AU727124B2

AU727124B2 - Water supply and filtration system

Info

Publication number: AU727124B2
Application number: AU67923/96A
Authority: AU
Inventors: Lawrence Ernest Eaton
Original assignee: JAMES NORMAN ATKINSON
Current assignee: JAMES NORMAN ATKINSON
Priority date: 1995-09-29
Filing date: 1996-09-30
Publication date: 2000-11-30
Anticipated expiration: 2016-09-30
Also published as: AU6792396A

Description

P/00/011 Regulation 3.2 a

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Actual Inventor: Address for Service: LAWRENCE ERNEST EATON Lawrence Ernest Eaton

INTELLPRO

Patent Trade Mark Attorneys Level D, 308 Edward Street BRISBANE, QLD, 4000 (GPO Box 1339, BRISBANE, 4001) Invention Title: "WATER SUPPLY AND FILTRATION SYSTEM" Details of Associated Provisional Application No: Australian Patent Application No. PN5697 filed 29 September 1995.

The following statement is a full description of this invention, including the best method of performing it known to me: I f 2 THIS INVENTION relates to a water supply and filtration system and in particular but not limited to a water supply and filtration system employing a filter media and backwash means for the purpose of sterilising/reactivating the filter media.

In one aspect the present invention resides in a method of in-line filter media sterilisation where a filter cartridge containing filter media is fitted in a water supply line, the method comprising the steps of:- Isolating the filter cartridge from the water supply line; (ii) Supplying a sterilising/reactivating agent to the filter cartridge for

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10 the purpose of sterilising/reactivating the filter media; (iii) Subsequently re-connecting the filter cartridge to the supply line in the reverse flow direction to backwash the filter to clear the agent; and (iv) Subsequently reconnecting the filter to the supply line for forward flow of water through the filter.

In a further aspect the invention resides in a water supply and filtration system employing in-line sterilisation/reactivation of a filter media, the system comprising, a main supply line communicating with a source of water under pressure, a filter cartridge holding the filter media through which water from the supply line flows in a first direction to an outlet for use, a backwash circuit comprising valves, pipes and a waste outlet enabling redirection of water flow through the filter cartridge in a direction opposite the first direction and to the waste outlet, and a source of sterilising/reactivating agent selectively communicating with the cartridge.

The filter cartridge can be any suitable cartridge designed to hold filter media of any known kind.

The backwash circuit is typically arranged as a consequence of post fitting the filter cartridge in an existing water supply line, the filter cartridge being fitted in a parallel line having a parallel line inlet from the main supply line with a main stop valve located in the main supply line downstream of the parallel line inlet and an isolation stop valve between the parallel line inlet and the cartridge, o a stop valve to the waste outlet and a control means for selective delivery of the agent to the filter cartridge.

o 10 In normal use the main stop valve is closed, the isolation stop valve open, the waste stop valve closed and the control means closed so that water flows through the filter in the said first direction. When the system is set up for sterilisation the filter is isolated by closing the main valve and the isolation valve and opening the waste outlet valve. The control means is then operated to deliver a predetermined quantity of the sterilising/reactivating agent to the filter cartridge and the waste water outlet is closed and the system stands while the sterilisation/reactivation process takes place.

Next with the isolation valve still closed the main valve is then opened and the filter backwashed through the waste outlet. The waste valve and main valves are then closed. The isolation valve is opened and normal use is resumed.

The sterilisation/reactivation agent can be any suitable agent known for its sterilisation/reactivation properties. A typical agent is hydrogen peroxide as a solution. The filter media can be activated carbon although other media can be used.

The source of steri I isation/reactivation solution can be a supply fitted to the cartridge either temporarily or a permanently fitted container can be employed which is charged with the agent prior to use. Preferably a disposable cartridge or a refillable container is employed. Typically a refillable hermetic container is employed so that pressure generated within the container by the steri I isation/reactivation process results in the agent being supplied to the cartridge under pressure at least while the waste outlet valve is open. The container preferably includes a guide means such as a neck projecting into the container while the agent flows through side passages in the guide means inhibit the bubbling action from resisting flow of agent to the cartridge.

In typical applications of the present invention a pair of filters are arranged in parallel so that there is an uninterrupted supply of filtered water while the filters are being sterilised. In this arrangement the filters can be ,.steri I ised/reactivated alternately.

Preferably, the system employs an ozone injection means positioned upstream of the backwash circuit.

In order that the present invention can be more readily understood and be put into practical effect reference will now be made to the accompanying drawings which illustrate a preferred embodiments of the present invention and wherein:- Figure 1 is a perspective view of a filter and associated reservoir for charging with a sterilisation/reactivation agent; Figure 2 is a longitudinal section through the assembly of Figure 1; Figure 3 is a side view of the assembly of Figure 1; Figure 4 is an end view of the assembly of Figure 1; Figure 5 is a section through 5-5 of Figure 3; Figure 6 is a schematic circuit diagram of a water supply and filtration system according to the present invention and employing the assembly of Figure 1; o Figure 7 is a drawing similar to Figure 6 but where the filter is arranged

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S°vertically rather than horizontal; and Figure 8 is a circuit diagram of a dual filter system employing the teachings of the present invention.

Referring to the drawings and initially to Figures 1 to 5 there is illustrated an assembly 10 that can be retro fitted to an existing domestic water supply to provide filtration and periodic sterilisation and reactivation of a filter media located within the filter cartridge 11. The assembly 10 includes a filter cartridge C. 11 to be retained in place using a pair of clamps 12 and 13. A reservoir 14 communicating with the cartridge 11 can be charged with an agent such as a hydrogen peroxide solution so that the filter media 15 and the cartridge 11 can be sterilised and reactivated. The filter media in this case is activated carbon and is housed between two perforated disks or screens 16 and 17. The inlet to the filter is illustrated at 18 and the outlet at 19. The reservoir 14 is located on the outlet side of the filter so that when the cartridge 11 is isolated and sterilisation completed the whole length of the supply system where the sterilisation agent has been employed can be backwashed and cleared.

The reservoir 14 includes a lid 19 enabling the reservoir to be hermitically sealed so that pressure can be generated above the sterilisation agent at 20 as process gases percolate up through neck opening 21 forming an annular ring of pressure on the agent within the reservoir 14 so that the agent is forced through inlet hole 21a to track down the inside walls of the neck 21 so the remaining agent held within the reservoir 14 flows into the cartridge under pressure notwithstanding gas percolating up through the neck 21. This occurs when a Svalve shown at 22 is open to enable flow of the agent down into the cartridge 11.

This will be explained in greater detail below.

The capacity of the filter and the reservoir 14 can vary according to the application with smaller and larger domestic units being applicable. Still larger 10 industrial units can be employed but generally speaking the reservoir 14 is matched in volume and capacity to the filter cartridge 11.

Referring now to Figure 6 there is illustrated a water supply and filtration system 23 employing an assembly 10. A typical installation is shown in Figure 6 where a main water supply line 24 communicates with an outlet 25 via a faucet 26. The assembly 10 has been retro-fitted to provide filtered water, in this case filtered cold water through the outlet 25, there also being provided a hot water faucet 27 delivering unfiltered hot water to the outlet A back flow prevention valve 28 is provided upstream of the parallel line connection 29 to the filter cartridge 11. A stop valve 30 causes flow to be diverted from the main supply line 24 through an isolation valve 31 to the filter cartridge 11 then through the pipe 32 and ultimately to the outlet 25 through the faucet 26. Stop valve 33 is employed as shown so that when the isolation valve 31 is closed and the faucet 26 is closed water from the main supply line 24 can flow in the reverse direction through the cartridge 11 and out through the waste outlet at 34. Thus it will be realised that the embodiment illustrated in Figure 7 allows for the filter cartridge 11 to be backwashed.

When it is desired to sterilise and reactivate the carbon filter contained within the cartridge 11 the cartridge 11 is isolated by closing off valves 30 and 31. The reservoir 14 is charged with 5% hydrogen peroxide solution or other suitable steriliser/reactivator and the valve 22 opened until such time as of flow o liquid at the waste outlet 34 ceases. As the reservoir 14 is hermetically sealed, i•o as gas is produced in the sterilisation/reactivation process the gas and reactants bubble and flow to the top of the reservoir 14 and as described above pressurised 10 hydrogen peroxide solution within the reservoir is forced down into the cartridge 11 despite any reaction that would otherwise inhibit this flow. At this time the ~stop valve 33 and valve 22 are also closed so that the sterilisation process occurs under pressure.

o Once the sterilisation/reactivation process is completed the valve 30 is opened, the valve 33 is opened and the cartridge 11 is backwashed until all the hydrogen peroxide solution and reactants are removed. The valve 33 is then closed the valve 30 closed and the valve 31 opened and filtration occurs according to normal procedures.

Figure 7 is an all material respects the same as the embodiment of Figure 7 except that the cartridge for the reservoir 14 is now located ostensibly in line with the filter cartridge 11 but the filter cartridge 11 is now positioned vertically.

Where appropriate like numerals have been used to illustrate like features.

Referring now to Figure 8 there is illustrated a further embodiment of the present invention wherein a single reservoir 14 is employed to service two filter 8 cartridges 11 arranged in parallel.

Figures 9 and 10 illustrate further application of the present invention where the supply installation includes provision for injection of ozone into the water line upstream of the filter.

Whilst the above has been given by way of illustrative example of the present invention, many variations and modifications thereto will be apparent to those skilled in the art without departing from the broad ambit and scope of the invention as set forth in the appended claims.

Claims

1. A method of in-line filter media sterilisation where a filter cartridge containing filter media is fitted in a water supply line upstream from a main outlet, the method comprising the steps of:- isolating the filter cartridge from the water supply line; (ii) supplying a sterilising/reactivating agent to the filter cartridge for the purpose of sterilising/reactivating the filter media; (iii) subsequently reconnecting the filter cartridge to the supply line in the reverse flow direction to backwash the filter to clear the agent; and (iv) subsequently reconnecting the filter to the supply line for forward flow of water through the filter.

2. The method according to claim 1 wherein there is provided a backwash circuit comprising a control valve for controlling delivery of said agent, an isolation U.. valve upstream of the cartridge and a waste outlet valve upstream of the cartridge, pipes and a waste outlet enabling reverse flow through the filter cartridge and to the waste outlet, the method comprising the following steps:- holding the said agent in a container downstream of the filter cartridge; closing the isolation valve; opening the waste outlet valve; opening the control valve; subsequently closing the waste outlet valve for a predetermined period of ti me while the sterilisation/reactivation process takes place; subsequently opening the waste outlet valve and causing water from the water supply line to flow in the reverse direction through the filter cartridge and to the waste outlet to flush the agent from the filter cartridge; and subsequently closing the control valve and the waste outlet valve and opening the isolation valve for normal forward flow through the filter cartridge.

3. A water supply and filtration system employing in-line sterilisation/reactivation of a filter media, the system comprising a main supply line communicating with a source of water under pressure, a filter cartridge holding the filter media through which water from the supply line flows in a first direction to po an outlet for use, a backwash circuit comprising valves, pipes and a waste outlet enabling redirection of water flow through the filter cartridge in a direction opposite the first direction and to the waste outlet and a source of sterilising/reactivating agent arranged to change the cartridge whenever required, when the cartridge is not delivering water to the outlet for use.

4. The water supply and filtration system according to claim 3 wherein the filter cartridge is fitted in a parallel line having a parallel line inlet from the main supply line with a main stop valve located in the main supply line downstream of the parallel line inlet and an isolation stop valve between the parallel line inlet and the cartridge, a stop valve to the waste outlet and a control means for selective delivery of the agent to the filter cartridge. 11 The method according to claim 1 employing the water supply and filtration system of claim 4 wherein, in normal use, the main stop valve is closed, the isolation stop valve open, the waste stop valve closed and the control means closed so that water flows through the filter in the said first direction, when the system is set up for sterilisation, the filter is isolated by closing the main valve and the isolation valve and opening the waste outlet valve, the control means is then operated to deliver a predetermined quantity of the sterilising/reactivating agent to the filter cartridge and the waste water outlet is closed and the system stands while the sterilisation/reactivation process takes place, next with the isolation valve still closed the main valve is then opened and the filter backwashed through the waste outlet, the waste valve and main valves are then closed, the isolation valve is opened and normal use is resumed. wherein the source of sterilisation/reactivating solution is a hermetic container employed so that pressure generated within the container by the sterilisation/reactivation process results in the agent being supplied to the filter cartridge under pressure.

7. The water supply and filtration system according to claim 6 wherein the :container includes and agent guide means projecting into the container and having back flow or bubbling action arising from reaction downstream of the container can percolate up through the main passage. 12

8. A water supply and filtration system according to any one of claims 3, 4, 6 or 7 wherein a pair of filter cartridges are arranged in parallel so that there is an uninterrupted supply of filtered water while the filters are being sterilised, the filters being arranged so that they can sterilised alternately.

9. A water supply and filtration system according to any one of claims 3, 4, 6, 7 or 8 wherein an ozone injection means is positioned upstream of the backwash circuit. DATED this 2 6 t h day of September 2000 LAWRENCE ERNEST EATON By his Patent Attorneys INTELLPRO