WO2006105575A1

WO2006105575A1 - Water treatment apparatus

Info

Publication number: WO2006105575A1
Application number: PCT/AU2005/001580
Authority: WO
Inventors: Ian Geoffrey Cummins
Original assignee: Cumminscorp Ltd
Current assignee: Cumminscorp Ltd
Priority date: 2004-10-13
Filing date: 2005-10-13
Publication date: 2006-10-12
Anticipated expiration: 2007-04-13

Abstract

Water treatment apparatus (10) comprising a building (11) having a tank-like base (12) for containing water, a drum or screen filter (23), a first biological filter chamber (26) for receiving water from the drum or screen filter (23), a series of further chambers (43,50,51,52,53,54) in which water can undergo different water treatments, and at least one further biological filter chamber (58, 70).

Description

WATER TREATMENT APPARATUS Technical Field.

This invention relates to water treatment apparatus and in particular to apparatus for treating water for the purposes of purifying, cleaning or otherwise removing impurities or contaminants in the water. The present invention is particularly but not exclusively suited to treating contaminated bodies of water, grey water, sewerage or any other contaminated water. Background Art

The treating of water for the purposes of purifying the water or removing contaminants from water has become an increasing problem to growing communities where increasing volumes of effluent or contaminated water is generated. Contaminated . water can be generated in domestic, commercial and agricultural situations. Often such water receives primary treatment and is then simply left in settling ponds where solids settle out. With water shortages it is highly desirable that the contaminated water be treated so as to enable it to be reused or recycled. Summary of the Invention

The present invention aims to provide water treatment apparatus which is particularly suited to use treating and cleaning water in a range of different applications. Typical applications of the water treatment apparatus include applications for treating water in natural or artificial bodies of water such as lakes or dams, in aquaculture systems, aquariums, water tanks as well as grey water containers, tanks or reservoirs, and sewerage tanks or ponds or any other effluent tank or reservoir. Other objects and advantages of the invention will become apparent from the following description.

The present invention thus provides in one preferred aspect, water treatment apparatus comprising a building having a tank-like base for containing water, water treatment means within said building, a water inlet to said water treatment means, said water treatment means including a series of water-treatment chambers defined within said base and in which water can undergo different water treatments, and a water outlet for water treated by the water treatment means. The term "water" as used herein includes contaminated water or any other water or liquid carrying impurities or solids as well as water carrying sewerage and grey water.

The building preferably is a transportable building to enable it to be transported to any location where water requires treatment. The building suitably also comprises an enclosed building. Baffles or walls of any suitable configuration are suitably provided in the base to divide the base into the series of chambers. The series of chambers may be arranged in longitudinal alignment so as to be in one row. Alternatively the series of chambers may be arranged in more than one row adjacent to each other. Preferably the chambers are such that water flows in a serpentine manner through at least some of the chambers from one chamber to the next chamber so that the water remains for a sufficient time in the water treatment chambers.

The base may be of a rectangular configuration and a dividing baffle or wall may be provided in the base and centrally thereof with the series of chamber provided at least on one side of but preferably on opposite sides of the dividing baffle or wall. Other baffles, or walls may be provided to extend transversely of the dividing baffle to define individual chambers of the series of chambers. Outer walls of the chambers may be defined by outer walls of the base.

In a further configuration, the base may be of elongated rectangular configuration with opposite side walls of the base defining side walls of the series of chambers. Transverse side walls or baffles are suitably provided to divide the base into the series of chambers.

The water treatment means may include one or more screen filters. The water treatment means may also include means for exposing water to be treated to ozone. The water treatment means may also include means for exposing water to be treated to ultraviolet light. The water treatment means may also include means for exposing the water to bubbles of gas or air to separate impurities from the water. The water treatment means may also include at least one biological filter for biological treatment of water.

The water treatment means may comprise any combination of one or more of the above components. The components of the water treatment means are suitably associated with respective chambers of the series of chambers.

Preferably water from the water inlet is initially treated in a screen filter to remove solids from the water. The screen filter suitably comprises a drum filter. The drum filter suitably comprises a rotatable drum filter having a drum and a screen or mesh material about or on the periphery of the drum and means are provided for conveying water from the inlet to pass through the screen or mesh material. Suitably means are provided for supporting and rotating the drum. Such means may comprise motor means for causing rotation of the drum. Preferably however the drum is driven in rotation by water flowing into the drum. The drum is suitably supported externally for rotation. Preferably the water inlet is connected to or comprises a supply pipe which extends into the interior of the drum. The drum filter is suitably of one of the types disclosed in our aforementioned International patent applications. Other forms of drum filter however may be employed. Means may be provided for cleaning the screen or mesh material of the drum.

The means for cleaning the screen or mesh material may include means for spraying water and/or applying pressurized air onto the screen or mesh material. Suitably means within the drum are provided for collecting materials displaced from the screen or mesh material. The means for collecting the material may comprise a trough or channel supported within the drum. The trough or channel suitably extends in an axial direction within the drum.

The screen or drum filter may be supported over a first chamber of the series of chambers which collects water filtered by the screen or drum filter. The first chamber may also include a biological filter media supporting bacteria for biological treatment of . water filtered by the screen or drum filter. Preferably the first chamber includes a raised bottom wall for supporting the biological filter media. The raised bottom wall is suitably pervious to water. Typically the bottom wall comprises a perforated or grill-like panel. The bacteria carried by the media may comprise aerobic bacteria for removing ammonia and nitrites from the water or any other bacteria. Preferably agitating means are provided for selectively agitating the biological filter media. The agitating means may include a rotor and means for selectively driving said rotor for rotation. The driving means may comprise a motor of any form such as an electric or hydraulic motor.

The trough or channel for collecting materials displaced from the screen or mesh material or the screen or drum filter may direct those materials to a waste chamber of the series of chambers.

A plurality of further transverse baffles or walls extending substantially parallel to the first baffle or wall suitably define therebetween further chambers of the series of chambers. In a particularly preferred arrangement, a second chamber of the series of chambers may be provided adjacent the first chamber, the second chamber having an inlet for receipt of water to be treated and an outlet for treated water. A first common baffle or wall may be provided between the first chamber and the second chamber. The first baffle or wall may be arranged so that an inlet for water to the second chamber is provided at one end of the first baffle or wall. For this purposes, the first baffle or wall may be spaced at one end from a side wall of the base or through openings may be provided adjacent the one end of the first baffle. Alternatively the first baffle or wall may be arranged so that an inlet for water from the first chamber is provided under the first baffle or wall or through openings in a lower portion of the baffle. For this purpose, the bottom of the first baffle or wall may be spaced above a floor or bottom wall of the base. In another arrangement water from the first chamber may flow over the upper edge of the first baffle or wall or through apertures in the first baffle or wall into the second chamber. The second chamber may include one or more ultraviolet light sources such that water in the second chamber can be exposed to ultraviolet light. Ultraviolet light is suitably provided by one or more ultraviolet light sources within the chamber such as ultraviolet lamps fixed in the chamber.

The second chamber may also include means to selectively expose the water in the second chamber to ozone. Ozone from an ozone source such as an ozone reactor/s or generator/s may be supplied to the lower end of the chamber to bubble upwardly through that chamber. Ozone may be supplied to an air or gas block or blocks submerged in the second chamber or through another air outlet in the lower portion of the chamber.

The second chamber may also include means for selectively supplying air or gas to a lower portion of the chamber for bubbling through water therein. Air or gas may be supplied to one or more air blocks or outlets in a lower portion of the chamber.

Alternatively, the water for exposure to ozone and/or air may be directed to a third chamber through which ozone may be passed. A second common baffle or wall may be provided between the second chamber and the third chamber. The second baffle or wall may be arranged so that an inlet for water to the third chamber is provided at one end of the second baffle or wall which is opposite the one end of the first wall or baffle. For this purposes, the second baffle or wall may be spaced at its one end from a side wall in the base. Alternatively the second baffle or wall may be arranged so that an inlet for water from the second chamber is provided over the second baffle or wall. For this purpose, the top of the second baffle or wall may be below the top of the first baffle or wall so that the top of the second baffle or wall acts as a weir so that water flows downwardly against the flow of bubbles of ozone upwardly through the third chamber. In an alternative arrangement, water may flow under the second baffle or wall or through apertures in the second baffle or wall into the third chamber.

The third chamber may also include means for supplying air to a lower portion of the chamber for bubbling through water therein. Air may be supplied to one or more air blocks ^"or outlets in a lower portion of the chamber. A funnel, trap or skimmer may be provided at or adjacent the upper level of water in the chamber for collecting waste entrained in bubbles at the surface of the level of water. The funnel or trap member is suitably connected to waste for example a waste line.

A fourth chamber may be provided adjacent the third chamber to receive water from the third chamber. A third common baffle or wall may be provided between the third chamber and the fourth chamber. The third baffle or wall may be arranged so that an inlet for water to the fourth chamber is provided at one end of the third baffle or wall which is opposite the one end of the second baffle or wall. For this purposes, the third ^*baffle or wall may be spaced at its one end from a side wall of the base. Alternatively the third baffle or wall may be arranged so that an inlet for water from the third chamber is provided beneath the third baffle or wall. For this purpose, the bottom of the third baffle or wall may be above the floor of the base so that water flows beneath the third baffle. In an alternative arrangement, water may flow over the third baffle or wall or through apertures in the third baffle or wall into the fourth chamber. The fourth chamber may include means for exposing water therein to ultraviolet light. Preferably the fourth chamber includes one or more ultraviolet light sources. Alternatively the fourth chamber may be free of water treatment components.

A series of further chambers may be provided for further treatment of water. One or more of the series of further chambers may include means to expose water therein to ozone. One or more of the series of further chambers may include means to expose water therein to ultraviolet light.

A second biological treatment chamber may be provided to receive water from the second, third, fourth chamber or trailing chamber from the series of chambers. ^' A further transverse wall or baffle may separate the biological treatment chamber from the second, third, fourth or trailing chamber. The further baffle or wall may be arranged so that an inlet for water to the second biological treatment chamber is provided at one end of the third baffle or wall. For this purposes, the further baffle or wall may be spaced at its one end from a side wall in the main chamber. Alternatively the further baffle or wall may be arranged so that an inlet for water is provided over the further baffle or wall. For this purpose, the top of the further baffle or wall may be lowered so that the top of the further baffle or wall acts as a weir over which water flows. In another arrangement, water may flow under the further baffle or wall into the fourth chamber or through the further baffle or wall. The second biological treatment chamber may include a base wall or panel pervious to water through which water passing beneath or through the further baffle, or wall can flow upwardly into the second biological treatment chamber. The biological filter media is suitably supported on the pervious panel or wall. Agitating means as above may also be provided to agitate the filter media. The biological filter media may carry bacteria different to or the same as the bacteria carried in the first biological filter chamber. The bacteria may comprise anaerobic bacteria or any other bacteria.

One or more outlets may be provided communicating with the second biological treatment chamber through which treated water may pass. The treated water may be directed back to the body of water being treated or directed to a third biological treatment chamber. The one or more outlets may be provided at a lower end of the second biological treatment chamber where water is to be directed back to the body of water. Alternatively the one or more outlets may be provided at an upper end of the second biological treatment chamber and communicate with a third biological treatment chamber. Preferably the outlet or outlets- may communicate with means to distribute water from the second treatment chamber over the third biological treatment chamber. The distribution means suitably comprises a perforated pipe or pipes. Preferably the third biological treatment chamber includes a raised bottom wall or panel which is pervious to water and which supports biological filter media for carrying bacteria. The bacteria in the third biological treatment chamber may comprise aerobic bacteria or any other type or types of bacteria.

Preferably one or more water outlets are provided beneath the raised bottom wall or panel. . ^•

The waste chamber which receives waste from the drum filter may be provided adjacent to the second or third biological treatment chamber. A common transverse baffle . or wall may separate the second or third biological treatment chamber and waste chamber.

A filter chamber may be provided adjacent the waste chamber to receive water from the waste chamber. A common transverse baffle or wall may separate the waste chamber and filter chamber. Apertures may be provided in the common baffle or wall to permit water to flow therethrough into the filter chamber. The filter chamber may have an outlet for water from the filter chamber. The filter chamber may include a filtering media to filter solids from water flowing into the filter chamber and prevent or minimize solid flow through the outlet. A baffle may be provided in the filter chamber. The baffle may be hinged at its lower edge to the floor of the filter chamber. The baffle may be apertured to permit flow of water therethrough.

The biological filtering media of the respective biological treatment chambers may contain any type or types of bacteria or combinations of bacteria. Some of the bacteria may act to convert ammonia into nitrates and convert nitrites into nitrates. Other bacteria may be provided for removing phosphates from the water. Different bacteria or combinations of bacteria are selected depending upon the nature of contaminants in the water. Whilst the building is designed for use on land, it may also be adapted for floating on a body of water or liquid to be treated. For this purpose, the building may be provided with one or more buoyant bodies. The buoyant body or bodies may comprise a collar like body which extends around the building. The buoyant body or bodies may comprise foam plastics material or any other buoyant material or alternatively may comprise one or more air chambers.

Brief Description of the Drawings

In order that the invention may be more readily understood and put into practical effect reference will now be may to the company drawings which illustrate the preferred embodiments of the invention and wherein: Figs. 1 and 2 illustrate in opposite isometric views water treatment apparatus according to a first embodiment of the invention;

Figs. 3 and 4 are a further opposite isometric view of the apparatus of Figs. 1 and 2 with the roof or covers removed;

Fig. 5 is a further isometric view of the apparatus of Figs. 1 and 2 with the roof or covers and roof frame removed;

Fig. 6 is an isometric view of the apparatus of Figs. 1 and 2 with the roof or covers and side panels removed;

Fig. 7 is a plan view of the apparatus of Fig. 1 with the roof or covers removed; Fig. 8 is an end view of the apparatus of Fig. 1 with the roof or covers removed;

Fig. 9 is a longitudinal sectional view of the apparatus of Fig. 1 with the roof or covers removed;

Figs. 10 is an isometric view of a further- embodiment of water treatment apparatus according to the invention similar to the view of Fig. 3;

Fig. 11 is a plan view of the apparatus of Fig. 10;

Figs. 12 and 13 are opposite isometric views of a further embodiment of water treatment apparatus according to the invention; and

Fig. 14 illustrates water treatment apparatus according to the invention designed for floating on a body of water.

Detailed Description of the Preferred Embodiments

Referring to the drawings and firstly to Figs. 1 to 9, there is illustrated water treatment apparatus 10 according to an embodiment of the invention for treating water in a body of contaminated water. The apparatus 10 is in the form of a building 11 typically a portable building having a base 12 which is in the form of a tank of a rectangular configuration, the base 12 having a base frame 13 and infill panels or cladding 14 which define side walls 15, end walls 16 and a bottom or base wall 17 of the base 12 and building 11. A roof frame 18 is supported on the base 12 and comprises a plurality of curved roof frame members 19 extending between opposite side walls 15 of the base 12 and longitudinal roof frame members 20. A plurality of curved roof panels 21 are supported on the roof frame 18 of the building 11 to extend between and be supported by respective roof frame members 19 and 20. Some or all of the curved panels 21 are either hinged to the roof frame 18 or are removable from the roof frame 18 to provide access to the interior of the building 11. At one end of the building 11, a curved roof panel 21 is ■ replaced by an outwardly extending part rectangular roof end portion 22 to accommodate a drum filter 23 (see Fig. 3) described further below. The curved roof panels 21 may be locked in their position of Fig. 1 so that the building 11 may be left in a secure state adjacent a body of water to be treated.

The base 12 is divided centrally by a first longitudinally extending central baffle or wall 24. A series of substantially parallel transversely extending baffles or walls extend between the central baffle or wall 24 and one side wall 15 of the base 12. The baffles comprise a first transversely extending baffle or wall 25 which extends between the side wall 15 and central baffle or wall 24 but terminates above the base wall 17, the wall 25 defining a first chamber 26 at one end of the building 10.

The drum filter 23 is of similar configuration to the drum filters disclosed in our International Patent Application Nos. PCT/AU02/01245 and PCT/AU05/00878 and comprises a drum 27 which includes annular end members 28 supported externally on rollers 29. The drum 27 includes a plurality of circumferentially spaced open troughs 30 extending between the annular end members 24. A screen or mesh material 31 is provided over the troughs 30 between the end members 28 and extends. In an alternative arrangement, the drum 27 may include a plurality of circumferentially spaced ribs or members in place of the troughs 30 extending between the end members 28 with the screen material 31 extending circumferentially around the . ribs and thus round the periphery of the drum 27.

Water is supplied to the drum 27 via an inlet duct 32 which passes out through an end of the building 11 adjacent the roof section 22 and which extends longitudinally into the interior of the drum 27 and in an axial direction. A pump (not shown) is connectable to the inlet duct 32 to supply water to the drum 27. The duct 32 has spaced outlets 33 through which water may flow from the duct 32 to cooperate with the walls of the troughs 30 within the drum 27 (or with the ribs where used) to effect rotation of the drum 27.

A hopper-like channel 34 for catching debris from the drum screen material 30 is located above the inlet duct 32 and also extends in an axial direction into the drum 27. A spray bar or bars 35 is provided above the drum 27 for spraying water and/or applying a blast of air to the screen material 30 of the drum 27 to displace materials which are

^' caught by the channel 34. The spray bar 35 is connected to a pump and a clean supply of water and/or to an air compressor or air pump. The channel 34 has a waste outlet 36 at one end for direction of waste to a waste chamber (described below) on the side of the wall or baffle 24 opposite the chamber 26.

The drum filter 27 is supported above the chamber 26 which collects water filtered through the drum filter 27. The chamber 26 is provided with a bottom panel 37 which is parallel to and raised above the base wall 17. The panel 37 is perforated or provided with openings to as to be in the form of a grille. The chamber 26 in use contains a biological filter media 38 (shown schematically in Fig. 9) which is supported on the panel 37 for supporting bacteria for biological treatment of water in the chamber 26. The media may be in any form but preferably comprises a plurality of discrete elements such as short sections of plastics hose or tube for carrying bacteria.

The chamber 26 also includes an agitator 39 in the form of a vertically axled rotor

40 which is coupled to a drive motor 41 such as an hydraulic motor or electric motor which when actuated effects rotation of the rotor 40. The drive motor 41 may be connected to a timer so as to cause operation of the drive motor 41 at regular intervals so as to agitate the biological media 38.

A second baffle 42 parallel to the baffle 25 is spaced from the baffle and extends upwardly from the base 17 but terminates below the upper edge of the baffle 25. The baffle 42 defines with the baffle 25 a second chamber 43 adjacent the chamber 26. One or more ultraviolet lamps (shown in dotted outline) may be supported in the chamber 43 such that water in the chamber 43 is exposed to ultraviolet light. The upper edge 44 of the baffle 42 defines a weir over which water may flow as described below and as shown by the flow arrows in Fig. 9.

A series of further baffles 45, 46, 47, 48 and 49 extend between the central baffle 23 and side wall 15 to define further a series of further water treatment chambers 50, 51, 52, 53 and 54 between respective baffles. The baffles 45, 47 and 49 are similar to the baffle 44 in that they terminate above the bottom wall 17 of the base 12 so that a flow passage is defined between the lower edge of each baffle 45, 47 and 49 and bottom wall 17 with the upper edges of the respective baffles 45, 47, 49 and 25 being substantially at the same level.

The chamber 50 includes means for introducing ozone into the water in the chamber 50 comprising one or more ozone outlets 55 for example air stones at a lower portion of the chamber 50 and connected to a source of ozone. The chamber 52 is also provided with similar ozone outlets 56. The chambers 51 and 53 may include one or more ultraviolet lamps (as in the chamber 44) such that water flowing through those chambers is subject to ultraviolet light. Alternatively the chambers 51 and 53 may be free of the ultraviolet light sources. The final chamber 54 also includes one or more ultraviolet lamps 57.

The baffle 49 defines with the opposite end wall 16 a second biological filter chamber 58. The chamber 58 has a base panel 59 which is perforated or provided with a plurality of openings so as to be of a grille-like form and therefore similar to the base panel 36. Further biological media 60 is supported on the panel 59 for carrying further bacteria for bacteriological treatment of water in the chamber 58. A further agitator 61 similar to the agitator 39 and comprising a vertically axled rotor 62 is also provided in the chamber 58, the rotor 62 being coupled to a motor 63 which when actuated will drive the rotor 62 to agitate the bacteriological media 60.

An outlet 64 which is in the form, of a duct extends from the upper end of the chamber 58 through the panel 24, the outlet 64 being located adjacent the side wall 16 of the building 11. A right-angle section of mesh grid 65 extends across the full width of the chamber 58 to separate the chamber 58 from the outlet 64. The outlet 64 is connected to a pair of spaced perforated distribution pipes 66 which are arranged on the opposite side of the baffle 24 and extend parallel thereto, the pipes 66 being supported at an elevated attitude by spaced transversely extending frame members 67. The pipes 66 may be partially open on their upper side to allow inspection.

A transverse baffle 68 extends between the central baffle 24 and opposite side wall 15 of the base 12 to define a further biological treatment chamber 69. A base panel 70 of grille-like form and similar to the panels 37 and 39 is supported above the base wall 17. The base wall 17 supports further biological media for carrying bacteria for treating of water in the chamber 69: Treated water outlets 71 are provided beneath the panel 70 and extend outwardly through the adjacent side wall 15 of the base 12.

A further baffle 72 extending between the baffle 24 and wall 15 defines with the baffle 68 a waste chamber 73 having an outlet 74 which extends through the side wall 15. The outlet 36 from the waste collection trough 34 from the drum filter 23 is connected via ducts 75 to the waste chamber 73.

The baffle 72 defines with the adjacent end wall 16 of the base 12, a housing 76 for carrying various components for operating the apparatus 10. In this case the housing 76 houses a series of ozone generators 77, a hydraulic pump and reservoir 78 for supplying hydraulic fluid to the agitator motors, and a control box and power supply 79. Access is provided to the housing 76 via a door 80. The housing 76 may also house a pump for pumping in water through the inlet 32 and electrical supply devices for supplying current to the ultraviolet lamps. The housing 76 may also house an air pump or pumps for supply air to chamber or chambers where required for bubbling through water in the chamber or chambers.

In use, water to be treated is supplied to the inlet 32 by means of a pump or under the influence of gravity to pass initially into the drum filter 28. This causes rotation of the drum 27 with water passing through the screen material 30 into the chamber 26 to be subject to biological treatment. Where the screen 30 is to be cleaned, water or air is supplied to the spray bar 35 to spray the screen material 30 as the drum 27 rotates with waste materials displaced from the screen material 30 collecting in the channel 34 where it is directed through the outlet 36 and ducting 75 to the waste chamber 73 to pass out through the outlet 74 to waste.

Water treated in the biological treatment chamber 26 passes downwardly through the grille panel 37 and flows upwardly through the chamber 43 where it is exposed to ultraviolet light from the UV lamps (if used). The water then flows over the upper edge 44 of the baffle 42 and downwardly through the. chamber 50 to be subject to ozone from the outlets 55 which bubbles upwardly through the downwardly flowing water. Water continues flowing in a serpentine manner under the influence of gravity and as indicated by the arrows in Fig. 9 beneath the lower edge of the baffle 45, up the chamber 51., over the upper edge of the baffle 46, downwardly through the chamber 42 to be again subject to ozone treatment from ozone bubbling upwardly from the outlets 56. Water then flows under the lower edge of the baffle 47 and upwardly over the upper edge of the baffle 48 to flow downwardly through the chamber 54 to be exposed to ultraviolet light. Water then flows beneath the baffle 49 upwardly through the grille-like panel 59 into the chamber 58 to be subject again to biological treatment in the chamber 58. When the water rises to a sufficient level in the chamber 58, it will reach the outlet 64 through which it will flow into the distribution pipes 66. The mesh 65 prevents any solids flowing through the outlet 64 into the pipes 66.

Water is distributed by the pipes 66 over the biological filter media supported on the grill panel 70 and trickles downwardly through the media to be subject to bacteriological treatment from bacteria carried by the media before flowing through the outlets 71.

At regular intervals, the agitator rotors 40 and 62 are rotated by the motors 41 and 63 to agitate the biological filter media and increase the biological filtration action.

Figs. 10 and 11 illustrate an alternative water treatment apparatus 80 in the form of a building according to a further embodiment of the invention which is similar externally to the embodiment of Figs. 1 to 9 and which components similar to the embodiment of Figs. 1 to 9 have been given the same numerals. As above the base 12 is formed into a series of chambers by a first longitudinally extending central baffle or wall 24 and transversely extending baffles or walls on the opposite sides of the central baffle or wall 24. A first transversely extending baffle or wall 82 extends between the side wall 15 towards the central baffle or wall 24 but terminates short of the baffle or wall 24, the wall 21 defining a first chamber 83 at_. one end of the apparatus 80. The drum 27 of the drum filter 23 which in this case is oriented transversely of the building is supported over the chamber 83 which collects water filtered through the drum filter 27. The chamber 83 carries biological filter media carrying bacteria for biological treatment of water in the chamber 83.

The space between the free end of the wall or baffle 82 and central wall 24 defines an inlet 84 for water to flow from the chamber 82 into a second chamber 85 defined between the wall or baffle 82 and a further wall or baffle 86 extending parallel to the wall or baffle 82 from the central wall 24. The wall or baffle 86 terminates short of the side wall 15 of the base 12 to define an outlet 87 such that water may flow around the free end of the wall or baffle 86.

The chamber 85 includes one or more ultraviolet light sources in the form of lamps 88 so that water in the chamber 85 is exposed to ultraviolet light in its passage from the inlet 84 to the outlet 87.

A further baffle or wall 89 extends from the outer wall 15 of the base 12 towards the central wall or baffle 24 and terminates short thereof and defines therewith an outlet 90 at the end of the wall or baffle 89. The wall 89 defines with the wall 86 a further chamber 91. Water flowing into the chamber 91 from the outlet 87 from the chamber 85 is exposed to ozone. For this purpose means are provided for introducing ozone into the water in the chamber 91. Such means include one or more ozone outlets for example air stones 92 at a lower portion of the chamber 91 and connected to a source of ozone which bubbles upwardly through the water flowing into the chamber 91 for sterilizing the water. Alternatively or additionally air may also be introduced into the chamber 91 to bubble through the water therein so that the chamber 91 acts as a foam fractionator to remove impurities in the water.

Water from the outlet 90 flows into a second biological filter chamber 93 which extends from the baffle or wall 87 around the end of the central wall or baffle 24 to a baffle or wall 94 on the opposite side of the base 12 and extending between the central wall 24 and opposite side wall 15 of the base 12. The biological filter chamber 93 contains a biological filter media containing bacteria to subject water in the chamber 93 to biological filtration treatment. Outlets 95 in the side wall 15 of the base 12 adjacent the wall or baffle 94 provide an outlet for treated water for example for return of water to the body of water being treated.

A waste chamber 96 (equivalent to the waste chamber 73 of Fig. 5) is defined between the baffle 94 and a further transverse baffle or wall 97 to collect wastes flushed from the drum 27. The further baffle or wall 97 is provided with a series of openings 98 through which water from the waste chamber 96 may flow into a filtration chamber 99. Solids however are substantially prevented from passing into the chamber 99. An outlet 100 communicates with the chamber 99 to direct filtered water if required back into the body of water being treated. The filtration chamber 99 is provided with a filtration media such as a screen or foam which acts as a physical filter to trap sediment and solids in the .chamber 99 to prevent them from passing through, the outlet 100. A panel 101 is also provided in the filtration chamber 99, the panel 101 being pivotally connected at its lower edge to the base for pivotal movement about a horizontal hinge axis. The panel 101 has apertures in it to permit water flow therethrough but to block solids. The panel 101 may be pivoted about its hinge axis to permit placement of the filter media into or removal of the filtration media from the chamber 99 between the baffle 97 and panel 101.

As in the embodiment of Figs. 1 to 9, water flows in a serpentine manner through the chambers 85 and 91 for treatment by being subject to ozone and ultraviolet light. Water is additionally subject to biological treatment initially in the chamber 83 and then in the chamber 93.

Figs. 12 and 13 illustrate yet a further embodiment of water treatment apparatus 102 in the form of a building which is similar to the embodiment of Figs. 10 and 11 and in which like components have been given like numerals. In this case however the chambers 85 and 91 are replaced by a single chamber 103 which can contain an ultraviolet light source or sources, ozone outlets through which ozone can pass for bubbling through water in the chamber 103 and/or air outlets through which air can pass for bubbling through water in the chamber 103.

The chamber 103 is defined between spaced walls or baffles 104 and 105, the lower edge of the wall 104 being elevated above the base of the tank to permit water to flow beneath the wall 104 from the chamber 83 into the chamber 103. Water exits the chamber 103 into the chamber 83 either over the upper edge of the wall 103 or through apertures in the wall 103 (shown in dotted outline). Of course other arrangements may be provided for conveying water to the chamber 103 from the biological treatment chamber 83 and from the chamber 103 into the chamber 93 for biological treatment.

Whilst the apparatus described above is typically in the form of a land based building which is positioned adjacent to a body of water to be treated which is connected to the inlet, the apparatus may be arranged to float on a body of water. For this purpose, a flotation collar 105 as shown in Fig. 14 is provided around and secured to the building 11 which may be in any of the forms described above. Alternatively, the building 11 may releasably seat on the collar 105. The flotation collar 105 may be formed of a buoyant material or may comprise one or more hollow chambers for containing air. The flotation collar 105 may be in other forms that that illustrated and for example may be replaced by separate spaced floats. In use the water treatment apparatus described above is arranged to float in a body of water to be treated and may be self-powered to move around the body of water or moved by other means around the body of liquid. Alternatively the apparatus may be anchored or moored in a fixed position. Water will be continuously treated by the apparatus being pumped in through the inlet 32 with treated water flowing back to the body of water through the outlets 71. The floating building 11 may include a power source for supplying power to the ultraviolet lamps and/or ozone generators. The power source may incorporate a solar panel or solar cells.

Whilst particular combination of screens filter, biological treatment chambers, ultraviolet treatment chambers, foam fractionator chambers and/όr ozone treatment chambers have been described, different combinations of filtering or water treatment components may be employed and additional components added in series or parallel if required. The filtering or treatment components may also be arranged in a different sequence. The biological media in the biological treatment chambers may carry aerobic or anaerobic bacteria. For example, the chambers 26 and 69 may carry aerobic bacteria and the chamber 58 may carry anaerobic bacteria. Typically one biological treatment chamber may bacteria for removing ammonia and nitrites from the water and another biological treatment chamber may include biological filter media for removing phosphates from the water. In some cases however the biological treatment chambers may carry more than one type of bacteria so that for example ammonia and phosphates can be removed in one chamber. The media supported in each biological treatment- chamber may be of any form but typically comprises a plurality of elements such as short sections of plastic pipe. The baffles or walls which define the respective chambers typically are in the form of planar panels but may be of other configurations. The baffles, or walls may be formed of metal, plastics or any other material. Similarly the outer cladding of the base 12 may be of plastics, metal or any other water impervious material. As referred to above some of the roof panels 21 may be hinged to the frame 18 to allow access to the interior of the building 11. Thus the side roof panels 21 adjacent the roof end portion 22 may be hinged to the adjacent roof frame member 20 for movement upwardly about a horizontal axis to allow access to the interior of the building for inspection or any other purposes. The opposite roof panels 21 are also preferably hinged in a similar manner. The roof end portion 22 may also be removable to allow access to the drum filter 23.

Whilst the building comprising the water treatment apparatus is shown in the embodiments to be of a particular shape and configuration it may be of many different shapes other than that described. The roof of the building may also be other than the curved "igloo" like configuration illustrated.

It should be noted that reference to the prior art herein. is not to be taken as an acknowledgement that such prior art constitutes common general knowledge in the art.

The terms "comprising" or "comprise" or derivatives thereof as used throughout the specification and claims are taken to specify the presence of the stated features, integers and components referred to but not preclude the presence or addition of one or more other feature/s, integer/s, component/s or group thereof.

Whilst the above has been given by way of illustrative embodiment of the invention, all such variations and modifications thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as defined in the appended claims.

Claims

1. Water treatment apparatus comprising a building having a tank-like base for containing water, water treatment means within said building, a water inlet to said water treatment means, said water treatment means including a series of water-treatment chambers defined within said base and in which water can undergo different water treatments, and a water outlet for water treated by the water treatment means.

2. Water treatment apparatus as claimed in claim 1 wherein baffles or walls are provided in the base to divide the base into said series of chambers and wherein said chambers are arranged such that water flows in a serpentine manner through at least some of the chambers from one chamber to the next chamber.

3. Water treatment apparatus as claimed in claim 2 wherein said base is of a rectangular configuration and a dividing baffle or wall is provided in the base to extend centrally thereof and wherein said series of chamber are provided at least on one side of the dividing baffle or wall.

4. Water treatment apparatus as claimed in claim 3 wherein said chambers are defined by further baffle or walls extending transversely of the dividing baffle or wall.

5. Apparatus as claimed in any one of claims 2 to 4 wherein said water treatment means comprises one or more of a screen filter, means for exposing water to be treated to ozone, means for exposing water to be treated to ultraviolet light, means for exposing the water to bubbles of gas or air to separate impurities from the water and a biological filter.

6. Apparatus as claimed in claim 5 and including a screen or drum filter adapted to receive water from said inlet, said screen or drum filter being supported over a first chamber of said series of chambers for collecting water filtered by said screen or drum filter, said first chamber comprising a biological filter chamber for containing biological filter media for supporting bacteria for biological treatment of water filtered by the screen or drum filter.

7. Apparatus as claimed in claim 6 wherein said first chamber includes a raised bottom wall for supporting the biological filter media, said raised bottom wall being pervious to water.

8. Apparatus as claimed in claim 6 or claim 7 and including agitating means for selectively agitating said biological filter media.

9. Apparatus as claimed in claim 8 wherein said agitating means includes a rotor and means for selectively rotating said rotor.

10. Apparatus as claimed in any one of claims 6 to 9 and including a plurality of further transverse baffles or walls extending substantially parallel to said first baffle or wall and defining therebetween respective said chambers of the series of chambers.

11. Apparatus as claimed in claim 10 wherein a baffle or wall is arranged such that water may flow around or through one end thereof from one chamber to the next chamber.

12. Apparatus as claimed in claim 11 wherein said baffle or wall is spaced at one end from a side wall of the base or dividing baffle or wall.

13. Apparatus as claimed in claim 10 wherein at least one baffle or wall is arranged such that water may flow under or through a lower portion of the baffle or wall from one chamber to the next chamber.

14. Apparatus as claimed in claim 13 wherein the lower edge bottom of the baffle or wall is spaced above a floor of the base.

15. Apparatus as claimed in claim 10 wherein the upper edge of at least one baffle or wall defines a weir over which water may from one chamber to the next chamber.

16. Apparatus as claimed in claim 8 wherein at least one baffle or wall has apertures in an upper end thereof to permit water to flow from one chamber to the next chamber.

17. Apparatus as claimed in any one of claims 11 to 16 wherein said baffles or walls defining respective chambers are arranged such that water flows around or through opposite ends of respective said baffles.

18. Apparatus as claimed in any one of claims 6 to 17 wherein at least one of said chambers includes water treatment means comprising ^• one or more ultraviolet light sources such that water in said chamber can be exposed to ultraviolet light.

19. Apparatus as claimed in any one of claims 6 to 17 wherein at least one of said chambers include water treatment means comprising means to expose water in said at least one chamber to ozone.

20. Apparatus as claimed in claim 19 and including one or more ozone outlets at a lower end of said at least one chamber.

21. Apparatus as claimed in any one of claims 6 to 17 wherein at least one of said chambers includes water treatment means comprising means for supplying air to a lower portion of said at least one chamber for bubbling through water therein.

22. Apparatus as claimed in claim 21 and including one or more air blocks or outlets in a lower portion of said at least one chamber for supplying said air.

23. Apparatus as claimed in any one of claims 6 to 22 wherein a said chamber comprises a second biological treatment chamber containing media adapted to support bacteria for treatment of water in said chamber.

24. Apparatus as claimed in claim 23 wherein said biological treatment chamber includes a raised base, said base being pervious to water to permit water to flow into said chamber.

25. Apparatus as claimed in claim 24 and including an outlet at the upper end of said further chamber.

26. _. Apparatus as claimed in claim 25 and including a screen or mesh material separating said outlet from said biological media within said chamber.

27. Apparatus as claimed in claim 25 or claim 26 and including a third biological filter chamber and wherein- said outlet communicates with elongated distribution means for distributing water from said outlet over said chamber.

28. Apparatus as claimed in claim 26 wherein said outlet includes a floor pervious to water and wherein said water outlet from said apparatus is provided beneath said pervious floor.

29. Water treatment apparatus as claimed in any one of the preceding claims and including one or more buoyant bodies for supporting said building on a body of water.