DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
Claims 27 and 38 and claims 39-53 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected Species I-B and Group II respectively, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 07/15/2026.
Applicant’s election without traverse of Group I and Species I-A in the reply filed on 07/15/2026 is acknowledged.
Response to Amendment
The amendment filed 07/15/2026 has been entered. Claim(s) 1-54 is/are pending in this application, of which claims 1-26, 28-37, and 54 are examined herein. Claim(s) 27 and 38-53 is/are withdrawn. Claim(s) 54 is/are new.
Claim Objections
Claims 10 and 26 are objected to because of the following informalities:
Claim 10: “volatile reagent” should read “volatile leaching reagent” to match the term used in parent claim 9
Claim 26: “heap heated” in line 1 should read “heap is heated”
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 54 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 54 recites “wherein the sulphide ore is ultramafic”. The instant specification discloses ultramafic ores may be leached by the process (pg. 7 paragraph 6) including nickel ultramafic ores (Example 3, pg. 8 paragraph 8, Fig. 4), and that separately sulphide ores may be leached by the process (pg. 3 paragraphs 1-2, pg. 6 paragraphs 1 and 5-6, Example 2). The instant specification however does not disclose an ultramafic sulphide ore, let alone that such is leached by the process, and therefore does not describe the claimed invention in a manner understandable to a person of ordinary skill in the art in a way that shows that the inventor invented the claimed invention at the time of filing. Correction is required.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-26, 28-37, and 54 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The term “substantially impermeable” in claim 1 is a relative term which renders the claim indefinite. The term “substantially impermeable” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention, making unclear how impermeable the heap coating must be to gas and liquid.
Claim 8 recites the limitation "with subsequent purging of warm gas" in lines 2-3. The limitation is indefinite as it is unclear what step the warm gas purging is subsequent to.
Claim 9 recites the limitation "the leaching reagent" in line 1. There is insufficient antecedent basis for this limitation in the claim.
Claim 11 recites the limitation “wherein ore" in line 1. The lack of an article preceding “ore” renders the claim indefinite as it is unclear if claim 11 further limits the ore of the heap in parent claim 1, or instead limits another ore unrelated to the crushed ore deposited and stacked on the impermeable pad of claim 1.
Claim 11 recites the limitation "the valuable metals of copper, gold, nickel, uranium, and zinc" in line 2. The limitation is indefinite as it is unclear whether “valuable metals” merely further describes the Applicant’s view of copper, gold, nickel, uranium, and zinc as having value, or if “valuable metals” further limits copper, gold, nickel, uranium, and zinc to only “valuable metal” versions of those metals (e.g., reduced metal, in certain ionic forms, etc.).
Claim 12 recites the limitation "wherein sulphide concentrates have been mixed with the ore”" in lines 1-2. The limitation is indefinite as it is unclear if the claim requires that the sulphide concentrates are presently mixed with the ore (i.e., within the context of their use in the method), or if they merely were at some point mixed with the ore, but need not be mixed with the ore in their use in the claimed method.
Claim 12 recites the limitation "the valuable metals of copper, gold, nickel, uranium, and zinc" in lines 2-3. The limitation is indefinite as it is unclear whether “valuable metals” merely further describes the Applicant’s view of copper, gold, nickel, uranium, and zinc as having value, or if “valuable metals” further limits copper, gold, nickel, uranium, and zinc to only “valuable metal” versions of those metals (e.g., reduced metal, in certain ionic forms, etc.).
Claim 13 recites the limitation "different valuable components" in line 2. The limitation is indefinite as it is unclear whether “different” requires that multiple distinct components be simultaneously recovered by the sequential leaching, or that one or more product(s) are recovered from the first leach in the sequence and one ore more other product(s) are recovered from the second leach in the sequence.
Claim 13 recites the limitation “different valuable components”. The term “different valuable components” is not defined by the instant specification nor does the term have an established meaning in the art, thus the term is interpreted according to its plain meaning, however “different valuable components” is ambiguous as it is unclear what type or manner of products the limitation actually refers to (e.g., metals, non-metals, organic compounds, combinations of metals and non-metals, etc.). Correction is required.
The term “high levels” in claim 18 is a relative term which renders the claim indefinite. The term “high levels” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention, making unclear how much acid consuming gangue is present for the leach to be conducted under basic conditions.
The term “difficult to maintain a water balance with rainfall or evaporation” in claim 28 is a relative term which renders the claim indefinite. The term “difficult to maintain” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention, making unclear what degree the water balance must be difficult to balance to comprise a climatic condition claimed.
Claim 29 recites the limitation "dynamic in nature" in line 1. The limitation is indefinite as it is unclear what attribute or quality of the heap is dynamic (e.g., angle of repose of ore, porosity of ore, density of ore), making unclear what precondition further limits the heap to have a fixed structure to contain the ore.
Claim 30 recites the limitation "including multiple sealed heaps" in line 1. The limitation is indefinite as it is unclear what element of parent claim 1 is further limited to comprise multiple sealed heaps.
Claim 31 recites the limitation "between cells within a heap" in line 2. The limitation is indefinite as it is unclear how reagents are transferred between cells within a heap, as parent claim 30 only recites each heap containing a cell (i.e., 1 cell), making unclear if more than one cell may be within a heap, or if reagents are only transferred between the multiple sealed heaps, where each sealed heap only comprises a single cell.
Claim 36 recites the limitation "the crushed rock" in lines 1-2. There is insufficient antecedent basis for this limitation in the claim.
Claim 36 recites the limitation "the contained values" in lines 2-3. There is insufficient antecedent basis for this limitation in the claim.
Claim 37 recites the limitation "the leaching cycle" in line 2. There is insufficient antecedent basis for this limitation in the claim.
Claim 37 recites the limitation "tenor" in line 3. The limitation is indefinite as it is unclear what “tenor” refers to in this context, as the pregnant liquor does not relate to a vocal range or is itself something that could be considered to have a general meaning, character, or usual pattern.
Claim 37 recites the limitation "the tenor of the pregnant liquor" in line 3. There is insufficient antecedent basis for this limitation in the claim.
Claims dependent upon claims rejected above, either directly or indirectly, are likewise rejected under this statute.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1-6, 8-12, 14-17, and 23-26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile et al. (US 20130247719 A1, cited in Office Action dated 05/15/2026) in view of Urie et al. (US 20120118110 A1, cited in IDS filed 04/25/2024).
Regarding claim 1, Esdaile teaches a method of recovering metal values from ore in a heap leach process (Abstract, [0010]), depositing and stacking crushed ore to form a heap [0066], and enclosing the heap with a substantially impermeable coating to both gas and liquid to form a sealed heap [0010, 0014]. Esdaile teaches irrigating the sealed heap with a leachant added inside the top of the heap [0066], allowing the leachant to percolate through the heap and removing leachant at the base of the heap (Fig. 1, [0066]), to a collection pond [0125-0127], from which one of ordinary skill would recognize the leachant would be subjected to subsequent processing. Esdaile teaches adding air (i.e., an oxygen containing gas) to the sealed heap [0047].
Esdaile does not teach depositing and stacking the crushed ore on a pad.
Urie teaches methods and systems for leaching a metal-bearing ore for the recovery of a metal value (title), by heap leaching (abstract, [0002]). Esdaile teaches ore is placed on a lined leach pad or impermeable geologic formation (i.e., depositing and stacking the crushed ore on an impermeable pad) [0058].
Because Esdaile is silent with respect to what the ore should be stacked upon to form the heap, in order to carry out the invention of Esdaile one of ordinary skill in the art would necessarily look to the art for a reference teaching a suitable component to stack ore upon for use within the process of Esdaile, such as that of an impermeable pad as taught by Urie. As Esdaile and Urie both relate to leaching of ores in heaps, one of ordinary skill would be motivated to use the impermeable pad of Urie.
Regarding claims 2-4, Esdaile teaches that air flows into the heap under natural convection from outside the heap (i.e., the atmosphere) (Fig. 1, [0041, 0085, 0122]), therefore the gas pressure within the heap would be maintained at atmospheric pressure (about 1 atmosphere) when aeration is performed under natural convection from outside the heap, which is within the claimed ranges.
Regarding claim 5, Esdaile teaches wherein the ore is sulphidic material [0002-0006], and that the ore oxidizes under aerobic conditions as an exothermic process, generating significant heat (i.e., wherein the temperature within the heap is elevated by the oxidation of a contained sulphide) [0109].
Esdaile does not teach an operating temperature of the heap.
Urie teaches bacteria can be added to the agglomerated ore to improve efficiency of heap leaching operations [0004], and enable significant enhancement in metal value yield as compared to conventional metal value recovery methods and systems [0018]. Urie teaches the bacteria may be from any of Groups A, B, C, and D, where the bacteria are used at temperatures of at or below 40 °C for Groups A and B, at or below about 60 °C for Group C, and about 60-80 °C for Group D [0040], which are within or overlap the claimed temperature range.
Urie teaches temperatures of at or below 40 °C and at or below 60 °C. This overlaps the claimed range of from ambient temperature to 100 °C. The overlap between the ranges taught in the prior art and recited in the claims creates a prima facie case of obviousness because the prior art indicates substantial utility over the entire range disclosed therein, including that portion of the range which also falls within the claimed range. See MPEP § 2144.05(I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added bacteria to the heap leach as taught by Urie to the method of heap leaching of Esdaile as doing so would improve efficiency of heap leaching operations, and enable significant enhancement in metal value yield as compared to conventional metal value recovery method as taught by Urie.
Regarding claim 6, Urie teaches temperatures of about 60-80 °C when using bacteria from Group D [0040], which is within the claimed range.
Regarding claim 8, Esdaile teaches the system controls air flow in the heap [0014, 0041], and that the ore oxidizes under aerobic conditions as an exothermic process, generating significant heat (i.e., wherein the temperature within the heap is elevated by the oxidation of a contained sulphide) [0109], therefore the temperature within the heap is controlled by the amount of air added together with the oxygen. Esdaile teaches subsequent purging of gas via vents 23 [0127], where because exothermic heating occurs in the heap [0109], the gas would comprise warm gas relative to e.g., the gas prior to the heating.
Regarding claims 9-10, Esdaile teaches the leaching proceeds by oxidation with oxygen (wherein the leaching reagent includes or comprises a volatile leaching reagent, wherein the volatile reagent is oxygen) [0109].
Regarding claim 11, Esdaile teaches wherein the method relates to leaching valuable metal [0001], where the ore is a sulphide ore containing copper [0003].
Regarding claim 12, Esdaile teaches the method relates particularly, although by no means exclusively, to leaching a material in the form of a sulphidic ore containing a valuable metal [0002], however Esdaile does not teach wherein sulphide concentrates have been mixed with the ore.
Urie teaches metal-bearing material in the heap may be copper sulfide ore and/or copper sulfide concentrates (i.e., wherein sulphide concentrates have been mixed with the ore) [0025, 0071], for example chalcopyrite (CuFeS2) and/or bornite (Cu5FeS4) (i.e., contain one or more of iron and the valuable metal of copper) [0071].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added a sulphide concentrate as taught by Urie to the method of Esdaile as doing so would provide additional material from which valuable copper could be leached.
Regarding claim 14, Esdaile teaches wherein the ore is crushed [0111].
Esdaile does not teach wherein the ore is fully or partially agglomerated prior to stacking.
Urie teaches agglomeration of the ore in the heap prior to stacking (i.e., fully or partially agglomerated prior to stacking) [0027, 0032], where agglomeration allows for optimal economic recovery of the contained metal values [0027].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have agglomerated the ore stacked on the heap leach as taught by Urie in the method of Esdaile, as doing so allow for optimal economic recovery of contained metal values as taught by Urie.
Regarding claim 15-17, Esdaile teaches wherein the sealed heap is utilized to leach primary copper ores containing chalcopyrite [0004]. Esdaile does not teach the temperature of the leaching.
Urie teaches bacteria can be added to the agglomerated ore to improve efficiency of heap leaching operations [0004], and enable significant enhancement in metal value yield as compared to conventional metal value recovery methods and systems [0018]. Urie teaches the bacteria may be from any of Groups A, B, C, and D, where the bacteria are used at temperatures of about 60-80 °C for Group D [0040], which is within the claimed ranges of claims 15 and 16.
Urie teaches temperatures of at or below 40 °C and at or below 60 °C. This overlaps the claimed range of about 70 °C of claim 17. The overlap between the ranges taught in the prior art and recited in the claims creates a prima facie case of obviousness because the prior art indicates substantial utility over the entire range disclosed therein, including that portion of the range which also falls within the claimed range. See MPEP § 2144.05(I).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added bacteria to the heap leach as taught by Urie to the method of heap leaching of Esdaile as doing so would improve efficiency of heap leaching operations, and enable significant enhancement in metal value yield as compared to conventional metal value recovery method as taught by Urie.
Regarding claims 23-24, Esdaile teaches the heap may be any suitable size and shape [0017], but is silent to an appropriate height of the heap.
Urie teaches the height of the heap may range from about 5 to about 100 meters [0058].
Because Esdaile is silent with respect to a suitable height of the heap, in order to carry out the invention of Esdaile one of ordinary skill in the art would necessarily look to the art for a reference teaching heights of the ore heap suitable for use within the process of Esdaile, such as that of about 5-100 meters as taught by Urie. As Esdaile and Urie both relate to heap leaching of ores, one of ordinary skill would be motivated to use the heights of the heap of Urie.
Regarding claim 25, Esdaile teaches wherein after leaching the material in an existing heap to a threshold level (i.e., completion of the heap leach), forming a second lift of material on the existing heap [0090], where the material from the first lift of the sealed heap would comprise stored residue.
Regarding claim 26, Esdaile does not teach wherein the sealed heap heated using external heating.
Urie teaches bacteria can be added to the agglomerated ore to improve efficiency of heap leaching operations [0004], and enable significant enhancement in metal value yield as compared to conventional metal value recovery methods and systems [0018]. Urie teaches the bacteria is produced in bioreactor 310 [0048-0050], and the bacteria is added to the agglomerated ore as part of effluent solution 212 ([0048], Fig. 2). Urie teaches the bioreactor 310 uses a heat exchanger 330 to supply hot liquid to the bioreactor where bacteria is cultured to encourage growth of the bacteria (Fig. 2, [0048, 0054]), which would transfer heat to the heap when the bacteria is added to the agglomerates added to the heap (i.e., wherein the sealed heap heated using external heating).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added bacteria using a bioreactor supplied with heat external to the heap in the heap leach as taught by Urie to the method of heap leaching of Esdaile as doing so would improve efficiency of heap leaching operations, and enable significant enhancement in metal value yield as compared to conventional metal value recovery method as taught by Urie.
Claim(s) 7, 30-35, and 37 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile in view of Urie as applied to claim 1 above, further in view of Johnson (US 4526615 A, cited in IDS filed 04/25/2024).
Regarding claim 7, Esdaile in view of Urie does not teach wherein the temperature within the heap is controlled by external heat exchange to set the temperature of the leachant being irrigated in the sealed heap.
Johnson teaches a cellular heap leach process and apparatus (Title), where metal values are leached from ore by heap leaching on an impermeable pad (Abstract), thus Johnson and Esdaile in view of Urie are analogous to the instant application as both are directed to heap leaching of metals from ore on impermeable pads. Johnson teaches wherein the leach solution is heated prior to introducing to heap (i.e., external heat exchange), which overcomes the problem of freezing/reduction of reaction rates (Col. 11 lines 16-21), where heating the incoming leach solution would increase the temperature within the heap (i.e., temperature within the heap is controlled by external heat exchange to set the temperature of the leachant being irrigated in the sealed heap).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have heated the leach solution incoming to the heap of Esdaile in view of Urie as taught by Johnson as doing so would overcome problems of freezing of leach solution and reduction of reaction rates.
Regarding claim 30, Esdaile in view of Urie does not teach including multiple sealed heaps with each heap comprising a cell.
Johnson teaches a cellular heap leach process and apparatus (Title), where metal values are leached from ore by heap leaching on an impermeable pad (Abstract), thus Johnson and Esdaile in view of Urie are analogous to the instant application as both are directed to heap leaching of metals from ore on impermeable pads. Johnson teaches its heap is constructed with a plurality of cellular heaps loaded on a single pad and contiguous to each other (i.e., including multiple sealed heaps with each heap comprising a cell) (Abstract, Col. 4 lines 15-18). Johnson teaches the cellular heap arrangement allows ore to be left in place while providing for leaching of additional ore (Col. 4 lines 32-34), and allows administering leach solution selectively to the various cells, and countercurrent leaching of the cells to obtain an effluent solution having a relatively constant and high metal value concentration (Col. 5 lines 15-23).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a cellular heap as taught by Johnson as the heap of Esdaile in view of Urie, as doing so would allow for ore to be left in place while providing for leaching of additional ore, selective administering of leach solution to the various cells, and countercurrent leaching through the cells which produces effluent solution with constant and high metal value concentration.
Regarding claim 31, Johnson teaches leach solution from the various cells may be recirculated (Col. 6 lines 58-60), such as recirculation of 3rd leach stage solution through cells 101-104c and 121b-124b (i.e., wherein reagents are transferred within and between cells within a heap or heaps) (Col. 14 lines 9-13). Johnson teaches the amount of recirculation through each cell may be controlled to ensure uniform leaching throughout heap (i.e., reagents are transferred to control leaching conditions). (Col. 13 lines 26-29), where the recirculation minimizes reagent use (i.e., minimize losses of reagent) (Col. 8 lines 64-67).
Regarding claim 32, Johnson teaches the intermixing of return solutions (Col. 19 lines 31-36), and that solution cools at the surface of the heaps (Col. 12 lines 59-61), therefore upon leachant entering a cell, there is transfer of heat between cells as recirculated solution is taking heat from downstream cells that was present in cells upstream of the recirculation (i.e., wherein leachant is transferred within and between the cells to transfer heat between cells).
Regarding claim 33, Esdaile teaches a combination of aeration system and air impermeable barrier which controls oxygen levels in the heap [0014], which results in minimal ingress of oxygen [0109], and controls oxygen levels to comprise aerobic/anerobic conditions [0121], where control of the oxygen levels in the heap would include controlling to e.g., optimize efficient use of oxygen. Johnson teaches the heap to comprise a cellular heap (Abstract, Col. 4 lines 15-18)), but that the cells may not have a physical barrier between adjacent cells (Col. 4 lines 27-28, Fig. 1), therefore in combining Esdaile which transfers gas into the heap, and Johnson, which teaches cells in the heap which are not disclosed to obstruct flow of gas within or between cells, Esdaile in view of Johnson suggests wherein gas is transferred within and between cells to control the oxygen content of the heap as claimed.
Regarding claim 34, Johnson teaches intermixing of recirculating return solutions to the heap (wherein the leachant is transferred between cells) (Col. 19 lines 8-25). Johnson teaches it is very beneficial to apply a slow percolation rate of sprinkling/intermittent ponding to apply the leach solution to relatively unleached cells (i.e., varying the irrigation rate of the heap according to the extent of leaching) Col. 15 lines 4-12), which results in extremely high metal value concentration (Col. 15 lines 12-15).
Regarding claim 35, Esdaile teaches the method may comprise forming a second lift on top of the heap [0079], where an air impermeable barrier (i.e., the impermeable coating) is on the top of the heap [0015]. Esdaile in view of Urie does not teach wherein the sealed heap is further insulated with a layer of sand on top of the impermeable coating
Johnson teaches a cellular heap leach process and apparatus (Title), where metal values are leached from ore by heap leaching on an impermeable pad (Abstract), thus Johnson and Esdaile in view of Urie are analogous to the instant application as both are directed to heap leaching of metals from ore on impermeable pads. Johnson teaches wherein a permeable sand layer 74 is placed between upper 64b and lower 64a cells (analogous to first and second lifts of a heap) (Col. 10 lines 18-32, Fig. 6) above an impermeable barrier 68 (analogous to the impermeable coating) (Fig. 6, Col. 10 lines 28-32). Johnson teaches the layer of sand allows for even collection of leach solution from the overlying lift 64b (Col. 10 lines 29-32).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added a sand layer above the impermeable coating as taught by Johnson in the method of heap leaching of Esdaile in view of Urie, as doing so would allow for even collection of leach solution in the overlying second heap.
Regarding claim 37, Esdaile in view of Urie does not teach wherein the leachant irrigation rate is adjusted according to the extent of leaching.
Johnson teaches a cellular heap leach process and apparatus (Title), where metal values are leached from ore by heap leaching on an impermeable pad (Abstract), thus Johnson and Esdaile in view of Urie are analogous to the instant application as both are directed to heap leaching of metals from ore on impermeable pads. Johnson teaches its heap is constructed with a plurality of cellular heaps loaded on a single pad and contiguous to each other (i.e., including multiple sealed heaps with each heap comprising a cell) (Abstract, Col. 4 lines 15-18). Johnson teaches the cellular heap arrangement allows ore to be left in place while providing for leaching of additional ore (Col. 4 lines 32-34), and allows administering leach solution selectively to the various cells, and countercurrent leaching of the cells to obtain an effluent solution having a relatively constant and high metal value concentration (Col. 5 lines 15-23). Johnson teaches intermixing of recirculating return solutions to the heap (Col. 19 lines 8-25). Johnson teaches it is very beneficial to apply a slow percolation rate of sprinkling/intermittent ponding to apply the leach solution to relatively unleached cells (i.e., wherein the leachant irrigation rate is adjusted according to the extent of leaching) Col. 15 lines 4-12), which results in extremely high metal value concentration (i.e., to rapidly recover values early in the leaching cycle) (Col. 15 lines 12-15), where as the concentration of the metal values in the pregnant leach solution are increased, Johnson teaches increasing the tenor of the pregnant liquor late in the cycle as best can be examined in view of the rejection of claim 37 under 35 USC 112(b) above.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used a cellular heap as taught by Johnson as the heap of Esdaile in view of Urie, as doing so would allow for ore to be left in place while providing for leaching of additional ore, selective administering of leach solution to the various cells, and countercurrent leaching through the cells which produces effluent solution with constant and high metal value concentration.
It would have been further obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have applied a slow percolation rate on relatively unleached cells as taught by Johnson as doing so would increase the metal value concentration in the recovered leach solution.
Claim(s) 13 and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile in view of Urie as applied to claim 1 above, further in view of Ke (CN 113512647 A, original document and machine translation supplied herein).
Regarding claim 13, Esdaile in view of Urie teaches that sulphide oxidation occurs at about pH 1.2.-2 (i.e., the sealed heap is utilized to leach ores in acid) (Urie: [0042]), where copper, nickel, zinc, silver, gold, germanium, lead, arsenic, antimony, chromium, molybdenum, rhenium, tungsten, iron, ruthenium, osmium, cobalt, rhodium, iridium, palladium, platinum, uranium, and/or rare earth metals are recovered (Esdaile: [0002], Urie: [0022-0023]). Esdaile in view of Urie does not teach leaching under sequential leaching further under basic conditions.
Ke teaches an enhanced leaching method for copper ore (Title), where copper ore is heap leached [n0031], and the ore is primarily in sulfide form [n0002] thus Ke and Esdaile in view of Urie are analogous as both are directed to heap leaching of sulfide copper ores. Ke teaches the leaching may use either acidic or alkaline leaching agent [n0031], where alkaline leaching has a wider range of applications as it is not affected by gangue minerals, with good leaching effect on copper minerals containing iron-bearing and siliceous gangues, but with lower leaching rates than acid leaching [n0014].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have additionally leached the sulfide copper ore of Esdaile in view of Urie using an alkaline leach as taught by Ke, as doing so would recover copper with good leaching effect without being negatively affected by gangue minerals. Therefore, Esdaile in view of Urie and Ke teaches the sealed heap is utilised to sequentially leach ores in basic and then acid conditions, where as copper is recovered in the basic leaching step, and copper and other metals may be recovered in the acid leaching, the sequential leaching recovers different valuable components from the ore.
Regarding claim 18, Esdaile in view of Urie does not teach wherein the ore contains high levels of acid consuming gangue. Ke teaches an enhanced leaching method for copper ore (Title), where copper ore is heap leached [n0031], and the ore is primarily in sulfide form [n0002] thus Ke and Esdaile in view of Urie are analogous as both are directed to heap leaching of sulfide copper ores. Ke teaches almost all copper ores comprise gangue minerals in some form, which consume large amounts of acid and is uneconomical when extracting from alkaline gangue materials (i.e., wherein the ore contains high levels of acid consuming gangue) [n0005, n0012]. Ke teaches alkaline leaching (i.e., leach conducted under basic conditions) methods have a wider range of applications as they are not affected by gangue minerals, with good leaching effect on copper minerals containing iron-bearing and siliceous gangues [n0014].
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used alkaline leaching as taught by Ke for the heap leaching of ore of Esdaile as doing so would have a wider range of applications as they are not affected by gangue minerals, with good leaching effect on copper minerals containing iron-bearing and siliceous gangues.
Claim(s) 19-22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile in view of Urie as applied to claim 1 above, further in view of Dhawan et al. (“Crushed ore agglomeration and its control for heap leach operations”, supplied with IDS filed 04/25/2024).
Regarding claims 19-22, Esdaile teaches wherein the crushed ore is solid particles, as Esdaile teaches crushing and screening the ore which can only be performed on a solid [0111]. Esdaile does not teach a particle size of the ore.
Dhawan discusses crushed ore agglomeration and control of agglomeration for heap leach operations (Title), where crushed ore agglomeration is used to ensure better heap performance (Abstract), overcome percolation problems which cause low metal extraction due to solution channeling or development of impermeable zones within the heap (1. Introduction paragraph 1-3). Dhawan teaches a wide feed size distribution is not ideal for high quality agglomerates (1. Introduction paragraph 4), where particle sizes of the crushed ore in the heap include those of less than 2 mm (9.1. Particle Size paragraph 1).
Because Esdaile is silent with respect to a suitable particle size of crushed ore, in order to carry out the invention of Esdaile one of ordinary skill in the art would necessarily look to the art for a reference teaching crushed ore particle sizes suitable for use within the process of Esdaile, such as that of less than 2 mm as taught by Dhawan. As Esdaile and Dhawan both relate to heap leaching of crushed ores, one of ordinary skill would be motivated to use the particle sizes of crushed ore of Dhawan.
Claim(s) 28 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile in view of Urie as applied to claim 1 above, further in view of Urbina (AU 2016432918 A1, supplied herein).
Regarding claim 28, Esdaile teaches wherein a sealed heap is utilized [0010, 0014], but does not teach utilizing the sealed heap to leach ores under climatic conditions in which it is difficult to maintain a water balance with rainfall or evaporation that occurs with an open heap.
Urbina teaches a cover for covering surfaces (Title), such as in mining using leaching to recover minerals from crushed material in a pile (i.e., heap leaching) (pg. 1 paragraphs 2-4), where the cover controls surfaces of a heap that otherwise allow air, gas, water, solutions, and fluid flow (pg. 4 paragraphs 1-5), thus Urbina and Esdaile are analogous to the instant application as both are directed to sealing of heap leaching heaps. Urbina teaches covering a heap leach process with surface covers helps prevent evaporation and wind action that affect leaching from climatic conditions, and reduce the water amount used (pg. 2 paragraphs 1-3, pg. 10 paragraph 4), where evaporation further results in heat loss from the heap and produces a large water amount necessary to carry out the leaching process (pg. 2 paragraph 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used the method of Esdaile utilizing a sealed in climatic conditions where evaporation would otherwise be an issue which causes a large water amount necessary to carry out leaching (i.e., climatic conditions in which it is difficult to maintain a water balance with rainfall or evaporation that occurs with an open heap) as sealed heaps are less affected by evaporation and heat loss as taught by Urbina.
Claim(s) 29 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile in view of Urie as applied to claim 1 above, further in view of Thenepalli et al. (“A Brief Note on the Heap Leaching Technologies for the Recovery of Valuable Metals”, supplied with IDS filed 04/25/2024).
Esdaile in view of Urie teaches wherein the sealed heap uses an impermeable pad and an impermeable coating (i.e., a fixed structure) to contain the crushed ore (Esdaile: [0010, 0014], Urie: [0058]).
Esdaile in view of Urie does not teach wherein the sealed heap is dynamic in nature, where the crushed ore is then removed from the structure when it has been leached, and replaced with another batch of ore.
Thenepalli discusses heap leaching to recover metals such as copper (Abstract), thus Thenepalli and Esdaile are analogous to the instant application as both are directed to heap leaching to recover metals such as copper. Thenepalli teaches heap leaches may use an on-off pad, which allows for spent leached ore to be removed from a heap and replaced with fresh ore (i.e., wherein the sealed heap is dynamic in nature, where the crushed ore is then removed from the structure when it has been leached and replaced with another batch of ore) (pg. 4 paragraph 3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used an on-off pad according to Thenepalli as the impermeable pad used by Esdaile and to remove spent ore and replace it with fresh ore as taught by Thenepalli as doing so would have been recognized by one of ordinary skill in the art to continually leach metal from the heap by adding additional metal to the heap in the form of fresh ore.
Claim(s) 36 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile in view of Urie as applied to claim 1 above, further in view of Mwase et al. (“Assessing a two-stage heap leaching process for Platreef flotation concentrate”, supplied herein).
Esdaile teaches that sulphidic materials such as sulphidic iron and/or copper-containing ores under aerobic conditions undergo an exothermal process during heap leaching [0109], however Esdaile in view of Urie does not teach wherein flotation concentrate is mixed with the crushed rock and leached in the sealed heap.
Mwase discusses a heap leaching process for flotation concentrate (Title, abstract), the flotation concentrate comprising iron and copper as well as sulphur (Table 2), thus Mwase and Esdaile are analogous as both are directed to heap leaching of materials comprising iron, copper, and sulphur. Mwase teaches metals such as copper, nickel, cobalt, palladium, gold, and platinum may be recovered from leaching the concentrate (Abstract).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have added flotation concentrate as taught by Mwase to the method of heap leaching of Esdaile in view of Urie as doing so would recover copper, nickel, cobalt, palladium, gold, and platinum from a further material. Therefore, Esdaile in view of Urie and Mwase teaches wherein flotation concentrate is mixed with the crushed rock and leached in the sealed heap, dissolving the contained values as best can be examined in view of the rejection of claim 36 under 35 USC 112(b) above. Further, as Mwase teaches the flotation concentrate to be a sulphidic iron and copper containing composition, and Esdaile teaches that sulphidic materials such as sulphidic iron and/or copper-containing ores under aerobic conditions undergo an exothermal process during heap leaching [0109], adding flotation concentrate according to Mwase to the heap would provide additional heat during leaching.
Claim(s) 54 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esdaile in view of Urie as applied to claim 11 above, further in view of Schulz et al. (“Occurrence Model for Magmatic Sulfide-Rich Nickel Copper-(Platinum-Group Element) Deposits Related to Mafic and Ultramafic Dike-Sill Complexes”, supplied herein).
Esdaile teaches leaching ores comprising copper sulphides [0003] such as chalcopyrite, however Esdaile in view of Urie does not teach wherein the sulphide ore is ultramafic.
Schulz discusses magmatic sulfide deposits containing nickel and copper (1. Introduction paragraph 1), where deposits of magmatic Ni-Cu sulfides occur with ultramafic bodies in diverse geologic settings (1. Introduction paragraph 2), with such deposits comprising major Ni-Cu sulfide deposits (1. Introduction paragraph 2), and include materials such as chalcopyrite (1. Introduction paragraph 3).
Because Esdaile is silent with respect to what all forms or sources of chalcopyrite may be used for the process, in order to carry out the invention of Esdaile one of ordinary skill in the art would necessarily look to the art for a reference teaching sources of chalcopyrite suitable for use within the process of Esdaile, such as that of ultramafic chalcopyrite ore as taught by Schulz. As Esdaile and Schulz both relate to copper sulfide ores including chalcopyrite, one of ordinary skill would be motivated to use the ultramafic copper sulphide ore according to Schulz.
Conclusion
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/NIKOLAS TAKUYA PULLEN/Examiner, Art Unit 1733
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