WO2011131919A1

WO2011131919A1 - A water filtration, purification and storage unit capable of serving a community of 2000 people or for use in disaster and relief situations

Info

Publication number: WO2011131919A1
Application number: PCT/GB2011/000472
Authority: WO
Inventors: Leighton Harris James
Original assignee: Leighton Harris James
Priority date: 2010-04-19
Filing date: 2011-03-30
Publication date: 2011-10-27
Also published as: GB2479729A; GB2479729B; GB201006471D0

Abstract

A portable filtration and chlorinisation system intended for the purification of non-saline water drawn from a variety of sources e.g. surface water, river, borehole etc. to drinking water conditions. This is achieved by the already flocculated water passing through two primary filters. Chlorinisation takes place by the use of a water-driven dosing pump capable of dosing at the rate of 2ppm and upwards as required. The water then passes through its final stage of purification where use is made of an advanced filter media. This media is self -sterilising because of its permanent high surface catalytic properties and negative zeta potential. The negative zeta potential allows the filter media to adsorb positive charged metal ions from the water such as iron and manganese. The water having passed through this filter is of micron or sub - micron standard. The treated water is then stored in an incorporated holding tank ready for later use as and when required. This stored water is used when it becomes necessary to backwash the system. Such a high degree of efficiency has been achieved in the backwashing system that the filter media will never need to be replaced. Further polishing of the water may be achieved though the use of a specially designed activated carbon system which brings the water to bottled water standards. According to a second aspect of the present invention, this water treatment unit is carried on a trailer which incorporates its own specially designed flocculation and header tank rendering the unit of special usefulness in disaster and relief situations and also for the military on manoeuvres etc. Both systems as described produce 1000 litres per hour of good potable water meeting the needs of small communities of approximately 2000 people.

Description

A water filtration, purification and storage unit capable of serving a community of 2000 people or for use in disaster and relief situations.

DESCRIPTION

The invention relates to a stand-alone water filtration, purification and storage unit.

Water filtration and purification is well known being undertaken using a variety of methods. Most methods are relatively expensive in their on-going operation, necessitate electrical power to operate and the regular replacement of filter media.

Such units seldom carry any storage capacity for the treated water and operate in-line with the normal domestic or public water system.

According to the present invention the stand-alone unit operates without the use of electrical power, needs no expensive filter media replacement and that over a long period of time, due to a high efficiency back-wash system. The treated water is stored ready to be drawn off for consumption. Residual chemical treatment and any colourisation are dealt with in the final stages of the units¹ operation.

With the easily transported and easily installed system, sufficient good potable water is produced, sufficient for the needs of 2000 people even in the most remote location.

A specimen embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which :-

Figure 1/6 shows the combined header and flocculation tank in perspective to the main unit.

Figure 2/6 shows a plan of the main chlorinisation, filtration and activated carbon units within the system.

Figure 3/6 shows the top elevation of the main tank.

Figure 4/6 shows the side elevation of the main tank.

Figure 5/6 shows the newly designed innovative activated carbon unit.

Figure 6/6 shows the mobile unit with the incorporated header tank in operation.

Referring to the drawings, water can be gathered in the combined header/flocculation tank (1) from a variety of sources (2), rivers, surface water and a borehole. For the water to be introduced into the header tank (1), a small hand pump would be sufficient. A minimum head of water (3) of one metre is required. Water entering the combined header/flocculation tank (1) initially enters the flocculation section where a suitable quantity of flocculent is added by means of a small dosing unit to meet the requirements of the quality of water to be treated. A sufficient time lapse is necessary to allow the suspended particles to coagulate and settle at the bottom of the flocculation section from which it will be removed via a drain plug situated at the bottom of the tank. After the completion of the settlement time, the treated water flows into the header section of the tank.

Water from the combined header/flocculation tank (1) enters the inlet flow control valve (4). At this juncture larger suspended particles in the water are deposited out. The water proceeds through a water driven chlorine dosing pump (7) after passing through the pre-filtration on the unit (5)and(6).

Particles deposited within filters (5) and (6) are removed by shaking and washing the filter fibres.

The water enters the final stage of filtration (9) where it passes through the filter media

(10) . The water then passes through its final stage of purification where use is made of an advanced filter media. This media is self -sterilising because of its permanent high surface catalytic properties and negative zeta potential. The negative zeta potential allows the filter media to adsorb positive charged metal ions from the water such as iron and manganese. The water having passed through this filter is of micron or sub - micron standard. Flow rate will depend on the characteristics of the source water, and is controlled by adjustment of the inlet flow control valve (4). The water storage section

(11) is interconnected with final filtration chamber (9) by a flow baffle(12) which is designed to provide even distribution of water under both normal flow and backwash conditions.

Once the storage section (11) is filled to the top water level and remains unused, flow is automatically stopped from the chlorinisation unit (7) using a reverse ball valve arrangement (8) so avoiding the wastage of chemicals and unnecessary debris load on the filter bed (10).

The draw-off valves (13) & (14) are provided on the storage section (11). Valve (14) takes water directly from the water storage section (11). A water test kit is provided which allows the operator to assess and adjust the chemical dosage as required by use of the micro switch on the chlorinisation unit (7). At this stage the water is both potable and may be used for other general purposes e.g. cooking and is of the same quality as our mains tap water.

Valve (13) takes water from the storage compartment (11), which has first passed through the silver impregnated carbon stack (15).

After exhaustive tests using commercially available activated carbon units, it has been found that they were not to purpose due largely to their restrictive nature causing a great decrease in water flow. These activated carbon units normally function in systems where large water pressure is made available. The present invention operates without the use of electricity and requires only 1 metre heads of water (0.1 BAR). This has in turn necessitated a completely new activated carbon stack arrangement to be designed.

See Figure 5/6

With the top sealing unit removed, together with the ring assembly, the activated carbon held in the nylon holding bag is introduced into the outer assembly and pushed firmly to the bottom where it sits upon a perforated block which ensures that the water entering from the chlorinated tank (11) immediately flows uniformly up through the activated carbon. This perforated block also serves to keep the bottom of the activated carbon bag against the wall sides and the base.

The ring assembly is replaced and sits on the lugs. This ensures that the top sealing unit sits in the outer assembly both firmly and at right angles to the vertical. By the operation of the open/closing sealing unit handle a water tight condition is obtained as pressure is exerted on the potable water compatible rubber seal. With the introduction of the inlet water from (11) the rising water causes an air block which is relieved via the air bleed. When the rising water has reached the top of the unit the air bleed is closed and the unit is ready for use. Water can now flow through exit valve (13).

To maintain the required water flow and to allow sufficient time for water and activated carbon contact a special activated carbon has been utilised (PHO 6 x 12 0.05Ag Special).

In this way any residual taste of chlorine is removed and the water receives its final polish and in appearance and quality is of the same standard as bottled water

A flow meter (20) is incorporated in line to indicate any reduction of water flow necessitating the back-washing of the system.

Occasionally the advanced filter media will require cleaning when debris is sufficient to choke the system. This is easily accomplished by closing all valves and opening the backwash valve (16) alone, allowing the filter media (10) to clean itself under reverse water flow using the clean water contained in the water storage section (11). After 15/30mins the inlet valve (4) and backwash valve (16) are reversed so bringing the unit back into operation.

The main body of the unit (19) is fabricated from polypropylene sheet which has been approved for both food and water contact.

Access is gained to the chlorinisation pump (7), filters unit (5) and (6), the activated carbon stack (15) and the flow metre (20) by means of two doors, (17) located at the top of the unit and (18). A mobile unit has been designed and developed to deal with emergency and disaster situations and which also makes the unit suitable for military purposes etc.

See Figure 6/6

The operation to make the unit ready for use is carried out by two people. The unit is capable of producing safe, clean drinking water at the rate of lOOOIitres per hour within three hours of arriving on site. The unit as described is contained in a trailer unit and comprises a petrol driven/solar panel water pump which supplies water to the collapsible water tank. The water is then piped via gravity to the unit where it is filtered and purified and made ready for consumption. Figure 6/6 shows the mode of operation to bring the unit to a state of readiness for operation

To Accompany Figure 5/6

Activated Carbon Stack specifically designed to meet the requirements of this Stand-alone Water Filtration,

Purification and Storage Unit.

(a) Operating handle to open/close the sealing unit

(b) Air Bleed

(c) Sealing unit

(d) Rubber seal ( Compatible with potable water use)

(e) Ring assembly

(f) Lug

(g) Outer nylon holding bag

(h) Inner porous bag

(i) Polypropylene outer assembly stack (15)

(j) Inlet water from storage tank (11)

(k) Activated carbon (PHO 6 x 12 0.05 Ag Special)

(1) Perforated block to ensure uniform distribution of water up through

Activated carbon

(m)Exit water to valve 13.

Claims

5 Claims

1. A stand-alone water filtration, purification and storage unit comprising a flocculent/ header tank for receiving water to be treated, at least one filter means, a chlorine dosing unit downstream of the at least one filter means, a further filter means downstream of the chlorine dosing unit and a storage tank for storing the purified water, wherein the stored purified water can be utilised to provide a backwashing operation and the unit is capable of fulfilling all its operations of filtration, purification, storage and backwashing without the use of electrical power.

2. A stand-alone water filtration, purification and storage unit as of claim 1, which comprises two filter means upstream of the chlorine dosing unit.

A stand-alone water filtration, purification and storage unit as of claim 1 or claim 2, wherein the filter means upstream of the chlorine dosing unit are removable to facilitate cleaning.

A stand-alone water filtration, purification and storage unit of any preceding claim, which may be manually transported through the use of the handles positioned at the four corners of the unit and easily installed in remote locations providing sufficient potable water for the needs of 2,000 people.

A stand-alone water filtration, purification and storage unit substantially described herein with reference to figures 1/6 to 4/6.

6. A stand alone water filtration, purification and storage unit substantially described herein with reference to figure 1/6 to 4/6 with the facility to further polish the filtered and chlorinated water by passing it through a specially designed activated carbon unit to fit purpose.

7. A stand alone water filtration, purification and storage unit substantially described herein with reference to figure 1/6 to 4/6 mounted when necessary on a trailer unit which incorporates a petrol driven/solar panel pump which supplies water to the collapsible water tank.