Eriez Manufacturing Co. v Newcastle Innovation Limited - [2014] APO 59

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Eriez Manufacturing Co. v Newcastle Innovation Limited [2014] APO 59

Patent Application: 2008221231

Title:Method and apparatus for flotation in a fluidized bed

Patent Applicant:                   Newcastle Innovation Limited
Opponent:  Eriez Manufacturing Co.
Delegate:  Rhys Munzel
Decision Date:  12 August 2014
Hearing Date:  20 May 2014
Catchwords:  PATENTS – novelty – inventive step – mineral separation – purposive construction applied

Representation: Patent applicant: Ms Rebekah Gay of Herbert Smith Freehills
Opponent:Mr Ernest Graf & Mr Andrew Cale of Fisher Adams Kelly

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Patent Application: 2008221231
Title:Method and apparatus for flotation in a fluidized bed

Patent Applicant: Newcastle Innovation Limited
Date of Decision: 12 August 2014
DECISION
The opposition fails on all grounds. Subject to an appeal against this decision the application is to proceed to grant. Costs are awarded against the opponent according to Schedule 8.
REASONS FOR DECISION
Background

Patent application 2008221231 (“the application”) in the name of Newcastle Innovation Limited (“Newcastle”) was examined and accepted by the Commissioner, and subsequently opposed by Eriez Manufacturing Company (“Eriez”). As Newcastle requested examination before 15 April 2013 substantive amendments of the Patents Act 1990 (Cth) (“the Act”) brought about by the Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (Cth) (“Raising the Bar Act”) do not apply to this opposition.
Newcastle and Eriez each rely on evidence provided by declarants. Eriez’s evidence in support was provided by Mr Clinton Priddle, Mr Ernest Graf, Dr Jaisen Kohmuench and Mr Glen Oswald. Newcastle’s evidence in answer was provided by Professor Tim Napier-Munn. Eriez’s evidence in reply was provided by Professor Norman Epstein, Dr Gerald Luttrell and again by Dr Kohmuench. Many declarations included annexed exhibits. I will refer to the evidence where appropriate by, when for example drawing on Dr Kohmuench’s evidence, referring to his first declaration as “Kohmuench 1” and his first exhibit as “JK-1”.
The hearing occurred on 20 May 2014. Mr Ernest Graf and Mr Andrew Cale attended on behalf of Eriez while Ms Rebekah Gay attended on behalf of Newcastle. Professor Graeme Jameson, the named inventor for the application, also attended the hearing.
Onus
As amendments brought about by the Raising the Bar Act do not apply the onus in these proceedings rests with Eriez to clearly establish its case. In establishing that any ground of opposition succeeds, the Commissioner should be “clearly satisfied that the patent, if granted, would not be valid” (F. Hoffman-La Roche AG v New England Biolabs Inc [2000] FCA 283 at [67]).
Grounds of opposition
Eriez relied on the following grounds of opposition:
- Lack of novelty
- Lack of inventive step
- Lack of a manner of manufacture
- Lack of clarity
- Lack of fair basis
- Lack of full description
The nature of the disclosed invention
Before construing the specification, I note what Middleton J said in Eli Lilly and Company Limited v Apotex Pty Ltd [2013] FCA 214, 100 IPR 451 at [139]:
“It is well settled that the Court should, from the outset, approach the task of patent construction with a generous measure of common sense. The Court must place itself in the position of a person skilled in the relevant art, being the subject matter of the patent. From this perspective, the patent is to be read as a whole, in the context of the specification and in light of the prevailing common general knowledge and state of the relevant art at the priority date.”
The application describes the invention as relating to the froth flotation process for the separation of particles, in particular to improving the recovery of coarse particles in froth flotation machines (at page 1 lines 5-8).
Background to the invention
The application provides a background to the invention as follows. Froth flotation is a known process for separating desired minerals from undesired waste material. In mining an ore body will typically contain a relatively small proportion of desired minerals disseminated throughout a host rock. The host rock is crushed and/or ground to smaller particles in preparation for separating the desired minerals via froth flotation (at page 1 lines 11-15). During froth flotation the crushed/ground particles are suspended in water and reagents may be added to make the surfaces of the desired minerals hydrophobic while the surfaces of the undesired waste material remain hydrophilic. Air bubbles are added to the water, which attach to the hydrophobic mineral particles (at page 1 lines 15-21). The air bubbles carry the desired mineral particles to a froth layer formed on the top surface of the water. The froth layer will discharge over the lip of the froth flotation cell, carrying the desired minerals. Meanwhile the undesired waste materials are discharged with the liquid to a tailings disposal facility (at page 1 line 23 to page 2 line 6).
The specification teaches that the formation of a froth layer is an important characteristic of the froth flotation process. As discussed at page 2 lines 8-13:
“In a stable froth layer, froth is discharged over the lip of the flotation cell, being continuously replaced by bubbles with attached particles, and entrained particles, from the pulp or slurry in the cell beneath. While moving towards the overflow lip, the froth drains and entrained particles are able to flow back into the pulp, enhancing the purity or grade of the flotation product.”
The specification therefore teaches that the froth layer improves separation selectivity by draining liquid containing waste material from the bubbles before the bubbles leave the cell.
There is a limit to the size of particles that respond well to flotation. As the size of the particles increases they will be less likely to remain attached to the bubbles, meaning the recovery of desired minerals will decrease. The application teaches that this is the result of turbulence within the cell, characterised by eddies having a wide range of diameters and rotational speeds. When a bubble is trapped in the centre of an eddy, it will rotate at the rotational frequency of the eddy, and if a large particle is attached to the bubble, it will be flung away by centrifugal force (at page 2 line 21 to page 3 line 8).
The application refers to two prior art patent documents. They are: US 4960509 A (McNEILL) 2 October 1990 (“McNeill”) and US 6425485 B1 (MANKOSA et al.) 30 July 2002 (“Mankosa”). I note that Eriez relies on Mankosa as relevant prior art for novelty and inventive step as I discuss below.
The application cites McNeill to exemplify one of the prior art attempts to improve the recovery of coarse particles in flotation (at page 7 lines 4-22). According to the application, the process taught by McNeill modifies a mechanical flotation cell by incorporating a vertical baffle dividing the cell into a feed zone and a flotation zone. Crushed ore suspended in water passes from the feed zone through an impellor where it is brought into contact with air bubbles. The aerated pulp rises through a perforated plate toward the top of the cell, where the bubbles disengage from the liquid and pass into the froth layer. The application teaches that the impeller will inevitably introduce high energy dissipation rates throughout the cell, as well as high levels of turbulence which, as discussed above, will reduce recovery of coarse particles (at page 7 lines 14-18).
The application then refers to Mankosa (at page 8 line 1 to page 9 line 4) as teaching a process in which the density of one type of particles is decreased by the adherence of air bubbles, thereby facilitating the separation of such particles from others of higher density in a fluidized bed separator. A feed containing particles in suspension is introduced near the top of a rectangular cell. Provision is made to withdraw solids and liquid from a dewatering cone at the base of the cell, and also from a collection launder at the top of the cell. A fluidized bed forms in the cell, so that particles whose density is less than the average density of particles in the bed float to the top. The bed is fluidized with fresh water, into which air bubbles are injected. The bubbles attach to any particles that are hydrophobic and carry them to the surface of the vessel and into the collection launder, along with materials of low density existing in the feed. The application teaches that the Mankosa device is deficient because, as it primarily separates particles on the basis of density, it cannot distinguish between particles that are naturally less dense and particles made superficially less dense through attachment to air bubbles (at page 8 line 15 to page 9 line 1). The application further identifies the Mankosa device to require use of clean water as the fluidizing liquid, and that it is desirable to minimise use of water in many mining locations (at page 9 lines 2-4).
The aim of the invention
The application sets out two objects of the invention. At page 3 lines 16-20:
“There is a need for a way of conducting flotation that substantially eliminates turbulence from the environment in which the capture of particles by bubbles is performed. It is an object of the present invention to reduce turbulence in a flotation cell.”
and at page 7 lines 20-23:
“It is an object of the present invention to create an environment that is conducive to capture and retention of coarse particles and which does not require mechanical agitation.”
I conclude that the broader aim of the invention is to improve the flotation of coarse particles by reducing or substantially eliminating turbulence within the cell.
The nature of the invention described
The description teaches that the reduction of turbulence (and the resulting improvement in capturing coarse particles) is achieved by incorporating a fluidized bed into the froth flotation cell below a settling zone (at page 24 lines 5-19). Figure 1 of the present application is reproduced below wherein a fluidized bed 18 is provided in the lower portion 13 of the flotation vessel 1.
A fluidized bed is exemplified in terms of a bed of solid particles provided in a vessel with a uniform upward flow of a liquid (at page 2 line 21 to page 7 line 3). At a certain liquid velocity, the upward flow will become sufficient to support the effective mass of the particles in the bed. From my understanding the upward flow will balance gravitational forces such that particles will suspend in the liquid, causing the bed of particles itself to behave as a fluid. The application teaches that a fluidized bed allows for contact between particles and bubbles (and formation of bubble particle aggregates) while providing a reduced level of turbulence, and dampening of eddies, compared to prior art techniques (at page 24 lines 5-19).
Returning to Figure 1, feed to the flotation vessel 1 enters with the fluidization liquid (i.e. water) via a distribution system 3 comprising a number of entry pipes 4. The feed enters the fluidized bed 18, where it contacts air bubbles introduced to the bed 18 by vertical pipes 7. Hydrophobic particles attach to the air bubbles and rise out of the bed 18 to a froth layer 31. Froth containing the hydrophobic particles is removed via launder 33. Hydrophilic particles 22 which do not attach to the bubbles leave the vessel 1 via a tailings removal launder 14. Hydrophilic particles which rise out of the bed due to entrainment in the wake of the bubbles will enter a settling zone 30 and fall back under gravity to the top of the bed 18 (at page 13 line 21 to page 16 line 3).
Construing the claims
The correct approach to the construction of claims was discussed by Bennett J in H Lundbeck A/S v Alphapharm Pty Ltd [2009] FCAFC 70, 81 IPR 228 at [118] – [120]:
"Words in a claim should be read through the eyes of the skilled addressee in the context in which they appear. Words used in a specification are to be given the meaning which the person skilled in the art would attach to them, having regard to his or her own general knowledge and to what is disclosed in the body of the specification … while the claims define the monopoly claimed in the words of the patentee's choosing, the specification should be read as a whole … it is not permissible to read into a claim an additional integer or limitation to vary or qualify the claim by reference to the body of the specification … terms in the claim which are unclear may be defined or clarified by reference to the body of the specification".
The application ends with 15 claims and 6 pages of drawings. Claims 1 and 7 are independent claims while claim 15 is an omnibus claim relying of reference to the drawings.
Claim 1
Claim 1 defines:
“A method of separating selected particles from a mixture of particles in a fluid, including the steps of: feeding the mixed particles and fluid into a fluidized bed containing bubbles; allowing the selected particles to attach to bubbles within the fluidized bed and rise to the top of the fluidized bed; allowing bubbles with selected particles attached to rise above the fluidized bed into a settling chamber while removing other particles from the fluidized bed; forming a froth layer of bubbles and attached selected particles at the top of the settling chamber; and removing the selected particles with bubbles from the froth layer.”
A number of terms and phrases used in claim 1 give rise to questions of construction that were the subject of dispute during the hearing:
Feeding the mixed particles and fluid into a fluidized bed
A question arose between the parties as to whether all, or practically all particles, to be separated must enter the fluidised bed or, conversely, whether some particles to be separated could bypass the fluidized bed altogether. In other words, could some particles be separated prior to the mixture of particles entering the fluidized bed? In addressing this question I return to the first three lines of claim 1:
“A method of separating selected particles from a mixture of particles in a fluid, including the steps of:
feeding the mixed particles and fluid into a fluidized bed containing bubbles”
The preamble to the claim firstly requires the existence of a mixture of particles in a fluid. This could for example by constituted by a suspension (at page 2 lines 2-6 of the specification). Use of the definite article “the” prior to “the mixed particles and fluid” indicates that it is the earlier defined mixture of particles in a fluid that must be fed into the fluidized bed. The claim does not necessarily preclude earlier processing steps where for example some particles are removed from a pre-existing mixture of particles. Nevertheless, there must remain “a mixture of particles in a fluid” that is fed into a fluidized bed (Napier-Munn, at paragraphs 57 and 58).
Froth layer
Newcastle submitted that the defined froth layer would be understood by the person skilled in the art as relating to a “bubble-rich structured and stable layer that sits above, and is in equilibrium with, a liquid-rich layer in the flotation cell” (Napier-Munn, at paragraph 31). Newcastle emphasized the purpose of froth layers in froth flotation, being to allow selective drainage from the froth of entrained hydrophilic particles, which would otherwise be discharged with the hydrophobic selected particles (Napier-Munn, at paragraph 31). Eriez submitted that the term “froth layer” did not of itself import any depth or stability limitations, and that a froth layer could be composed of an uncontrolled layer of bubbles lacking “any significant depth” (Kohmuench 2, at paragraph 11) or having “zero depth” (Luttrell at paragraph 23). Dr Kohmuench, in reply to Professor Napier-Munn’s evidence, declared the following (Kohmuench 2, at paragraph 11):
“Mr. Napier-Munn uses a statement from exhibit JK-06, which states that the ‘HydroFloat is operated without a traditional froth’, to infer that there is no froth. In fact, the sentence actually indicates that the HydroFloat does have a froth as seen above, but it is not traditional in the fact that it is not controlled to any significant depth.”
Similarly Dr Luttrell, in reply to Professor Napier-Munn’s evidence, declared (Luttrell at paragraph 23):
“Napier-Munn cannot dismiss Oswald’s declaration since a ‘traditional froth’ may be interpreted to mean a deep froth that is controlled at a fixed height. The industrial HydroFloat units currently operating in the field may not have a traditional froth layer in that sense; however, the photograph evidence provided in the current documents (and from the Oswald statements) clearly demonstrates the presence of a froth layer atop the HydroFloat unit, albeit a non-traditional froth layer.”
Dr Kohmuench and Dr Luttrell understand that the term “froth” has a traditional meaning when used in relation to flotation separation and that a froth, as traditionally understood in this context, is controlled to a significant depth. Taking Professor Napier-Munn’s evidence into account (as discussed above), the person skilled in the art would further understand that a significant depth is one which allows for improved selectivity through drainage of liquid and entrained particles.
It may be that the literal or everyday meaning of “froth layer”, as applied outside the flotation context, could include a layer of bubbles lacking any significant depth. However I am satisfied that the term, when purposively construed as part of claim 1, would be understood as relating to a layer of froth having sufficient depth and stability to allow for significant drainage of liquid and entrained particles. I do not consider that the person skilled in the art would find use of the term ambiguous. However to the extent he or she may do so I note that resort to the description would further clarify that the intended meaning is one where the froth layer is a “traditional” froth layer (at page 2 lines 9-13 of the application).
Settling chamber
I will firstly note, and is not in dispute between the parties, that the term “chamber” does not import a requirement that settling occurs in a specifically enclosed space, for example a vessel separate to fluidized bed. A “settling chamber” could be constituted by a settling zone provided above the fluidized bed. At a practical level the present application describes the settling chamber as a relatively placid zone where particles of gangue that may have been entrained in the wake of the bubbles rising out of the fluidized bed are able to fall back under gravity to the top of the fluidized bed (at page 17 lines 16-25). I consider this description to be consistent with the person skilled in the art’s understanding in that the defined settling zone is a region where non-selected particles entrained in a bubble’s wake are able to fall under gravity back into the fluidized bed (Napier Munn, at paragraph 58).
Claim 7
Claim 7 defines:
“Apparatus for separating selected hydrophobic particles from a mixture of particles in a fluid, said apparatus including:
a fluidization chamber arranged to receive a feed of a mixture of particles and fluid into the lower part of the chamber;
fluidization means arranged to supply bubbles and feed into the chamber at such a rate that a fluidized bed of particles is formed within the fluidization chamber;
a settling chamber located directly above and communicating with the fluidization chamber such that selected hydrophobic particles attached to bubbles rising to the top of the fluidized bed float upwardly within the settling chamber;
tailings separation means arranged to remove non-hydrophobic particles from the top of the fluidized bed; and
an overflow launder at the top of the settling chamber arranged to remove the selected hydrophobic particles from a froth layer formed at the top of the flotation cell.”

There are some differences between claims 1 and 7 which require some discussion. Firstly and most obviously claim 7 defines an apparatus whereas claim 1 defines a method. In addition:
·     whereas claim 1 defines feeding a mixture of particles and a fluid into a fluidized bed, claim 7 defines a fluidization chamber arranged to receive a feed of a mixture of particles and fluid into the lower part of the chamber;
·     whereas claim 1 specifies that “other particles” are removed from the fluidized bed, claim 7 defines a tailings separation means arranged to remove non-hydrophobic particles from the top of the fluidized bed;
·     while claim 7 mentions a froth layer, it does so in the context of setting out the configuration of an overflow launder. In this context, while the apparatus must be capable of forming a froth layer, the froth layer is not necessarily part of the apparatus itself.
Claim 15
Claim 15 defines:
“Apparatus for removing selected hydrophobic particles from mixed particles in a fluid when constructed arranged and operable substantially as described herein with reference to the accompanying drawings.”
The apparatus described in the specification best summarised at page 10 lines 7-20. This passage provides a consistory statement for claim 7. The apparatus described therefore is the apparatus of claim 7 configured with reference to the drawings.
Novelty
The general test for lack of novelty is the reverse infringement test. The classic formulation of this test was given by Aickin J in Meyers Taylor Pty Ltd v Vicarr Industries Ltd [1977] HCA 19 at [20], 137 CLR 228 at 235:
"The basic test for anticipation or want of novelty is the same as that for infringement and generally one can properly ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement".
This test is satisfied if the alleged anticipation discloses all the essential features of the invention as claimed (see Nicaro Holdings Pty Ltd v Martin Engineering Co (1990) 91 ALR 513 at 517). Australian courts have often cited, with approval, the words of the UK Court of Appeal in The General Tire & Rubber Company v The Firestone Tyre and Rubber Company Limited [1972] RPC 457 at 485 – 486 (“General Tire”):
"If the prior inventor's publication contains a clear description of, or clear instructions to do or make, something that would infringe the patentee’s claim if carried out after the grant of the patentee's patent, the patentee's claim will have been shown to lack the necessary novelty, that is to say, it will have been anticipated. The prior inventor, however, and the patentee may have approached the same device from different starting points and may for this reason, or it may be for other reasons, have so described their devices that it cannot be immediately discerned from a reading of the language which they have respectively used that they have discovered in truth the same device; but if carrying out the directions contained in the prior inventor's publication will inevitably result in something being made or done which, if the patentee's patent were valid, would constitute an infringement of the patentee's claim, this circumstance demonstrates that the patentee's claim has in fact been anticipated."
If, on the other hand, the prior publication contains a direction which is capable of being carried out in a manner which would infringe the patentee's claim, but would be at least as likely to be carried out in a way which would not do so, the patentee's claim will not have been anticipated, although it may fail on the ground of obviousness. To anticipate the patentee's claim the prior publication must contain clear and unmistakeable directions to do what the patentee claims to have invented: Flour Oxidizing Co. Ltd. v. Carr & Co. Ltd. (1908) 25 R.P.C. 428 at 457, line 34, approved in B.T.H. Co. Ltd. v. Metropolitan Vickers Electrical Co. Ltd. (1928) 45 R.P.C. 1 at 24, line 1). As stated in the General Tire case:
"A signpost, however clear, upon the road to the patentee's invention will not suffice. The prior inventor must be clearly shown to have planted his flag at the precise destination before the patentee."
Mankosa
Eriez submitted that claims 1 and 3 lack novelty in view of Mankosa. In comparing Mankosa with the claims of the application I consider it particularly relevant to discuss the nature and context of what is disclosed in Mankosa. I will therefore begin by discussing what Mankosa discloses as the background art.
The disclosed background art – hindered bed separators
Mankosa identifies that a hindered bed separator is a vessel in which water is evenly introduced across the base of the separator and rises upward (at column 1 lines 47-49). Solids are typically introduced in the upper portion of the vessel and begin to settle against the upward flow at a rate defined by the particle size and density (at column 1 lines 53-55). Rising water and lighter, finer particles flow over the top of the separator and are collected in a launder while denser, coarser particles are typically discharged though the bottom of the unit . The denser, coarser particles will build a bed of teetering (fluidized) solids which, in the region of the bed, increase the apparent density of the water at column 1 lines 55-62). This in turn prevents lighter particles from entering the bed such that they are transported to the overflow launder (at column 1 lines 62-65).
The problem with the background art
Mankosa teaches that traditional fluidized bed separators have the problem of lighter, coarser particles gathering at the top of the teeter bed (fluidized bed) because the teeter water velocity is not sufficient to transport this material to the overflow launder. Eventually these gathering particles will migrate into the teeter bed and leave the cell with the high density particles (at column 1 line 66 to column 2 line 5). While this problem was traditionally overcome by increasing the teeter water velocity, such an approach created a further problem by causing fine, high density particles to the overflow launder, thereby reducing selectivity (at column 2 lines 5-14).
How is this problem overcome?
Mankosa teaches that the aeration of the hindered bed will modify the effective density of one or more species of particles. Aeration is achieved by introducing fine air bubbles with the water supply. The bubbles rise with the upward current and selectively attach to the surface of a particular species (at column 2 lines 38-44). Mankosa teaches that this approach combines the pre-concentration of a hindered bed with the further enhancement of bubble-particles attachment to modify the density of one of the feed components (at column 2 lines 52-60). Mankosa additionally teaches that the bubble-particle attachment is greatly enhanced as a result of the hindered bed (at column 3 lines 29-34). With this approach, coarser particles which would otherwise gather at the top of the teeter bed, eventually enter the bed, and leave the cell with as tailings may be removed from the teeter bed as they are attached to the air bubbles (at column 5 lines 43-57). Mankosa additionally teaches that higher density particles may also be selectively removed with this technique (at column 3 lines 1-5).
The disclosed embodiments
Figs. 1-3 of Mankosa present different views of the disclosed separator, of which Figs. 1 and 3 are reproduced below. The Figs. are discussed columns 4 and 5. The separator comprises a main housing 1 which in turn consists of an upper separation chamber 2 and a lower dewatering cone 3. A feed inlet chamber 4 disperses particles to be separated throughout the cross section of the upper separation chamber 2. Higher density particles establish a teeter bed due to the upward flow of water 5, the teeter bed interface being represented by 36. Particles having a density lower than the apparent density of the teeter bed do not initially enter the bed. Fine, lower density particles are carried to the top of the separator and report to the collection launder 26. Coarse, low density particles will continue to gather at the interface of the teeter bed and eventually migrate into the teeter bed. Bubbles 28 produced by a high-shear device 8 migrate through the teeter bed and selectively attach to the surface of low density particles. The bubble-particle aggregates, having an effective density that is further reduced, subsequently migrate back to the surface of the teeter bed. The bubble particle aggregates build a layer upward from the interface of the teeter bed until they overflow into the collection launder 26. Higher density particles will migrate toward the bottom of upper separation chamber 2 and report to the dewatering cone 3. The underflow product is discharged by control valve 29.
Does Mankosa disclose a froth layer?
Eriez acknowledges that the term “froth” is not used in Mankosa. Eriez directed me to column 5 lines 53-56 of Mankosa, which states:
“The bubble particle aggregates build a layer upward from the interface of the teetering high density solids until they overflow into collection launder 26.”
Eriez additionally referred to the evidence of Professor Napier-Munn where, at paragraph 58 of his declaration, he acknowledged that a froth layer comprises bubble-particle aggregates. Eriez therefor submits that the layer of bubble particle aggregates as disclosed in Mankosa constitutes the defined froth layer. If that is the case Mankosa would appear to disclose a froth layer which originates at the interface of the fluidized bed and grows upward until it reaches the launder. While this point was not specifically addressed in evidence, from my own understanding I am not satisfied this passage discloses a froth layer. I would think a froth layer, being “bubble rich” (Napier Munn, at paragraph 58) would develop on the upper surface of a liquid, not at the interface of a teeter bed such that a layer of water would – at least initially – exist above it. This passage instead appears to disclose a layer where bubble particle aggregates are prevalent within an upward rising water phase (this seems to be consistent with the evidence of Dr Kohmuench, when discussing the HydroFloat device I refer to immediately below – see Kohmuench 2, at paragraph 16). This disclosure falls short of a froth.
Eriez in evidence further or alternatively relied upon its use of the “HydroFloat” separator as establishing that a froth layer is inherent to the teaching of Mankosa. The HydroFloat separator is a product sold by Eriez and is, Eriez submits, a commercial embodiment of the separator described in Mankosa. I refer to part of a passage I quoted earlier from General Tire:
“if carrying out the directions contained in the prior inventor's publication will inevitably result in something being made or done which, if the patentee's patent were valid, would constitute an infringement of the patentee's claim, this circumstance demonstrates that the patentee's claim has in fact been anticipated.”
To establish that a froth layer is inherent to Mankosa Eriez must establish that Mankosa provides directions which inevitably result in a froth layer. By referring to the HydroFloat separator Eriez in effect submit that, because one commercial embodiment of the Mankosa device has a froth layer, a froth layer must be an inevitable result of following the directions of Mankosa. I am not satisfied this is true. From such evidence I could only ever be satisfied that following the directions of Mankosa could result a froth layer, not that it inevitably would. In any case, I note that Eriez’s experts acknowledge that use of the HydroFloat separator does not involve a “traditional” froth layer, i.e. one of sufficient depth and stability to drain liquid and entrained particles (Kohmuench 2, at paragraph 11; Luttrell, at paragraph 23; see also Epstein, at paragraph 15). While the evidence is not direct on this point, it would seem this is because the HydroFloat separator is set up to collect water and particles from the collection launder, and not strictly froth (see Mankosa at column 1 lines 51 and 52, which state that rising water and solids flow into the launder for a hindered bed separator; see also JK-06, which at page 266 states “the HydroFloat is operated without a traditional froth, and provides a continuous overflow”).
The disclosed feed inlet
Mankosa discloses that particles enter the separator through feed inlet chamber 4, which is provided about or above the height of the teeter bed interface. According to the disclosed process higher density particles will enter the teeter bed while coarse, lower density particles will enter the teeter bed after having accumulated at the teeter bed interface (at column 5 lines 35-41). Fine, low density particles that collect at the interface are carried to the top of the separator without having entered the teeter bed. I am not satisfied the disclosed process involves the feeding of a mixture of particles in a fluid into a fluidized bed. What is disclosed is a process where a mixture of particles in a fluid are fed into a cell above the teeter bed and wherein heavier and/or coarser particles enter the bed while the less dense, finer particles (and from my understanding the fluid) do not enter the bed (see also Napier-Munn, at paragraph 64).
Settling chamber
I am not satisfied the process disclosed in Mankosa involves a settling chamber provided above the teeter bed. Mankosa describes the region above the teeter bed as a layer of particle bubble aggregates building up from the interface until the aggregates overflow into the launder. Mankosa further notes that the updraft in this region is sufficient to prevent fine, less dense particles from entering the teeter bed. These particles are instead carried to the top of the vessel. Such a region does not appear to constitute a region where non-selected particles entrained in a bubble’s wake are able to systematically fall under gravity back into the fluidized bed. Rather, the explicit teaching of Mankosa is that certain non-selected particles will not be able to fall back into the fluidized bed due to the degree of updraft.
Conclusion
Eriez have not established that any claim lacks novelty in view of Mankosa.
Inventive step
Subsection 7(2) of the Act states that an invention is taken to involve an inventive step unless it would have been obvious to a person skilled in the art in the light of the common general knowledge, considered alone or together with the prior art. A document is prior art for this purpose if "a skilled person mentioned in subsection (2) could, before the priority date of the relevant claim, be reasonably expected to have ascertained, understood, regarded [the document] as relevant" (subsection 7(3)).
The test for whether an invention is obvious is to ask whether it would have been a matter of routine to proceed to the claimed invention. In Wellcome Foundation Ltd v V.R. Laboratories (Aust.) Pty Ltd [1981] HCA 12 at [45], 148 CLR 262 at 286 Aickin J stated:
"The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not."
The problem to be solved
I have previously identified the aim of the invention to be improving the flotation of coarse particles by reducing or substantially eliminating turbulence within the cell. The problem solved may therefore be inversely stated as turbulence in prior art flotation cells negatively affecting the flotation of coarse particles.
Mankosa
Eriez relied on Mankosa for as relevant prior art for the purposes of inventive step. Newcastle did not contest that Mankosa is a document that one could reasonably expect the person skilled in the art to ascertain, understand, and regard as relevant.
Claim 1
I found above that the invention of claim 1 is distinguished from Mankosa in that it comprises a froth layer, feeding a mixture of particles in a fluid to a fluidized bed, and a settling chamber above the fluidized bed. It would seem these differences arise from the different backgrounds upon which each device has been developed. The Mankosa device seeks to improve upon pre-existing hindered bed separators. As Mankosa discloses, with hindered bed separators solids are typically introduced in the upper portion of the vessel such that fine, low density solids do not enter the bed but rather exit the cell via rising water entering the launder. The present invention seeks to improve upon existing froth flotation technologies.
Eriez have not presented evidence satisfying me that the person skilled in the art would as a matter of routine have altered the device and process disclosed in Mankosa to incorporate the identified differences. Instead, Dr Luttrell acknowledges that the position of the feed inlet and the provision of a “deep froth” layer has “merit for intellectual property protection” (Luttrell, at paragraph 23) and Professor Epstein acknowledges that the provision of a froth layer “may have an advantage over Mankosa” in preventing fine and/or low density particles entering the launder (Epstein, at paragraph 15).
Regarding the positioning the feed I am not satisfied that the person skilled in the art would necessarily find it desirable or appropriate, when separating on the basis of density, to have fine, less dense particle enter the teeter bed. Quoting column 1 line 53 to column 2 line 5 of Mankosa (my emphasis added):
Solids are typically introduced in the upper portion of the vessel and begin to settle at a rate defined by the particle size and density. The coarse, higher density particles settle against the rising flow of water and build a bed of teetering solids. This bed of high-density solids has an apparent density much higher than the teetering fluid (water). Since particle settling velocity is driven by the density difference between the solid and liquid phase, the settling velocity of the particles is reduced by the increase in apparent density of the teetering bed. As a result, the low-density component of the feed resists penetrating the bed and remains in the upper portion of the separator where it is transported to the overflow launder by the rising teeter water.
Coarse, low-density particles, however, tend to gather at the interface between the high and low density particles because the teeter water velocity is not sufficient to transport this material to the overflow launder. These particles continue to gather at the bed interface and eventually migrate into the teeter bed, thus reporting with the high-density product.”
Similarly, in JK-08 (a textbook by K. Heiskanen entitled “Particle Classification”) the following is stated (at page 150, my emphasis added):
“The teeter bed is also in effect a dense media bed. Particles having a density lower than the apparent density of the teeter bed do not enter it irrespective of their size, enabling the classification of light particles.”
Accordingly it would seem that the teeter bed conventionally plays a role in ensuring less dense particles do not form part of the tailings by ensuring those particles do not enter the bed. Altering the Mankosa device to feed them to the bed would therefore be, it seems to me, counter-intuitive.
Claims 7 and 15
Claims 7 and 15 are distinguished from the device of Mankosa in that the defined device comprises a fluidization chamber arranged to receive a feed of a mixture of particles and fluid into the lower part of the chamber, and a tailings separation means arranged to remove non-hydrophobic particles from the top of the fluidized bed.
The evidence of Dr Kohmuench is that the location of the tailings port and tailings removal constitutes merely a design choice and is therefore uninventive. I am not satisfied this is the case. Dr Kohmuench states that (Kohmuench 1, at paragraph 21):
“it is well known that particles of different density settle at different levels, i.e. heavy particles settle towards a bottom of the bed and light particles settle towards a top of the bed. Thus placement of the tailings separation means is a design choice.”

I accept it is known that particles of different density may settle toward different ends of a fluidised bed. Such is supported by JK-08 at page 149. I am not however satisfied this knowledge would lead a person skilled in the art toward altering the disclosed position of the tailings port. The clear teaching of Mankosa is that one is seeking to separate particles on the basis of actual or superficial density. In other words, that one is seeking to separate denser particles (which in Mankosa would congregate in the bottom of the teeter bed) from less dense particles (such as bubble particle aggregates which, according to Mankosa, will form a layer building upward from the interface of the teeter bed). It therefore seems counter-intuitive to place a tailings port at the top of the teeter bed where particles one desires to separate from the tailings have accumulated. Dr Kohmuench also directed me to JK-08 which demonstrates multiple methods of underflow discharge for fluidized bed separators. While multiple methods of underflow discharge are demonstrated, each appears to remove tailings from the bottom, or near the bottom, of the fluidised bed.
Professor Napier Munn notes that, in relation to the device of the present application, positioning of the tailings outlet at the top of the fluidized bed advantageously allows quicker removal of the tailings from the fluidized bed, which in turn is likely to lead to a more optimal concentrate product (at paragraph 69).
I am not satisfied it an obvious design choice to alter the position of the tailings outlet as required.
Regarding the positioning of the feed, I have noted above that I am not satisfied it would be obvious to allow fine or less dense particles to be fed into the teeter bed when separating on the basis of density as disclosed in Mankosa. As I have discussed, this would appear to be counter-intuitive for hindered bed separators.
Eriez have not established that any claim lacks an inventive step in view of Mankosa.
Manner of manufacture
Eriez submits that the invention claimed and disclosed in the application is not a manner of manufacture insofar as it relates to a combination of features involving no invention. At the hearing Eriez clarified this submission to mean that the invention claimed concerned a mere collocation of known parts.
I am satisfied that that there is a working interrelationship between, for example, the positioning of the feed inlet of claim 7 and the properties and composition of the fluidized bed. Similarly I am satisfied the existence of the fluidised bed affects the properties and composition of the froth layer, and vice versa. The relationship between these elements affects the overall selectivity and yield of desired particles. I am therefore not satisfied that the invention claimed in any claim is a mere collocation of known features.
Clarity
A claim is lacking in clarity if a third party could not ascertain whether an act would fall within the scope of the claim (Monsanto Co v Commissioner of Patents (1974) 48 ALJR 59 at 60). A lack of precise definition in claims is not fatal to their validity so long as they provide a workable standard suitable to the intended use (Minnesota Mining & Manufacturing Co v Beiersdorf (Aust) Ltd [1980] HCA 9 at [46]; [1980] HCA 9; (1980) 144 CLR 253 at 274).
Eriez submitted that several claims lacked clarity due to antecedence issues relating to certain words. I have considered the issues raised and I am satisfied that any ambiguity they may generate is resolvable though purposive construction. For example, I am satisfied a person skilled in the art would understand that “the mixed particles and fluid” defined in claim 1 is a reference to the earlier defined “mixture of particles in a fluid”. I am similarly satisfied that the person skilled in art would understand what is intended by “selected particles” and “attached selected particles” from the context in which the term is used in claim 1. Regarding claim 7, I am satisfied that reference to “the chamber” would be understood to relate to the earlier defined “fluidization chamber”. These are matters of a sort which are easily resolvable by a person skilled in the art willing to understand what is claimed. With regard to this matter, while Mr Graf provided a declaration detailing matters he considered unclear, I note that he is the patent attorney representing Eriez. Those experts being active or having a background in the field did not appear to have any trouble providing a construction to the claims (see for example JK-02, which is a novelty table completed by Dr Kohmuench and provides a feature by feature comparison of the claims against the disclosure of Mankosa).
Fair basis
In discussing the test for fair basis, the High Court in Lockwood Security Products Pty Ltd v Doric Products Pty Ltd [2004] HCA 58 at [69], 217 CLR 274 at 300 (“Lockwood v Doric”) approved of the words of Gummow J in Rehm Pty Ltd v Websters Security System (International) Pty Ltd (1988) 81 ALR 79 at 95:
“the question is whether there is a real and reasonably clear disclosure in the body of the specification of what is then claimed, so that the alleged invention as claimed is broadly, that is to say in a general sense, described in the body of the specification.”
Eriez submits that the feature “separating selected hydrophobic particles from a mixture of particles in a fluid” is not fairly based because the description does not state that only some (i.e. selected) hydrophobic particles would pass into the froth layer whereas non-selected hydrophobic particles would not. This matter is resolved by purposive construction of the claimed feature. The person skilled in the art would understand that hydrophobic particles are being selected from a mixture of hydrophobic and hydrophilic particles for removal by attachment to bubbles. The claim does not require that hydrophobic particles are to be selected from other hydrophobic particles. Based on the evidence I note that no expert working in the field construed claim 7 to require that hydrophobic particles are selected from other hydrophobic particles (see for example JK-02, at page 5).
Full description
Eriez submits that description lacks sufficiency in that it does not detail how the disclosed froth layer would be defined, created or controlled. Eriez have not established this to be a matter a person skilled in the art would have trouble determining for him or herself. The evidence instead establishes that flotation processes involving a froth layer are well established in the art (Kohmuench 1, at paragraph 18; Napier-Munn, at paragraph 31; Luttrell, at paragraph 23; Epstein, at paragraph 15). Eriez have not established that any claim lacks full description.
Conclusion
The opposition has not succeeded on any ground. Subject to an appeal against this decision the application is to proceed to grant.
Costs
Generally costs should follow the event. I see no reason to depart from this approach in the present circumstances. I will award costs according to Schedule 8 against Eriez.
Rhys Munzel
Delegate of the Commissioner of Patents