AU758846B2 - Mobile water treatment system - Google Patents

Description

1298G

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicants: Actual Inventors: Address for Service: Invention Title: Details of Associated Provisional Applications: Provisional Application No.

Filing Date: Title: Kevin Mark WALKOM and John Anthony WALKOM Kevin Mark WALKOM and John Anthony WALKOM HODGKINSON OLD McINNES Patent Trade Mark Attorneys Level 3, 20 Alfred Street MILSONS POINT NSW 2061 MOBILE WATER TREATMENT

SYSTEM

PQ4786 21 December 1999 Mobile Water Treatment System The following statement is a full description of this invention, including the best method of performing it known to us: 1298G/FJ P FIELD OF THE INVENTION The present invention relates to the treatment of polluted water and, in particular, relates to a mobile system for the treatment and recovery of polluted water.

BACKGROUND

Non-permanent work sites such as construction sites and pavement cleaning sites, by their very nature, generally produce a large amount of polluted or waste water. Government and other regulatory bodies have laid down strict guidelines as to the disposal of such waste water.

These guidelines insist that the water be treated in order to remove a large amount of the pollutants and contaminants therefrom, before it can be fed into normal sewerage pipes or disposed of in appropriate manner.

Prior art methods of treating such waste water generally involve large trucks collecting the :polluted water from a number of work sites. The trucks then transport the polluted water to large council water treatment depots, for treatment. The cost of transporting the polluted water from the work site to the nearest council treatment depot, when combined with the council fees for treating the polluted water, are considerable.

OBJECTS OF THE INVENTION It is therefore one non-limiting object of the present invention to provide a water treatment and recovery system which goes at least some way towards overcoming the disadvantages of prior art water treatment systems.

It is a further non-limiting object of the present invention to provide a water treatment and recovery system which is mobile.

I It is an additional non-limiting object of the present invention to provide a water treatment system that is able to collect the polluted water at a work site and treat the polluted water in situ, so that the treated water may be disposed of in ordinary sewerage systems.

SUMMARY OF INVENTION According to one aspect of the present invention there is disclosed a mobile water treatment system including a transport means supporting a polluted water collection means, a water treatment means, and a treated water storage means.

According to one embodiment of the present invention there is disclosed the system substantially as described above wherein the polluted water collection means includes at least one vacuum pump for sucking polluted water through a vacuum hose and into an intermediate storage tank.

Preferably, the water treatment means includes water filtration means. More preferably, the water filtration means includes a plurality of filters including but not limited to a solids filter and a sand filter. Even more preferably, the water treatment means includes at least one filter S through which the polluted water passes.

S Preferably, the treated water storage means includes at least one treated water storage tank.

Preferably, the treated water storage tank has a larger capacity than the intermediate storage tank.

According to another embodiment of the present invention there is disclosed the system substantially as described above wherein the transport means includes at least one wheel.

Preferably, the transport means further includes towing means such that the system may be 0 supported by said at least one wheel as it is towed along by the towing means. Preferably, the towing means includes a connector for a tow bar. Even more preferably, the transport means includes a pair of wheels and a connector for a tow bar to enable the system to be towed behind a vehicle.

According to another aspect of the present invention, there is disclosed the system substantially as described above when used in accordance with the following method: -2- Step 1: Collecting polluted water using the polluted water collection means; Step 2: Treating the polluted water using the water treatment means; Step 3: Storing treated water in the treated water storage means; and Step 4: Transporting the system via the transport means to a dump site and dumping the treated water.

Preferably Step 2 includes the steps of: Passing the polluted water through water filtration means.

More preferably, Step 2 includes the steps of: Repeatedly passing the polluted water through water filtration means.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A detailed description of the preferred embodiment of the present invention will now be described with reference to the following drawings in which: Figure 1 is a side view of the preferred embodiment of the mobile water treatment system of the present invention; and Figure 2 is an enlarged view of the control box of the preferred embodiment of the mobile water treatment system of the present invention.

The preferred embodiment of the mobile water treatment system of the present invention is intended to be used in connection with temporary work sites. Preferably, the water which has been used and polluted on such work sites, is directed for collection and is dammed, in accordance with known methods. In this way the polluted water is prevented from i flowing into storm water drains and the like.

As shown in Figure 1, once the polluted water is collected in a dam the mobile water treatment system may be transported to a point near the dam by connecting the towbar connector to a towbar of a vehicle and towing the system to the dam. As shown in Figure 1, the preferred system includes an axle and a pair of wheels However other wheel arrangements are also possible.

-3- Once the system is in place, a first end (10) of a vacuum hose is placed beneath the surface (11) of the polluted water When the system is turned on using the main power switch (12) in the control box (13) [see Figure 2] a vacuum pump (14) at a second end (15) of the vacuum hose begins to suck the polluted water through the vacuum hose and into an intermediate storage tank (16).

In the preferred embodiment, the intermediate storage tank (16) has a low level water probe (17) which protrudes from an inner surface (18) of the intermediate storage tank This low level water probe (17) is able to detect when the water level (19) in the intermediate storage tank (16) falls below a predetermined minimum level In the preferred embodiment, the intermediate storage tank (16) also includes a high level water probe situated proximate an upper end (21) of the intermediate storage tank This high level water probe (20) is able to detect when the water level (19) in the intermediate storage tank (16) reaches a predetermined maximum level (22).

In use, when the high level water probe (20) detects that the water level (19) in the intermediate storage tank (16) has reached the predetermined maximum level (22) a submersible water pump (24) is turned on and sucks the polluted water in the intermediate storage tank (16) through a first pipe As the polluted water passes up the first pipe it initially passes through a non-return valve followed by a solids filter (27) and into a sand filter As the polluted water passes through the solids filter the pollutant solids (29) are removed from the polluted water As the polluted water (2) passes through the sand filter micro-solids (30) are removed from the polluted water (2) and most chemicals (31) are rendered inert.

A filter control unit (55) automatically controls the operation of the sand filter The Spolluted water passes down through a central pipe (56) and into the filter body (57) which is substantially filled with sand The polluted water then passes up through the sand (58) in the filter body (57) and as it does so, the pollutants are removed and the polluted water becomes treated water (36).

Having passed through the sand filter the treated water (36) then passes through a second pipe into a main storage tank In the preferred embodiment, the main storage tank (34) has a larger storage capacity than the intermediate storage tank (16).

In the preferred embodiment, when the low level water probe (17) in the intermediate storage tank (16) detects that the water level (19) in the intermediate storage tank has fallen below the predetermined minimum water level the submersible water pump (24) is stopped and the vacuum pump (14) begins to refill the intermediate storage tank (16) by sucking polluted water from the dam up through the vacuum hose In the preferred embodiment, the main storage tank (34) includes a high water level probe (38) proximate its upper end. This high water level probe (38) is able to detect when the water level (40) in the main storage tank (34) exceeds a predetermined maximum water level (41).

In use, when the high water level probe (38) detects that the maximum water level (41) has been reached, the system automatically switches off and the system can then be towed via the towbar connection to an authorised drop-off point, where the treated water (36) can be dumped into the sewer drain, via a waste water outlet (42) situated proximate a lower end i (43) of the main storage tank (34).

SDuring the filtering process the sand (58) in the filter body (57) will occasionally become coagulated, requiring increased water pressure to allow the polluted water to pass through it. In the preferred embodiment when the filter control unit (55) detects such an increase in pressure it causes polluted water to pass through the sand (58) in the sand filter in the opposite direction. That is, when the filter control unit (55) detects that the pressure has passed a predetermined upper limit, it activates a backwash switch (59) which causes the polluted water from the intermediate storage tank (16) to pass down through the sand filter body (57) and up through the control pipe (56) in the opposite direction to the arrow shown.

The treated water (36) then passes through pipe (35) and into the main storage tank This backwashing of the sand filter frees up the sand so that the polluted water can then pass through the said filter (28) at a predetermined normal pressure.

In the preferred embodiment, the control of the system is governed by an automatic process controller (37) stored in the control box (13) and requires little or no human intervention other than the starting and restarting of the system.

In the preferred embodiment, the system is enclosed within a canopy (44) and is powered by a 3.5kVA generator (45) which is either positioned adjacent the towbar connection or within the canopy (44) adjacent the intermediate storage tank The preferred embodiment also includes a warning light (46) preferably situated on the top (47) of the canopy (44) which switches on when the high water level probe (38) in the main storage tank (34) is activated. The preferred embodiment also includes a trailer hazard light (48) which is activated when the system is connected to the vehicle and is being towed along. The preferred embodiment also includes an internal light (49) in order to illuminate the interior of the canopy (44).

The control box (13) of the preferred embodiment not only includes a main power switch (12) but also includes a light switch a 12 volt reduced power point for the traffic control signals (51) and a pair of 240 Volt power points The preferred embodiment also includes control switches (53) for the water probes and pumps, together with a set of 240 Volt circuit breakers (54).

ooooo ~Although the invention has been described with reference to a preferred embodiment, including drawings, it will be recognised by persons skilled in the art that numerous variations and modifications may be made to the invention as broadly described herein without departing from the overall spirit and scope of the invention.

o• 999999 ooo..i

Claims (13)

1. A mobile water treatment system including: an intermediate water storage tank having an inlet and an outlet, and a submersible pump for pumping water through the outlet; a high level water probe disposed in the intermediate storage tank, the probe providing a signal in response to the water level in the intermediate storage tank rising above a predetermined level; a low level water probe disposed in the intermediate storage tank, the probe providing a signal in response to the water level in the intermediate storage tank falling below a predetermined level; a water pump disposed intermediate the intermediate water storage tank inlet and a polluted water reservoir, the pump moving polluted water from the reservoir to the intermediate water storage tank; an in-line solids filter having an input and an output wherein the input is disposed in fluid communication with the output of the intermediate water storage tank; a sand filter having an input in fluid communication with the output of the solid filter; a main water storage tank having an inlet in fluid communication with an outlet of the sand filter, the main water storage tank having a high water probe which provides a •signal in response to the water level in the main water storage tank exceeding a predetermined level; a backwash path in the sand filter such that when the pressure in the sand filter exceeds a predetermined level water is forced in a reverse path through the sand filter to the main water storage tank by a sand filter controller; and a system controller for controlling the water treatment system such that the controller deactivates the water pump in the intermediate storage tank in response to the signal generated by the high water level probe in the main water storage tank.

2. A mobile water treatment system according to claim 1 further including a one- way valve disposed intermediate the output of the intermediate water storage tank and the input of the solids filter.

3. A mobile water treatment system according to claim 1 or 2 including a second water pump disposed intermediate the intermediate water storage tank and the polluted water reservoir.

4. A mobile water treatment system according to any one of claims 1 to 3 including a generator for providing power to the system.

A mobile water treatment system according to any one of the preceding claims wherein the system is mounted on a trailer which is configured to be towed by an automobile.

6. A mobile water treatment system according to any one of the preceding claims S wherein the main water storage tank has a greater capacity than the intermediate storage tank.

7. A method according to any one of claims 1 to 6 wherein the water in the main water storage tank is suitable to be disposed of in a sewerage or stormwater system. S

8. A method of treating water using the mobile water treatment system as defined in any one of claims 1 to 6, the method including the steps of: pumping polluted water from the polluted water reservoir into the intermediate water storage tank; i: pumping water from the intermediate water storage tank through the in-line solids filter; pumping the water from the output of the in-line solids filter through the sand o filter; passing water from the output of the sand filter into the main storage tank.

9. A method according to claim 8 wherein water is pumped from the intermediate water storage tank through the in-line and sand filters to the main storage tank in response to a signal from the high level water probe in the intermediate storage tank.

A method according to claim 8 or 9 further including the step of measuring the pressure in the sand filter and, when the pressure exceeds a predetermined level, pumping water through the backwash path of the sand filter to the main storage tank.

11. A method according to any one of claims 8 to 10 further including the step of disabling the mobile water treatment system in response to the signal generated by the high water level probe in the main water storage tank.

12. A mobile water treatment system as substantially hereinbefore described and with reference to the accompanying drawings.

13. A method of treating polluted water as substantially hereinbefore described and with reference to the accompanying drawings. Dated this 2 nd Day of January, 2003. KEVIN MARK WALKOM and JOHN ANTHONY WALKOM HODGKINSON OLD McINNES Patent Attorneys for the Applicant