This invention relates to a material sampling apparatus. More particularly, but not exclusively, this invention relates to a material sampling apparatus for use in dry and wet applications. The invention also extends to a method of separating material from a first feed of material for sampling purposes.

BACKGROUND TO THE INVENTION

Material sampling apparatuses or samplers are well known and widely used in a wide range of industries such as, but not being limited to, the minerals, food processing and fertilizer industries. Material samplers are intended to extract small, accurate and reproducible samples of a product consignment or lot, representative of a larger whole, to analyse the sample in order to qualify and quantify certain properties, elements, constituents or ingredients of the product in question.

A sample can only be truly representative of the larger whole, if the sampling occurs absolutely at random. No preferential selection of any nature is allowable. Sampling theory dictates that every single particle, irrespective of the property thereof, must have an equal opportunity of entering a sampler off-take inlet or cutter, without being rejected on entry. This represents the biggest challenge in the field of sampling. The importance of achieving a truly representative sample lies in the fact that particles of different properties, whether size, density, shape or any other physical property, have different material qualities and chemical compositions. This holds especially true in the minerals industry, where the metal or element content of the ore is a function of the size of the particles.

Material samplers can be classified with regards to their desired outcome or application, and in this regard, two of the main types which are relevant with regards to the current invention are discussed further below.

The first type of material sampler samples an entire stream of material at discrete intervals and is used to collect for later on analysis and measurement of certain properties or content of the material stream. Samples are generally extracted at discrete, predetermined intervals, after which the sample cutter is withdrawn from the stream of material. Such samplers are commonly referred to as cross-stream samplers and can extract a truly representative sample only at discrete intervals from process streams.

The second type of material sampler continuously samples only part of a stream of material and is typically used as feedback in control systems, in order to quantify adjustments needed to certain parameters of a metallurgical or plant process. In order to obtain a truly representative sample of the material stream, this type of sampler needs to be exposed to the entire stream of material over a period of time and not as the case is with current in-stream designs. Being merely exposed to part of the stream of material at all times, does not itself guarantee extracting a representative sample of the material stream and will not lead to sample integrity. Positioning and geometry of an off-take inlet in a process stream, can easily favour certain particles, resulting in inaccurate data.

Often, the layout of the plant is such that the headroom or clearance available for sampling equipment is very limited, and therefore compact sampling equipment is desirable.

OBJECT OF THE INVENTION

It is accordingly an object of the present invention to provide a material sampling apparatus that will, at least partially, alleviate the abovementioned problems and/or that will be a useful alternative to existing material sampling apparatuses of the type described above.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a material sampling apparatus comprising:

- a first inlet for receiving a first feed of material;

- a first outlet for discharging the first feed of material; and

- a first material separating assembly including a second inlet for receiving a second feed of material, being a portion of the first feed, to separate such second feed from the first feed, the second inlet being displaceable in order to receive material at a plurality of positions in a cross-sectional area of the first feed.

The second inlet may be displaceable in order to receive material at any position in an annular region in the cross-sectional area of the first feed.

There is provided for the second inlet to be displaceable along a plane being orientated perpendicular to the direction of movement of the first feed.

Preferably, the second inlet may be rotatably displaceable about an axis extending along the direction of movement of the first feed.

The material sampling apparatus may further include a first casing being in material flow communication with the first inlet and first outlet wherein the first feed is permitted to enter and to pass through it, the first casing enclosing and being displaceable with the second inlet.

The first casing may define a first recess in a side wall therein into which the second inlet may, at least partially, protrude, such that the second inlet overlaps with the first casing, when viewed along the direction of movement of the first feed.

The first material separating assembly may also include:

- a first collection housing being in material flow communication with the second inlet wherein the second feed is permitted to enter and to pass through it; - a second outlet for discharging the second feed; and

- a first material deflector located upstream from the second inlet for directing the first feed radially outwardly.

The first material deflector may be conically-shaped.

The second inlet may be defined between a first pair of opposing flared blades which are arranged wherein the second inlet gradually widens in a radially outwardly direction.

Still further according to the invention, the blades of the first pair of blades may be angled with respect to the direction of material feed, wherein the cross-sectional area of the second inlet increases in a downstream direction to enhance the flow of material through the second inlet.

The material sampling apparatus further may include first drive means for displacing the second inlet.

The first drive means may include:

- a first motor;

- a first set of teeth arranged about the first casing; and

- a first connecting element being connected to the first motor and the first set of teeth in order to transmit rotational motion from the first motor to the first casing. The material sampling apparatus may still further include a second material separating assembly located downstream from the first material separating assembly and including a third inlet for receiving a third feed of material, being a portion of the second feed, to separate such third feed from the second feed, the third inlet being displaceable in order to receive material at a plurality of positions in a cross-sectional area of the second feed.

The third inlet may be displaceable in order to receive material at any position in an annular region in the cross-sectional area of the second feed.

There is provided for the third inlet to be displaceable along a plane being orientated perpendicular to the direction of movement of the second feed.

Preferably, the third inlet may be rotatably displaceable about an axis extending along the direction of movement of the second feed.

The material sampling apparatus may further include concentric inner and outer casings, the inner casing being located downstream from the first collection housing and is in material flow communication with it wherein the second feed is permitted to enter and pass through it, and the outer casing being located downstream from the first casing and is in material flow communication with it wherein the first feed is permitted to enter and pass through it. The inner casing may enclose and be displaceable with the third inlet. Similarly, the outer casing may enclose and be displaceable with the inner casing. The inner and outer casings may define an annular flow path in between them for the first feed. The inner casing may define a second recess into which the third inlet may, at least partially, protrude, such that the third inlet overlaps with the inner casing, when viewed along the direction of movement of the first feed.

The second material separating assembly may also include:

- a second collection housing being in material flow communication with the third inlet wherein the third feed is permitted to enter and to pass through it;

- a third outlet for discharging the third feed; and

- a second material deflector located upstream from the third inlet for directing the second feed radially outwardly.

The second material deflector may be conically-shaped.

The third inlet may be defined between a second pair of opposing flared blades which are arranged wherein the third inlet gradually widens in a radially outwardly direction.

Still further according to the invention, the blades of the second pair of blades may be angled with respect to the direction of material feed, wherein the cross-sectional area of the third inlet increases in a downstream direction to enhance the flow of material through the third inlet.

The material sampling apparatus further may include second drive means for displacing the third inlet. The second drive means may include:

- a second motor;

- a second set of teeth arranged about the outer casing; and

- a second connecting element being connected to the second motor and the second set of teeth in order to transmit rotational motion from the second motor to the outer casing.

According to an example embodiment of the invention, the second and third inlets may be displaceable independently from each other including any one of:

- rotatable in opposing directions;

- rotatable in similar directions;

- rotatable at different speeds; and

- rotatable at similar speeds.

Even further according to the first aspect of the invention, the material to be sampled may include any one of slurry materials, dry fine materials and ores of varying average diameters.

According to a second aspect of the invention, there is provided a method of separating material from a first feed of material for sampling purposes, the method including the steps of:

- providing an upstream inlet that is in-line with the moving first feed of material for receiving a second feed of material, being a portion of the first feed; and - displacing the inlet in the first feed in order to receive the material at a plurality of positions in a cross-sectional area of the first feed.

The inlet may be displaceable in order to receive material at any position in an annular region in the cross-sectional area of the first feed.

There is provided for the inlet to be displaced in a plane being orientated perpendicular to the direction of movement of the first feed.

Preferably, the inlet may be rotatably displaced about an axis extending along the direction of movement of the first feed.

The method may further include the step of deflecting at least some of the first feed in a radially outwardly direction towards the inlet.

The method may also include the steps of

- providing a downstream inlet that is in-line with the moving second feed of material for receiving a third feed of material, being a portion of the second feed; and

- displacing the downstream inlet in the second feed in order to receive the material at a plurality of positions in a cross-sectional area of the second feed.

These and other features of the invention are described in more detail below. BRIEF DESCRIPTION OF THE FIGURES

One embodiment of the invention is described below, by way of a non-limiting example only, and with reference to the accompanying figures in which:

Figure 1 is a schematic perspective view of a material sampling apparatus according to the invention;

Figure 2 is a schematic perspective view of the material sampling apparatus of figure 1 , without peripheral safety covers;

Figure 3 is a section view along line ΙΙΙ-ΙΙΓ in figure 2;

Figure 4 is a partial exploded view of a central part of the material sampling apparatus shown in figure 1 ;

Figure 5 is a sectioned side view of the central part of the material sampling apparatus shown in figure 4;

Figures 5A & 5B are an enlarged views of areas accordingly marked in figure 5;

Figure 6 is a perspective view of a first material separating assembly forming part of the material sampling apparatus of figure 1 ; Figure 6A is a similar view to that of figure 6, without elements indicated in broken lines;

Figure 7 is a perspective view of a second material separating assembly forming part of the material sampling apparatus of figure 1 ; and

Figures 7A & 7B are similar views to that depicted in figure 7, with elements shown in broken lines progressively not shown.

DETAILED DESCRIPTION OF THE INVENTION

With reference to figures 1 to 5, a particulate material sampling apparatus according to the invention is generally indicated by reference numeral 10.

Referring particularly to figures 4 to 5B, the apparatus 10 includes a first inlet 12, defined by an inlet casing 14, for receiving a first feed of material A of which a sample is to be extracted by the apparatus 10, and a first outlet 16 at an opposing operatively lower end thereof, being defined by an outlet casing 18, for discharging the first feed A.

The apparatus 10 also includes a first material separating assembly 20 including a second inlet 22 for receiving a second feed of material B, being a portion of the first feed A, in order to separate such second feed B from the first feed A for sampling purposes. The second inlet 22 is displaceable C along a first plane D being orientated substantially perpendicular to the normal direction of movement of the first feed A, in order to receive material at a plurality of positions in a cross-sectional area of the first feed A. According to this example embodiment, the second inlet 22 is rotatably displaceable C about an axis E, being a vertical axis, extending along the centre of the normal direction of movement of the first feed A, in order to receive material at any position in a first annular region F (see figure 6A) in the first plane D and cross-sectional area of the first feed A.

A first upstream tubular-shaped casing 24 and an adjacent downstream outer tubular casing 26 connect the inlet and outlet casings 14 and 18 to each other to ensure that first inlet 12, first outlet 16 and first casing 24 and outer casing 26 are in material flow communication with each other. The first feed A is thus permitted to enter and to pass through the first and outer casings 24 and 26. An inner tubular casing 28 is positioned inside and is enclosed by the outer casing 26 so to be concentric with respect to the outer casing 26, and retained in position by means of a plurality of radially extending first retaining spokes 30. The inner and outer casings 28 and 26 define an annular flow path in between them for the first feed A to pass through.

The first material separating assembly 20 is located inside the first casing 24 and includes a first collection housing 32, in material flow communication with the second inlet 22, wherein the second feed B is permitted to enter and to pass through it. The inner casing 28 is located downstream from the first collection housing 32 and is in material flow communication with it wherein the second feed B is subsequently permitted to enter and to pass through it. The first collection housing 32 is retained in position by means of a plurality of radially extending second retaining spokes 34. The first material separating assembly 20 also includes a second outlet 36 for discharging the second feed B, and a first conically-shaped material deflector 38 located upstream from the second inlet 22. The first material deflector 38 is located in the centre of the first casing 24 and directs at least a portion of the first feed A radially outwardly towards the second inlet 22. Therefore, the entire first feed A passes through the first annular region F and has an opportunity of reporting to the second inlet 22. The first casing 24 is displaceable with the second inlet 22. The annular region F extends from the periphery of the deflector 38 to the inner diameter of the first casing 24.

The second inlet 22 is defined between a first pair of opposing flared blades 40 which are arranged wherein the second inlet 22 gradually widens in a radially outwardly direction. Preferably, at their narrowest point, the distance between the blades 40 exceeds three times the diameter of the nominally largest particle to be sampled of the first feed A. The blades 40 of the first pair of blades are furthermore angled by less than about five (5) degrees with respect to the direction of material feed, wherein the cross-sectional area of the second inlet 22 slightly increases in a downstream direction, to enhance the flow of material through the second inlet 22 and to ensure that material that is intended to enter the second inlet 22 does so, rather than being unduly rejected upon entry.

The first casing 24 defines a first recess 42 in a side wall thereof into which the first pair of blades 40, and thus the second inlet 22, at least partially, protrudes, such that the second inlet 22 overlaps with the first casing 24, when viewed along the direction of movement of the first feed A. A first hatch 44 is also provided in the first casing 24 at a location corresponding to that of the first recess 42, for facilitating access to the second inlet 22, typically for maintenance purposes.

Turning to figures 2 and 3, first drive means 46 is provided for rotatably displacing the second inlet 22 and first casing 24. The first drive means 46 includes a first motor 48, mounted on an upright support frame 50, a first set of teeth 52 arranged about the first casing 24, and a first connecting element, in the form of first wheel 54 with sprockets that connects the first motor 48 and the first set of teeth 52 in order to transmit rotational motion from the first motor 48 to the first casing 24.

Referring particularly to figures 4 to 5B, the sampling apparatus 10 also includes a second material separating assembly 56, located downstream from the first material separating assembly 20, and including a third inlet 58 for receiving a third feed of material G, being a portion of the second feed B, in order to separate such third feed G from the second feed B for sampling purposes. The third inlet 58 is displaceable H along a second plane J being orientated substantially perpendicular to the normal direction of movement of the second feed B, in order to receive material at a plurality of positions is a cross-sectional area of the second feed B. According to this example embodiment, the third inlet 58 is rotatably displaceable H about the axis E, in order to receive material at any position in a second annular region K (see figure 7B) in the second plane J and cross-sectional area of the second feed B.

Referring particularly to figures 7 to 7B, it is shown that the second material separating assembly 56 is located inside and enclosed by the inner casing 28 and includes a second collection housing 60 being in material flow communication with the third inlet 58, wherein the third feed G is permitted to enter and pass through it. The second collection housing 60 is retained in position by means of a plurality of radially extending third retaining spokes 62. The first, second and third feeds A, B and G flow concentric with respect to each other.

The second material separating assembly 56 also includes a third outlet 64 for discharging the third feed G, and a second conically-shaped material deflector 66 located upstream from the third inlet 58. The second material deflector 66 is located in the centre of the inner casing 28 and directs at least a portion of the second feed B radially outwardly towards the third inlet 58. Therefore, the entire second feed B passes through the second annular region K and has an opportunity of reporting to the third inlet 58. The inner casing 28 is displaceable with the outer casing 26 and the third inlet 58. The annular region K extends from the periphery of the deflector 66 to the inner diameter of the inner casing 28.

Similar to above description with regards to the second inlet 22, the third inlet 58 is defined between a second pair of opposing flared blades 68 which are arranged wherein the third inlet 58 gradually widens in a radially outwardly direction. Preferably, at their narrowest point, the distance between the blades 68 exceeds three times the diameter of the nominally largest particle to be sampled of the second feed B. The blades 68 of the second pair of blades are furthermore angled by less than about five (5) degrees with respect to the direction of material feed, wherein the cross-sectional area of the third inlet 58 slightly increases in a downstream direction, to enhance the flow of material through the third inlet 58 and to ensure that material that is intended to enter the third inlet 58 does so, rather than being unduly rejected upon entry.

The inner casing 28 defines a second recess 70 in a side wall thereof into which the second pair of blades 68, and thus the third inlet 58, at least partially, protrudes, such that the third inlet 58 overlaps with the inner casing 28, when viewed along the direction of movement of the second feed B. A second hatch 72 is also provided in the inner casing 28 and a third hatch 74 in the outer casing 26 at respective locations corresponding to that of the second recess 70, for facilitating access to the third inlet 58, typically for maintenance purposes.

Turning to figure 2, similar to the first drive means 46 described above, second drive means 76 is provided for rotatably displacing the third inlet 58 and the outer and inner casings 26 and 28. The second drive means 76 includes a second motor 78, mounted on the upright support frame 50, a second set of teeth 80 arranged about the outer casing 26, and a second connecting element, in the form of a second wheel 82 with sprockets that connects the second motor 78 and the second set of teeth 80 in order to transmit rotational motion from the second motor 78 to the outer casing 26.

It should be appreciated that second and third inlets 22 and 58 will be displaceable independently from each other, including being rotatable in opposing or similar directions, and rotatable at different or similar speeds. As such, each assembly 20 and 56 is able to rotate independently to ensure that their respective inlets 22 and 58 don't align. The inlet and outlet casings 14 and 18 include radially extending flanges 84 which form part of the upright support frame 50. The frame 50 further includes a plurality of spaced apart tie rods 86 which are located at and extend between edge regions of the opposing flanges 84. Peripheral planar safety screens or covers 88 extend between peripheries of the opposing flanges 84 to enclose all moving parts of the apparatus 10 for safety purposes. The covers 88 are removably attached to the flanges 84 should access be needed to a concealed part. The frame 50 also includes aligning means, in the form of circumferentially spaced idler wheels 90 mounted on the frame 50. The wheels 90 urge against the apparatus 10, more specifically against the outer casing 26, to ensure that the first and outer casings 24 and 26 are axially aligned, whilst accommodating rotational movement. The wheels 90 are displaceable to and from the apparatus 10 in order to adjust the apparatus' 10 alignment.

The second material separating assembly 56 is proportionally sized such that it can accommodate the second feed B that has been separated from the first feed A, by the first material separating assembly 20, whilst permitting the remainder of the first feed A, not so separated, to pass by the outside of the inner casing 28. Preferably, the material to be sampled could include any one of slurry materials, dry fine materials and ores of varying average diameters. Preferably, ores of particle diameter smaller than about four (4) millimetres, or foodstuffs typically of particle diameter smaller than ten (10) millimetres would be separated using the material sampling apparatus 10. An off-take duct 92 is attached to the outlet casing 18 and is in register with the third outlet 64, for conveying the third feed G away from the apparatus 10 to be analyzed. The duct 92 is retained in position by means of a plurality of radially extending fourth retaining spokes 94.

In use, and referring to figure 5, the first or main feed A of material enters the material sampler 10 through the first inlet 12. The feed A enters the first tubular casing 24 and some of the material that is positioned towards the centre of the feed A, is deflected in a radially outwardly direction by the first deflector 38. A portion of the first feed A is separated from the first feed A as the second feed B by entering the second or upstream inlet 22, which is in-line with and continuously rotates in the first feed A. The remainder of the first feed A, which did not report to the second inlet 22, is permitted to pass around the housing 32 and through the first casing 24 and thereafter between the outer and inner casings 26 and 28.

Upon exiting the first collection housing 32, the second feed B enters the second separating assembly 56. Similarly, some of the material that is positioned towards the centre of the feed B is deflected in a radially outwardly direction by the second deflector 66. A portion of the second feed B is separated from the second feed B for sampling purposes as the third feed G by entering the third inlet 58, which is in-line with and continuously rotates in the second feed B. The remainder of the second feed B, which did not report to the third inlet 58, is permitted to pass through the inner casing 28 and thereafter rejoins the first feed A. The third feed C exits the sampler 10 through the duct 92 for testing purposes. It should be understood that the invention teaches a material sampling apparatus 10 that facilitates extraction of small, accurate and reproducible samples of a product consignment or lot, representative of a larger whole, to analyse the sample in order to qualify and quantify certain properties, elements, constituents or ingredients of the product in question. The sample is extracted absolutely at random as no preferential selection of any nature is afforded to any material irrespective of its location, size, or composition. Every single particle, irrespective of the property thereof, has an equal opportunity of reporting to the off-take duct 92.

It will be appreciated by those skilled in the art that the invention is not limited to the precise details as described herein and that many variations are possible without departing from the scope of the appended claims. As such, the present invention extends to all functionally equivalent structures, methods and uses that are within its scope. For example, drive means 46 and 76 could include a belt, chain and/or direct gear engagement drives.

The description is presented by way of example only in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention. The words which have been used herein are words of description and illustration, rather than words of limitation.