GB2285591A

GB2285591A - Filtration device for pipe outlet

Info

Publication number: GB2285591A
Application number: GB9400409A
Authority: GB
Inventors: Robert George Firth
Original assignee: DICKENS JOHN CYRIL
Current assignee: DICKENS JOHN CYRIL
Priority date: 1994-01-11
Filing date: 1994-01-11
Publication date: 1995-07-19
Also published as: GB9400409D0

Abstract

The filtration device 2 comprises a hollow cylindrical housing 4 within which is positioned a removable filtration cartridge 6. The device 2 co-operates with an inlet pipe 8 which is arranged to direct fluid to be filtered to a region around the cartridge 6. Filtrate then passes through a filtration membrane of the filtration cartridge 6, as represented by arrows 10, and leaves the device via outlet 12 defined in an outlet housing 13. The filtration cartridge 6 comprises a hollow perforated core 20 (Figure 2) around the outside of which is provided a perforated nylon sleeve 22 (Figure 3). Respective ends of the sleeve are folded back upon themselves and positioned within respective ends of the core. They are secured in position by a respective lower securement member 42 and a lid 60, each of which includes a member (52 and 54, Figures 1 and 4; and 74 and 76, Figures 1 and 5 respectively) which fits within the core and is arranged to clamp the ends of the sleeve in position. A handle 14 is secured to the housing 4 and is arranged to be gripped by one hand of an operator whilst the other hand of the operator may operate a valve (not shown) which is positioned close to, but upstream of, the inlet pipe 8. <IMAGE>

Description

FILTRATION This invention relates to filtration.

In chemical process plants, a valve is generally provided at an outlet end of a fluid pipe for controlling the flow of fluid from the pipe to the outside. The outlet end of the pipe is arranged to be held by an operator and the valve is arranged to be operable by the operator so that fluid may be directed from the pipe to a desired location. The valve at the end of the pipe is often referred to as a "run off gun".

It has long been accepted that, in some instances, it may be desirable to filter fluid flowing from the outlet end of the pipe via the run off gun. One widely used method for filtering such fluid involves securing a perforate filtration bag around the end of the fluid pipe.

Fluid is then filtered by the bag material prior to it passing to the outside.

However, a filtration bag may be a cumbersome and inefficient filter and, additionally, it may be difficult to direct fluid flowing from the bag to a desired location.

It is an object of the present invention to address the above-described problems.

According to a first aspect of the invention, there is provided a device for filtering a fluid adjacent an outlet of a fluid conveying means, the device comprising a housing having a fluid inlet and a fluid outlet, and a filtration means provided in the housing and being arranged to filter fluid flowing between the inlet and the outlet.

The outlet of the device suitably leads to the outside, so that fluid may be directed from the fluid conveying means to a desired location, for example into a tank or other container. The device is preferably for filtering a fluid downstream of a fluid flow control valve. For example, the fluid flow control valve may be a valve of a run-off gun which is suitably provided towards a downstream end of a fluid conveying means, for example a fluid pipe.

Said filtration means is preferably arranged to be releasably secured within the housing. Said filtration means preferably comprises a filtration membrane and a support means arranged to support the filtration membrane.

Said filtration membrane preferably surrounds the support means. Preferably, the filtration membrane is in the form of a sleeve which surrounds the support means. Said sleeve is preferably open at both of its ends. The sleeve is preferably elongate. The sleeve is preferably nonself-supporting. The sleeve is preferably flexible.

Said filtration membrane is suitably of perforate construction. Preferably, the filtration membrane is made of a mesh material. Said mesh material is preferably substantially inert. Said mesh material may comprise a steel mesh or a synthetic polymeric mesh. A preferred mesh material is nylon.

Said support means preferably supports the filtration membrane from within. The support means preferably comprises a core. The filtration membrane, suitably in the form of the aforementioned sleeve, is preferably disposed outside said core. Said filtration membrane preferably surrounds the entire core.

Said support means is preferably of perforate construction. The support means is preferably made of an inert material, for example from a plastics material. The support means may, however, be made of a metal, for example, of stainless steel. The support means may be a wire cage.

A filtration membrane securement means is preferably provided for releasably securing the filtration membrane relative to the support means. Thus, advantageously, said filtration membrane may be disengaged from said support means and replaced should the membrane become clogged or otherwise damaged in use.

Said filtration membrane securement means is preferably arranged to releasably secure the membrane in position relative to the support means at two spaced apart positions. Said two spaced apart positions are preferably at or adjacent respective opposite ends of the membrane.

Said securement means is preferably arranged to releasably clamp the membrane in position. Said securement means may comprise one or two end securement members which are arranged to co-operate with the support means for securing the filtration membrane in position. Where the filtration means comprises a core and sleeve as described above, each end securement member is preferably arranged to fit within, and preferably to be a frictional fit within, a respective end of the core. Preferably, said sleeve is secured in position, at least in part, by being entrapped between an inside surface of the core and a said securement member.

Where the filtration membrane is in the form of a sleeve, and the support means in the form of a core, the sleeve may be preformed and arranged to be a sliding fit on the core. Alternatively, the sleeve may comprise a sheet of material which is wrapped around the core and releasably secured in position, for example by Velcro (Trade Mark) fastening means, to define the sleeve. This latter described type of sleeve may be particularly advantageous since the sleeve may be arranged to be a very tight (non-sliding) fit on the core.

Said housing of the device is preferably cylindrical, more preferably circularly cylindrical.

Said fluid inlet of the device is preferably provided in a lower region of the housing, preferably in a side wall (for example a cylindrical side wall) thereof. Said outlet is preferably provided in a lower region of the housing, preferably in an end wall thereof. Said outlet preferably extends generally in the direction of an elongate axis of the housing. Said axis preferably extends in the direction of an elongate axis of the filtration means.

Said device is preferably arranged to be supported by an operator. A handle means may be provided for use by an operator to support the device. Said handle means is preferably secured to the housing.

According to a second aspect of the present invention, there is provided an assembly comprising a fluid conveying means and a device according to said first aspect for filtering a fluid adjacent an outlet of the fluid conveying means and a control means, for example a control valve, upstream of the device for controlling the passage of fluid through the device.

Said control valve is preferably arranged to be controlled by an operator when the operator is supporting the device.

According to a third aspect of the present invention, there is provided a method of filtering a fluid adjacent an outlet of a fluid conveying means, the method using a device according to said first aspect.

According to a fourth aspect of the invention, there is provided a filtration means for a device according to said first aspect or an assembly according to said second aspect, the filtration means comprising a filtration membrane and a support means arranged to support the filtration membrane.

According to a fifth aspect of the invention, there is provided a filtration membrane for a support means per se.

Specific embodiments of the invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, in which : Figure 1 is a longitudinal cross-section through a filtration device; Figure 2 is a perspective view, partly cut-away, of a core of a filter cartridge; Figure 3 is a side elevation of a filtration sleeve for the filter cartridge of Figure 2; Figure 4 is a side elevation of a lower securement member of the filtration device; Figure 5 is a side elevation, partly in crosssection, of a lid of the device; Figure 6 is a cross-section along line VI-VI of Figure 5; and Figure 7 is a plan view in the direction of arrow VII of Figure 5.

The filtration device 2 shown in Figure 1, comprises a hollow cylindrical housing 4 within which is positioned a removable filtration cartridge 6. The device 2 cooperates with an inlet pipe 8 which is arranged to direct fluid to be filtered to a region around the cartridge 6.

Filtrate then passes through a filtration membrane of the filtration cartridge 6, as represented by arrows 10, and passes to the outside via outlet 12 defined in an outlet housing 13. A handle 14 is secured to the housing 4 and is arranged to be gripped by one hand of an operator whilst the other hand of the operator may operate a valve (not shown) which is positioned close to, but upstream of, the inlet pipe 8.

The device 2 is described in greater detail below.

The filtration cartridge 6 includes a hollow core 20 (Figure 2) around which is provided a perforated sleeve 22 (Figure 3) which sleeve is the filtration membrane of the device.

The core 20 is in the form of an elongate cylinder which is perforated throughout by means of equidistantly spaced openings 24. (It should be noted that in Figure 2 not all openings 24 are shown and that part of an upper part of the core is shown in cut-away form, in the interests of clarity). The core may be made from an inert plastics material. Alternatively, it may be made from stainless steel.

The sleeve 22 is made from perforate nylon material which is flexible and non-self-supporting. A rectangular piece of material may be folded about a central longitudinally extending axis 26 and then opposite longitudinally extending edges 28 may be fixed together by means of two parallel longitudinally extending rows of nylon stitches 30, 32. The end 34, 36 of the material may be hemmed by folding the material inwardly and stitching superimposed parts together by means of two parallel transversely extending rows of nylon stitches 38, 40. The length of the sleeve 22 is slightly greater than that of the core 20.

The lower securement member 42 (Figure 4) of the device includes a cylindrical locating pin 44 at its lower end. The pin 44 is arranged to be snugly received in an upper part of outlet 12. The pin 44 is connected to a cylindrical flange portion 46 which carries O-rings 48, 50 at its upper and lower ends. The flange portion 46 is connected to a cylindrical stopper portion 52, of reduced diameter compared to that of the flange portion 46. The stopper portion 52 carries an O-ring 54. The flange portion 46 and the stopper portion 52 together define a stepped arrangement which is arranged to engage a correspondingly shaped arrangement within a lower part of the housing 4 of the device 2. The stopper portion 52 is arranged to be snugly received in a lower end of the core 20.

The lid 60 (Figures 5 to 7) of the device 2 includes a disc-shaped head part 62 through which four bores 64 extend. The lid 60 further includes a stepped neck part 66. The neck part 66 includes a first cylindrical O-ring support part 68 which carries O-ring 70. A cylindrical flange 72 is attached to a lower part of O-ring support part 68. The diameter of the flange 72 is slightly less than the maximum diameter of the O-ring 70, so that the flange lies wholly within the outline of the O-ring 70.

A stopper portion 74 is attached to the flange 72. The stopper portion carries an O-ring 76. The stopper portion 74 is arranged to be snugly received in an upper end of the core 20.

The handle 14 is secured to the housing 4 by means of a flexible metal strap 80. An adjustment device 82 is provided for adjusting the diameter of the strap 80 so that the handle may be removed from engagement with the housing, if desired.

Four bolt shanks 84 are fixed to and project from an upper wall of the housing. The shanks are arranged to extend through bores 64 in the lid 60.

The device 2 is assembled as follows. The sleeve 22 is positioned around core 20, with ends of the sleeve 22 extending slightly beyond each end of the core. The ends of the sleeve are then folded back upon themselves and pushed into the ends of the core 20. Then, the stopper portion 52 of the lower securement member 42 is pushed into the lower end of the core, so that the lower end of the sleeve 22 is secured in position between the stopper portion 52/0-ring 54 and the inner wall of the core 20.

The core, sleeve and lower securement member assembly are then positioned in the housing 4 such that pin 44 of the lower securement member is received in outlet 12 of the outlet housing 13.

The lid 60 is then engaged with the housing 4 such that bolt shanks 84 extend through bores 64 in the lid and the stopper portion 74 extends into the core so as to secure the upper end of the sleeve 22 in position between the stopper portion 74/0-ring 76 and the inner wall of the core. A nut 88 is then engaged with each bolt shank 84 in order to secure the lid in position.

It should be appreciated that the filtration cartridge 6 is engaged within the housing so that the only path for fluid flowing between inlet pipe 8 and outlet 12 is via the sleeve 22. The sleeve functions to filter the fluid.

When the sleeve becomes clogged or is otherwise damaged, it may be easily removed. In this respect, the filtration cartridge 6 is removed from the housing 4 and the sleeve removed from the core 20. The "old" sleeve may be discarded and a "new" sleeve engaged with the core.

It should be appreciated that the only part of the device 2 that may need replacing is the sleeve 22 - the core 20 and the other parts of the device 2 may be used many times. Thus, the use of cartridge 6 with removable sleeve 22 may provide a relatively cheap method of filtration.

Manufacture of a sleeve for the device 2 may be simplified compared to that of sleeve 22 described above.

For example, instead of using double-sticking to secure edges 28 and ends 34, 36 together, single-sticking may be adequate. In one embodiment where the sleeve is made of nylon material, ends 34, 36 may not be hemmed. In this event, a hot knife may be used to seal the ends 34, 36 to stop the nylon material fraying. Also, as an alternative to stitching longitudinally extending edges 28 together, means may be provided for releasably securing the edges 28 together. For example, a plurality of transversely extending strips of respective Velcro (Trade Mark) elements may be provided at suitable positions along the edge 28. The sleeve may then be wrapped around the core and the respective Velcro elements engaged so that the sleeve may tightly engage the core. The use of Velcro in this manner may allow the sleeve to be a tighter fit on the core in comparison to the case wherein the sleeve is preformed prior to engagement with the core as in the Figure 3 embodiment.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. A device for filtering a fluid adjacent an outlet of a fluid conveying means, the device comprising a housing having a fluid inlet and a fluid outlet, and a filtration means provided in the housing and being arranged to filter fluid flowing between the inlet and the outlet.

2. A device according to Claim 1, wherein the outlet leads to the outside, so that fluid may be directed from the fluid conveying means to a desired location.

3. A device according to Claim 1 or Claim 2, for filtering a fluid downstream of a fluid flow control valve.

4. A device according to any preceding claim, wherein said filtration means is arranged to be releasably secured within the housing.

5. A device according to any preceding claim, wherein said filtration means comprises a filtration membrane and a support means arranged to support the filtration membrane.

6. A device according to Claim 5, wherein the filtration membrane is in the form of a sleeve which surrounds the support means.

7. A device according to Claim 6, wherein the sleeve is flexible.

8. A device according to any of Claims 5 to 7, wherein said support means is of perforate construction.

9. A device according to any of Claims 5 to 8, wherein a filtration membrane securement means is provided for releasably securing the filtration membrane relative to the support means.

10. A device according to Claim 9, wherein said filtration membrane securement means is arranged to releasably secure the membrane in position relative to the support means at two spaced apart positions.

11. A device according to Claim 9 or Claim 10, wherein said securement means comprises one or two end securement members which are arranged to co-operate with the support means for securing the filtration membrane in position.

12. A device according to any of Claims 9 to 11, wherein said filtration means comprises a support means in the form of a core and a filtration membrane in the form of a sleeve and wherein a respective end securement member is arranged to fit within a respective end of the core.

13. A device according to Claim 12, wherein said sleeve is secured in position, at least in part, by being entrapped between an inside surface of the core and a said securement member.

14. A device according to any preceding claim, wherein said fluid inlet is provided in a lower region of the housing.

15. A device according to any preceding claim, wherein said fluid outlet is provided in a lower region of the housing.

16. A device according to any preceding claim, arranged to be supported by an operator.

17. A device according to any preceding claim, including handle means for use by an operator to support the device.

18. A device according to Claim 17, wherein said handle means is secured to the housing.

19. An assembly comprising a fluid conveying means and a device according to any of Claims 1 to 18 for filtering a fluid adjacent an outlet of the fluid conveying means and a control means upstream of the device for controlling the passage of fluid through the device.

20. An assembly according to Claim 19, wherein said control valve is arranged to be controlled by an operator when the operator is supporting the device.

21. A method of filtering a fluid adjacent an outlet of a fluid conveying means, the method using a device according to any of Claims 1 to 18.

22. A filtration means for a device according to any of Claims 1 to 18 or an assembly according to Claim 19 or Claim 20, the filtration means comprising a filtration membrane and a support means arranged to support the filtration membrane.

23. A device for filtering a fluid, an assembly which includes said device, a method of filtering a fluid and a filtration means, each being independently substantially as hereinbefore described with reference to the accompanying diagrammatic drawings.