WO2008092188A1

WO2008092188A1 - Wastewater treatment system

Info

Publication number: WO2008092188A1
Application number: PCT/AU2008/000035
Authority: WO
Inventors: Guido Stangherlin; Stan Westcott
Original assignee: Easternwell Group Holdings Pty Ltd
Priority date: 2007-01-31
Filing date: 2008-01-14
Publication date: 2008-08-07
Also published as: AU2008210255B2; AU2008210255A1

Abstract

A portable wastewater treatment system (1) comprising: a homogenisation chamber (2) having an inlet (20) attachable to a wastewater source and containing a homogeniser (21) for homogenising solid constituents of the wastewater; a primary separation chamber (3) for separating constituents of the wastewater and having an inlet (36) extending to the homogenisation chamber (2); an aeration chamber (4-6) for promoting the consumption of organic constituents of the wastewater by aerobic microbes and having an inlet (45) extending to the primary separation chamber (3); an aerator (13) for introducing air into the aeration chamber (4-6); a secondary separation chamber (7) for further separating constituents of the wastewater and having an inlet (72) extending to the aeration chamber (4-6); a disinfection chamber (8) for disinfecting the wastewater, said disinfection chamber (8) having an inlet (81) extending to the secondary separation chamber (7); a wastewater collection chamber (9) having an inlet (91) extending to the disinfection chamber (8) and having a discharge pump (93) for discharging wastewater to the natural environment by way of a filtration chamber (10), a UV treatment chamber (11) and a sprinkler (12); and containment valves (20, 38, 75, 102) associated with one or more of the inlets and/or the outlet, for containing the wastewater within one or more of the chambers (2-9) when moving the system (1) from one location to another.

Description

Title

WASTEWATER TREATMENT SYSTEM Field of the Invention

This invention relates to a wastewater treatment system. In particular, the invention concerns a portable wastewater treatment system that is particularly suited for treating sewage and for discharging treated sewage to the environment.

Background of the Invention

Many different types of wastewater treatment systems are known. However, very few are portable. A problem with those systems that are portable is that they must be emptied of their wastewater content prior to being transported, and this makes use of such systems inconvenient and time consuming.

Detailed Description of the Invention

It is an object of the present invention to provide a portable wastewater treatment system which overcomes the problem referred to above, or to provide the public with a useful or commercial choice.

According to the present invention, there is provided a portable wastewater treatment system comprising:

a homogenisation chamber having an inlet attachable to a wastewater source and containing a homogeniser for homogenising solid constituents of the wastewater;

a primary separation chamber for separating constituents of the wastewater and having an inlet extending to the homogenisation chamber;

an aeration chamber for promoting the consumption of organic constituents of the wastewater by aerobic microbes and having an inlet extending to the primary separation chamber;

an aerator for introducing air into the aeration chamber;

a secondary separation chamber for further separating constituents of the wastewater and having an inlet extending to the aeration chamber; a disinfection chamber for disinfecting the wastewater, said disinfection chamber having an inlet extending to the secondary separation chamber and an outlet for disinfected wastewater; and

containment valves associated with one or more of the inlets and/or the outlet, for containing the wastewater within one or more of the chambers when moving the system from one location to another.

The homogenisation chamber may be of any suitable shape and volume. Preferably, the chamber has a volume of about 400-1000 L. The chamber may have an upper region and a lower region. Any suitable type of inlet may be used. An end of the inlet may be attachable to any suitable type wastewater source in any suitable way, e.g. by way of a quick coupling or a threaded coupling. Preferably, the wastewater source is a sewage system (servicing a toilet, shower or bath) and the inlet is attachable to a conduit of that system. The homogenisation chamber may have more than one inlet for wastewater.

Any suitable type of homogeniser may be used. Preferably, the homogeniser is a pulverising or grinding pump located within the homogenisation chamber. The pump may be manually activated or automatically activated, say, by way of a float switch. The pump may be driven electrically, pneumatically or hydraulically. The homogenisation chamber may contain more than one pulverising or grinding pump.

The primary separation chamber may be of any suitable shape and volume.

Preferably, the chamber has a volume of about 800-4000 L. The primary separation chamber may have an upper region and a lower region. Preferably, the primary separation chamber enables constituents of the wastewater that are more buoyant than water to accumulate at the water's surface and constituents that are less buoyant than water to accumulate at the lower region of the chamber.

The primary separation chamber may have a drain located at the upper region of the chamber through which grease, plastic constituents and other lighter than water constituents may be removed. The drain (grease trap) may be of any suitable construction. The primary separation chamber may have a drain located at the lower region of the chamber through which sludge and other settled constituents may be removed. The drain may be of any suitable construction.

The primary separation chamber inlet may be of any suitable construction. Preferably, one end of the inlet extends from one or more pulverising or grinding pumps and the other end of the inlet is situated between the upper and lower regions of the primary separation chamber.

Preferably, the primary separation chamber inlet has backflow-prevention means for preventing wastewater from backflowing to the homogenisation chamber. Any suitable backflow-prevention means may be used. For instance, the inlet may have an upper region having an air intake port, so as to prevent siphoning of wastewater from the primary separation chamber to the homogenisation chamber. Alternatively, or additionally, the backflow-prevention means may comprise a backflow control valve that automatically prevents the backflow of wastewater to the homogenisation chamber.

The aeration chamber may be of any suitable shape and volume. Preferably, the aeration chamber has a volume of about 2500-4500 L. The aeration chamber may have an upper region and a lower region. The aeration chamber may comprise primary, secondary and tertiary aeration sub-chambers that are separated by upstanding walls or baffles and the sub-chambers may be in fluidic communication with one another.

The aeration chamber may have a drain located at the upper region of the chamber and a drain located at the lower region of the chamber. The drains may be of any suitable construction.

Any suitable type of aerator may be used for introducing air into the aeration chamber. Preferably, the aerator comprises an air pump and a manifold extending from the pump to the lower region of the aeration chamber. Openings in the manifold may allow bubbles of air to escape from the manifold into the aeration chamber when the pump is in operation.

The growth of aerobic microbes in the aeration chamber may be promoted in any suitable way. For instance, the growth of aerobic microbes may be promoted by way of a fixed film system or a suspended growth system. Preferably, the aeration chamber contains a medium, a filter or a scaffold that aerobic microbes may colonise and grow. Any suitable type of medium, filter or scaffold may be used. For instance, porous geotextile fibre mats, textiles or ceramic tubes may occupy a large volume of the aeration chamber and may be situated above the openings for air in the manifold.

The aeration chamber inlet may be of any suitable construction. The aeration chamber inlet may have backflow-prevention means for preventing wastewater from backflowing to the primary separation chamber. Any suitable backflow-prevention means may be used. For instance, the inlet may have an upper region having an air intake port, so as to prevent siphoning of wastewater from the aeration chamber to the primary separation chamber. Alternatively, or additionally, the backflow-prevention means may comprise a backfiow control valve that automatically prevents the backflow of wastewater to the primary separation chamber.

The secondary separation chamber may be of any suitable size and volume. Preferably, the secondary separation chamber has a volume between about 200-500 L. The secondary separation chamber may have an upper region and a lower region. The shape of the secondary separation chamber may encourage the settling of constituents that are heavier than water (e.g. sludge) at a lower region of the chamber. For instance, the chamber may have a sloping sidewall such that sludge settles in a lower corner of the chamber.

The secondary separation chamber may have a drain located at the upper region of the chamber and a drain located at the lower region of the chamber for removing settled constituents. The drains may be of any suitable construction.

The secondary separation chamber inlet may be of any suitable construction. The secondary separation chamber inlet may have backflow-prevention means for preventing wastewater from backflowing to the aeration chamber. Any suitable backflow-prevention means may be used. For instance, the inlet may have an upper region having an air intake port, so as to prevent siphoning of wastewater from the secondary separation chamber to the aeration chamber. Alternatively, or additionally, the backflow-prevention means may comprise a backflow control valve that automatically prevents the backflow of wastewater to the aeration chamber.

The secondary separation chamber may comprise a return pump for returning settled constituents from the lower region of the secondary separation chamber to the primary separation chamber. Any suitable type of pump may be used. The pump may be manually activated or automatically activated, say, by way of a sensor or timer. The pump may be driven electrically, pneumatically or hydraulically. Preferably, the pump has a return line extending to the upper region of the primary separation chamber. The return line may have backflow-prevention means as described above. The secondary separation chamber may contain more than one return pump.

The disinfection chamber may be of any suitable shape and volume. Preferably, the disinfection chamber has a volume between about 400-800 L. The disinfection chamber may have an upper region and a lower region.

The disinfection chamber may have a drain located at the upper region of the chamber and a drain located at the lower region of the chamber. The drains may be of any suitable construction.

The disinfection chamber inlet may be of any suitable construction. The disinfection chamber inlet may have backflow-prevention means for preventing wastewater from backflowing to the secondary separation chamber. Any suitable backflow-prevention means may be used. For instance, the inlet may have an upper region having an air intake port, so as to prevent siphoning of wastewater from the disinfection chamber to the secondary separation chamber. Alternatively, or additionally, the backflow-prevention means may comprise a backflow control valve that automatically prevents the backflow of wastewater to the secondary separation chamber.

The disinfection chamber may have any suitable disinfector for disinfecting the wastewater. The disinfector may be, for example, of a chemical nature, such as chlorine or silver. Alternatively, the disinfector may be a source of ultraviolet light. Alternatively, the disinfector may be ozone. Such disinfectors are well known in the art. If the disinfector is of a chemical nature, the disinfection chamber inlet may have a disinfector intake so that chemicals, such as chlorine or silver tablets, may be introduced into the chamber. The disinfection chamber inlet may have a lower end adapted to contain such tablets and to leach chemicals into the chamber.

The aerator may further introduce air into the disinfection chamber so as to promote the mixing of the wastewater with the disinfector. To this end, the manifold of the aerator may also extend to the lower region of the disinfection chamber.

The outlet of the disinfection chamber may be of any suitable construction. An end of the outlet may be attachable to, say a sprinkler system, or may convey disinfected wastewater to yet other chambers for further treatment (e.g. polishing).

The disinfection chamber outlet may have backflow-prevention means for preventing wastewater from backflowing to the disinfection chamber. Any suitable backflow-prevention means may be used.

The wastewater treatment system may further comprise a wastewater collection chamber from which the disinfected wastewater may be pumped or otherwise removed.

The wastewater collection chamber may be of any suitable shape and volume. Preferably, the wastewater collection chamber has a volume between about 50-300 L. The wastewater collection chamber may have an upper region and a lower region.

The wastewater collection chamber may have a drain located at the upper region of the chamber and a drain located at the lower region of the chamber. The drains may be of any suitable construction.

The wastewater collection chamber may have a discharge pump for pumping disinfected wastewater to a sprinkler system or to yet other chambers for further treatment. Any suitable type of discharge pump may be used. The discharge pump may be manually activated or automatically activated, say, by way of a sensor (e.g. float switch). The discharge pump may be driven electrically, pneumatically or hydraulically. Preferably, the discharge pump has an outlet extending from the wastewater collection chamber. The outlet may have backflow-prevention means as described above. The wastewater collection chamber may have more than one discharge pump. The wastewater treatment system may comprise further chambers having passive or active filters as well as additional disinfectors, for polishing the wastewater prior to discharge.

As previously mentioned, the containment valves may be associated with one or more of the inlets and/or the outlet, and contain the wastewater within one or more of the chambers when moving the system from one location to another. The containment valves may be of any suitable construction. The containment valves may be automatically or manually moved between open and closed positions, wherein in the open position wastewater can flow there through and in the closed position wastewater cannot flow there through. In some cases, the backflow-prevention means can serve as containment valves. Preferably, containment valves are associated with at least the homogenisation chamber inlet, the primary separation chamber inlet, the secondary separation chamber inlet, and the disinfection chamber outlet or the wastewater collection chamber outlet.

The containment valves may be closed such that wastewater is contained within the primary and secondary separation chambers, the aeration chamber and the disinfection chamber, such that the system may be moved from one location to another without the spillage of wastewater. Preferably, the containment valves are hand-operated taps.

The wastewater treatment system may have at least one housing which provides the homogenisation, primary and secondary separation, aeration and disinfection chambers. The housing may be of any suitable size, shape and construction. Preferably, the housing comprises a base wall, a top wall, side walls and internal walls. The housing may be made of any suitable material or materials, but is preferably made of metal.

The wastewater treatment system may include a step ladder so as to allow access to the top wall of the housing. The wastewater treatment system may include hand rails extending along a periphery of the top wall. The top wall may include service hatches, enabling access to one or more of the chambers.

The wastewater treatment system may be portable in any suitable way. The system may include pockets for tines of a forklift or lifting fixtures for lifting with a crane. The wastewater treatment system may include a transport skid. The system may be mounted or mountable to a trailer. The system may be integrated in sanitary amenities, particularly portable sanitary amenities.

The wastewater treatment system may further comprise a strainer to remove large objects prior to the wastewater entering the homogenisation chamber. Such objects requiring removal may be condoms, sanitary towels, tampons or litter.

The wastewater system may include a sprinkler system through which treated wastewater may be discharged to the environment. Any suitable type of sprinkler system may be used.

The wastewater treatment system may include a control panel for controlling the pumps and containment valves (if solenoid driven, for example) and other constituents of the system. The pumps of the system may be either in-line pumps or submersible pumps.

Such pumps may be activated by timers, flow switches or using other types of sensors.

Such pumps may operate continuously.

Preferred embodiments of the invention will now be described, by way of example, with reference to the accompanying figures.

Brief Description of the Figures

Figure 1 is a cross-sectional view of a wastewater treatment system according to an embodiment of the present invention;

Figure 2 is a cross-sectional view of a wastewater treatment system according to an embodiment of the present invention;

Figure 3 is a perspective view of a wastewater treatment system according to an embodiment of the present invention; and

Figure 4 is a detailed plan view of a wastewater treatment system incorporated into a transport container containing amenities.

Description of the Preferred Embodiments

In the figures, like reference numerals refer to like features. Referring first to figure 1, there is shown a wastewater treatment system 1 according to a first embodiment of the present invention. The system 1 comprises a homogenisation chamber 2, a primary separation chamber 3, an aeration chamber 4, 5, 6, a secondary separation chamber 7, a disinfection chamber 8, a collection chamber 9, a filtration chamber 10, a UV treatment chamber 11, a sprinkler 12, and an aerator 13.

The homogenisation chamber 2 is provided by a top wall 400, a bottom wall 401 and four side walls 402. The homogenisation chamber 2 has an upper region, a lower region and eight inlets 20 for wastewater. The chamber 2 has a volume of about 880 L and a working volume of about 525 L. A threaded end of the inlet 20 is attachable to a wastewater source, such as to a threaded end of an outlet pipe of a sewage system. Wastewater may either gravity flow to the chamber 2 or be pumped to the chamber 2.

The homogenisation chamber 2 has two electric grinder pumps 21 that are activated by way of float switches. The pumps 21 grind up solid wastes of the wastewater and convey homogenised wastewater (i.e. having suspended solid wastes) to the primary separation chamber 3.

The primary separation chamber 3 and aeration chamber 4, 5, 6 are provided by a top wall 410, a base wall 411, four side walls 412 and an internal wall 413 that separates those chambers 3, 4.

The primary separation chamber 3 has a volume of about 1260 L and a working volume of about 1023 L. The chamber 3 has an upper region and a lower region, and an inlet pipe 36. The chamber 3 enables grease, oil and plastics materials, as well as other constituents that are more buoyant than water, to accumulate at the water's surface at the upper region of the chamber 3. The chamber 3 enables faecal matter and other constituents of the wastewater that are less buoyant than water to accumulate at the lower region of the chamber 3.

A drainage pipe 31 having a tap 32 is located at the upper region of the chamber 3, and the tap 32 can be opened to drain grease 33 etc. from the chamber 3.

A drain 34, for removing settled constituents 35 of the wastewater (e.g. faecal matter), is located at the lower region of the chamber 3. The inlet pipe 36 extends from both grinding pumps 21 through the upper region of the chamber 2 and to a location between the upper and lower regions of the primary separation chamber 3. The inlet pipe 36 is forked and has an air intake port 37 so as to prevent siphoning of wastewater from the primary separation chamber 3 to the homogenisation chamber 2. Two containment taps 38 are associated with the inlet pipe 36 and can be moved between open and closed positions.

The aeration chamber 4, 5, 6 has an upper region, a lower region and an inlet pipe 45 for wastewater from the primary separation chamber 3. The chamber 4, 5, 6 has a total volume of about 3780 L and a working volume of about 3069 L. This volume can accommodate the wastes of about 20 people (i.e. about 150 L per person). The aeration chamber 4, 5, 6 comprises primary 4, secondary 5 and tertiary 6 aeration sub-chambers that are separated by internal baffle walls 41, 51, 61. Openings 52, 62 in the baffle walls 41, 51, 61 enable wastewater to flow from sub-chamber 4 to sub-chamber 6.

Although not illustrated, the aeration chamber 4, 5, 6 has a drainage pipe located at the lower region of the chamber 4, 5, 6.

The aerator 13 comprises an electrically driven air pump 131 and a pipe manifold 132 extending from the pump 131 to the lower region of each sub-chamber 4, 5, 6. Openings 133 in the pipe manifold 132 allow bubbles of air to leave the manifold 132 and to travel through the sub-chambers 4, 5, 6 when the pump 131 is in operation.

Although not illustrated, each sub-chamber 4, 5, 6 contains a bioactive filter made from coarse material (e.g. unwoven textiles or ceramic tubes, or any matter which will produce a large surface area and not become clogged easily) on which aerobic microbes may colonise and grow. The filter occupies a large part of each sub-chamber 4, 5, 6

An inlet pipe 45 extends from the primary separation chamber 3 to sub-chamber 4. The inlet pipe 45 is forked and has an air intake port 46 so as to prevent siphoning of wastewater from the sub-chamber 4 to the primary separation chamber 3.

The secondary separation chamber 7 is provided by a top wall 420, a sloping bottom wall 72 and side walls 421. The secondary separation chamber 7 has a volume of about 404 L and a working volume of about 238 L. The chamber 7 has an upper region and a lower region, and an inlet pipe 71. The sloping bottom wall 72 of the chamber 7 encourages the settling of constituents that are heavier than water 73 (e.g. sludge) at the lower corner of the chamber 7.

The inlet pipe 71 extends from sub-chamber 6 to the secondary separation chamber 7. The inlet pipe 71 is forked and has an air intake port 72 so as to prevent siphoning of wastewater from the secondary separation chamber 7 to the sub-chamber 6.

A containment tap 75 is associated with the inlet pipe 71 and can be moved between open and closed positions.

The secondary separation chamber 7 has an electrical sludge return pump 76 for returning settled constituents 73 (e.g. sludge) from the chamber 7 to the primary separation chamber 3. A timer periodically activates the pump 76. An intake line 78 of the pump 76 extends from the lower region of chamber 7 to the pump 76 and a return line

79 of the pump 76 extends from the pump 76 to the upper region of chamber 3.

The disinfection chamber 8 and wastewater collection chamber 9 are provided by a top wall 430, a bottom wall 431, four side walls 432 and an interior wall 433 that separates chambers 8 and 9.

The disinfection chamber 8 has a volume of about 635 L and a working volume of about 548 L. The chamber 8 has an upper region and a lower region, and an inlet pipe 81.

Although not shown, the disinfection chamber 8 has a drain at the lower region.

The inlet pipe 81 extends downwardly from the secondary separation chamber 7 to chamber 8. The inlet pipe 81 is forked and has an intake 83 for a chemical disinfector, such as chlorine tablets. An upper end of the intake 83 has a removable closure so as to allow the introduction of chlorine tablets. The tablets may collect within a capped lower end of the intake pipe 81 and openings 86 in the lower end of the intake pipe 81 allow the chlorine to dissipate throughout the chamber 8.

The manifold 132 of the aerator 13 also extends to the lower region of the disinfection chamber 8. Openings 133 in the manifold 132 allow the escape of air bubbles. These bubbles help mix the wastewater with the chlorine. The wastewater collection chamber 9 has a volume of about 244 L and a working volume of about 112 L. The chamber 9 has an upper region and a lower region, and an inlet pipe 91.

The inlet pipe 91 extends from the disinfection chamber 8 to chamber 9. The inlet pipe 91 is forked and has an air intake port 92 so as to prevent siphoning of wastewater from chamber 9 to chamber 8.

The wastewater collection chamber 9 has at least one (but preferably two) electrical discharge pump 93 for pumping out disinfected water from the chamber 9. The pump 93 is activated by way of a float switch.

The filtration chamber 10 is provided by a cylindrical tank 450. The filtration chamber 10 has an upper region, a lower region and an inlet pipe 101 that extends from the upper region to the discharge pump 93. A containment tap 102 is associated with the inlet pipe 101 and can be moved between open and closed positions.

The filtration chamber 10 contains either a passive filter or an active filter for further polishing the disinfected wastewater. For instance, the chamber 10 could contain a 50 micron sock-type filter, geotextile material, activated charcoal or lime.

The UV chamber 11 is provided by a substantially cylindrical tank 466. The UV chamber 11 has an upper region, a lower region and an inlet pipe 111 that extends from the lower region of the filtration chamber 10. A removable closure 112 is located at the upper region of the chamber 11.

The UV chamber 11 contains a UV lamp for killing microbes, prior to the wastewater being discharged to the sprinkler system 12 (or otherwise discharged to the environment).

In use, inlets 20 are attached to one or more sources of wastewater, taps 38, 75 and 102 are turned to the open position and tap 32 is closed. The inlet pipes 36, 45, 71, 81 and

91 are situated relative to one another such that the natural flow of wastewater is from chamber 3 to chamber 9. The flow rate of the wastewater through the system 1 is approximately 150 L per person per day. Wastewater that is introduced into the homogenisation chamber 2 is homogenised by way of the grinder pumps 21 and pumped to the primary separation chamber 3 by way of inlet pipe 36. Once in the primary separation chamber 3, constituents of the wastewater that are more buoyant or less buoyant than water separate into upper and lower layers, and wastewater intermediate these layers is then fed to aerobic sub-chamber 4 by way of inlet pipe 45.

As wastewater within oxygen-rich sub-chamber 4 makes its way through sub- chamber 5 to sub-chamber 6, it mixes with aerobic microbes and organic matter in the wastewater is consumed by the microbes. The wastewater is then fed from sub-chamber 6 to the secondary separation chamber 7 by way of inlet pipe 71.

Once in the secondary separation chamber 7, constituents of the wastewater that are less buoyant than water settle at the lower region of the chamber 7, and the return pump 76 periodically returns that sediment to the primary separation chamber 3 by way of return line 79.

Wastewater is next introduced into the disinfection chamber 8 by way of inlet pipe

81. The lower end of inlet pipe 81 contains chlorine tablets and these tablets dissolve as wastewater passes through the inlet pipe 81 and through openings 86. Air bubbles from the manifold 132 help mix the wastewater with the chlorine.

Disinfected wastewater that has been fed to collection chamber 9 via inlet pipe 91 is pumped to the filtration chamber 10 via inlet pipe 101 for further polishing.

Wastewater is then fed to the UV chamber 112 by way of inlet pipe 111, whereby microbes within the wastewater are killed. The wastewater is then fed to the sprinkler system 12 for discharge to the environment.

Prior to moving the system 1 to a new location, inlets 20 are detached from the source of wastewater and closed, containment taps 38, 75 and 102 are closed, and the sprinkler system 12 is rolled up and stored. The wastewater need not be pumped from chambers 2, 3, 4, 5, 6, 7, 8 and 9 prior to being moved. Once the system 1 is moved to the new location, inlets 20 are attached to one or more sources of wastewater, the sprinkler system 12 is unrolled, and taps 38, 75 and 102 are turned to the open position. The system 1 may be used immediately. Referring now to figure 2, there is shown a wastewater treatment system 200 according to a second embodiment of the present invention. The system 200 comprises a homogenisation chamber 202, a primary separation chamber 203, an aeration chamber 204, a secondary separation chamber 207, a disinfection chamber 208, a wastewater collection chamber 209, a passive filtration chamber 210, an active filtration chamber 213 , a UV treatment chamber 211, and an aerator 213.

The homogenisation chamber 202 is provided by a top wall 500, a bottom wall 501 and four side walls 502. The homogenisation chamber 202 has an upper region, a lower region and an inlet pipe 224 for wastewater. The chamber 202 has a volume of about 880 L and a working volume of about 525 L. An end of the inlet pipe 224 is attachable to a wastewater source, such as a threaded end of an outlet pipe of a sewage system. Wastewater may either gravity flow to the chamber 202 or be pumped to the chamber 202.

The homogenisation chamber 202 has an electric grinder pump 221 that is activated by way of a float switch. The pump 221 feeds homogenised wastewater to the primary separation chamber 203.

The primary separation chamber 203, the aeration chamber 204 and the secondary separation chamber 207 are provided by a top wall 510, a bottom wall 511, 570, 571, four side walls 512, a first internal wall 321 that separates chambers 203 and 204, and a second internal wall 322 that separates chambers 204 and 207.

The primary separation chamber 203 has a volume of about 1260 L and a working volume of about 1023 L. The chamber 203 has an upper region and a lower region, and an inlet pipe 236. The chamber 203 enables grease etc. to accumulate at the water's surface at the upper region of the chamber 203. The chamber 203 enables faecal matter and other constituents of the wastewater that are less buoyant than water to settle at the lower region of the chamber 3.

A drain (grease trap) 231 is located at the upper region of the chamber 203.

The inlet pipe 236 extends from the grinding pump 221 to a location between the upper and lower regions of the primary separation chamber 203. The inlet pipe 236 has an air intake port 237 so as to prevent siphoning of wastewater from the primary separation chamber 203 to the homogenisation chamber 202. A containment tap 238 is associated with the inlet pipe 236 and can be moved between open and closed positions.

The aeration chamber 204 has an upper region, a lower region and an inlet 245 for wastewater from the primary separation chamber 203. A lower region 556 of internal wall 321 extends towards the homogenisation chamber 202 and together with the bottom wall 511 define the inlet 245. Since the part of the bottom wall 570 providing the first separation chamber slopes downwardly towards the aeration chamber 204, wastewater constituents that have settled on the bottom wall 570 are swept into the aeration chamber 204 by the wastewater flow. The chamber 204 has a total volume of about 3780 L and a working volume of about 3069 L.

The aerator 213 comprises an electrically driven air pump (not shown) and a pipe manifold 232 extending from the pump to the lower region of chamber 204. Openings 233 in the pipe manifold 232 allow bubbles of air to leave the manifold 232 and to travel through chamber 204 when the pump is in operation.

Chamber 204 has a bioactive filter 247, comprising fibre mats, on which aerobic microbes may colonise and grow. A frame or cage 246 extending between walls 321 and 322 hold the filter 247 in position.

The secondary separation chamber 207 has a volume of about 404 L and a working volume of about 238 L. The chamber 207 has an upper region, a lower region, an inlet 271 and a drain 273. The chamber 207 has a top mesh 570 and a bottom mesh 571.

The top mesh 570 captures any large constituents and breaks up the water flow to reduce turbulence inside the chamber 207. The bottom mesh 571 serves to reduce the turbulence from the water flow and helps to reduce the mixing of any settled constituents from a lower region of the chamber 207.

The secondary separation chamber 207 has an electrical sludge return pump 276 for returning settled constituents from the chamber 207 to the primary separation chamber 203. The sloping bottom wall 572 of chamber 207 encourages the movement of settled constituents to the pump 276. A timer periodically activates the pump 276. A return line 279 of the pump 276 extends from the pump 276 to the upper region of chamber 203. The return line 276 has an air intake port 278, so as to prevent siphoning of wastewater from chamber 203 to chamber 207.

The disinfection chamber 208 is provided by a top wall 580, a sloping bottom wall

581 and four side walls 582. The disinfection chamber 208 has a volume of about 635 L and a working volume of about 548 L. The chamber 208 has an upper region, a lower region, an inlet pipe 281 and a drain 282 at the lower region.

The inlet pipe 281 extends from chamber 207 to chamber 208. The inlet pipe 281 has an S-bend 285 and has an intake 283 for a chemical disinfector, such as chlorine tablets. An upper end of the intake 283 has a removable closure so as to allow the introduction of the chlorine tablets. The tablets may collect within a capped lower end of the intake pipe 281 and openings 286 in the lower end of the intake pipe 281 allow the chlorine to dissipate throughout the chamber 208.

The inlet pipe 281 has an air intake port 284, so as to prevent siphoning of wastewater from chamber 208 to chamber 207. A pair of containment taps 287, 288 is associated with the inlet pipe 281 and can be moved between open and closed positions.

The wastewater collection chamber 209 is provided by a top wall 590, a sloping bottom wall 591 and four side walls 592. The wastewater collection chamber 209 has a volume of about 244 L and a working volume of about 112 L. The chamber 209 has an upper region, a lower region, an inlet pipe 291 and a drain 315. The inlet pipe 291 extends from the disinfection chamber 208 to chamber 209.

The wastewater collection chamber 209 has an electrical discharge pump 293 for pumping out disinfected water from the chamber 209. The pump 293 is activated by way of a float switch.

The passive filtration chamber 210 is provided by a cylindrical tank 593. The chamber 210 has an upper region, a lower region and an inlet pipe 301 that extends to the discharge pump 293. A containment tap 302 is associated with the inlet pipe 301 and can be moved between open and closed positions. The chamber 210 contains a passive filter for removing solid constituents from the disinfected wastewater.

The active filtration chamber 213 is provided by cylindrical tank 594. The chamber 213 has an upper region, a lower region and an inlet pipe 313 that extends to chamber 210. The chamber 213 contains an active filter for removing soluble chemicals or for altering the acidity of the disinfected wastewater.

The UV chamber 211 is provided by cylindrical tank 595. The chamber 211 has an upper region, a lower region and an inlet pipe 311 that extends from the filtration chamber 210. The chamber 211 contains a UV lamp for killing microbes, prior to the wastewater being discharged to the environment via outlet pipe 312.

In use, inlet 224 is attached to a source of wastewater, and taps 238, 287, 288 and 302 are turned to the open position. Wastewater that is introduced into the homogenisation chamber 202 is homogenised by way of the grinder pump 221 and pumped to the primary separation chamber 203 by way of inlet pipe 236. Once in the primary separation chamber 203, constituents of the wastewater that are more buoyant or less buoyant than water separate, and wastewater at the lower region of the chamber 203 is then fed to the aeration chamber 204 via inlet 245.

Wastewater within oxygen-rich chamber 204 mixes with aerobic microbes and organic constituents in the wastewater is consumed by the microbes. The bioactive filter 247 speeds up aerobic decomposition of organic matter and filters out solid constituents of the wastewater. The wastewater is then fed from chamber 204 to the secondary separation chamber 207 by way of inlet 271.

Once in the secondary separation chamber 207, constituents of the wastewater that are less buoyant than water settle at the lower region of the chamber 207, and the return pump 276 periodically returns the settled constituents to the primary separation chamber 203 by way of return line 279.

Wastewater is then introduced into the disinfection chamber 208 by way of inlet pipe 281. The lower end of inlet pipe 281 contains chlorine tablets and these tablets dissolve as wastewater passes through the inlet pipe 281 and through openings 286. Disinfected wastewater that has been fed to collection chamber 209 via inlet pipe

291 is pumped to the filtration chambers 210 and 213, via inlet pipes 301 and 313, for further polishing. Wastewater is then fed to the UV chamber 211 by way of inlet pipe

311, whereby microbes within the wastewater are killed. The wastewater is then discharged to the environment via discharge pipe 312.

Prior to moving the system 200 to a new location, inlet 224 is detached from the source of wastewater and closed, and taps 238, 287, 288 and 302 are closed. Once the system 200 is moved to the new location, inlet 224 is attached to a source of wastewater, and taps 238, 287, 288 and 302 are turned to the open position. The system 200 may be used again immediately.

Referring now to figure 3 and 4, there is shown an external view of wastewater treatment system 1. The system 1 comprises a step ladder 620, so as to allow access to the top wall 410, and a hand rail 621 extending along a periphery of the top wall 410.

The top wall includes service hatches 600-604, allowing ready access to the chambers 3- 9.

In the embodiment shown in figure 3, the system 1 includes a transport skid 630 for ready transportation to different locations.

In the embodiment shown in figure 4, the system 1 is located within a 20 foot by 8 foot transport container 700 having sanitary amenities and a 2000 L fresh water tank 710. The water tank 710 supplies water to toilets 701, basins 702, 703 and a shower 704. Wastewater from the amenities is gravity fed to the inlets 20 of the homogenisation chamber 2. The homogenisation chamber 2 can be located correctly under the toilets and can be detached from the rest of the system 1.

The wastewater treatment system of the present invention is mobile, readily transportable and can be put into immediate use straight after transport. It can be readily relocated using a forklift or crane, it can be mounted to a transport skid, it can be mounted to a trailer undercarriage, or it can be permanently mounted to a trailer. The wastewater treatment system of the present invention can be used as a standalone unit, with hose or pipe connections to any sanitary amenities, or it can be built-in as an integrated part of such amenities.

The wastewater treatment system can be up scaled or down scaled according to the number of people it needs to accommodate. An aeration chamber of about 3000 working litres would accommodate 20 people, whereas an aeration chamber of about 900 working litres would accommodate about six people (e.g. suitable for use with a caravan).

Due to the wastewater treatment system's mobility, it can be used at sporting or cultural events, building or construction sites, or at semi-permanent sites such as long- term construction sites, mining villages, caravans etc.

The quality of the discharged disinfected wastewater together with its ease of transport makes it suitable even for remote permanent sites or sites with difficult access, such as mountain resorts.

Whilst the above has been given by way of illustrative example of the invention, many modifications and variations may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein set forth.

The term "comprise" and variants of the term such as "comprises" or "comprising" are used herein to denote the inclusion of a stated integer or stated integers but not to exclude any other integer or any other integers, unless in the context or usage an exclusive interpretation of the term is required.

Claims

1. A portable wastewater treatment system comprising:

an aerator for introducing air into the aeration chamber;

a secondary separation chamber for further separating constituents of the wastewater and having an inlet extending to the aeration chamber;

a disinfection chamber for disinfecting the wastewater, said disinfection chamber having an inlet extending to the secondary separation chamber and an outlet for disinfected wastewater; and

2. The portable wastewater treatment system of claim 1, wherein the homogenisation chamber has a volume of about 400-1000 L.

3. The portable wastewater treatment system of claim 1 or claim 2, wherein the homogenisation chamber inlet is attachable to a conduit of a sewage system.

4. The portable wastewater treatment system of any one of the preceding claims, wherein the homogeniser is a pulverising or grinding pump located within the homogenisation chamber.

5. The portable wastewater treatment system of claim 4, wherein the pulverising or grinding pump is automatically activated by way of a float switch.

6. The portable wastewater treatment system of any one of the preceding claims, wherein the primary separation chamber has a volume of about 800-4000 L.

7. The portable wastewater treatment system of any one of the preceding claims, wherein the primary separation chamber comprises an upper region and a lower region, a drain located at the upper region of the primary separation chamber through which lighter than water constituents may be removed, and a drain located at the lower region of the primary separation chamber through settled constituents may be removed.

8. The portable wastewater treatment system of claim 7, wherein one end of the primary separation chamber inlet extends from the pulverising or grinding pump and another end of the primary separation chamber inlet is situated between the upper and lower regions of the primary separation chamber.

9. The portable wastewater treatment system of claim 8, wherein the primary separation chamber inlet comprising backflow-prevention means for preventing wastewater from backflowing to the homogenisation chamber.

10. The portable wastewater treatment system of claim 9, wherein the backflow- prevention means includes the primary separation chamber inlet comprising an upper region having an air intake port, so as to prevent siphoning of wastewater from the primary separation chamber to the homogenisation chamber.

11. The portable wastewater treatment system of claim 9, wherein the backflow- prevention means comprises a backflow control valve that automatically prevents the backflow of wastewater to the homogenisation chamber.

12. The portable wastewater treatment system of any one of the preceding claims, wherein the aeration chamber has a volume of about 2500-4500 L.

13. The portable wastewater treatment system of any one of the preceding claims, wherein the aeration chamber comprises primary, secondary and tertiary aeration sub- chambers that are separated by upstanding walls or baffles and the sub-chambers are in fluidic communication with one another.

14. The portable wastewater treatment system of any one of the preceding claims, wherein the aeration chamber comprises an upper region and a lower region, a drain located at the upper region of the aeration chamber and a drain located at the lower region of the aeration chamber.

15. The portable wastewater treatment system of claim 14, wherein the aerator comprises an air pump and a manifold extending from the air pump to the lower region of the aeration chamber, and openings in the manifold allow bubbles of air to escape from the manifold into the aeration chamber when the air pump is in operation.

16. The portable wastewater treatment system of any one of the preceding claims, wherein the aeration chamber contains a medium, a filter or a scaffold that aerobic microbes may colonise.

17. The portable wastewater treatment system of claim 16, wherein the medium, filter or scaffold comprises porous geotextile fibre mats, textiles or ceramic tubes that occupy a large volume of the aeration chamber.

18. The portable wastewater treatment system of any one of the preceding claims, wherein the aeration chamber inlet comprises backflow-prevention means for preventing wastewater from backflowing to the primary separation chamber.

19. The portable wastewater treatment system of claim 18, wherein the backflow- prevention means includes the aeration chamber inlet comprising an upper region having an air intake port, so as to prevent siphoning of wastewater from the aeration chamber to the primary separation chamber.

20. The portable wastewater treatment system of claim 18, wherein the backflow- prevention means comprises a backflow control valve that automatically prevents the backfiow of wastewater to the primary separation chamber.

21. The portable wastewater treatment system of any one of the preceding claims, wherein the secondary separation chamber has a volume between about 200-500 L.

22. The portable wastewater treatment system of any one of the preceding claims, wherein the secondary separation chamber comprises a sloping sidewall such that sludge settles in a lower corner of the chamber.

23. The portable wastewater treatment system of any one of the preceding claims, wherein the secondary separation chamber comprises an upper region and a lower region, a drain located at the upper region of the secondary separation chamber, and a drain located at the lower region of the secondary separation chamber.

24. The portable wastewater treatment system of any one of the preceding claims, wherein the secondary separation chamber inlet comprises backflow-prevention means for preventing wastewater from backflowing to the aeration chamber.

25. The portable wastewater treatment system of claim 24, wherein the backflow- prevention means includes the secondary separation chamber inlet comprising an upper region having an air intake port, so as to prevent siphoning of wastewater from the secondary separation chamber to the aeration chamber.

26. The portable wastewater treatment system of claim 24, wherein the backflow- prevention means comprises a backflow control valve that automatically prevents the backflow of wastewater to the aeration chamber.

27. The portable wastewater treatment system of any one of the preceding claims, wherein the secondary separation chamber comprises a return pump for returning settled constituents from the secondary separation chamber to the primary separation chamber.

28. The portable wastewater treatment system of claim 27, wherein the return pump automatically activated by way of a timer.

29. The portable wastewater treatment system of claim 28, wherein the return pump has a return line extending to the primary separation chamber.

30. The portable wastewater treatment system of claim 29, wherein the return line comprises backflow-prevention means for preventing wastewater from backflowing to the secondary separation chamber.

31. The portable wastewater treatment system of any one of the preceding claims, wherein the disinfection chamber has a volume between about 400-800 L.

32. The portable wastewater treatment system of any one of the preceding claims, wherein the disinfection chamber has an upper region and a lower region, a drain located at the upper region of the disinfection chamber, and a drain located at the lower region of the disinfection chamber.

33. The portable wastewater treatment system of any one of the preceding claims, wherein the disinfection chamber inlet comprises backfiow-prevention means for preventing wastewater from backflowing to the secondary separation chamber.

34. The portable wastewater treatment system of claim 33, wherein the backfiow- prevention means includes the disinfection chamber inlet having an upper region having an air intake port, so as to prevent siphoning of wastewater from the disinfection chamber to the secondary separation chamber.

35. The portable wastewater treatment system of claim 33, wherein the backfiow- prevention means comprises a backflow control valve that automatically prevents the backflow of wastewater to the secondary separation chamber.

36. The portable wastewater treatment system of any one of the preceding claims, wherein the disinfection chamber comprises a disinfector for disinfecting the wastewater.

37. The portable wastewater treatment system of claim 36, wherein the aerator further introduces air into the disinfection chamber so as to promote the mixing of the wastewater with the disinfector.

38. The portable wastewater treatment system of any one of the preceding claims, wherein the disinfection chamber outlet comprises backfiow-prevention means for preventing wastewater from backflowing to the disinfection chamber.

39. The portable wastewater treatment system of any one of the preceding claims, wherein the containment valves are associated with at least the homogenisation chamber inlet, the primary separation chamber inlet, the secondary separation chamber inlet, and the disinfection chamber outlet, such that the system may be moved from one location to another without the spillage of wastewater.

40. The portable wastewater treatment system of any one of the preceding claims, wherein the wastewater treatment system further comprises a wastewater collection chamber for collecting disinfected wastewater, said wastewater collection chamber having an inlet extending to the disinfection chamber.

41. The portable wastewater treatment system of claim 40, wherein the wastewater collection chamber has a volume between about 50-300 L.

42. The portable wastewater treatment system of claim 41, wherein the wastewater collection chamber has an upper region and a lower region, a drain located at the upper region of the wastewater collection chamber, and a drain located at the lower region of the wastewater collection chamber.

43. The portable wastewater treatment system of any one of claims 40 to 42, wherein the wastewater collection chamber comprises a discharge pump for pumping disinfected wastewater to a sprinkler system or to yet other chambers for further treatment.

44. The portable wastewater treatment system of claim 43, wherein the discharge pump is automatically activated by way of a float switch.

45. The portable wastewater treatment system of claim 44, wherein the discharge pump has an outlet extending from the wastewater collection chamber.

46. The portable wastewater treatment system of claim 45, wherein the discharge pump outlet comprises backflow-prevention means for preventing wastewater from backflowing to the wastewater collection chamber.

47. The portable wastewater treatment system of any one of claims 40 to 46, wherein a said containment valve is associated with the discharge pump outlet.

48. The portable wastewater treatment system of any one of the preceding claims further comprising chambers having passive or active filters, for polishing the wastewater prior to discharge.

49. The portable wastewater treatment system of any one of the preceding claims, wherein the containment valves may be automatically or manually moved between open and closed positions, wherein in the open position wastewater can flow there through and in the closed position wastewater cannot flow there through.

50. The portable wastewater treatment system of claim 49, wherein the containment valves are hand-operated taps.

51. The portable wastewater treatment system of any one of the preceding claims, wherein the wastewater treatment system comprises at least one housing which provides the homogenisation, primary and secondary separation, aeration and disinfection chambers.

52. The portable wastewater treatment system of any one of the preceding claims, wherein the wastewater treatment system comprises pockets for tines of a forklift or lifting fixtures for lifting with a crane.

53. The portable wastewater treatment system of any one of the preceding claims, wherein the wastewater treatment system comprises a transport skid.

54. The portable wastewater treatment system of any one of the preceding claims, wherein the system is mounted or mountable to a trailer.

55. The portable wastewater treatment system of any one of the preceding claims when integrated in a sanitary amenity.

56. The portable wastewater treatment system of any one of the preceding claims further comprising a strainer to remove large objects prior to the wastewater entering the homogenisation chamber.

57. A portable wastewater treatment system substantially as hereinbefore described with reference to one or more of the accompanying figures.