injection into the column of water adjacent the base 14 of the riser tube 12. The plurality of apertures 34 may be directed horizontally into the column of water within the base 14 of the riser tube 12. In an alternative embodiment, the plurality of apertures 34 may be oriented at an angle to a horizontal cross section of the riser tube 12. Preferably, the plurality of apertures are radially offset so as to prevent the convergence of relatively lower bubbles with relatively higher bubbles to create bubbles which are not fine air bubbles. In a further alternative embodiment, the plurality of apertures 34 may combine and/or alternate a horizontally oriented apertures with angularly oriented apertures either alternating or in groups or other patterns.

[0070] The plurality of apertures 34 may also be referred to, but not limited to, as ports, holes, openings, outlets and/or vents. Preferably, the plurality of apertures 34 is configured and arranged around the perimeter of the base 14 so as to allow the injection or release of fine air bubbles substantially evenly distributed throughout the column of water within the base 14 of the riser tube 12. As the water flows upward through the riser tube 12, the displaced water is replaced by newly filtered water from the outlet of the filtration box 50 (as seen in Figure 3) drawn into the riser tube 2 through the base 14.

[0071] In an alternative embodiment, the air compression chamber housing 18 and air compression chamber 10 may be a separate unit which couples or attaches to the base 14 of the riser tube 12. In such an embodiment, the plurality of apertures 34 would be formed in the inner wall of the compression chamber unit. This embodiment would allow the outer diameter of the base 14 and the riser tube 12 to be substantially the same.

[0072] Water Filter

[0073] The re-circulation system of the present invention further comprises a water filter 50 as shown in Figure 3. Within the re-circulation system, water flows from the pool 100 through the water filter 50 before entering the base 14 of the riser tube 12 of the pneumatic water pump 10 which directs the water back into the pool 100.

[0074] The water filter 50 as seen in Figure 3 comprises a water filter housing 52 having one or more filtration compartments (which also encompasses chambers, sections, or stages) intermediate one or more inlets 54 and one or more outlets 56. In the present embodiment, the water filter 50 comprises two inlets 54 and two outlets 56. Each of the outlets 56 is fluidly connected and provides water to one or more pneumatic water pumps 10 (as seen in Figures 6, 7 and 8). In the present embodiment, the outlets 56 are fluidly connected and provide water to a total of four pneumatic water pumps 10. However, the person skilled in the art would readily appreciate that the number and connection of the or each of the inlets 54 and the outlets 56 may vary, provided the or each of the inlets 54, the outlets 56 and the filtration medium itself can support a volumetric flow rate of water equivalent to at least the volumetric flow rate of water generated by the air being injected into the water filter 50 and/or the pneumatic water pump(s) 10.

[0075] Referring to Figures 3, 4 and 5, as water enters the inlets 54 of water filter 50 it undergoes a first stage of filtration within the first filtration compartment of the water filter 50 where the debris, such as leaves and including very fine particles, are removed from the water. The water filter 50 comprises a first perforated pipe 60 which is substantially horizontal and adjacent a base of a filtration medium comprising a screen 64. The screen 64 is positioned at an angle (of incline) from the vertical and that is an incline preferably in a direction towards the at least one inlet within the filtration compartment. Air is supplied from the air compressor 22 to the first perforated pipe 60 through an air supply pipe 62 for injecting or releasing fine air bubbles which rise through the water along the face of the screen 64 so as to cause a flow of water within the water filter 50 directed towards a collection chamber in the form of a basket 70 for collecting larger debris and other contaminants. Generally speaking, contaminants comprising debris and larger materials, typically being less dense than water, are forced up along the screen and separated close to the water surface 80, by the air bubbles. Debris and fine particulates are prevented from passing through the screen 64. The flow of water created from the injection or release of fine air bubbles is directed away from the screen 64 at or near the water level 80 within the water filter 50 causing the debris or material which is floating or near the water level 80 to move towards the basket 70. The constant flow of water towards the basket assists in retaining the debris once inside the basket 70.

[0076] Referring to Figures 4, 5, 5A and 5B, in some embodiments, the water filter 50 may also comprise one or more additional plates or screens 742, 744 placed at a similar angle to the screen 64 but spaced at a distance from the screen 64. These additional plates or screens 742, 744 create discrete flow channels, to assist in reducing turbulence in the first filtration compartment and may reduce the space for debris and other contaminants to move within the water filter 50.

[0077] In an alternative embodiment, the additional plate or screen 742 is permanently affixed to assist in creating a discrete flow channel and reducing turbulence in the first filtration compartment permanently. Additionally, the plate 744 may be temporarily added during the cleaning process (when the screen 64 is removed from the filter) so as to prevent contaminated water from proceeding through the filter 50 without passing through the screen 64.

[0078] The basket 70 may comprise a lip 72 which engages with or rests on a frame or portion of the water filter 50 or other support means so as to position and provide support for the basket 70. As such, the basket 70 may be removed, emptied and cleaned before replacing in the collection chamber of the water filter 50. The basket 70 may comprise a screen, mesh or sieve-like material which allows water to freely permeate through while retaining debris.

[0079] In alternative embodiments, the water filter 50 may comprise only a single filtration compartment first stage filtration as seen in Figure 5A. Accordingly, the water filter 50 may filter out the debris and other material as described above before the filtered water is pumped to one or more of the pneumatic water pumps 10. For ease of reference, this water filter 50 arrangement may be referred to as a 'sieve box'.

[0080] The water in the water filter 50 may freely pass through the screen 64 to proceed through additional filtration chambers or compartments. The water that proceeds to the additional filtration chambers or compartments is substantially free from larger debris and materials.

[0081] Referring generally to Figures 4, 5 and 5B, the water filter 50 may optionally further comprise at least a second filtration compartment 67 optionally having a portion of its base 58 having a plurality of second perforated pipes 66. Each of the perforated pipes inject fine air bubbles through apertures in the pipes 66 to mix with the surrounding water. The density of the surrounding water as it mixes with the air is reduced causing the water to rise. In an alternative embodiment, the water filter 50 may further comprise a plurality of filter media in or adjacent to the second filtration compartment 67 above the second perforated pipes 66. For example, the present embodiment comprises a second filtration medium in the form of two filter media pads 90 with biological filter media 92 supported by support members 94. The second filtration medium may also be used in the collection chamber. The filter media pads 90 may be the same type of filter media pad. Alternatively, the filter media pads 90 may be distinct and different types of filter pads. The filter media pads 90 are preferably fixed in position across the region of the second filtration compartment. The support members 94 may comprise a plurality of members which extend across the second filtration compartment of the water filter 50 above the second perforated pipes 66. The support members 94 may cross over each other to form a grate to support the filter media above without impeding the flow of water through the filter media. The filter media pads may be cut to a size so as to fit snugly within the water filter 50 above the second perforated pipes 66. Alternatively, they may be retained by a releasable latch or pin or other suitable cross members. The person skilled in the art would appreciate a number of ways in which the filter media can be releasably secured between the second and a third chamber (or more).

[0082] In alternative embodiments, there may only be a singular mesh filter media pad 90. In a further alternative embodiment, there may be multiple mesh filter media pads 90. Accordingly, the filter media may be tailored for the particular body of water which the re-circulation system is being used with. For example, pool 100 may require additional chemicals, such as chlorine, which may be introduced as the water passes through the filter media pad 90 whereas ponds may not require these additional chemicals. As seen in Figure 5B, the water filter 50 may comprise an outlet apparatus for further treatment of the water as it exits the at least one outlet 56. For example, the outlet apparatus 96 may be a UV light (for natural bodies of water) or a chlorinator (for non-natural bodies of water). Typically, the system will use biological filter media or chemicals depending on whether the body of water being circulated natural (biological filter media) or non-natural (comprising chemicals).

[0083] The second perforated pipes 66 release or inject fine air bubbles which mixes with the surrounding water decreasing the density of the surrounding water causing it to rise towards and through the filter media pads 90 and the biological filter media 92. Each of the outlets 56 of water filter 50 are fluidly connected to this section of the water filter 50. Accordingly, at least for the present embodiment, only water which has been filtered from debris as well as the filter media pads 90 and biological filter media 92 can flow through the outlets 56. In the sieve box arrangement, only water which has been filtered from debris and other materials can flow through the outlets 56.

[0084] Referring to Figure 4, there is provided a general flow diagram. The larger bolded arrows show the intended preferable flow of water through the water filter 50. The smaller arrows show the intended and preferable flow of air bubbles through the water filter 50. These flow patterns are shown for the purposes of example and may diverge or vary in reality.

[0085] With reference to Figure 11, there is provided an alternative water filter having one or more drains 152 which are fluidly connected to a drainage pit 154. The one or more drains 152 may be utilised in the water filter 50 as shown or in the sieve box configuration as mentioned above. Furthermore, the filtration compartment and/or the second filtration compartment may comprise one or more sloped base surfaces 156 for encouraging sediments and debris towards the one or more drains 152. The drainage pit 154 may be positioned for easy access to remove a build-up of sediment and/or to be cleaned.

[0086] Re-Circulation System

[0087] Referring to Figures 6, 7, and 8, there is provided three non-limiting alternative arrangements of the re-circulation system.

[0088] Figure 6 provides an embodiment of the re-circulation system in which water enters the system through the inlets 54 of the water filter 50 which are fluidly connected to two spaced apart openings positioned on one side of the pool 100.

[0089] After being filtered through the water filter 50 the filtered water is further pumped through the re-circulation system by the four pneumatic water pumps positioned at the opposite end of the pool 100 opposite where the water enters the recirculation conduit. Each of the pneumatic water pumps 1 pump the filtered water back into the pool 100 on the opposite side of where the water enters the re-circulation system.

[0090] Figure 7 shows an alternative embodiment of the re-circulation system, in which the water enters the re-circulation system, in part, from openings positioned at the bottom of the pool 100. The openings at the bottom of the pool

100 and the single opening on the side of the pool 100 are in fluid communication with the inlets 54 of the water filter 50. As can be seen in Figure 7, water may enter the re-circulation system from the opening in the wall of the pool 100 in combination with openings positioned on the bottom of the pool 100. This embodiment having opening positioned on the bottom of the pool may assist in the filtration and removal of denser debris from the pool 100. Furthermore, it may reduce/eliminate the need for vacuum cleaner equipment typically used in the pool 100. As this requires access to the bottom of the pool 100, this arrangement is more likely to be used during initial installations of a pool or other body of water as opposed to refurbishing an existing pool or other body of water.

[0091] Figure 8 shows a further alternative embodiment, where each end of the pool 100 has a re-circulation system installed. The re-circulation system comprising a water filter 50 and a pneumatic water pump 10 on each end of the pool. On one side of the pool 100, the water filter 50 (sieve box arrangement) and the pneumatic water pump 10 are fluidly connected with the pool. This arrangement will only re-circulate the water and filter out larger debris and other materials. On the other side of the pool 100, the water filter 50 and the pneumatic water pump 10 are in fluid connection with the pool. This arrangement will circulate the water, filter out larger debris and other materials and filter the water through the filter media pad or pads 90 and biological filter media 92 before providing the water to the pneumatic water pump 10 to be pumped back into the pool. The person skilled in the art would appreciate that the positioning of the water filter 50 and pneumatic water pump 10 may vary and their positioning in Figures 6, 7 and 8 are designed to source water which needs to be filtered as far from water that is being returned to the pool 100. However, they may also be positioned so as to create sufficient flow across the entire pool to assist in removal of debris. The location, size and number of the drains, water filter 50 and pumps is to be optimised on a case-by-case scenario.

[0092] Referring to Figure 10, the re-circulation system of the present invention for re-circulating water within a pool is gravitational. That is, the pool 100, pneumatic water pump(s) 10, water filter(s) 50 (which includes the water filter

(sieve box arrangement)) all need to operate at approximately the same water level. Accordingly, the water filter 50 and the pneumatic water pump 10 must be installed such that the desired water level is substantially level with the water level of the pool. Only small differences in water level, for example, up to - 10 cm are possible, as the air in the vertical pipe is not able to 'push' water higher than the water level within the pipes. As such, it is not possible to put the pneumatic water pump 10 in an above ground shed further away from the pool, as typically done with conventional pumps powered by an electrical motor, for ease of maintenance and noise reduction. On the other hand, there is no need to put the pneumatic water pump 10 away from the pool, provided there is sufficient room next to the pool, as virtually no noise is generated by the vertical pipe and virtually no maintenance is required. The only noise source for the system is the air compressor 22, which is typically much more silent than a conventional water pump and can be located further away from the pool, if desired.

[0093] The system may further comprise one or more skimmers 158 as can be seen in Figure 10. Each skimmer 158 has an opening directed upwards towards the surface of the body of water, such as pool 100, for receiving water having debris and/or contaminants to deliver to the water filter 50. The or each skimmer 158 may be used with the water filter 50 or sieve box 50 configuration.

[0094] Referring to Figure 12 there is provided an alternative embodiment of the present invention wherein there is a discrete pneumatic water pump 10 associated with the one or more skimmers skimmer 158. In this embodiment, the pneumatic water pump 10 is positioned intermediate the filter box 50 and the pool 100 or other water body. The water collected by the skimmer(s) 158 is pumped directly into the filter box 50.The discrete pneumatic water pump 10 associated with skimmer 158 should increase the efficacy of the skimmer 158 in performing its function of retrieving contaminants at or near the surface of the water body.

[0095] Figure 9 provides a further alternative embodiment of the system of the present invention wherein there is only a single pneumatic water pump 10 connected to the outlet 56 of the water filter 50. Additionally, there are three pneumatic water pumps 10 which are in separate and independent fluid circuits with the pool 100. In this embodiment, the pneumatic water pump 10 connected to the water filter 50 recirculates filtered water back into the pool 100. The remaining pneumatic water pumps 10 assist in moving the water of the pool 100 towards the openings at the other end of the pool 100 which provide water to the at least one inlet 54 of the water filter 50. Accordingly, the pneumatic water pumps 10 may be employed to help prevent settling of sediments within the pool 100 or other body of water or direct water towards one end of the pool, for example, to assist moving floating contaminants towards a skimmer. Keeping the sediments in a suspended state may improve the efficacy of the filtration system.

[0096] The pneumatic water pump 10 seeks to provide an efficient method of moving water or other fluid. The present invention provides a pneumatic water pump 10 within the re-circulation system which enables the movement of large quantities of water using a relatively small amount of power (when compared to electric motors typically used in conjunction with conventional water pumps). The sizing and/or number of pneumatic water pumps 10 and size of the water filter 50 required in each case will be determined on a case-by-case scenario.

[0097] Importantly, the present system can be altered to scale for a specific size of pool. For example, a larger pool may require a larger number of and/or larger pneumatic water pumps 10 and one or more water filters 50 can be employed on a single body of water. As mentioned above, the water filter 50 may be modified to meet the specific characteristics of the body of water being filtered. For example, some natural ponds may only require the sieve box 50 having the single filtration compartment whereas, a commercial or residential pool may require a water filter 50 which comprises the first and second filtration compartment. The configuration and number of components for each system will vary based on the specific requirements of the body of water.

[0098] While the above discussion refers to use in a pool, the present invention may be implemented in any suitable body of water which requires filtration. The present invention relates to a pneumatic filtration system which discusses pneumatic water pumps and pneumatic water filters. However, the present invention may be implemented using another suitable gas. The person skilled in the art would not limit the invention to exclusively use of compressed air.

[0099] Modifications may be made to the present invention within the context of that described and shown in the drawings. Such modifications are intended to form part of the invention described in this specification.

Claims

1. A pneumatic water pump for use in pumping water in a water body or re circulating water from a water body, the water pump comprising:

a water conduit comprising a riser portion;

the riser portion comprising a top; and

compressed gas is fed into water in the riser,

2. A water filter comprising:

wherein compressed gas is fed into water below the portion of filtration medium inclined from the vertical, causing bubbles of compressed gas to rise and migrate upwards along the inclined filtration medium causing contaminants in the water that are unable to pass through the filtration medium to move upwards along the filtration medium to be collected.

3. A water re-circulation system for a water body comprising a water conduit, the water conduit comprising at least one pneumatic water pump according to claim 1.

4. A water re-circulation system for a water body comprising a water conduit, the water conduit comprising at least one pneumatic water pump according to claim 1, and at least one water filter according to claim 2.

5. A pneumatic water pump according to claim 1, or a water re-circulation system for a water body according to claims 3 or 4, wherein the water body comprises a natural pool, a chlorine or salt water or magnesium concentrated pool, a pond, lake, or another naturally occurring body of water or human constructed apparatus for holding water.