WO1999058222A1

WO1999058222A1 - Solids separator

Info

Publication number: WO1999058222A1
Application number: PCT/AU1999/000344
Authority: WO
Inventors: Gregory Leslie Lewis
Original assignee: Gregory Leslie Lewis
Priority date: 1998-05-07
Filing date: 1999-05-07
Publication date: 1999-11-18
Also published as: NZ335559A; AUPP336098A0

Abstract

A solids separator provides a filter in bag form (10) fitted at a tank (11) inlet (14) to pass water, effective to hold sludge pending replacement or cleaning. The bag (10) provides sufficient filter material above a full water line (15) to the storage vessel to enable flow therethrough without unacceptable impedance and sufficient of the solids separator to store build up of sludge to enable a useful period of time between replacement or cleaning. It can be adapted to be removably hung beneath a coarse mesh separator (21) at the inlet (14) to the storage vessel. It can have an outlet to enable cleaning by flushing (41). It may be dimensioned with a length greater than the height of the storage vessel and a substantially uniform diameter there-along. It may comprise a number of separating bags (16, 18, 20) of increasing separative ability, nested, in use, one inside the other.

Description

TITLE: SOLIDS SEPARATOR

FIELD OF THE INVENTION

THIS INVENTION relates to improvements in the

separation of solids and/or fines from a flow of fluid that otherwise

might enter, along with the fluid, into a storage volume for the fluid

and accumulate therein. The invention finds particular application in

the filtering of rain water, collected, typically but not exclusively, off

a roof, to improve the cleanliness of the inside of storage volumes

such as rain water tanks, and the like.

BACKGROUND TO THE INVENTION

Rain water collection and storage, in a suitable vessel,

typically a tank in corrugated iron, of fibreglass or concrete, is a

widely used means of establishing a supply of household water. The

cleaner the storage vessel remains, the more suitable the water will

be for consumption and other household activities.

The current methods and apparatus by which to achieve

the goal of maintaining cleanliness have been successful only in

removing large solid objects i.e. leaves and twigs etc., this being

achieved typically by placing one or more coarse mesh screens at

strategic points in the flow of fluid to a vessel, typically positioned as

a leaf strainer at outflow of roof guttering, and as an insect barrier, 2 typically at the inlet to the vessel. An additional approach to

maintaining cleanliness involves adaptations to the system of

collection whereby the first quantity of rain water is diverted from the

storage vessel, but this only prevents initial dust and foreign matter

from entering the vessel.

OBJECT OF THE INVENTION

It is an object of the invention to further improve the

cleanliness of fluid flowed to a storage vessel by a means which

might operate independently of existing techniques or operate

together with them to supplement their operation. The invention in a

preferred form has an additional object of not only enabling removal

of the collected material by removal of the solids separator but also

the cleaning of the solids separator for reuse. Other objects and

particular advantages will hereinafter become apparent.

DESCRIPTION OF THE INVENTION

The present invention addresses the above stated

problems with a solids separator which comprises one or more of a

separating receptacle, sack, sock, bag, cone or the like (hereinafter

generally referred to as a bag, or being in bag form, for convenience,

it being intended that the term bag will encompass all of the aforesaid

where context does not specify something more specific), in a 3 material acting as a filter, sieve or screen (hereinafter referred to as a

filter material for convenience, it being intended that any of the

aforesaid functions are encompassed by the term), to be loaded into

or fixed in place, in use, in a fluid flow to a storage vessel at a

strategic point, either in the storage vessel or the conduits or flow

paths to the storage vessel. In a preferred form, the solids separator

is located down stream of a coarse mesh separator, of the usual kind,

typically located at the inlet to the storage vessel. In a particular

preferred form, the solids separator is ideally suspended inside the

storage vessel, effective to separate a targeted quantity of the

remaining solids from the fluid, holding the solids until cleaning or

replacement of the sock is implemented. It will be clear to those

skilled in the art that the degree of additional filtering which is

effected is determined by the qualities and attributes built into the

solids separator, there being a variety of filter or screening materials

available to be used and a range of particle sizes able to be effectively

targeted by suitable choice of filter or screening material.

The solids separator may be a usual filter material, in bag

form, adapted to be fitted, in use, to pass a flow of water, directed

to a storage vessel, therethrough, further characterised in that the

solids separator is effective to hold sludge therein pending

replacement or cleaning, and there is sufficient filter material above a

full water line to the storage vessel to enable flow therethrough 4 without unacceptable impedance and sufficient of the solids separator

to store build up of sludge to enable a useful period of time between

replacement or cleaning. The solids separator may be adapted to be

removably hung, in use, beneath and from a coarse mesh separator,

at an inlet to the storage vessel, suspended inside the storage vessel

to receive water flowed to the inlet. It may be fitted with an outlet

thereto to enable cleaning by flushing through the outlet. It might be

dimensioned with a length greater than the height of the storage

vessel and a substantially uniform diameter there-along. It might

comprise a number of separating bags of increasing separative ability,

nested, in use, one inside the other. The filter material is typically

effective in the separative range 0.5 micron and upwards, preferably

operating in the range 1 micron to 1 .0 millimeter, ideally being 5

microns, or is made of a needle punched polyester felt material. The

solids separator might be fitted with looped straps extending from

and arrayed around its opening, for attachment over or to a feature of

a storage vessel such as a leaf or insect guard to hang, in use, at an

inlet thereto.

The invention includes a storage vessel comprising an

inlet fitted with a solids separator of the above defined kind effective

to hold sludge therein pending replacement or cleaning. The solids

separator might be hung from the inlet to extend down the height of

the storage vessel and to extend, in part, over the bottom of the 5 storage vessel. Alternately, the solids separator might be extended

around and beneath the roof, hung from the roof of the storage

vessel substantially above the full water line of the storage vessel.

The storage vessel might be fitted with a drain from within the solids

separator to the exterior of the storage vessel, with a tap to control

outflow. The storage vessel might be fitted with a flow pipe to direct

water to the storage vessel, the solids separator can be located in the

flow pipe to have inflow to the pipe directed therethrough.

The invention also includes a method of filtering water

flowed to a storage vessel wherein a bag form filter is formed in a

filter material, it is mounted in the flow of water with a substantial

area for filtering located above the full water level of the storage

vessel, it is removed and replaced or cleaned, or flushed, to clear the

bag of sludge. The bag might be removed, flushed, washed and

reinstalled.

DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to

various preferred embodiments which are shown in particular detail in

the accompanying drawings in which:

FIG. 1 shows a sectional view through a storage vessel

with a solids separator in the form of a long, substantially sock-like

element, mounted therein, in accordance with the invention; 6 FIG. 2 shows a sectional detail of a solids separator in

accordance with the invention, formed in this embodiment by a

plurality of nested, substantially bag-like elements;

FIG. 3 shows with sectional detail, the formation of a

solids separator, in accordance with the invention, substantially in

sock form;

FIG. 4 shows a detail of the end of a generally sock-form

or bag-form solids separator in accordance with the invention;

FIGS 5 and 6 show a solids separator in accordance with

the invention hung from the roof of a storage vessel and extended

thereabout closely under the roof;

FIGS. 7 and 8 show details of an adaptation of a solids

separator by which to flush the solids separator whilst it remains in

place inside a storage vessel, in accordance with the invention;

FIG. 9 shows a further form for a solids separator in

accordance with the invention, mounted upstream of a storage

vessel;

FIG. 10 shows a detail revealing a means of fitting a

solids separator in accordance with the invention to a concrete tank

in accordance with the invention;

FIG. 1 1 shows a solids separator in accordance with the

invention adapted to be fitted within a storage vessel via interaction

with a leaf strainer at an inlet to hang there-off inside the storage

vessel; and 7 FIGS. 12 and 13 show details of the support means by

which a solids separator in accordance with the invention might be

hung beneath a leaf strainer in the position shown in FIG. 1 1 .

PREFERRED EMBODIMENTS

In FIG. 1 , a typically five micron, preferably polyester,

needle punched felt material, solids separator, in sock form, which

may be approximately three meters long, is seen in a typical storage

vessel, in this case the usual cylindrical tank. The length of the sock

might be varied. A longer sock has the advantage that there will be a

longer time till the sludge builds up to reduce the area of the sock

available for filtering and the time at which it should be replaced or

cleaned and reused. The material of the solids separator is ideally a

needle punched polyester felt. It will be clear to those skilled in the

art that other materials, such as woven materials, in a range of

material types such as other fabric filaments and fibres, including

natural fibres and materials such as metals may be used in

construction of solids separators in this embodiment, and in each of

the other embodiments described below. It will be apparent to those

skilled in the art that the fineness of the material from which the

solids separator is made will determine the fineness of the material

which will be filtered, and the other dimensions of the solids

separator, its size or area presented to the flow of fluid, will 8 determine the flow volumes which can be handled, the degree of

build up of separated sludge and the time to replacement or cleaning

for reuse. The solids separator may be securely fastened with an

adjustable and/or removable means, such as a clamp, ideally to a

cylindrical projection, typically approximately 150 millimeters

diameter, attached, in this embodiment, on the bottom of a generally

tapered funnel which may additionally house a coarse mesh separator

of the usual kind to filter larger particulate such as insect parts,

leaves and the like, the assembly being positioned at the inlet of a

storage vessel. It will be clear to those skilled in the art that the

assembly may work with additional leaf screens and mechanisms

which dump the first water to flow off a collection surface. The

solids separator, in sock-form in this embodiment, may be hung or

suspended in the vessel to separate and collect the solids from

incoming rain water so as to contain sludge therein and reduce build

up of contaminants inside the storage vessel itself. The solids

separator may be removed and disposed of when clogged or it might

be removed and cleaned and replaced as required. The length is

ideally sufficient that the sludge can sink therein and the diameter and

length above the full water line is ideally chosen to leave an adequate

surface area in play to continue the filter function when the storage

vessel is near full, without there being too great a resistance to flow

that may see water lost to the system by overflow upstream. It will 9 be clear to those skilled in the art that the water flow through the

filter medium is substantially reduced and may be substantially

extinguished below the water level in the tank by the body of stored

water so that effective operation is in the area above the water level.

To this end, the filter material may be in the top zone and the lower

end of the sock might be provided in other materials sufficient to hold

the filtered sludge.

In FIG. 2, the solids separator is made up of a number

of separating socks or bags, ideally, but not necessarily, in cylindrical

form, preferably of increasing separative ability, coarser at the inner

and finer at the outer, which may be fixed to a stepped, conveniently

cylindrical projection, by means of suitable removable and/or

adjustable attachment means, such as clamps, on the bottom of a

preferably and generally tapered funnel which may house a coarse

mesh separator. The solids separator is positioned in this

embodiment at the inlet of a water storage vessel. The bags are then

suspended into the vessel to separate and collect the solids from

incoming fluid to prevent build up inside the vessel. They can be

removed and then cleaned or replaced when required. The inner bag

might be a 5000 micron material and 1500 mm long. The middle bag

might be in a 500 micron material and 1800 mm long. The outer bag

can be in a 1 micron material and 2100 mm long. The progressive

change in separation ability is advantageous in removing larger solids 10 before contact with the finer material, reducing the time to clogging

of the solids separator. It will be clear to those skilled in the art that

the number of the bags used in the solid separators might be varied

to suit a desired outcome. It will also be clear to those skilled in the

art that the material of the bags to the solids separator might be any

of the materials described above including needle punched polyester

felts.

The above solids separator sock, or the bags, may be

made of any type of separating material and sewn or otherwise

manufactured to form a vessel which is open at one end only as will

be clear to those skilled in such arts. The desired separating ability of

the sock or bags is determined by the degree of cleanliness required

in the storage vessel, and the frequency of cleaning or replacement of

the sock or bags. The fineness of the material may typically vary

over the range from substantially 0.1 micron upwards, to typically

around 1 .00 millimeter, with 5 micron providing a generally useful

result.

In FIG. 3 is seen the formation of a long or elongate filter

sock 22 which may be formed by taking an elongate rectangular

piece of suitable material, of any of the kinds described above as are

suited to processing in this particular manner, folding it to join its

longitudinal edges and stitching or otherwise joining them at 24,

joining them together to form an essentially tube-like structure. 11 Subsequently the tube 22 can be stitched or otherwise joined at one

end 25 to close it off and form a sock 23 with open end 26 whereat

fluid may be flowed into the sock. Alternate treatments may be made

to close the end such as by means of adhesives, by heat sealing

plastic based materials, or by tying off the end.

In FIG. 4 is seen a detail at the closed end of a filter sock

27 whereat the material of the sock might be folded over on itself and

clamped between arms 29, 30 of end clamping device 28 which

might be an extrusion in a suitable plastics material. The end clamp

might be designed to enable removal for cleaning and re-application to

re-close the sock for reuse.

In FIGS. 5 and 6 is seen a side elevation and a plan view

of a solids separator 31 mounted beneath the roof 32 of a tank, being

suspended thereunder on hangers 33 to hold it up above the water

level, snaking around from inlet 34. The solids separator might be

supported in a hollow tube which is holed strategically to permit

outflow of fluid. This embodiment is operative to effect a filtering

operation over the length of the solids separator as there is no length

submerged in water to be rendered less operative thereby.

in FIG. 7 is seen a means by which a solids separator

might be flushed. Tank 35 is filled via pipe 36 feeding water, typically

via leaf strainer 37, with solids separator 38 hung therebeneath. The

water level 39 is determined at full capacity by overflow 40. The 12 solids separator 38 is fitted with an outlet passed out of the tank to

outlet 41 controlled by tap or valve 42. Opening valve 42 will allow

water in the solids separator 38 to flow out and carry with it a body

of solids contained therein. This has an advantage in not needing to

de-mount or remove the solids separator for cleaning.

In FIG. 8, the flush outlet is positioned at the bottom of

the solids separator with the advantage that the arrangement is

effective to enable flushing at lower water levels in the tank, or with

greater effectiveness when it is full and the pressure at the outlet is

correspondingly greater to make the outflow faster and more

effectively entrain sludge settled at the bottom of the solids

separator. It will be clear to those skilled in the art that the geometry

of the solids separator might be varied suit the flushing operation as

by surfaces sloped towards the outlet to more effectively entrain

sludge in the flush water.

In FIG. 9 is seen a tank 44 filled from pipe 45 via strainer

46. A solids separator 47 is shown suspended in pipe 45. Filtering

here is effected primarily by the solids separator 47 with the strainer

46 acting to vent the tank and prevent passage of insects. It will be

clear to those skilled in the art that there may be a leaf strainer and

the like up stream so as to catch larger debris before it enters the

solids separator. 13 In FIG. 10 is seen a solids separator 54 hung inside a

concrete tank 48 fed with water via pipe 49 which feeds to elbow 50

mated to a cover 51 which seals to the tank 48 and a downpipe 53.

The solids separator 54 is clamped to the downpipe 53 by clamp 55.

The elbow 50 might not be permanently fixed to the stormwater pipe

49 to enable its removal and removal of the solids separator.

In FIGS. 1 1 to 13 is seen a solids separator 58 hung

beneath a leaf strainer in a tank 56. The solids separator, as

illustrated, is a generally cylindrical bag 58 with hangers 59. It will

be clear to those skilled in the art that the shape of the solids

separator might be varied and shapes such socks or cones might be

adopted. The supports or hangers are seen in FIG. 13 in greater

detail. A strap 60 may have its end 61 attached to the solids

separator 58 by stitching, or the like, and a looped end 62 may be

provided therein to take a cord (not shown) by which to the solids

separator may be tied or attached to or over the strainer 57, typically

the cord is looped through the straps to draw them, and/or the upper

edge of the solids separator, over the top of the leaf strainer. Whilst

four such devices are shown, it will be clear to those in the art that

there may be more or less in number with still useful results. Three

provide an optimum connection at least price. A 5 micron solids

separator, 460 mm diameter and 700 mm deep will pass 800 litres of

water per minute in its unclogged state. A 120mm space from 14 bottom of overflow pipe to the bottom of the leaf strainer might be

provided thus giving a water flow of 1 36 litres per minute which can

enter and leave the tank if it is full. This will reduce the possibility of

water overflowing the strainer when the tank is full of water. A

465mm round hole may be provided in the top of the tank to take a

leaf strainer which also supports the solids separator by way of four

straps, with loops through which a nylon cord can be threaded and

tied.

Cleaning of the solids separator might be carried out by

the owner initially in three months from fitting to tank and as required

after that. Expected life of the polyester, felt type solids separator is

expected to be approximately two years, depending on the

environment in which the tank is found.

When the solids separator requires cleaning, good

results can be obtained with the polyester, felt bases separators by

putting them through a wash cycle in a washing machine. Generally

to keep the integrity of the storage vessel and its fluid at a desirable

state, the solids separator should be replaced when it appears that it

no longer cleans up to an acceptable state when washed.

Claims

15 CLAIMS:

1 . A solids separator

comprising:

a filter material, in bag form;

adapted to be fitted, in use, to pass a flow of fluid,

directed to a storage vessel, therethrough;

characterised in that:

the solids separator is effective to hold sludge therein

pending replacement or cleaning; and

there is sufficient filter material above a full liquid line to

the storage vessel to enable flow therethrough without unacceptable

impedance and sufficient of the solids separator to store build up of

sludge to enable a useful period of time between replacement or

cleaning.

2. A solids separator as claimed in claim 1 adapted to be

removably hung, in use, beneath and from a coarse mesh separator,

at an inlet to the storage vessel, suspended inside the storage vessel

to receive liquid flowed to the inlet.

3. A solids separator as claimed in claim 1 with an outlet

thereto to enable cleaning by flushing through the outlet.

16 4. A solids separator as claimed in claim 1 dimensioned

with a length greater than the height of the storage vessel and a

substantially uniform diameter there-along.

5. A solids separator as claimed in claim 1 comprising a

number of separating bags of increasing separative ability, nested, in

use, one inside the other.

6. A solids separator as claimed in claim 1 wherein the filter

material is typically effective in the separative range 0.5 micron and

upwards, preferably operating in the range 1 micron to 1 .0 millimeter,

ideally being 5 microns, or is made of a needle punched polyester felt

material .

7. A solids separator as claimed in claim 1 fitted with

looped straps extending from and arrayed around its opening, for

attachment over or to a feature of a storage vessel such as a leaf or

insect guard to hang, in use, at an inlet thereto.

8. A storage vessel for a liquid

comprising:

an inlet; and

a solids separator associated with the inlet; 17 characterised in that:

the solids separator is effective to hold sludge therein

pending replacement or cleaning; and

there is sufficient filter material above a full liquid line to

the storage vessel to enable flow therethrough without unacceptable

impedance and sufficient of the solids separator to store build up of

sludge to enable a useful period of time between replacement or

cleaning.

9. A storage vessel as claimed in claim 8, the solids

separator being hung from the inlet to extend down the height of the

storage vessel and to extend, in part, over the bottom of the storage

vessel.

10. A storage vessel as claimed in claim 8, the solids

separator being extended around and beneath the roof, hung from the

roof of the storage vessel substantially above the full liquid line of the

storage vessel.

1 1 . A storage vessel as claimed in claim 8, the storage

vessel being fitted with a drain from within the solids separator to the

exterior of the storage vessel, there being a tap to control outflow.

18 1 2. A storage vessel as claimed in claim 8 with a flow pipe

to direct water to the storage vessel, the solids separator being

located in the flow pipe to have inflow to the pipe directed

therethrough.

1 3 A method of filtering liquid flowed to a storage vessel

comprising;

forming a filter material into bag form;

mounting the bag in the flow of liquid with a substantial

area for filtering located above the full liquid level of the storage

vessel,

removing and replacing or cleaning, or flushing, the bag

of sludge.

14. A method of filtering liquid flowed to a storage vessel as

claimed in claim 1 3 wherein the bag is removed, flushed, washed and

reinstalled.