AU2005202701A1 - Flow diversion systems - Google Patents

Description

q FLOW DIVERSION SYSTEMS o This invention relates to flow diversion systems.

ci The invention has particular application to flow diversion systems for use in preventing contaminants and contaminated ci storm water from roads, car parks, building sites and the like from entering, creeks, rivers and other waterways.

Various devices for collecting contaminants or diverting ci ci storm water from its normal course before it reaches storm water drains or water courses, tanks or the like are available.

Some known devices intended to be mounted in storm water inlet boxes divert large solid waste such as plastic bags, bottles, beverage cans etc from the normal path during a first flush period. However, such devices do not remove small particulate contaminants which are allowed to continue on the normal path and eventually can pollute creeks, rivers and even the sea.

Other devices are capable of diverting water having therein small particulate contaminants but such devices also have drawbacks. For example, international patent application No. PCT/AU98/00193 by Zwart describes a drainage pit having diversion apparatus mounted therein for diverting the initial run off to the sewer system and the rest to the storm water drainage system. The apparatus has a pivoting valve member mounted directly below a grated inlet whereby the inflowing water can hit the valve member immediately above the pivot axis and is not particularly suitable large flow rates nor for in line applications.

V 2 o The present invention is aimed at providing a system and ci components for a system which can be effectively used to inhibit various types of contaminants from hard and soft c- surfaces entering waterways.

With the foregoing in view, the invention in one aspect oresides broadly in a flow diverter for water, including: ci oa valve member having an inlet side and an outlet side and ci I being mounted for movement between a diverted flow position in c- which inflowing water is diverted away from the outlet side by the inlet side and a through flow position in which inflowing water flows across the valve member from the inlet side to the outlet side; and means for causing said valve member to move from the diverted flow position to the through flow position after an elapsed period in the diverted flow. position and for causing said valve member to move from the through flow position to the diverted flow position after an elapsed period in the through flow position.

In another aspect the invention resides broadly in flow diversion apparatus for liquids including: a housing having an inlet, a through flow outlet and a diverted flow outlet; a valve member having an inlet side and an outlet side mounted in said housing for movement between a diverted flow position in which inflowing water is diverted away from the outlet side by the inlet side and a through flow position in IckeeO4IO3.wpd Ic) 3 o which inflowing water flows across the valve member from the inlet side to the outlet side, said valve member being normally biased to the diverted flow position; c-i collection means operatively connected to said valve member for collecting a predetermined quantity of liquid oflowing into said housing to thereby overcome the bias and ci o cause said valve member to move to the through flow position; ci and 0 discharge means for discharging liquid from said collection means to cause said valve member to return to the diverted flow position.

In another aspect the invention resides broadly in a pollution control system for water, including flow diversion apparatus as previously described; and a detention tank in liquid communication with the diverted flow outlet for collecting liquid diverted by the flow diversion apparatus when the valve member is in the diverted flow position.

In another aspect the invention resides broadly in a method of controlling pollution including: selecting a site for installation of a pollution control system as previously described; installing the pollution control system at the selected site such that storm water will flow into the inlet of said housing and the through flow outlet of said housing is /cleeOO4103.wpd Ic) 4 o connected to a storm water drain or the like for discharging storm water; installing an overflow in liquid communication with an intermediate level of said detention tank whereby water may only overflow from the intermediate level of said detention otank; and ci ocollecting pollutants from the detention tank after a ci selected period.

0- Suitably, the valve member is normally biased towards the diverted flow position so as to be ready to divert the first flow of water to the diverted flow path rather than allow it to flow to a storm water drain. The term "normally biased" as used herein refers to the circumstance when there has been no inflowing water for a significant period and the valve member has returned to the diverted position.

In a preferred form the valve member is mounted for pivoting up and down movement about a pivot axis and the bias is achieved by mounting the valve member such that its centre of gravity is one side of the pivot axis. In another form, the bias is achieved by adding a weight to one side of the valve member to move the centre of gravity. In such form, it is preferred that the position of the weight be variable so that the valve member can be calibrated to achieve a desired amount of bias.

Preferably, said collection means includes a collection chamber integral with said valve member and in liquid /cleeOO4103. wpd 3 o communication with said inlet while said valve member is in the diverted flow position via a suitable conduit, for example a pipe, which is arranged to deliver a portion of liquid flowing into the housing to the chamber. Suitably, the collection chamber is arranged such that when the quantity of liquid in othe chamber reaches a predetermined amount, the weight of the ci oliquid overcomes the bias and causes the valve member to move ci to the through flow position. In a preferred form, said c- collection chamber is provided on the outlet side of the valve member.

Preferably, the apparatus includes control means for controlling the quantity of water which is diverted or the rate of flow which must be reached or both before the valve member moves to the through flow position. In a preferred form the control means includes an adjustable valve arranged to control the rate of flow of water to the collection chamber thereby controlling the period taken to fill the collection chamber sufficiently to overcome the bias to the diverted flow position. However, in another form, the apparatus includes a pre-diversion chamber arranged to collect at least a portion of the first flush as it enters the housing and the collection chamber is in liquid communication with the pre-diversion chamber. Advantageously, such arrangement ensures that the supply of water to the collection chamber is relatively stable.

In one preferred form, the collection chamber is in liquid communication with the pre-diversion chamber via a conduit /cleeOO4103. wpd tfl 6 o which opens into the pre-diversion chamber at a predetermined ci height which requires a predetermined quantity of water to have entered therein prior to any water flowing to the collection chamber thus providing a separate control of the amount of water diverted to the detention tank. Suitably, a drain is connected to the pre-diversion chamber- and is adapted to drain ci oany water therein continuously so that the chamber empties ci In between flushes. Thus, in another aspect the invention resides c- broadly. in a flow diverter for water, including: a valve member mounted for movement between a through flow position and a diverted flow position and being normally biased to the diverted flow position; control means for causing said valve member to move from the diverted flow position to the through flow position in response to a predetermined rate of flow over an elapsed period and for causing said valve member to move from the through flow position to the diverted flow position after an elapsed period in the through flow position.

In order that the invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings wherein: Fig.la is a schematic plan view of a pollution control system according to the present invention with the valve member of the flow diverter of the system in the diverted flow position ready for in flowing storm water to be diverted; tcleeOO4103.wpd 0 Fig.lb is a schematic sectional elevation of the pollution control system of Fig.la along line Ib-lb; Fig.1c is a schematic sectional end elevation of the C- pollution control system of Fig.la along Ic-lc; Fig.ld is a schematic end elevation of the pollution 0 control system of Fig.la; SFig.2a is a schematic plan view of the pollution control ci l system of Fig.la showing a storm water inflow with the Ci valve member of the flow diverter in the diverted flow position; Fig.2b is a schematic sectional elevation of the pollution control system of Fig.la along line 2b-2b with the same inflowing event shown in Fig.2a; Fig.3a is a schematic plan view of the pollution control system of Fig.la with the valve member in the through flow position; Fig.3b is a schematic sectional elevation of the apparatus of Fig.la showing the same inflowing event as in Fig.3a but with the detention tank of the system overflowing; Fig.4a is a schematic plan view of the pollution control system of Fig.la after the inflow has finished and the detention tank has been substantially emptied leaving a residual amount of polluted water; and Fig.4b is a schematic sectional elevation of the apparatus of Fig.la at the same stage as in Fig.4a; and /lee004103.wpd 0 Fig.5 is a schematic sectional elevation of part of the system of Fig.la showing the valve member and its movement between a diverted flow position and a through flow Ci position; Fig.6a is a schematic plan view of another flow diverter Sfor a pollution control system according to the present Sinvention (without detention tank shown)with the valve V) member of the flow diverter in the diverted flow position eC ready for in flowing storm water to be diverted; Fig.6b is a schematic sectional elevation of the diverter of Fig.6a along line 6b-6b with the valve member of the flow diverter in the diverted flow position; Fig.7 is a schematic sectional elevation of the diverter of Fig.6a along line 6b-6b after some movement of the valve member towards the through flow position; Fig.8 is a schematic sectional elevation of the diverter of Fig.6a along line 6b-6b after further movement of the valve member towards the through flow position; Fig.9 is a schematic sectional elevation of the diverter of Eig.6a along line 6b-6b after substantial movement of the valve member towards the through flow position and just prior to reaching the through flow position; is a schematic sectional elevation of the diverter of Fig.6a along line 6b-6b with the valve member in the through flow position; /clee00403.wpd tn 9 Fig.lla is a schematic plan view of another diverter with a top grate entry rather than an inline entry with the

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valve member of the flow diverter in the diverted flow C position; Fig.llb is a schematic sectional elevation of the diverter of Fig.lla along the equivalent of line 6b- 0 6b; ci oFig.12a is a schematic plan view of still another diverter ci In with both a top grate entry and an inline entry with the 0- valve member of the flow diverter in the diverted flow position; and Fig.12b is a schematic sectional elevation of the diverter of Fig. 12a along the equivalent of line 6b-6b.

The pollution control system 10, illustrated in Fig. la includes a flow diversion apparatus 11 and a detention tank 12.

The flow diversion apparatus is installed below ground level 13 so that it is at a suitable level below the inflowing storm water pipe 14. A riser 16 is installed on top of the diversion apparatus to provide an inspection opening for access and maintenance at ground level. The detention tank is also installed below ground level to provide for inflow of diverted water from the diversion apparatus at a suitable level. A riser 17 similar to that on the diversion apparatus is also mounted on top of the detention tank to provide access for maintenance and collection at ground level.

The flow diversion apparatus includes a housing 21 having a base wall 22 which is substantially rectangular in form and /clee004103. wpd V o four side walls 23a, 23b, 23c and 23d extending generally ci upwards from the base wall. A divider wall 23e extends between opposed side walls 23a and 23c to divide the housing into two c- chambers, an entry chamber 26 and a discharge chamber 27 with an opening through wall 23e being shaped to form a weir 28. The 0entry chamber has a base wall 29 which is spaced above the base ci owall 22, the two spaced apart base walls defining therebetween ci I a diversion passage 31 there between which opens at one end c- below the divider wall to the discharge chamber 27 and at the other end to the detention tank. A flow through outlet plenum box 32 is connected to the housing at the other end of the discharge chamber opposite the diversion passage to provide a flow passage 34 for flow through water which is connected to the downstream storm water drain (not shown). A plurality of spaced apart vertical baffles 33 are provided in the entry chamber for dissipating the velocity energy of the inflowing water. The base wall has a hump 30 therein having inclined side portions 22a and 22b extending across its width to form a bank adapted to prevent water flowing across the base from the inlet to the outlet and vice versa.

A valve member 36 is mounted in the diversion chamber on a horizontal shaft 37 above the hump 30 for pivoting up and down movement between a diverted flow position as shown in Fig.1b and a through flow position as shown in Fig.3b in a see-saw type manner about pivot axis 35. The valve member is generally U-shaped in cross-section having a base 38 and two spaced apart /cleeO04103.wpd 11 o sidewalls 39 and 40, the base being formed by two contiguous base portions 38a and 38b diverging downwardly away from the pivot axis and forming an inlet part and an outlet part respectively and the base and sidewalls together forming a chute which is adapted to direct inflowing water to the odiversion passage or the plenum box and through passage as the ci ocase may be depending whether the valve member is in the ci Vdiverted flow position or the through flow position.

0- The valve member is biased to the diverted flow position by having its center of gravity on the diversion passage side of the pivot axis. A pair of counter weights 42 is mounted on the valve member and the position of the center of gravity can be adjusted by movement of the counter weights towards and away from the vertical plane containing the pivot axis.

A collection chamber 43 is formed integrally with the valve member, the collection chamber being defined by the base and the two sidewalls at the plenum box end of the valve member and an end wall 44 which extends across the base from sidewall to sidewall and which defines a weir 45 at its upper edge as can be more clearly seen in Fig. A control pipe 46 extends across the valve member, opening at one end 47 in the entry chamber 26 and at the other end in the collection chamber while the valve member is in the diverted flow position and provides a passage for flow of storm water to the collection chamber to control the bias of the valve member. The control pipe is supported by a rod 53 (as can /cleeOO4103.wpd 1 2 o be seen in Fig. 5) which is secured to a side wall of the valve member by a mounting bracket 54 at one end and connected to the pipe at the other end. The rod is extensible in the manner of a A turn buckle and is arranged to adjust the height of the downstream end of the control pipe for adjusting the rate of oflow therethrough and hence the period in which the valve ci omember remains in the diverted flow position and therefore the ci V' quantity of water, which is diverted to the detention tank.

A discharge pipe 51 communicates with the collection chamber and the discharge chamber and is arranged to discharge water collected in the collection chamber to the discharge chamber and thus the plenum box when the water in the collection chamber reaches a predetermined level. The discharge pipe is arranged to continually siphon water from the collection chamber once it reaches the predetermined level so that when water ceases to flow into the collection chamber the water therein will.gradually discharge via the discharge pipe.

In use, storm water enters the entry chamber and collects therein until it reaches the height of the weir 28 whereupon it overflows the weir and flows onto the valve member at base portion 38a which diverts it to the diversion passage 31 while the valve member is in the diverted flow position. Diverted water flows into the detention tank 12 and eventually the detention tank overflows through the overflow 52 if the control pipe is adjusted to a low enough flow. However, while water is being diverted through the diversion passage, a small amount is /clee004103 wpd tl13 o also flowing through the control pipe into the collection chamber in the valve member and if the control pipe is adjusted to allow a high flow rate therethrough, the diverter valve will -q only divert a small amount of water for collection so that a number of storm events may be required to fill the detention otank.

ci SWhen water in the collection chamber reaches a ci I predetermined level, the center of gravity of the valve member c-i moves from the diversion passage side of the pivot axis to the flow through side and the valve member pivots about the axis into the through flow position as can be seen in Fig.3b. Water continuing to enter the discharge chamber via weir 28 then flows across the valve member in the through flow position then over the weir 45 and then into the plenum box and then through the down stream storm water drain, creek or other suitable water way.

The diverter 111 illustrated in Fig. 6a is similar to that of Fig. 1 in many respects and also operates in a similar manner in many respects and consequently the same reference numbers are used to reference corresponding parts where possible except prefaced by a and parts numbered accordingly in the drawings but not specifically referred to herein are to be taken to correspond unless clearly not appropriate.

Instead of having an entry chamber 26 with baffles, diverter 111 has an entry plenum box 161, the outlet 161b of /cleeO04103. wpd I 14 o which is selected to direct inflowing water into a fixed chute 162 adapted to direct water across the width of the housing 121 and onto the inlet part 138a of the valve member 136 without a significant reduction in flow velocity whereby entrained solids remain suspended in the water for diversion through diverted 0water inlet 163a of diverted water plenum box 163 which is used ci oto maintain outlet flow velocity of diverted water. Through ci Iflow water is directed through an outlet plenum 164 although its importance is less important in view of the first flush of water having diverted entrained solid materials to the diverted water outlet. As can be seen the bottom side 162a and lower front side 162b of the fixed chute are open while opposite front and rear sides 162b and 162d are closed for directing inflowing water down for diversion or across for through flow depending on the position of the valve member as will become clearer later. Also, upper base wall 162e has a plurality of openings or water outlets 167 therein for feeding at least a portion of inflowing water to a pre-diversion chamber 168 located therebelow.

Additionally, a movable chute 166 is pivotally mounted to the front wall 162c of the fixed chute for pivoting about axis 169 and extends fully across the housing, the movable chute being adapted to assist in guiding inflowing water to the diverted water outlet or the through flow outlet depending on the position of the valve member. Whereas the control pipe of the first diverter receives water directly from the stream of /cee004103.wpd o inflowing water, the control pipe 146 of diverter 111 receives 0 water from the pre diversion chamber thus ensuring that the flow through the control pipe comes from a stable source.

-K In use of the second diverter, storm water flows through the inlet plenum 161 over the outlets 167 so that a portion of oinflowing water enters the pre-diversion chamber while the rest ci oflows through fixed chute 162 which directs it down onto the ci entry part of the valve member or against the front wall 166c 0 c- of the movable chute which in turn directs it down onto the inlet part of the valve member. The size and shape of the inlet plenum, fixed chute and movable chute are selected to maintain a flow velocity sufficient to maintain solids contained in the inflowing water in suspension so that they are transported with the first flush through the diverted water plenum to the detention tank as with the pollution control system shown in Fig. 1. While the first flush is being diverted a small amount of water is collecting in the pre-diversion chamber and eventually reaches a height at which it starts to flow through the control pipe to the collection chamber 143 formed at the outlet end of the valve member by base wall 143a and front wall 143b.

As the quantity of water in the collection chamber increases, its centre of gravity moves and the valve member starts to rotate about pivot axis 137. Rotation of the valve member causes the movable chute to pivot upwards about its pivot axis 169 to allow the fixed chute to direct inflowing /clee004103.wpd o water across the inlet side of the valve member to the outlet side as it reaches the through flow position and then onto the outlet plenum 164 to a stormwater drain, channel or creek.

i Movement of the centre of gravity of the valve member is also assisted by a plurality of spherical weights housed in the outlet side of the valve member and adapted to move towards the ci otowards the throughflow outlet once the valve member reaches a ci predetermined position of rotation.

ci The diverter 211 shown in Figs. 11a and llb is the same as that of Fig. 6a except that it includes a grated inlet box 271 having an outlet 272 which discharges vertically onto the inlet side of the valve member 236 and consequently the fixed chute 162 and movable chute 166 are not required. However, in other respects it operates in the same manner as the diverter shown in Fig. 6a.

The diverter 311 shown in Figs. 12a and 12b is adapted for receiving in line flow and grated vertical flow and thus combines aspects of both diverter 111 and 211 and generally operates in the same manner as diverter 111.

It will be seen that the pollution control system of the present invention can be used to divert the first flush of storm water from car parks, roadways and the like to a detention tank from where it can be collected by a tanker and discharged into a sewerage system. Alternatively, the overflow 52 can be directly connected to the sewerage system in some applications so that the contaminated water in the tank can be /clee004103. wpd O treated at the sewerage treatment plant. It will also be seen that a large percentage of the water in the detention tank can be used for irrigation or toilet flushing once the contaminants therein have been allowed to settle out and only the residual contaminated water need be collected and treated. Further, if odesired, the system can be used without a detention tank in ci owhich case the diversion passage is connected directly to the ci sewerage system.

0- While the foregoing description has been given by way of illustrative example of the invention, it will be understood that the invention may be embodied in other forms and all such forms are deemed to fall within the broad scope and ambit of the invention as defined in the appended claims.

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Claims (12)

1. A flow diverter for water, including: a valve member having an inlet side and an outlet side and being mounted for movement between a diverted flow position in 0which inflowing water is diverted away from the outlet side by ci othe inlet side and a through flow position in which inflowing ci water flows across the valve member from the inlet side to the c- outlet side; and means for causing said valve member to move from the diverted flow position to the through flow position after an elapsed period in the diverted flow position and for causing said valve member to move from the through flow position to the diverted flow position after an elapsed period in the through flow position.

2. Flow diversion apparatus for liquids including: a housing having an inlet, a through flow outlet and a diverted flow outlet; a valve member having an inlet side and an outlet side mounted in said housing for movement between a diverted flow position in which inflowing water is diverted away from the outlet side by the inlet side and a through flow position in which inflowing water flows across the valve member from the inlet side to the outlet side, said valve member being normally biased to the diverted flow position; /cleeOO4103.wpd o collection means operatively connected to said valve member for collecting a predetermined quantity of liquid flowing into said housing to thereby overcome the bias and c- cause said valve member to move to the through flow position; and Sdischarge means for discharging liquid from said ci o collection means to cause said valve member to return to the ci diverted flow position. ci

3. Flow diversion apparatus according to Claim 2, wherein said valve member is normally biased towards the diverted flow position.

4. Flow diversion apparatus according to Claim 3, wherein the valve member is mounted for pivoting up and down movement about a pivot axis and the bias is achieved by mounting the valve member such that its centre of gravity is on one side of the pivot axis.

5. Flow diversion apparatus according to Claim 3, wherein the bias is achieved by adding a weight to the inlet side of the valve member.

6. Flow diversion apparatus according to Claim 5, wherein the position of the weight is variable to change the amount of bias. /cleeOO4103.wpd o 7. Flow diversion apparatus according to any one of Claims 2 to 6, wherein said collection means includes a collection chamber integral with said valve member. ci S8. Flow diversion apparatus according to Claim 7, wherein osaid collection chamber is in liquid communication with said ci o inlet while said valve member is in the diverted flow position. ci c- 9. Flow diversion apparatus according to Claim 8, including control means for controlling movement of said valve member from the diverted flow position to the through flow position. Flow diversion apparatus according to Claim 9, wherein said control means controls the rate of flow from said inlet to said collection chamber while said valve member is in the diverted flow position.

11. Flow diversion apparatus according to Claim 10, wherein said control means includes an adjustable valve arranged to control the rate of flow of water to said collection chamber.

12. Flow diversion apparatus according to Claim 9, wherein said control means controls the time of commencement of flow of water to the collection chamber. /cIlee004103. wpd o 13. Flow diversion apparatus according to Claim 12, wherein said control means includes a pre-diversion chamber arranged to collect at least a portion of the first flush as it enters the (q housing and wherein said collection chamber is in liquid communication with said pre-diversion chamber. ci o 14. Flow diversion apparatus according to Claim 12, wherein ci V said collection chamber is in liquid communication with said iq pre-diversion chamber via a conduit which opens into said pre- diversion chamber at a predetermined height which requires a predetermined quantity of water to have entered therein prior to any water flowing to the collection chamber. Flow diversion apparatus according to Claim 14, wherein a drain is connected to said pre-diversion chamber and is adapted to drain any water therein continuously during inflow.

16. A pollution control system for water, including flow diversion apparatus according to any one of Claims 2 to 15, and a detention tank in liquid communication with the diverted flow outlet of the flow diversion apparatus for collecting liquid diverted thereby when the valve member is in the diverted flow position.

17. A flow diverter for water, including: /cIeeO04103. wpd t22 o a valve member mounted for movement between a through flow position and a diverted flow position and being normally biased to the diverted flow position; c- control means for causing said valve member to move from the diverted flow position to the through flow position in 0response to a predetermined rate of flow over an elapsed period oand for causing said valve member to move from the through flow I position to the diverted flow position after an elapsed period in the through flow position.

18. A method of controlling pollution including: selecting a site for installation of a pollution control system according to Claim 16; installing the pollution control system at the selected site such that storm water will flow into the inlet of said housing and such that the through flow outlet of said housing is connected to a storm water drain or the like for discharging storm water; installing an overflow in liquid communication with an intermediate level of the detention tank of the pollution control system whereby water may only overflow from the intermediate level of said detention tank; and collecting pollutants from the detention tank after a selected period. /cleeOO4103wpd in 23 O 19. The method of Claim 18, wherein said overflow is a syphon 0 having an inlet a predetermined distance above the base of the detention tank. ci

20. Flow diversion apparatus as hereinbefore described with o reference to any of the accompanying drawings. ci ci l y n Dated this 21st day of June 2005 0 0- KEITH LEES By his Patent Attorneys AHEARN FOX /clee004103. wpd