Field of the Invention This invention relates to a slurry processing apparatus, and in particular to a slurry processing apparatus wherein components are more easily maintained, replaced and/or repaired where necessary.

Background of the invention

Slurry processing apparatus are well known devices which are utilised generally to at least partially separate the fluid portion of slurry from the solid portion thereof. Devices of varying types may be employed for this purpose, however one common type of device used is a rotating cylinder type device comprising a cylindrical filter which is rotated between a plurality of rollers. The slurry is passed through the device such that the solid portions of slurry are forced onto an outer surface of the filter and scraped off by a scraper, the liquid portion of the slurry is then carried by a liquid tray from the machine. These devices are effective in separating slurry such that both the solid and liquid portions may be recycled for other agricultural uses. Typically, the filters of these rotating cylindrical type devices experience wear or clogging such that a replacement or repaired filter is required. Current devices of this type are such that filter replacement involves the removal of multiple components, including rollers, and generally takes approximately 4-5 hours. This results in a significant amount of labour and machine downtime. In addition, the liquid tray and other components within the filer body can be difficult to access without significant dismantling of portions of the device. Resultantly, these portions are time consuming to maintain, repair, or replace when required.

It is the object of the present invention to provide a slurry processing apparatus wherein components of the apparatus may be maintained, repaired, and/or replaced with reduced effort and in a reduced amount of time.

Summary of the invention

According to the invention there is provided a slurry processing apparatus comprising a filter; one or more lower roller configured to engage the filter at least during operation to support and/or locate the filter, the one or more lower roller being supportable at or about first and second ends by first and second supports respectively in an operational position; and a retaining means for releasably retaining the at least one lower roller in the operational position upon removal of one of the first or second supports to permit removal, replacement, or maintenance of the filter. Advantageously, the filter may be replaced without removal or any such manipulation of the one or more lower roller, and a new filter may be installed. This vastly reduces the time taken to replace a filter on slurry processing apparatus such as that described by the present invention.

Ideally, the filter comprises a tubular filter having a hollow inner portion and first and second open ends.

Preferably, the at least one lower roller is configured to engage the filter during operation to urge at least a portion of the slurry therethrough.

Preferably, the at least one lower roller extends in an axial direction through the hollow inner portion of the filter.

Ideally, the at least one lower roller is of a length such that the first and second ends of the at least one lower roller protrude from the first and second open ends of the filter respectively.

Preferably, the retaining means is locatable such that it may engage the at least one roller at the first end thereof.

Ideally, upon engagement of the retaining means, the at least one lower roller is retained in the operational position upon removal of the second support.

Ideally, the retaining means releasably retains the at least one lower roller at or about the first end thereof forming a cantilever arrangement when the second support is removed.

Preferably, the retaining means is configured to retain a central shaft of the at least one lower roller.

Ideally, the retaining means comprises an upper retaining member configured to receive an engagement portion of the at least one lower roller.

Preferably, the upper retaining member comprises at least one receiving feature for receiving the engagement portion of the at least one lower roller.

Preferably, the upper retaining member is releasably fixable to a supporting frame of the apparatus.

Ideally, when the engagement portion of the at least one roller is locatable in the at least one receiving feature of the upper retaining member, fixing of the upper retaining member to the supporting frame retains the engagement portion of the at least one lower roller between the supporting frame and the upper retaining member. Ideally, upwards movement of the engagement portion of the at least one roller is prevented when the engagement portion of the at least one roller is locatable in the at least one receiving feature of the upper retaining member and the upper retaining member is fixed to the supporting frame.

Advantageously, unwanted movement of the at least one lower roller is prevented even when the second support thereof is removed.

Preferably, the upper retaining portion is fixable to the supporting frame via a bolt or similar mechanical fixing.

Alternatively, the retaining means may take the form of any generally known clamp type apparatus capable of clamping or retaining a portion of the at least one lower roller at the first end thereof such that the at least one lower roller remains in the operational position even when the second support is removed.

Further alternatively, the retaining means is an elongate member which extends axially internal of the at lest one roller such that the at least one lower roller remains in the operational position even when the second support is removed.

Further alternatively, the first support may form the retaining means.

Preferably, the second support is a movable support such that it can be removed from contact with the at least one lower roller or a component thereof to permit subsequent removal of the filter from the at least one lower roller.

Ideally, the second support is locatable on, or forms part of, a gate or hatch such that opening of the gate or hatch removes the second support from a supporting position, wherein it supports the second end of the at least one lower roller, to a non-supporting position, wherein it no longer supports the second end of the at least one lower roller.

Preferably, in the non-supporting position, the location of the second support permits removal of the filter from the at least one lower roller by passage of the filter over the second end of the at least one lower roller.

Ideally, the at least one lower roller is configured to permit axial rotation of the filter whilst supporting the filter in the operational position.

Preferably, the at least one lower roller is configured to engage an inner surface of the filter, the at least one lower roller being encouraged to rotate by the rotation of the filter. Ideally, an outer surface of the at least one lower roller is configured to engage an inner surface of the filter, the at least one lower roller being encouraged to rotate by the rotation of the filter.

Ideally, the force of engagement between the at least one lower roller and the filter ensures rotation of the at least one lower roller by the filter.

Preferably, there are two lower rollers.

Ideally, in the operational position, the two lower rollers are arranged to extend generally parallel to the axis of rotation of the filter.

Preferably, in the operational position, the two lower rollers are locatable on the inner surface of the filter equidistant either side of an uppermost portion of the inner surface of the filter.

Ideally, the filter is a cylindrical filter.

Preferably, the first support is locatable on a supporting frame of the slurry processing apparatus.

Ideally, the one or more lower rollers comprise bearings or other such suitable rotatable

engagements for rotatable engagement between the one or more lower roller and the supports thereof.

Preferably, the slurry processing apparatus comprises a liquid tray formed for receiving a liquid portion of the slurry.

Ideally, the liquid tray is locatable within the hollow inner portion of the filter.

Preferably, first and second liquid tray supports are configured to support the liquid tray at first and second ends thereof in an operational position.

Ideally, the liquid tray has first and second ends which extend from the first and second open ends of the filter to engage with the first and second liquid tray supports respectively.

Ideally, the liquid tray comprises a sloped surface configured to encourage run-off of the liquid portion of the slurry from the apparatus.

Preferably, the first liquid tray support is a fixed support and the second liquid tray support is a movable support.

Ideally, the second liquid tray support may be moved such that the liquid tray can be removed from the inner hollow portion of the filter means. Preferably, the second liquid tray support is locatable on the gate or hatch.

Ideally, the second liquid tray support is a flange or bracket locatable on the gate or hatch such that the second end of the liquid tray is supportable by the flange or bracket when the gate or hatch is closed.

Ideally, the liquid tray comprises a lip formation configured to engage with the flange of the gate or hatch.

Preferably, the lip formation rests upon the flange such that the liquid tray is supported by the flange.

Preferably, a liquid tray retaining means is locatable proximal the first end of the liquid tray and is configured to retain the liquid tray in the operational position when the second liquid tray support is removed.

Ideally, the liquid tray retaining means comprises one or more mechanical fixings which releasably secure the first end of the liquid tray to a fixed side portion of the slurry processing apparatus.

Preferably, the mechanical fixings are bolts or other such suitable mechanical fixings.

Ideally, the liquid tray retaining means retains the liquid tray at the first end thereof forming a cantilever arrangement when the second liquid tray support is removed.

Alternatively, the liquid tray retaining means is a clamp configured to releasably clamp the liquid tray at or about the first end thereof.

Alternatively, the retaining means of the at least one lower roller and the liquid tray retaining means comprise a single retaining means capable of retaining both the at least one lower roller and the liquid tray.

According to a second aspect of the invention there is provided a slurry processing apparatus comprising a filter drive arrangement in operable engagement with a filter and configured to drive axial rotation of the filter, the apparatus further comprising actuation means for selectably engaging and disengaging the filter drive apparatus from the filter between an engaged and a disengaged configuration such that the filter may be removed, replaced, or have maintenance carried out thereon in the disengaged configuration.

Ideally, the actuation means comprises one or more hydraulic actuation devices. Preferably, the hydraulic actuation means is at least one, but preferably two, double acting hydraulic cylinders.

Ideally, the filter drive arrangement comprises a biasing arrangement configured to bias at least a portion of the filter drive arrangement into contact with the filter when the filter drive arrangement is in the engaged configuration.

Preferably, the biasing arrangement comprises a plurality of springs.

Ideally, the force applied by the actuation means is sufficient to overcome a biasing force exerted by the biasing arrangement in order to engage the filter drive arrangement with the filter in the engaged configuration.

Preferably, filter drive arrangement comprises a motor in operable engagement with at least one drive roller, the drive roller being configured to roll along an outer surface of the filter in the engaged configuration, driving rotation thereof.

Ideally, the motor is in operable engagement with the at least one drive roller via a cog and chain arrangement.

Preferably, the filter comprises two circumferential flanges extending from the outer surface thereof in a generally radial direction.

Ideally, the circumferential flanges are formed for engagement with two end faces of the at least one drive roller.

Preferably, the biasing force applied is sufficient such that, in the engaged configuration, rotation of the at least one drive roller causes rotation of the filter.

Ideally, there are two drive rollers.

Preferably, the two drive rollers extend generally parallel to an axis of rotation of the filter and are locatable on the outer surface of the filter equidistant either side of an uppermost portion of the outer surface of the filter in the engaged condition.

Ideally the double acting hydraulic struts are in operable engagement between the filter drive arrangement and a portion of a supporting frame of the apparatus.

Preferably, the filter drive arrangement is a hinged arrangement configured to rotate, about a hinged connection, into engagement with the filter. According to a third aspect of the invention there is provided a slurry processing apparatus comprising a filter drive apparatus in operable engagement with a filter and configured to drive axial rotation of the filter, the apparatus further comprising actuation means for selectably engaging and disengaging the filter drive apparatus from the filter between an engaged and a disengaged configuration such that the filter may be removed, replaced, or have maintenance carried out thereon in the disengaged configuration, one or more lower roller configured to engage the filter at least during operation to support and/or locate the filter, the one or more lower roller being supportable at first and second ends by first and second supports respectively in an operational position; and a retaining means for selectably retaining at least one lower roller such that the at least lower roller is retained in the operational position after removal of one of the first or second supports to permit removal, replacement, or maintenance of the filter means.

According to a fourth aspect of the invention there is provided a method of removing a filter in a slurry processing apparatus comprising the steps of raising at least a portion of an upper section of the apparatus such that filter drive rollers become disengaged from the filter, retaining at least one lower roller at a first end, opening a gate or hatch such that a support for a second end of the at least one lower roller located on the gate or hatch is removed, passing the filter over the second end of the at least one lower roller, and removing the filter from the slurry processing apparatus.

Ideally, the at least a portion of the upper section of the apparatus is raised hydraulically such that filter drive rollers become disengaged from the filter.

Preferably, the method further comprising the step of passing a replacement filter over the second end of the at least one lower roller, towards the first end thereof.

Ideally, the method further comprising the step of locating the replacement filter such that two circumferential flanges extending from the outer surface thereof engage with two end faces of the drive rollers.

Preferably, the method further comprising the step of closing the gate or hatch such that the second support supports the second end of the at least one lower roller.

According to a fifth aspect of the invention there is provided a removable filter for a slurry processing apparatus comprising an open ended cylindrical body defining inner and outer cylindrical surfaces; and at least one drive roller engagement portion locatable on the outer surface of the filter.

Preferably, the at least one drive roller engagement portion comprises at least one circumferential flange extending from the outer surface of the filter.

Ideally, the at least one circumferential flange extends in a generally radial direction. Preferably, the filter comprises two circumferential flanges extending from the outer surface thereof in a generally radial direction

Ideally, the filter comprises toe circumferential flanges extending from the outer surface thereof, one circumferential flange extending from the outer surface proximal each open end of the filter.

Ideally, the circumferential flanges are formed for engagement with two end faces of at least one drive roller of a slurry processing apparatus.

Advantageously, the two circumferential flanges aid in locating the filter within the slurry processing apparatus and maintaining the location of the filter during rotation of the filter by the at least one drive roller of the slurry processing apparatus.

According to a sixth aspect of the invention there is provided a retaining means for a slurry processing apparatus, the retaining means being configured to selectably retain at least one lower roller of the slurry processing apparatus such that the at least one retained lower roller is retained in an operational position after removal of one of a first or second support of the lower roller to permit removal, replacement, or maintenance of a filter.

Preferably, the at least one lower roller retaining means comprises an upper retaining member operably coupleable to a supporting frame of the slurry processing apparatus.

Ideally, the at least one lower roller retaining means comprises at least one receiving feature for receiving at least a portion of the at least one lower roller.

Preferably, the upper retaining member is operably coupleable by a bolt to the supporting frame of the slurry processing apparatus.

Ideally, rotation of the bolt in a first direction causes the upper retaining member to move towards the frame of the slurry processing apparatus such that the at least one lower roller may be retained therebetween, rotation of the bolt in in second direction acting to release the at least one lower roller.

Brief description of the drawings

Figure 1 is a left side view of a slurry processing apparatus embodying the invention;

Figure 2 is a right side view of a slurry processing apparatus embodying the invention;

Figure 3 is a right side view of a slurry processing apparatus embodying the invention showing a liquid tray; Figure 4 is a top view of a slurry processing apparatus embodying the invention;

Figure 5 is a perspective view of a slurry processing apparatus embodying the invention showing the filter means partially removed thereform;

Figure 6 is a side view of a filter for a slurry processing apparatus;

Figure 7 is an end view of a filter for a slurry processing apparatus;

Figure 8 is a detail view of detail A of figure 6;

Figure 9 is a perspective view of a filter for a slurry processing apparatus;

Figure 10 is a perspective view of a slurry processing apparatus according to the invention showing retaining fixture for rollers;

Figure 1 1 is a perspective view of a slurry processing apparatus according to the invention showing a liquid tray located within the slurry processing apparatus; and

Figure 12 is a perspective view of a liquid tray for a slurry processing apparatus.

Detailed Description of the drawings

The present teaching will now be described with reference to an exemplary slurry processing apparatus. It will be understood that the exemplary slurry processing apparatus is provided to assist in an understanding of the present teaching and are not to be construed as limiting in any fashion. Furthermore, elements or components that are described with reference to any one Figure may be interchanged with those of other Figures or other equivalent elements without departing from the spirit of the present teaching.

Referring now to the accompanying drawings, there is illustrated a slurry processing apparatus 10 having a filter 1 1 and a set of lower rollers 12 which engage the filter 1 1 during operation to both support and locate the filter 1 1 and to urge at least a portion of the slurry therethrough. In typical embodiments, the set of rollers comprises first and second rollers 12, however embodiments having a single roller 12 or more than two rollers 12 would be within the scope of the invention. At least a portion of the solid slurry is urged through the filter 1 1 by the lower rollers 12 onto an outer surface 33 of the filter. As the filter rotates, the solid portion of slurry on the outer surface 33 thereof encounters a scraper 50 which acts to scrape the solid portion of slurry off the filter 1 1 and transport it from the apparatus 10 via a chute 51. The set of lower rollers 12 are supported at first and second ends 13, 14 by first and second supports 15, 16 respectively in an operational position. A retaining fixture 17 is secured at or about the first ends 13 of the lower rollers 12 such that the lower rollers 12 are retained in the operational position (as shown for example in Fig 5) after removal of the second supports 16 to permit removal, replacement, or maintenance of the filter 1 1. The filer 1 1 may then be replaced without removal or any such manipulation of the lower rollers 12, and a new filer 1 1 may be installed. This vastly reduces the time taken to replace a filer 1 1 on the slurry processing apparatus 10. In contrast, prior art devices provide no retention of the lower rollers thereof and as such, once one support of the lower rollers is removed, the lower rollers will fall along with the filter. These prior art devices therefore require removal and re-installation of the lower rollers, and the liquid tray, as part of the filter replacement process. The retaining fixture 17 is tightened and loosened via rotation of a bolt thereof. The fixture 17 comprises an upper retaining member 60 having receiving features 61 formed therein for receiving the first ends 13 of the lower rollers 12. The receiving features 61 comprise two generally u-shaped formations 61 formed in the upper retaining member 60. The upper retaining member 60 comprises a bore 62 formed therein for receiving the bolt, the bolt extending through a portion of the supporting frame 63 of the apparatus 10 such that tightening of the bolt acts to secure the upper retaining member 60 to the supporting frame. Therefore, when the first ends 13 of the lower rollers 12 are located within the receiving features 61 of the upper retaining member, tightening of the bolt secures the upper retaining member to the supporting frame and resultantly prevents unwanted movement of the first end 13 of the lower rollers 12, in particular when the second supports 16 are removed from the lower rollers 12, this can be best viewed in Fig. 1 1. This results in the lower rollers being supported in the operational position by the upper retaining member even when the second supports 16 are removed. As best seen in figures 6 to 9, the filter 1 1 is a generally cylindrical filter 1 1 having a hollow inner portion 18 and first and second open ends 19, 20. The lower rollers 12 extend in an axial direction through the hollow inner portion 18 of the filter 1 1 and are of a length such that the first and second ends 13, 14 of the lower rollers 12 protrude from the first and second open ends 19, 20 of the filter 1 1 . The retaining fixture 17 is located proximal the first support 13 and upon engagement of the retaining fixture 17, the lower rollers are retained in the operational position even should the second support 16 be removed. The retaining fixture 17 retains the lower rollers 12 at or about the first ends 13 thereof forming a cantilever arrangement when the second support 16 is removed. In the embodiment shown in the drawings, the retaining fixture is configured to retain a central shaft 21 of the lower rollers 12. In an alternative embodiment, the first supports 15 may be adapted such that they can preform a clamping operation, effectively preforming the function of the retaining fixture 17.

The second supports 16 are movable supports such that they can be removed from contact with the lower rollers 12 or a component thereof to permit subsequent removal of the filter 1 1 from the lower rollers 12. The second supports 16 are locatable on, or form part of, a gate or hatch 22 such that opening of the gate or hatch 22 removes the second supports 16 from a supporting position, wherein they support the second ends 14 of the lower rollers 12, to a non-supporting position, wherein they no longer support the second end 14 of the lower rollers 12. As can be seen in Fig. 5, in the nonsupporting position, the location of the second supports 16 permit removal of the filter 1 1 from the lower rollers 12 by passage of the filter 1 1 over the second end 14 of the lower rollers. The gate or hatch 22, is a hinged gate or hatch 22 having a hinge 24 connecting it to a lower supporting frame 25 of the apparatus 10. The first supports 15 are also located on the lower supporting frame 25. The lower rollers 12 permit axial rotation of the filter 1 1 whilst supporting the filter 1 1 in the operational position. The lower rollers 12 engage an inner surface 23 of the filter 1 1 such that the lower rollers 12 are encouraged to rotate by the rotation of the filter 1 1 . The outer surface 26 of the lower rollers 12 is configured to engage the inner surface 23 of the filter. The force of engagement between the lower rollers 12 and the filter 1 1 ensures rotation of the lower rollers 12 by the filter 1 1. In the operational position, as shown for example in Fig 1 , the two lower rollers 12 are arranged to extend generally parallel to the axis of rotation of the filter 1 1 and are locatable on the inner surface 23 of the filter 1 1 equidistant either side of an uppermost portion 27 of the inner surface 23 of the filter 1 1. The first and second ends 13, 14 of the lower rollers 12 comprise bearings 53 for rotatable engagement between the ends 13, 14 of the lower rollers 12 and the supports 15, 16 thereof. In the preferred embodiment as shown in the drawings, the second supports 16 may be formed by a flange or crossbar 69 locatable on the gate or hatch 22 which extends across the second ends 14 of both lower rollers 12 providing support to the lower rollers 12 via the bearings 53. Similarly, the first supports 15 may be formed by a flange or crossbar 70 locatable on the supporting frame 25 of the apparatus 10 which extends across the first ends 13 of both lower rollers 12 providing support to the lower rollers 12 via the bearings 53. The flange or crossbar 70 supporting the first end 13 of the lower rollers 12 from beneath in combination with the upper retaining member 60 preventing movement of the first end 13 of the lower rollers 12 results in the lower rollers 12 being retained in position between the flange or crossbar 70 and the upper retaining member 60.

The slurry processing apparatus comprises a liquid tray 28 formed for receiving a liquid portion of the slurry. The liquid tray 28 is locatable within the hollow inner portion 18 of the filter 1 1 and first and second liquid tray supports 63, 64 are configured to support the liquid tray 28 proximal first and second ends 65, 66 thereof which extend from the first and second open ends 19, 20 of the filter 1 1 to engage with the first and second liquid tray supports respectively. The first liquid tray support 63 is a fixed support and the second liquid tray support 64 is a movable support located on the gate or hatch 22. The second liquid tray support 64 may therefore be moved such that the liquid tray 28 can be removed from the inner hollow portion 18 of the filter 1 1. The first liquid tray support 63 comprises three bolts which secure the liquid tray in the operational position even without the presence of the second liquid tray support 64. The bolts are insertable through bores 70 in the liquid tray 28 to secure the first end of the liquid tray 65 to a fixed side portion 67 of the apparatus such that the liquid tray 28 is retained in the operational position when the second liquid tray support 64 is removed. The second liquid tray support 64 is a flange 64 locatable on the gate or hatch 22 such that the second end 66 of the liquid tray rests upon the flange 64 when the gate or hatch 22 is closed. The liquid tray 28 has a lip formation 68 on its second end 66 formed for resting on the flange 64. The liquid tray 28 is a generally wedge shaped liquid tray 28 which, when viewed in plan view, is narrower at its second end 66 than at its first end 65, and comprises two long sides of generally equal length extending between the first and second ends 65, 66. The sides of the liquid tray define a sunken tray surface therebetween. The liquid tray comprises sloped surfaces 52 configured to encourage run-off of the liquid portion of the slurry from the apparatus 10. The bolts fix the liquid tray 28 at or about the first end 65 thereof forming a cantilever arrangement when the second liquid tray support 64 is removed.

In the drawings, there is shown a slurry processing apparatus 10 comprising a filter drive arrangement 29 in operable engagement with the filter 1 1 and configured to drive axial rotation of the filter 1 1. The apparatus further comprises double action hydraulic actuation cylinders 30 for selectably engaging and disengaging the filter drive arrangement 29 from the filter 1 1 between an engaged configuration (as shown in Fig. 1 ) and a disengaged configuration (as shown in Figure 5). As such that the filter 1 1 may be removed, replaced, or have maintenance carried out thereon in the disengaged configuration. The filter drive arrangement 29 comprises four springs 31 configured to bias at least a portion of the filter drive arrangement 29 into contact with the filter 1 1 when the filter drive arrangement 29 is in the engaged configuration. The force applied by the hydraulic actuation cylinders 30 is sufficient to overcome the biasing force exerted by the springs 31 in order to engage the filter drive arrangement 29 with the filter 1 1 in the engaged configuration. The operation of the hydraulic actuation cylinders 30 is carried out via a controller 34 which is manually operated by an operative. The filter drive arrangement comprises a motor 54 in operable engagement with a pair of drive rollers 32, the drive rollers 32 being configured to roll along an outer surface 33 of the filter 1 1 in the engaged configuration, driving rotation thereof. The motor 54 is in operable engagement with the at least one drive roller via a cog and chain arrangement 43.

The filter 1 1 comprises two circumferential flanges 35, 36 extending from the outer surface 33 thereof in a generally radial direction. The circumferential flanges 35, 36 are formed for engagement with two end faces 37, 38 of the drive rollers 32 such that this engagement guides correct locating of the filter 1 1 relative to the drive rollers 32 and as a consequence relative to the rollers 12.

Advantageously, this means that the filter 1 1 may be freely removed from the lower rollers 12 with minimal lifting of the filter 1 1 , a general sliding motion being generally sufficient. Prior art devices comprise a filter having an inward facing flange projecting from the inner surface of the filter which is formed for engaging the ends of the lower rollers (rollers 12 of the present invention) and as such, if this filter flange arrangement was applied to the present invention, the filter would still need to be raised to disengage this inward facing flange in order to remove the filter.

The biasing force applied by the springs 31 is sufficient such that, in the engaged configuration, rotation of the drive rollers 32 causes rotation of the filter 1 1. The two drive rollers 32 extend generally parallel to an axis of rotation of the filter 1 1 and are located on the outer surface 33 of the filter 1 1 equidistant either side of an uppermost portion 39 of the outer surface 33 of the filter 1 1 in the engaged condition. The drive rollers 32 are connected to a pivot 41. The double acting hydraulic actuation cylinders 30 are in operable engagement between the filter drive arrangement 29 the lower supporting frame 25 of the apparatus 10. The filter drive apparatus 29 is a hinged arrangement configured to rotate, about a hinged connection 42, into the engaged configuration with the filter 1 1 wherein the drive rollers 32 engage the filter 1 1 as previously herein described. In use, a method of removing a filter 1 1 in a slurry processing apparatus 10 comprises the steps of raising at least a portion of an upper section 40 of the apparatus such that drive rollers 32 become disengaged from the filter 1 1 , and retaining lower rollers 12 at a first end 13 using a retaining fixture 17 such that lower rollers 12 remain in their operational position even after removal of a second support from the second end thereof. The method further comprising opening a gate or hatch 22 such that a support for a second end 14 of the lower rollers 12 located on the gate or hatch 22 is removed and passing the filter 1 1 over the second end of the lower rollers 12, and removing the filter 1 1 from the slurry processing apparatus. In a preferred embodiment as shown in the drawings, the portion of the upper section 40 of the apparatus 10 is raised hydraulically. Where a replacement filter 1 1 is required, the method further comprises the step of passing a replacement filter 1 1 over the second end 14 of the lower rollers 12, towards the first end 13 thereof. The replacement filter 1 1 is located such that two circumferential flanges 35, 36 extending from the outer surface 33 thereof engage with two end faces 37, 38 of the drive rollers 32. The method further comprises the step of closing the gate or hatch 22 such that the second support 16 supports the second end 14 of the lower rollers 12 and releasing the retaining fixture 17.

Figs. 6 to 9 best illustrate the removable filter 1 1 for the slurry processing apparatus 10 which comprises an open ended cylindrical body defining inner 23 and outer 33 cylindrical surfaces, and two circumferential flanges 35, 36 extending from the outer surface thereof in a radial direction. The circumferential flanges 35, 36 are located proximal each open end 19, 20, of the filter 1 1. At least a portion of the filer body comprises apertures sized such that the fluid portion of the slurry may pass therethrough at a sufficient rate. The apertures of the filter may also be sized such that solid portions of slurry may be forced therethrough by the action of one or more of the rollers 12, 32. In use, the two circumferential flanges 35, 36 extending from the outer surface 33 thereof engage with two end faces 37, 38 of the drive rollers 32. As such, whilst in the typical embodiment the flanges 35, 36 extend radially, the flanges 35, 36 may extend in any such manner which facilitates engagement with two end faces 37, 38 of the drive rollers 32. Moreover, the circumferential flanges need not necessarily be flanges and could instead be any feature attached to or formed integrally of the filter 1 1 such that the attached or formed feature facilitates engagement with the two end faces 37, 38 of the drive rollers 32.

The invention is not limited to the embodiment(s) described herein but can be amended or modified without departing from the scope of the present invention.