Field of the invention

This invention relates to an apparatus for removing slurry from a body of fluid such as, for example, flu d from a solvent extraction or eleetrowinn!ng/ electro-refining process.

Background! to. the invention

The accumulation, of solids in solvent extraction and elecirowlnnlrig processes as a settled bottom solids or a an interface of settled solids between the separated / ^' separating organic and aqueous phases is problematic as the solids must be removed in order for the processes: to continue operating effectively.

Various solids removal methods are currently being: used. Such methods - ^' include the use of suction devices- thai use a positive displacement or centrifugal pump system to suck u the solids as a slurry.

A -drawback of thi process Is that the suction effec Is localized and the device must therefore be moved around continuously when covering large areas. In addition, the .use of pumps brings with it the cost of maintaining- same,- which can be. substantial ^" when wo ki g with slurries.

The use of suction devices as described above also brings with It the removal of large amounts of the actual process fluid, which Is not desirable and increases the cost of running the solvent extraction o eiectrowinning/ eiectrorefining processes.

Manual strainers have also been used to remove solids as a slurry from bodies of fluid but this is labour intensive and can be an occupational health risk, and results: in high levels of spillage and losses of process fluid, thereby Increasing process operating costs. The inventor therefore believes, that a need exists for providing an apparatus for collecting and removing solids as a slurry from a bod of fluid which overcomes at least some of the disadvantages of current slurry removal methods as described above.

I Summary of th® Inm tm

According to the Invention, there Is provided an apparatus for removing slurry from a body of fluid, the apparatus including:-

- one or more suction pipes; - one or more compressed gas supply lines that In use deliver compressed _. gas- to an Interior free end region of the suction pipe or pipes; and

- a connector for connecting a hose In fluid flow communication with the one or more suction pipes for in. use permitting discharge of the slurry at a location remote the body of fluid. The apparatus may preferabl Include four suction pipes arranged substantially parallel to each other a:nd which/pipes may terminate in a suction mansfeld arranged In flow communication with foe suction pipes.

It is; to b.¾- appreciated, that other forms of arranging a plurality of suction pipes also: fall within the scope of the present Invention, The suction pipes may, for example, be arranged in a square or circular manner. It Is to be appreciated,, that more of less than four suctio pipes may be provided.

Each suetiQO pipe may have an internal diameter of between 40mm and 100mm and ^: may be between 0.4 m and 1.5 m long.

The compressed gas may be compressed atmospheric air. The compressed gas supply lines may be arranged to run along an outer surface of the suction pipes or may be Incorporated Into an external protective covering which may encase the suction ^' ipes.

Each compressed gas supply line may terminate in a U-bend or elbow which opens Into an Inferior of the suction pipes, thereby directing the compressed air away from free ends of the suction pipes.

The compressed gas supply lines may terminate some length up the pipes away from their free ends. The supply lines typically terminate between 50mm and 300mm Into the suction pipes. i he compressed gas supply lines may lead Into a compressed gas manifold.

The apparatus may further include a connecting pipe for connecting the suction manifold to the hose. Alternatively, the hose may he connected directly to the apparatus via a suitable -connector. The length of th hose may he selectable in accordance with a location of a vessel lor receiving the slurry.

As the dimensions of the individual parts of the apparatus may be varied, the may be selected individually for each slurry removal operation to be carried out

The- individual ^" components making up the apparatus may be manufactured from any suitable, material selected from one or more of: a stainless steel alloy, high density polyethylene, polyvinyl chloride, .polycarbonate, polyfetrafluoroethyiene, nylon, and fibre re-enforced plastic. fp the event that the individual components are manufactured from a metal, they ma be encased by a protective covering: manufactured from a synthetic plastics material. The synthetic plastics material may be high density polyethylene.

The - individual components of the apparatus ma he connected -to- each other by means of conventional couplings or connectors.

One or more vvheels for in use engaging; a floor of body of fluid may be arranged at. free ends of the suction plpe(s). In this mariner, the apparatus may easily be moved along the floor of the body of fluid while at the same time spacing the open IngCs) of the suction plpe(s) away from the floor to allow slurry to enter the suction plpe(s).

In use, the suction pipes may at least partially be submersed IP the body of fluid with free ends of the suction pipes terminating close to the slurry to be removed..

The compressed gas may then be allowed to flow Into the suctio pipes, thereb resulting in a suction force created by all or some of the gas rising along the suctio pipes which in- torn causes the slurry to be sucked into the suction pipes.

The slurry rising up the suction pipes creates a back pressure which In turn results in a portion of the introduced gas to discharge from the free end of the suction pipes, which causes the slurry around the free ends of the suction pipes to he disturbed, in this manner, slurry- located around the suction pipes rather than only that located In close proximity thereto, may .also be removed.

Once slurry in an area has been removed, the apparatus may manually he moved to the next area from which slurry is to he removed or It may- gradually be rolled along the floor of the body of fluid If It Is provided wit wheels.

Detailed Description of the Invention

The invention- will now be described by way of the following, non-limiting exampl with reference to the accompanying drawings. in the drawings:- Figure 1 shows a first embodiment of an apparatus for removing slurry from a bod of fluid In accordance with the present invention;

Figure 2 shows the apparatus of Figure/ 1 along with several connecting pipes;

Figure 3 show's a compressed gas supply system: of the: apparatus of Figure 1:

Figure 4 shows the apparatus of Figur 1 in use; Figure 5 shows a cross-sectioned front view of a second embodiment of an apparatus for removing slurry from a body of fluid in accordance with the present invention: and

Figure 6 shows a: three-dimensional view of the apparatus of Figure 5. in the drawings, reference numeral 10 generally Indicates an embodiment of an apparatus for removing slurr 12 from a body of fluid 14 In accordance with the present invention.

The apparatus 10 shown includes four suction pipes 16 and four compressed air supply lines 18 that in use deliver compressed air to a inferior free end region 20 of the suction pipes 16. A hose 22 Is connected in fluid flow communication with the suction pipes 16 for In use permitting discharge of the slurry 1.2 at a location remote the bod of fluid 14. he suction pipes 18 terminate in a suction manifold 24 arranged in flow communicate wit the suction pipes 16. it is to be appreciated, that other forms of arranging the suction pipes 18 also fail within the scope of the msent Invention. Each suction pipe 16: has an internal diameter of between 40mmar l 100mm and ^' is between 0.4 and 1 ,5 m long.

In the embodiments .shown, in Figures 1 to 5, the compressed air supply lines 18. are arranged to run along an outer surface of the suction pipes 1.8 and terminate in a U- hend as can best foe seen in Figure 3., which opens into an interior of the suction pipes 16. The supply lines 18 typically extend between 50mm and 300mm Into the suction pipes 16.

Figure 3 shows a compressed air supply system: 30 of the apparatus 10. The system 3Q is mounted on the suction pipes 16 and connecting pipe 26 and includes an air supply hose 32 which is in use connected to a source of compressed air (not shown).

The apparatus 10 further includes a connecting pipe ,28 for connecting the manifold 24 to the hose 22.

The length of the hose .22 Is selectable in accordance with a location of a essel for receiving t slurry 12. As the dimensions of th individual parts of the apparatus 10 can be varied, they can be selected Individually far each slurry removal operation to he carried out. So, for example, several connecting, pipes 2M (see Figure 2) can be connected to each other for use of the apparatus: 10 in deep bodies of fluid or a longer connecting pipe 26 as shown in Figure 1 can be used. The Individual components making up the apparatus 10 are manufactured f om: any suitable material selected from one or more of: a stainless steel alloy, high density polyethylene, polyvinyl chloride, polycarbonate, polytetrafluoroethylene, nylon, and fibre re-enforced plastic. The individual components of the apparatus 10 may be connected to each other by means of conventional couplings or connectors 28,

In use, the suction pipes 10 are at least partially submersed in the body of fiuid 14 with free ends of the suction pipes 18 terminating close to the slurry 12 to be removed (see Figure 4),

The compressed air is then .allowed to flow into the suction pipes 16 via the compressed air supply tines 18 , thereb resulting In a suction force created by the a: portion of the gas rising along the suction pipes 16 which in turn causes the. slurry 12 to be sucked info the suction pipes 16, The slurry 12 rising up the suction pipes 16 creates a back pressure which In turn causes a portion of the gas to be discharged from the free ends of the suction pipes and the slurry 12 around the free ends of the suction pipes 18 to be disturbed. I this manner, slurry 12 located around the suction pipes 18 .rather than only that located, in close proximity thereto, is also removed, The slurry 12 travels along the suction pipes 16, connecting pipe 26 and hose 2 and is discharged. Into a vessel or other receiving receptacle (not shown) remote; the body of f luid 14.

Dnce slum/ 12 i an area has been removed, the apparatus ID is manually moved to. the next area from which slurry 12 Is to he removed. Referring now to Figures 5 and ® wherein like parts are denoted by the same reference numbers as in Figures 1 to 4.

The compressed gas supply lines I S are arranged to run along an outer surface of the suction pipes 16 _: where they are Incorporated into an external protective covering 34 which encases the suction pipes 18, Each compressed gas supply ilne18 terminates in an elbow 38 which opens into an Interior of the suction pipes 1 β, thereby directing the compressed air sway from free ends 20 of the suction pipes 16.

As can he seen In Figure 5, the elbows 38 terminate some length up the pipes away from their free ends 20. In the embodiment shown in Figures 5 and 8, the distance between the free ends 20 of the suction pipes 16 and open ends of the elbows 36 is about 300mm.

The Gonipressed gas supply lines 18 lead into a compressed gas manifold 38 at which they are connected to a source of compressed air (not shown). in the embodiment shown, th individual components of the apparatus 10 are manufactured from a metal and are encased by a protective covering 34 manufactured from a high density polyethylene. This inhibits sparking during use of the apparatus.

Two wheels 40 for in use engaging a floor 42 of a body of fluid are arranged at free ends 20 of the suction pipes 16, In this manner, the apparatus 10 can easily be moved along the floor 42 of th body of fluid while at the same time spacing the openings of the suction pipes away from the floor 42 to allow slurry to enter th suction pipes 18. it is to be appreciated, that the Invention Is not limited to any particular embodiment or configuration as hereinbefore generally described .©Hfiustrated