Patent Application
20240327312
The present application derives its priority from Australian provisional application no. AU2022903765, filed on 9 Dec. 2022, the entire contents of which is incorporated herein by cross-reference in its entirety.
The invention relates to explosive formulations for use in reactive ground, and methods and compositions for loading blast holes in reactive ground with such explosive formulations. However, it will be appreciated that the invention is not limited to this particular field of use.
The following discussion of the prior art is provided to place the invention in an appropriate technical context and enable the advantages of it to be more fully understood. It should be appreciated, however, that any discussion of the prior art throughout the specification should not be considered as an express or implied admission that such prior art is widely known or forms part of the common general knowledge in the field.
The presence of oxidisable materials that release heat (i.e. are exothermic) upon reaction with explosives, such as ammonium nitrate (AN) compositions, can result in premature detonation of the explosive, with potentially catastrophic consequences. Accordingly, the formulation of bulk explosive products, particularly for use at higher temperatures (e.g. over 50° C., 100° C., or 150° C.) in ground (e.g. sulphidic ground) that can be reactive with such products (e.g. ammonium nitrate-based explosive products) can be challenging.
There have been a number of premature detonation events at mine sites throughout the world in which explosives have reacted with reactive ground (containing sulfides). For example, in the 1960s at a mine in Mount Isa in Australia, holes in the ore body (a reactive ground) became incandescent on contact with ammonium nitrate explosive compositions, resulting in premature detonations. Similarly, at a mine in Collinsville, Australia, in 1998, a hole in reactive ground that had been loaded with an ammonium nitrate-containing explosive detonated prematurely. Further, at the Black Star mine in Mount Isa in Australia in 2005, there was a premature detonation event caused by the reaction of an explosive with a hot reactive ground.
Standard inhibitors known in the art to prevent premature detonation of explosive compositions can generally be less effective at higher temperatures, or may be required in such high quantities to be effective in preventing premature detonation in reactive ground, optionally in reactive high temperature ground, that they can render the explosive unable to be detonated using standard detonation means.
Further, explosives per se generally can be more sensitive to initiation at higher temperatures, and as such can intrinsically be prone to premature detonation if used at high temperatures. For example, AN, when pure, intrinsically decomposes (and can detonate) at around its melting point (169.6° C.).
Accordingly, there is a need for new explosive formulations for use in reactive ground. There is also a need for new methods and compositions for safely loading blast holes in reactive ground with explosives.
It is an object of the present invention to overcome or ameliorate one or more the disadvantages of the prior art, or at least to provide a useful alternative.
The inventors of the present application postulate that explosive formulations comprising multiple components can be used to separate in time the oxidation of sulphides and/or other oxidisable compounds in a blast hole drilled into reactive ground from the presence in the blast hole of the explosive product per se, thereby preventing or at least ameliorating the risk of premature detonation of the explosive product.
In a first aspect of the invention there is provided an explosive formulation, comprising: a treatment component, comprising an oxidant; and a blasting component, comprising an explosive.
The following options may be used in conjunction with the first aspect, either individually or in any combination.
In certain embodiments of the first aspect of the invention, the oxidant of the treatment component is selected from the group consisting of sodium hypochlorite, sodium percarbonate, and/or hydrogen peroxide.
In certain embodiments of the first aspect of the invention, the explosive of the blasting component comprises a nitrate, optionally ammonium nitrate.
In certain embodiments of the first aspect of the invention, the treatment component and the blasting component of the explosive formulation are suitable to be applied sequentially to a blast hole.
In certain embodiments, the oxidant of the treatment component of the explosive formulation of the first aspect of the invention may be present in the treatment component in a concentration of from about 0.01 wt. % to about 32 wt. %, or from about 0.028 wt. % to about 32 wt. %, about 0.046 wt. % to about 32 wt. %, about 0.064 wt. % to about 32 wt. %, about 0.082 wt. % to about 32 wt. %, about 0.1 wt. % to about 32 wt. %, about 2.1 wt. % to about 32 wt. %, about 4.1 wt. % to about 32 wt. %, about 6.1 wt. % to about 32 wt. %, about 8.1 wt. % to about 32 wt. %, about 10 wt. % to about 32 wt. %, about 12 wt. % to about 32 wt. %, about 14 wt. % to about 32 wt. %, about 16 wt. % to about 32 wt. %, about 18 wt. % to about 32 wt. %, about 20 wt. % to about 32 wt. %, about 0.01 wt. % to about 29 wt. %, about 0.01 wt. % to about 26 wt. %, about 0.01 wt. % to about 23 wt. %, about 0.01 wt. % to about 20 wt. %, about 0.1 wt. % to about 20 wt. %, about 4.1 wt. % to about 20 wt. %, about 8.1 wt. % to about 20 wt. %, about 12 wt. % to about 20 wt. %, about 16 wt. % to about 20 wt. %, about 0.1 wt. % to about 16 wt. %, about 0.1 wt. % to about 12 wt. %, about 0.1 wt. % to about 8.1 wt. %, or about 0.1 wt. % to about 4.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 2.1 wt. %, 4.1 wt. %, 6.1 wt. %, or 8.1 wt. %. It may be less than or equal to about 32 wt. %, 29 wt. %, 26 wt. %, 23 wt. %, 20 wt. %, 18 wt. %, 16 wt. %, 14 wt. %, or 12 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 1.1 wt. %, 2.1 wt. %, 3.1 wt. %, 4.1 wt. %, 5.1 wt. %, 6.1 wt. %, 7.1 wt. %, 8.1 wt. %, 9.1 wt. %, 10 wt. %, 11 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 15 wt. %, 16 wt. %, 17 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 26 wt. %, 29 wt. %, or 32 wt. %. In certain embodiments, the treatment component comprises about 20 wt. % or less of the oxidant.
In certain embodiments, the oxidant of the treatment component of the explosive formulation of the first aspect of the invention may have a standard oxidation potential of from about 0.8 V to about 3 V, or from about 1 V to about 3 V, about 1.2 V to about 3 V, about 1.3 V to about 3 V, about 1.4 V to about 3 V, about 1.5 V to about 3 V, about 1.6 V to about 3 V, about 1.7 V to about 3 V, about 1.8 V to about 3 V, about 1.9 V to about 3 V, about 2 V to about 3 V, about 1.1 V to about 2.9 V, about 1.1 V to about 2.8 V, about 1.1 V to about 2.7 V, about 1.1 V to about 2.6 V, about 1.1 V to about 2.5 V, about 1.1 V to about 2.4 V, about 1.1 V to about 2.3 V, about 1.1 V to about 2.2 V, about 1.1 V to about 2.1 V, about 1.1 V to about 2 V, about 1.4 V to about 2 V, about 1.5 V to about 2 V, about 1.6 V to about 2 V, about 1.8 V to about 2 V, about 1.9 V to about 2 V, about 1.4 V to about 1.9 V, about 1.4 V to about 1.8 V, about 1.4 V to about 1.6 V, or about 1.4 V to about 1.5 V. It may be greater than or equal to about 0.8, V, 0.9 V, 1 V, 1.1 V, 1.2 V, 1.3 V, 1.4 V, 1.5 V, or 1.6 V. It may be less than or equal to about 3 V, 2.9 V, 2.8 V, 2.7 V, 2.6 V, 2.5 V, 2.4 V, 2.3 V, 2.2 V, 2.1 V, 2 V, 1.9 V, or 1.8 V. In certain embodiments, it may be, for example, about 0.8 V, 0.9 V, 1 V, 1.1 V, 1.2 V, 1.3 V, 1.4 V, 1.5 V, 1.6 V, 1.7 V, 1.8 V, 1.9 V, 2 V, 2.1 V, 2.2 V, 2.3 V, 2.4 V, 2.5 V, 2.6 V, 2.7 V, 2.8 V, 2.9 V, or 3 V.
In certain embodiments, the treatment component of the explosive formulation of the first aspect of the invention further comprises an acid or a buffer. The acid or buffer may comprise an organic acid and/or a salt thereof. The acid or buffer may comprise a polyprotic organic acid and/or a salt thereof. The acid or buffer may comprise, for example, one or more of citric acid, EDTA, phosphoric acid, lactic acid, acetic acid, and salts thereof.
In certain embodiments, the pH of the treatment component of the explosive formulation of the first aspect of the invention may be from about 2 to about 8, or from about 2.1 to about 8, about 2.2 to about 8, about 2.3 to about 8, about 2.4 to about 8, about 2.5 to about 8, about 2.7 to about 8, about 2.9 to about 8, about 3.1 to about 8, about 3.3 to about 8, about 3.5 to about 8, about 3.7 to about 8, about 3.9 to about 8, about 4.1 to about 8, about 4.3 to about 8, about 4.5 to about 8, about 2 to about 7.6, about 2 to about 7.3, about 2 to about 7, about 2 to about 6.6, about 2 to about 6.2, about 2 to about 5.9, about 2 to about 5.6, about 2 to about 5.2, about 2 to about 4.8, about 2 to about 4.5, about 2.5 to about 4.5, about 2.9 to about 4.5, about 3.3 to about 4.5, about 3.7 to about 4.5, about 4.1 to about 4.5, about 2.5 to about 4.1, about 2.5 to about 3.7, about 2.5 to about 3.3, or about 2.5 to about 2.9. It may be greater than or equal to about 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.7, 2.9, 3, 3.1, 3.2, or 3.3. It may be less than or equal to about 8, 7.6, 7.3, 7, 6.6, 6.2, 5.9, 5.6, 5.2, 4.8, 4.5, 4.3, 4.1, 3.9, or 3.7. In certain embodiments, it may be, for example, about 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 5.2, 5.6, 5.9, 6.2, 6.6, 7, 7.3, 7.6, or 8. In certain embodiments, the pH of the treatment component is from about 2.5 to about 7, about 2.5 to about 6, about 2.5 to about 4.5, or about 3 to about 4.
In certain embodiments, the treatment component of the explosive formulation of the first aspect of the invention comprises a sulphide dissolution enhancer. The sulphide dissolution enhancer may act to improve the solubility of any sulphides at the inner surface of a blast hole to thereby enable the oxidant to more efficiently oxidise sulphides contained therein. It may, for example, act to chelate a component of the sulphides. For example, in the case where the sulphide is a metal sulphide, the sulphide dissolution enhancer may form a complex with the metal ion and/or the sulphide ion of the metal sulphide. The sulphide dissolution enhancer may, for example, be selected from the group consisting of: citric acid, nitrous acid, sodium hydrogen sulphate, sodium tetraborate decahydrate, ferric ion salts, EDTA, and emulsifiers. In certain embodiments, the sulphide dissolution enhancer may be the same as the acid or buffer disclosed hereinbefore. The sulphide dissolution enhancer may be present in the treatment component at a concentration of from about 0.01 wt. % to about 50 wt. %, or from about 0.028 wt. % to about 50 wt. %, about 0.046 wt. % to about 50 wt. %, about 0.064 wt. % to about 50 wt. %, about 0.082 wt. % to about 50 wt. %, about 0.1 wt. % to about 50 wt. %, about 2.1 wt. % to about 50 wt. %, about 4.1 wt. % to about 50 wt. %, about 6.1 wt. % to about 50 wt. %, about 8.1 wt. % to about 50 wt. %, about 10 wt. % to about 50 wt. %, about 12 wt. % to about 50 wt. %, about 14 wt. % to about 50 wt. %, about 16 wt. % to about 50 wt. %, about 18 wt. % to about 50 wt. %, about 20 wt. % to about 50 wt. %, about 0.01 wt. % to about 47 wt. %, about 0.01 wt. % to about 44 wt. %, about 0.01 wt. % to about 41 wt. %, about 0.01 wt. % to about 38 wt. %, about 0.01 wt. % to about 35 wt. %, about 0.01 wt. % to about 32 wt. %, about 0.01 wt. % to about 29 wt. %, about 0.01 wt. % to about 26 wt. %, about 0.01 wt. % to about 23 wt. %, about 0.01 wt. % to about 20 wt. %, about 0.1 wt. % to about 20 wt. %, about 4.1 wt. % to about 20 wt. %, about 8.1 wt. % to about 20 wt. %, about 12 wt. % to about 20 wt. %, about 16 wt. % to about 20 wt. %, about 0.1 wt. % to about 16 wt. %, about 0.1 wt. % to about 12 wt. %, about 0.1 wt. % to about 8.1 wt. %, or about 0.1 wt. % to about 4.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 2.1 wt. %, 4.1 wt. %, 6.1 wt. %, or 8.1 wt. %. It may be less than or equal to about 50 wt. %, 47 wt. %, 44 wt. %, 41 wt. %, 38 wt. %, 35 wt. %, 32 wt. %, 29 wt. %, 26 wt. %, 23 wt. %, 20 wt. %, 18 wt. %, 16 wt. %, 14 wt. %, or 12 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 1.1 wt. %, 2.1 wt. %, 3.1 wt. %, 4.1 wt. %, 5.1 wt. %, 6.1 wt. %, 7.1 wt. %, 8.1 wt. %, 9.1 wt. %, 10 wt. %, 11 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 15 wt. %, 16 wt. %, 17 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 26 wt. %, 29 wt. %, 32 wt. %, 35 wt. %, 38 wt. %, 41 wt. %, 44 wt. %, 47 wt. %, or 50 wt. %.
In certain embodiments, the treatment component of the explosive formulation of the first aspect of the invention may be in the form of a solid, optionally a solid powder, or a liquid. In the case where the treatment component is a liquid, it may be an aqueous solution or suspension. It may comprise water in an amount of from about 10 wt. % to about 97 wt. %, or from about 13 wt. % to about 97 wt. %, about 16 wt. % to about 97 wt. %, about 19 wt. % to about 97 wt. %, about 22 wt. % to about 97 wt. %, about 25 wt. % to about 97 wt. %, about 30 wt. % to about 97 wt. %, about 35 wt. % to about 97 wt. %, about 40 wt. % to about 97 wt. %, about 45 wt. % to about 97 wt. %, about 50 wt. % to about 97 wt. %, about 55 wt. % to about 97 wt. %, about 60 wt. % to about 97 wt. %, about 65 wt. % to about 97 wt. %, about 70 wt. % to about 97 wt. %, about 75 wt. % to about 97 wt. %, about 10 wt. % to about 95 wt. %, about 10 wt. % to about 93 wt. %, about 10 wt. % to about 90 wt. %, about 10 wt. % to about 88 wt. %, about 10 wt. % to about 86 wt. %, about 10 wt. % to about 84 wt. %, about 10 wt. % to about 82 wt. %, about 10 wt. % to about 79 wt. %, about 10 wt. % to about 77 wt. %, about 10 wt. % to about 75 wt. %, about 25 wt. % to about 75 wt. %, about 35 wt. % to about 75 wt. %, about 45 wt. % to about 75 wt. %, about 55 wt. % to about 75 wt. %, about 65 wt. % to about 75 wt. %, about 25 wt. % to about 65 wt. %, about 25 wt. % to about 55 wt. %, about 25 wt. % to about 45 wt. %, or about 25 wt. % to about 35 wt. %. It may be greater than or equal to about 10 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 16 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 22 wt. %, 24 wt. %, 25 wt. %, 30 wt. %, 35 wt. %, 40 wt. %, or 45 wt. %. It may be less than or equal to about 97 wt. %, 95 wt. %, 93 wt. %, 90 wt. %, 88 wt. %, 86 wt. %, 84 wt. %, 82 wt. %, 79 wt. %, 77 wt. %, 75 wt. %, 70 wt. %, 65 wt. %, 60 wt. %, or 55 wt. %. In certain embodiments, it may be, for example, about 10 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 16 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 22 wt. %, 24 wt. %, 25 wt. %, 28 wt. %, 30 wt. %, 32 wt. %, 35 wt. %, 38 wt. %, 40 wt. %, 42 wt. %, 45 wt. %, 48 wt. %, 50 wt. %, 52 wt. %, 55 wt. %, 58 wt. %, 60 wt. %, 62 wt. %, 65 wt. %, 68 wt. %, 70 wt. %, 72 wt. %, 75 wt. %, 79 wt. %, 82 wt. %, 84 wt. %, 86 wt. %, 88 wt. %, 90 wt. %, 93 wt. %, 95 wt. %, or 97 wt. %.
In certain embodiments, the blasting component of the explosive formulation of the first aspect of the invention comprises one or more inhibitors which are capable of preventing or minimizing the risk of premature detonation of the explosive. The one or more inhibitors may be present in the blasting component at a total concentration of from about 0.01 wt. % to about 10 wt. %, or from about 0.028 wt. % to about 10 wt. %, about 0.046 wt. % to about 10 wt. %, about 0.064 wt. % to about 10 wt. %, about 0.082 wt. % to about 10 wt. %, about 0.1 wt. % to about 10 wt. %, about 0.59 wt. % to about 10 wt. %, about 1.1 wt. % to about 10 wt. %, about 1.6 wt. % to about 10 wt. %, about 2.1 wt. % to about 10 wt. %, about 2.6 wt. % to about 10 wt. %, about 3 wt. % to about 10 wt. %, about 3.5 wt. % to about 10 wt. %, about 4 wt. % to about 10 wt. %, about 4.5 wt. % to about 10 wt. %, about 5 wt. % to about 10 wt. %, about 0.01 wt. % to about 9.5 wt. %, about 0.01 wt. % to about 9 wt. %, about 0.01 wt. % to about 8.5 wt. %, about 0.01 wt. % to about 8 wt. %, about 0.01 wt. % to about 7.5 wt. %, about 0.01 wt. % to about 7 wt. %, about 0.01 wt. % to about 6.5 wt. %, about 0.01 wt. % to about 6 wt. %, about 0.01 wt. % to about 5.5 wt. %, about 0.01 wt. % to about 5 wt. %, about 0.1 wt. % to about 5 wt. %, about 1.1 wt. % to about 5 wt. %, about 2.1 wt. % to about 5 wt. %, about 3 wt. % to about 5 wt. %, about 4 wt. % to about 5 wt. %, about 0.1 wt. % to about 4 wt. %, about 0.1 wt. % to about 3 wt. %, about 0.1 wt. % to about 2.1 wt. %, or about 0.1 wt. % to about 1.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.59 wt. %, 1.1 wt. %, 1.6 wt. %, or 2.1 wt. %. It may be less than or equal to about 10 wt. %, 9.5 wt. %, 9 wt. %, 8.5 wt. %, 8 wt. %, 7.5 wt. %, 7 wt. %, 6.5 wt. %, 6 wt. %, 5.5 wt. %, 5 wt. %, 4.5 wt. %, 4 wt. %, 3.5 wt. %, or 3 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.34 wt. %, 0.59 wt. %, 0.84 wt. %, 1.1 wt. %, 1.3 wt. %, 1.6 wt. %, 1.8 wt. %, 2.1 wt. %, 2.3 wt. %, 2.6 wt. %, 2.8 wt. %, 3 wt. %, 3.3 wt. %, 3.5 wt. %, 3.8 wt. %, 4 wt. %, 4.3 wt. %, 4.5 wt. %, 4.8 wt. %, 5 wt. %, 6 wt. %, 6.5 wt. %, 7 wt. %, 7.5 wt. %, 8 wt. %, 8.5 wt. %, 9 wt. %, 9.5 wt. %, or 10 wt. %. Alternatively, in other embodiments, the blasting component may not comprise any inhibitors.
In certain embodiments, the treatment component of the explosive formulation of the first aspect of the invention comprises a reaction status reporter. The reaction status reporter is capable of indicating the progress of the oxidation of the oxidizable material in a blast hole by the oxidant of the treatment component. The reaction status reporter may be, for example, a pH indicator or a redox indicator. The reaction status reporter may be present in the treatment component at a concentration of from about 0.01 wt. % to about 10 wt. %, or from about 0.028 wt. % to about 10 wt. %, about 0.046 wt. % to about 10 wt. %, about 0.064 wt. % to about 10 wt. %, about 0.082 wt. % to about 10 wt. %, about 0.1 wt. % to about 10 wt. %, about 0.59 wt. % to about 10 wt. %, about 1.1 wt. % to about 10 wt. %, about 1.6 wt. % to about 10 wt. %, about 2.1 wt. % to about 10 wt. %, about 2.6 wt. % to about 10 wt. %, about 3 wt. % to about 10 wt. %, about 3.5 wt. % to about 10 wt. %, about 4 wt. % to about 10 wt. %, about 4.5 wt. % to about 10 wt. %, about 5 wt. % to about 10 wt. %, about 0.01 wt. % to about 9.5 wt. %, about 0.01 wt. % to about 9 wt. %, about 0.01 wt. % to about 8.5 wt. %, about 0.01 wt. % to about 8 wt. %, about 0.01 wt. % to about 7.5 wt. %, about 0.01 wt. % to about 7 wt. %, about 0.01 wt. % to about 6.5 wt. %, about 0.01 wt. % to about 6 wt. %, about 0.01 wt. % to about 5.5 wt. %, about 0.01 wt. % to about 5 wt. %, about 0.1 wt. % to about 5 wt. %, about 1.1 wt. % to about 5 wt. %, about 2.1 wt. % to about 5 wt. %, about 3 wt. % to about 5 wt. %, about 4 wt. % to about 5 wt. %, about 0.1 wt. % to about 4 wt. %, about 0.1 wt. % to about 3 wt. %, about 0.1 wt. % to about 2.1 wt. %, or about 0.1 wt. % to about 1.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.59 wt. %, 1.1 wt. %, 1.6 wt. %, or 2.1 wt. %. It may be less than or equal to about 10 wt. %, 9.5 wt. %, 9 wt. %, 8.5 wt. %, 8 wt. %, 7.5 wt. %, 7 wt. %, 6.5 wt. %, 6 wt. %, 5.5 wt. %, 5 wt. %, 4.5 wt. %, 4 wt. %, 3.5 wt. %, or 3 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.34 wt. %, 0.59 wt. %, 0.84 wt. %, 1.1 wt. %, 1.3 wt. %, 1.6 wt. %, 1.8 wt. %, 2.1 wt. %, 2.3 wt. %, 2.6 wt. %, 2.8 wt. %, 3 wt. %, 3.3 wt. %, 3.5 wt. %, 3.8 wt. %, 4 wt. %, 4.3 wt. %, 4.5 wt. %, 4.8 wt. %, 5 wt. %, 6 wt. %, 6.5 wt. %, 7 wt. %, 7.5 wt. %, 8 wt. %, 8.5 wt. %, 9 wt. %, 9.5 wt. %, or 10 wt. %.
In a second aspect of the invention there is provided a method for loading a blast hole in reactive ground with an explosive formulation of the first aspect of the invention described herein, the method comprising the steps of:
The following options may be used as part of, in conjunction with, the method of the second aspect of the invention, either individually or in any combination.
In certain embodiments, the application of loading of the treatment component to the blast hole induces oxidisation of the oxidisable material of the blast hole.
In certain embodiments, the oxidant of the treatment component of the explosive formulation used in the method of the second aspect of the invention is selected from the group consisting of nitrates, hypochlorites, percarbonates, perchlorates, and peroxides. It may, for example, comprise ammonium nitrate, calcium nitrate, potassium nitrate, sodium perchlorate, sodium nitrate, sodium hypochlorite, sodium percarbonate, and/or hydrogen peroxide. In certain embodiments, the oxidant comprises sodium nitrate.
In certain embodiments, the oxidant of the treatment component of the explosive formulation used in the method of the second aspect of the invention may have a standard oxidation potential of from about 0.8 V to about 3 V, or from about 1 V to about 3 V, about 1.2 V to about 3 V, about 1.3 V to about 3 V, about 1.4 V to about 3 V, about 1.5 V to about 3 V, about 1.6 V to about 3 V, about 1.7 V to about 3 V, about 1.8 V to about 3 V, about 1.9 V to about 3 V, about 2 V to about 3 V, about 1.1 V to about 2.9 V, about 1.1 V to about 2.8 V, about 1.1 V to about 2.7 V, about 1.1 V to about 2.6 V, about 1.1 V to about 2.5 V, about 1.1 V to about 2.4 V, about 1.1 V to about 2.3 V, about 1.1 V to about 2.2 V, about 1.1 V to about 2.1 V, about 1.1 V to about 2 V, about 1.4 V to about 2 V, about 1.5 V to about 2 V, about 1.6 V to about 2 V, about 1.8 V to about 2 V, about 1.9 V to about 2 V, about 1.4 V to about 1.9 V, about 1.4 V to about 1.8 V, about 1.4 V to about 1.6 V, or about 1.4 V to about 1.5 V. It may be greater than or equal to about 0.8, V, 0.9 V, 1 V, 1.1 V, 1.2 V, 1.3 V, 1.4 V, 1.5 V, or 1.6 V. It may be less than or equal to about 3 V, 2.9 V, 2.8 V, 2.7 V, 2.6 V, 2.5 V, 2.4 V, 2.3 V, 2.2 V, 2.1 V, 2 V, 1.9 V, or 1.8 V. In certain embodiments, it may be, for example, about 0.8 V, 0.9 V, 1 V, 1.1 V, 1.2 V, 1.3 V, 1.4 V, 1.5 V, 1.6 V, 1.7 V, 1.8 V, 1.9 V, 2 V, 2.1 V, 2.2 V, 2.3 V, 2.4 V, 2.5 V, 2.6 V, 2.7 V, 2.8 V, 2.9 V, or 3 V.
In certain embodiments, the oxidant of the treatment component of the explosive formulation used in the method of the second aspect of the invention may be present in the treatment component in a concentration of from about 0.01 wt. % to about 50 wt. %, or from about 0.028 wt. % to about 50 wt. %, about 0.046 wt. % to about 50 wt. %, about 0.064 wt. % to about 50 wt. %, about 0.082 wt. % to about 50 wt. %, about 0.1 wt. % to about 50 wt. %, about 2.1 wt. % to about 50 wt. %, about 4.1 wt. % to about 50 wt. %, about 6.1 wt. % to about 50 wt. %, about 8.1 wt. % to about 50 wt. %, about 10 wt. % to about 50 wt. %, about 12 wt. % to about 50 wt. %, about 14 wt. % to about 50 wt. %, about 16 wt. % to about 50 wt. %, about 18 wt. % to about 50 wt. %, about 20 wt. % to about 50 wt. %, about 0.01 wt. % to about 47 wt. %, about 0.01 wt. % to about 44 wt. %, about 0.01 wt. % to about 41 wt. %, about 0.01 wt. % to about 38 wt. %, about 0.01 wt. % to about 35 wt. %, about 0.01 wt. % to about 32 wt. %, about 0.01 wt. % to about 29 wt. %, about 0.01 wt. % to about 26 wt. %, about 0.01 wt. % to about 23 wt. %, about 0.01 wt. % to about 20 wt. %, about 0.1 wt. % to about 20 wt. %, about 4.1 wt. % to about 20 wt. %, about 8.1 wt. % to about 20 wt. %, about 12 wt. % to about 20 wt. %, about 16 wt. % to about 20 wt. %, about 0.1 wt. % to about 16 wt. %, about 0.1 wt. % to about 12 wt. %, about 0.1 wt. % to about 8.1 wt. %, or about 0.1 wt. % to about 4.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 2.1 wt. %, 4.1 wt. %, 6.1 wt. %, or 8.1 wt. %. It may be less than or equal to about 50 wt. %, 47 wt. %, 44 wt. %, 41 wt. %, 38 wt. %, 35 wt. %, 32 wt. %, 29 wt. %, 26 wt. %, 23 wt. %, 20 wt. %, 18 wt. %, 16 wt. %, 14 wt. %, or 12 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 1.1 wt. %, 2.1 wt. %, 3.1 wt. %, 4.1 wt. %, 5.1 wt. %, 6.1 wt. %, 7.1 wt. %, 8.1 wt. %, 9.1 wt. %, 10 wt. %, 11 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 15 wt. %, 16 wt. %, 17 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 26 wt. %, 29 wt. %, 32 wt. %, 35 wt. %, 38 wt. %, 41 wt. %, 44 wt. %, 47 wt. %, or 50 wt. %. In certain embodiments, the treatment component comprises about 20 wt. % or less of the oxidant.
In certain embodiments, the treatment component of the explosive formulation used in the method of the second aspect of the invention further comprises an acid or a buffer. The acid or buffer may comprise an organic acid and/or a salt thereof. The acid or buffer may comprise a polyprotic organic acid and/or a salt thereof. The acid or buffer may comprise, for example, one or more of citric acid, EDTA, phosphoric acid, lactic acid, acetic acid, and salts thereof.
In certain embodiments, the pH of the treatment component of the explosive formulation used in the method of the second aspect of the invention may be from about 2 to about 8, or from about 2.1 to about 8, about 2.2 to about 8, about 2.3 to about 8, about 2.4 to about 8, about 2.5 to about 8, about 2.7 to about 8, about 2.9 to about 8, about 3.1 to about 8, about 3.3 to about 8, about 3.5 to about 8, about 3.7 to about 8, about 3.9 to about 8, about 4.1 to about 8, about 4.3 to about 8, about 4.5 to about 8, about 2 to about 7.6, about 2 to about 7.3, about 2 to about 7, about 2 to about 6.6, about 2 to about 6.2, about 2 to about 5.9, about 2 to about 5.6, about 2 to about 5.2, about 2 to about 4.8, about 2 to about 4.5, about 2.5 to about 4.5, about 2.9 to about 4.5, about 3.3 to about 4.5, about 3.7 to about 4.5, about 4.1 to about 4.5, about 2.5 to about 4.1, about 2.5 to about 3.7, about 2.5 to about 3.3, or about 2.5 to about 2.9. It may be greater than or equal to about 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.7, 2.9, 3, 3.1, 3.2, or 3.3. It may be less than or equal to about 8, 7.6, 7.3, 7, 6.6, 6.2, 5.9, 5.6, 5.2, 4.8, 4.5, 4.3, 4.1, 3.9, or 3.7. In certain embodiments, it may be, for example, about 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 5.2, 5.6, 5.9, 6.2, 6.6, 7, 7.3, 7.6, or 8. In certain embodiments, the pH of the treatment component is from about 2.5 to about 7, about 2.5 to about 6, about 2.5 to about 4.5, or about 3 to about 4.
In certain embodiments of the method of the second aspect of the invention, the oxidisable material comprised or contained in the blast hole in the reactive ground comprises one or more sulphides or disulphides. In certain embodiments, oxidisable material comprises iron sulphide, iron disulphide, iron copper sulphide, copper (II) sulphide, lead sulphide, molybdenum disulphide, zinc sulphide, and/or copper (I) sulphide.
In certain embodiments, the explosive of the blasting component of the explosive formulation used in the method of the second aspect of the invention comprises a reducible material. In certain embodiments, the explosive comprises a nitrate. In certain specific embodiments, the explosive comprises ammonium nitrate, calcium nitrate, potassium nitrate, sodium perchlorate, or sodium nitrate.
In certain embodiments of the second aspect of the invention, the reactive ground in which the blast hole is located is hot reactive ground. The temperature of the hot reactive ground may be from about 55° C. to about 220° C., or from about 58° C. to about 220° C., about 61° C. to about 220° C., about 64° C. to about 220° C., about 67° C. to about 220° C., about 70° C. to about 220° C., about 74° C. to about 220° C., about 78° C. to about 220° C., about 82° C. to about 220° C., about 86° C. to about 220° C., about 90° C. to about 220° C., about 94° C. to about 220° C., about 98° C. to about 220° C., about 100° C. to about 220° C., about 110° C. to about 220° C., about 55° C. to about 210° C., about 55° C. to about 200° C., about 55° C. to about 190° C., about 55° C. to about 180° C., about 55° C. to about 160° C., about 55° C. to about 150° C., about 55° C. to about 140° C., about 55° C. to about 130° C., about 55° C. to about 120° C., about 55° C. to about 110° C., about 70° C. to about 110° C., about 78° C. to about 110° C., about 86° C. to about 110° C., about 94° C. to about 110° C., about 100° C. to about 110° C., about 70° C. to about 100° C., about 70° C. to about 94° C., about 70° C. to about 86° C., or about 70° C. to about 78° C. It may be greater than or equal to about 55° C., 56° C., 58° C., 60° C., 61° C., 62° C., 64° C., 66° C., 67° C., 68° C., 70° C., 74° C., 78° C., 82° C., or 86° C. It may be less than or equal to about 220° C., 210° C., 200° C., 190° C., 180° C., 160° C., 150° C., 140° C., 130° C., 120° C., 110° C., 100° C., 98° C., or 94° C. In certain embodiments, it may be, for example, about 55° C., 56° C., 58° C., 60° C., 61° C., 62° C., 64° C., 66° C., 67° C., 68° C., 70° C., 72° C., 74° C., 76° C., 78° C., 80° C., 82° C., 84° C., 86° C., 88° C., 90° C., 92° C., 94° C., 96° C., 98° C., 100° C., 102° C., 105° C., 110° C., 115° C., 120° C., 130° C., 140° C., 150° C., 160° C., 180° C., 190° C., 200° C., 210° C., or 220° C.
In certain embodiments of the method of the second aspect of the invention, the blast hole may be any size or shape that is suitable for loading the treatment component and the blasting component. In certain embodiments, the blast hole may be a cylindrical shape. The blast hole may have a diameter of from about 10 mm to about 500 mm, or from about 24 mm to about 500 mm, about 38 mm to about 500 mm, about 52 mm to about 500 mm, about 66 mm to about 500 mm, about 80 mm to about 500 mm, about 87 mm to about 500 mm, about 94 mm to about 500 mm, about 101 mm to about 500 mm, about 108 mm to about 500 mm, about 115 mm to about 500 mm, about 122 mm to about 500 mm, about 129 mm to about 500 mm, about 136 mm to about 500 mm, about 143 mm to about 500 mm, about 150 mm to about 500 mm, about 10 mm to about 465 mm, about 10 mm to about 430 mm, about 10 mm to about 395 mm, about 10 mm to about 360 mm, about 10 mm to about 325 mm, about 10 mm to about 290 mm, about 10 mm to about 255 mm, about 10 mm to about 220 mm, about 10 mm to about 185 mm, about 10 mm to about 150 mm, about 80 mm to about 150 mm, about 94 mm to about 150 mm, about 108 mm to about 150 mm, about 122 mm to about 150 mm, about 136 mm to about 150 mm, about 80 mm to about 136 mm, about 80 mm to about 122 mm, about 80 mm to about 108 mm, or about 80 mm to about 94 mm. It may be greater than or equal to about 10 mm, 17 mm, 24 mm, 31 mm, 38 mm, 45 mm, 52 mm, 59 mm, 66 mm, 73 mm, 80 mm, 87 mm, 94 mm, 101 mm, or 108 mm. It may be less than or equal to about 500 mm, 465 mm, 430 mm, 395 mm, 360 mm, 325 mm, 290 mm, 255 mm, 220 mm, 185 mm, 150 mm, 143 mm, 136 mm, 129 mm, or 122 mm. In certain embodiments, it may be, for example, about 10 mm, 17 mm, 24 mm, 31 mm, 38 mm, 45 mm, 52 mm, 59 mm, 66 mm, 73 mm, 80 mm, 83.5 mm, 87 mm, 90.5 mm, 94 mm, 97.5 mm, 101 mm, 104 mm, 108 mm, 112 mm, 115 mm, 118 mm, 122 mm, 126 mm, 129 mm, 132 mm, 136 mm, 140 mm, 143 mm, 146 mm, 150 mm, 220 mm, 255 mm, 290 mm, 325 mm, 360 mm, 395 mm, 430 mm, 465 mm, or 500 mm.
In certain embodiments of the method of the second aspect of the invention, the blast hole may have a depth of from about 100 mm to about 50 m, or from about 480 mm to about 50 m, about 860 mm to about 50 m, about 1.24 m to about 50 m, about 1.62 m to about 50 m, about 2 m to about 50 m, about 2.8 m to about 50 m, about 3.6 m to about 50 m, about 4.4 m to about 50 m, about 5.2 m to about 50 m, about 6 m to about 50 m, about 6.8 m to about 50 m, about 7.6 m to about 50 m, about 8.4 m to about 50 m, about 9.2 m to about 50 m, about 10 m to about 50 m, about 100 mm to about 46 m, about 100 mm to about 42 m, about 100 mm to about 38 m, about 100 mm to about 34 m, about 100 mm to about 30 m, about 100 mm to about 26 m, about 100 mm to about 22 m, about 100 mm to about 18 m, about 100 mm to about 14 m, about 100 mm to about 10 m, about 2 m to about 10 m, about 3.6 m to about 10 m, about 5.2 m to about 10 m, about 6.8 m to about 10 m, about 8.4 m to about 10 m, about 2 m to about 8.4 m, about 2 m to about 6.8 m, about 2 m to about 5.2 m, or about 2 m to about 3.6 m. It may be greater than or equal to about 100 mm, 290 mm, 480 mm, 670 mm, 860 mm, 1.05 m, 1.24 m, 1.43 m, 1.62 m, 1.81 m, 2 m, 2.8 m, 3.6 m, 4.4 m, or 5.2 m. It may be less than or equal to about 50 m, 46 m, 42 m, 38 m, 34 m, 30 m, 26 m, 22 m, 18 m, 14 m, 10 m, 9.2 m, 8.4 m, 7.6 m, or 6.8 m. In certain embodiments, it may be, for example, about 100 mm, 290 mm, 480 mm, 670 mm, 860 mm, 1.05 m, 1.24 m, 1.43 m, 1.62 m, 1.81 m, 2 m, 2.4 m, 2.8 m, 3.2 m, 3.6 m, 4 m, 4.4 m, 4.8 m, 5.2 m, 5.6 m, 6 m, 6.4 m, 6.8 m, 7.2 m, 7.6 m, 8 m, 8.4 m, 8.8 m, 9.2 m, 9.6 m, 10 m, 18 m, 22 m, 26 m, 30 m, 34 m, 38 m, 42 m, 46 m, or 50 m.
In certain embodiments, the treatment component of the explosive formulation used in the method of the second aspect of the invention comprises a sulphide dissolution enhancer. The sulphide dissolution enhancer may act to improve the solubility of any sulphides at the inner surface of the blast hole to thereby enable the oxidant to more efficiently oxidise the sulphide. It may, for example, act to chelate a component of the sulphides. For example, in the case where the sulphide is a metal sulphide, the sulphide dissolution enhancer may form a complex with the metal ion and/or the sulphide ion of the metal sulphide. The sulphide dissolution enhancer may, for example, be selected from the group consisting of: citric acid, nitrous acid, sodium hydrogen sulphate, sodium tetraborate decahydrate, ferric ion salts, EDTA, and emulsifiers. In certain embodiments, the sulphide dissolution enhancer may be the same as the acid or buffer disclosed hereinbefore. The sulphide dissolution enhancer may be present in the treatment component at a concentration of from about 0.01 wt. % to about 50 wt. %, or from about 0.028 wt. % to about 50 wt. %, about 0.046 wt. % to about 50 wt. %, about 0.064 wt. % to about 50 wt. %, about 0.082 wt. % to about 50 wt. %, about 0.1 wt. % to about 50 wt. %, about 2.1 wt. % to about 50 wt. %, about 4.1 wt. % to about 50 wt. %, about 6.1 wt. % to about 50 wt. %, about 8.1 wt. % to about 50 wt. %, about 10 wt. % to about 50 wt. %, about 12 wt. % to about 50 wt. %, about 14 wt. % to about 50 wt. %, about 16 wt. % to about 50 wt. %, about 18 wt. % to about 50 wt. %, about 20 wt. % to about 50 wt. %, about 0.01 wt. % to about 47 wt. %, about 0.01 wt. % to about 44 wt. %, about 0.01 wt. % to about 41 wt. %, about 0.01 wt. % to about 38 wt. %, about 0.01 wt. % to about 35 wt. %, about 0.01 wt. % to about 32 wt. %, about 0.01 wt. % to about 29 wt. %, about 0.01 wt. % to about 26 wt. %, about 0.01 wt. % to about 23 wt. %, about 0.01 wt. % to about 20 wt. %, about 0.1 wt. % to about 20 wt. %, about 4.1 wt. % to about 20 wt. %, about 8.1 wt. % to about 20 wt. %, about 12 wt. % to about 20 wt. %, about 16 wt. % to about 20 wt. %, about 0.1 wt. % to about 16 wt. %, about 0.1 wt. % to about 12 wt. %, about 0.1 wt. % to about 8.1 wt. %, or about 0.1 wt. % to about 4.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 2.1 wt. %, 4.1 wt. %, 6.1 wt. %, or 8.1 wt. %. It may be less than or equal to about 50 wt. %, 47 wt. %, 44 wt. %, 41 wt. %, 38 wt. %, 35 wt. %, 32 wt. %, 29 wt. %, 26 wt. %, 23 wt. %, 20 wt. %, 18 wt. %, 16 wt. %, 14 wt. %, or 12 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 1.1 wt. %, 2.1 wt. %, 3.1 wt. %, 4.1 wt. %, 5.1 wt. %, 6.1 wt. %, 7.1 wt. %, 8.1 wt. %, 9.1 wt. %, 10 wt. %, 11 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 15 wt. %, 16 wt. %, 17 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 26 wt. %, 29 wt. %, 32 wt. %, 35 wt. %, 38 wt. %, 41 wt. %, 44 wt. %, 47 wt. %, or 50 wt. %.
In certain embodiments, the treatment component of the explosive formulation used in the method of the second aspect of the invention may be in the form of a solid, optionally a solid powder, or a liquid. In the case where the treatment component is a liquid, it may be an aqueous solution or suspension. It may comprise water in an amount of from about 10 wt. % to about 97 wt. %, or from about 13 wt. % to about 97 wt. %, about 16 wt. % to about 97 wt. %, about 19 wt. % to about 97 wt. %, about 22 wt. % to about 97 wt. %, about 25 wt. % to about 97 wt. %, about 30 wt. % to about 97 wt. %, about 35 wt. % to about 97 wt. %, about 40 wt. % to about 97 wt. %, about 45 wt. % to about 97 wt. %, about 50 wt. % to about 97 wt. %, about 55 wt. % to about 97 wt. %, about 60 wt. % to about 97 wt. %, about 65 wt. % to about 97 wt. %, about 70 wt. % to about 97 wt. %, about 75 wt. % to about 97 wt. %, about 10 wt. % to about 95 wt. %, about 10 wt. % to about 93 wt. %, about 10 wt. % to about 90 wt. %, about 10 wt. % to about 88 wt. %, about 10 wt. % to about 86 wt. %, about 10 wt. % to about 84 wt. %, about 10 wt. % to about 82 wt. %, about 10 wt. % to about 79 wt. %, about 10 wt. % to about 77 wt. %, about 10 wt. % to about 75 wt. %, about 25 wt. % to about 75 wt. %, about 35 wt. % to about 75 wt. %, about 45 wt. % to about 75 wt. %, about 55 wt. % to about 75 wt. %, about 65 wt. % to about 75 wt. %, about 25 wt. % to about 65 wt. %, about 25 wt. % to about 55 wt. %, about 25 wt. % to about 45 wt. %, or about 25 wt. % to about 35 wt. %. It may be greater than or equal to about 10 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 16 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 22 wt. %, 24 wt. %, 25 wt. %, 30 wt. %, 35 wt. %, 40 wt. %, or 45 wt. %. It may be less than or equal to about 97 wt. %, 95 wt. %, 93 wt. %, 90 wt. %, 88 wt. %, 86 wt. %, 84 wt. %, 82 wt. %, 79 wt. %, 77 wt. %, 75 wt. %, 70 wt. %, 65 wt. %, 60 wt. %, or 55 wt. %. In certain embodiments, it may be, for example, about 10 wt. %, 12 wt. %, 13 wt. %, 14 wt. %, 16 wt. %, 18 wt. %, 19 wt. %, 20 wt. %, 22 wt. %, 24 wt. %, 25 wt. %, 28 wt. %, 30 wt. %, 32 wt. %, 35 wt. %, 38 wt. %, 40 wt. %, 42 wt. %, 45 wt. %, 48 wt. %, 50 wt. %, 52 wt. %, 55 wt. %, 58 wt. %, 60 wt. %, 62 wt. %, 65 wt. %, 68 wt. %, 70 wt. %, 72 wt. %, 75 wt. %, 79 wt. %, 82 wt. %, 84 wt. %, 86 wt. %, 88 wt. %, 90 wt. %, 93 wt. %, 95 wt. %, or 97 wt. %.
In certain embodiments, the blasting component of the explosive formulation used in the method of the second aspect of the invention comprises an explosive mixture. In certain embodiments, the explosive mixture comprises one or more inhibitors which are capable of preventing or minimizing the risk of premature detonation of the explosive. The one or more inhibitors may be present in the explosive mixture at a total concentration of from about 0.01 wt. % to about 10 wt. %, or from about 0.028 wt. % to about 10 wt. %, about 0.046 wt. % to about 10 wt. %, about 0.064 wt. % to about 10 wt. %, about 0.082 wt. % to about 10 wt. %, about 0.1 wt. % to about 10 wt. %, about 0.59 wt. % to about 10 wt. %, about 1.1 wt. % to about 10 wt. %, about 1.6 wt. % to about 10 wt. %, about 2.1 wt. % to about 10 wt. %, about 2.6 wt. % to about 10 wt. %, about 3 wt. % to about 10 wt. %, about 3.5 wt. % to about 10 wt. %, about 4 wt. % to about 10 wt. %, about 4.5 wt. % to about 10 wt. %, about 5 wt. % to about 10 wt. %, about 0.01 wt. % to about 9.5 wt. %, about 0.01 wt. % to about 9 wt. %, about 0.01 wt. % to about 8.5 wt. %, about 0.01 wt. % to about 8 wt. %, about 0.01 wt. % to about 7.5 wt. %, about 0.01 wt. % to about 7 wt. %, about 0.01 wt. % to about 6.5 wt. %, about 0.01 wt. % to about 6 wt. %, about 0.01 wt. % to about 5.5 wt. %, about 0.01 wt. % to about 5 wt. %, about 0.1 wt. % to about 5 wt. %, about 1.1 wt. % to about 5 wt. %, about 2.1 wt. % to about 5 wt. %, about 3 wt. % to about 5 wt. %, about 4 wt. % to about 5 wt. %, about 0.1 wt. % to about 4 wt. %, about 0.1 wt. % to about 3 wt. %, about 0.1 wt. % to about 2.1 wt. %, or about 0.1 wt. % to about 1.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.59 wt. %, 1.1 wt. %, 1.6 wt. %, or 2.1 wt. %. It may be less than or equal to about 10 wt. %, 9.5 wt. %, 9 wt. %, 8.5 wt. %, 8 wt. %, 7.5 wt. %, 7 wt. %, 6.5 wt. %, 6 wt. %, 5.5 wt. %, 5 wt. %, 4.5 wt. %, 4 wt. %, 3.5 wt. %, or 3 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.34 wt. %, 0.59 wt. %, 0.84 wt. %, 1.1 wt. %, 1.3 wt. %, 1.6 wt. %, 1.8 wt. %, 2.1 wt. %, 2.3 wt. %, 2.6 wt. %, 2.8 wt. %, 3 wt. %, 3.3 wt. %, 3.5 wt. %, 3.8 wt. %, 4 wt. %, 4.3 wt. %, 4.5 wt. %, 4.8 wt. %, 5 wt. %, 6 wt. %, 6.5 wt. %, 7 wt. %, 7.5 wt. %, 8 wt. %, 8.5 wt. %, 9 wt. %, 9.5 wt. %, or 10 wt. %. Alternatively, in certain embodiments, the explosive mixture may not comprise any inhibitors.
In certain embodiments, the treatment component of the explosive formulation used in the method of the second aspect of the invention comprises a reaction status reporter. The reaction status reporter is capable of indicating the progress of the oxidation of the oxidizable material in the blast hole by the oxidant of the treatment component. The reaction status reporter may be, for example, a pH indicator or a redox indicator. The reaction status reporter may be present in the treatment component at a concentration of from about 0.01 wt. % to about 10 wt. %, or from about 0.028 wt. % to about 10 wt. %, about 0.046 wt. % to about 10 wt. %, about 0.064 wt. % to about 10 wt. %, about 0.082 wt. % to about 10 wt. %, about 0.1 wt. % to about 10 wt. %, about 0.59 wt. % to about 10 wt. %, about 1.1 wt. % to about 10 wt. %, about 1.6 wt. % to about 10 wt. %, about 2.1 wt. % to about 10 wt. %, about 2.6 wt. % to about 10 wt. %, about 3 wt. % to about 10 wt. %, about 3.5 wt. % to about 10 wt. %, about 4 wt. % to about 10 wt. %, about 4.5 wt. % to about 10 wt. %, about 5 wt. % to about 10 wt. %, about 0.01 wt. % to about 9.5 wt. %, about 0.01 wt. % to about 9 wt. %, about 0.01 wt. % to about 8.5 wt. %, about 0.01 wt. % to about 8 wt. %, about 0.01 wt. % to about 7.5 wt. %, about 0.01 wt. % to about 7 wt. %, about 0.01 wt. % to about 6.5 wt. %, about 0.01 wt. % to about 6 wt. %, about 0.01 wt. % to about 5.5 wt. %, about 0.01 wt. % to about 5 wt. %, about 0.1 wt. % to about 5 wt. %, about 1.1 wt. % to about 5 wt. %, about 2.1 wt. % to about 5 wt. %, about 3 wt. % to about 5 wt. %, about 4 wt. % to about 5 wt. %, about 0.1 wt. % to about 4 wt. %, about 0.1 wt. % to about 3 wt. %, about 0.1 wt. % to about 2.1 wt. %, or about 0.1 wt. % to about 1.1 wt. %. It may be greater than or equal to about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.59 wt. %, 1.1 wt. %, 1.6 wt. %, or 2.1 wt. %. It may be less than or equal to about 10 wt. %, 9.5 wt. %, 9 wt. %, 8.5 wt. %, 8 wt. %, 7.5 wt. %, 7 wt. %, 6.5 wt. %, 6 wt. %, 5.5 wt. %, 5 wt. %, 4.5 wt. %, 4 wt. %, 3.5 wt. %, or 3 wt. %. In certain embodiments, it may be, for example, about 0.01 wt. %, 0.019 wt. %, 0.028 wt. %, 0.037 wt. %, 0.046 wt. %, 0.055 wt. %, 0.064 wt. %, 0.073 wt. %, 0.082 wt. %, 0.091 wt. %, 0.1 wt. %, 0.34 wt. %, 0.59 wt. %, 0.84 wt. %, 1.1 wt. %, 1.3 wt. %, 1.6 wt. %, 1.8 wt. %, 2.1 wt. %, 2.3 wt. %, 2.6 wt. %, 2.8 wt. %, 3 wt. %, 3.3 wt. %, 3.5 wt. %, 3.8 wt. %, 4 wt. %, 4.3 wt. %, 4.5 wt. %, 4.8 wt. %, 5 wt. %, 6 wt. %, 6.5 wt. %, 7 wt. %, 7.5 wt. %, 8 wt. %, 8.5 wt. %, 9 wt. %, 9.5 wt. %, or 10 wt. %.
In certain embodiments of the method of the second aspect of the invention, the blast hole is charged with a non-explosive fluid, optionally water, until sufficiently cool prior to, or during step a). In certain embodiments, the blast hole may be cooled to a temperature of from about 10° C. to about 80° C., or from about 12° C. to about 80° C., about 14° C. to about 80° C., about 16° C. to about 80° C., about 18° C. to about 80° C., about 20° C. to about 80° C., about 23° C. to about 80° C., about 26° C. to about 80° C., about 29° C. to about 80° C., about 32° C. to about 80° C., about 35° C. to about 80° C., about 38° C. to about 80° C., about 41° C. to about 80° C., about 44° C. to about 80° C., about 47° C. to about 80° C., about 50° C. to about 80° C., about 10° C. to about 77° C., about 10° C. to about 74° C., about 10° C. to about 71° C., about 10° C. to about 68° C., about 10° C. to about 65° C., about 10° C. to about 62° C., about 10° C. to about 59° C., about 10° C. to about 56° C., about 10° C. to about 53° C., about 10° C. to about 50° C., about 20° C. to about 50° C., about 26° C. to about 50° C., about 32° C. to about 50° C., about 38° C. to about 50° C., about 44° C. to about 50° C., about 20° C. to about 44° C., about 20° C. to about 38° C., about 20° C. to about 32° C., or about 20° C. to about 26° C. It may be cooled to a temperature less than or equal to about 80° C., 77° C., 74° C., 71° C., 68° C., 65° C., 62° C., 59° C., 56° C., 53° C., 50° C., 47° C., 44° C., 41° C., or 38° C. In certain embodiments, it may be, for example, about 10° C., 11° C., 12° C., 13° C., 14° C., 15° C., 16° C., 17° C., 18° C., 19° C., 20° C., 22° C., 23° C., 24° C., 26° C., 28° C., 29° C., 30° C., 32° C., 34° C., 35° C., 36° C., 38° C., 40° C., 41° C., 42° C., 44° C., 46° C., 47° C., 48° C., 50° C., 56° C., 59° C., 62° C., 65° C., 68° C., 71° C., 74° C., 77° C., or 80° C.
In certain embodiments of the method of the second aspect of the invention, step b) is performed at a time after step a), preferably of from about 1 hour to about 5 days, until most or all or a sufficient amount of the oxidisable material which is contactable with the treatment component of the explosive formulation used in the method of the second aspect of the invention has been oxidised. In certain embodiments, the time may be from about 30 min to about 2 weeks, or from about 36 min to about 2 weeks, about 42 min to about 2 weeks, about 48 min to about 2 weeks, about 54 min to about 2 weeks, about 1 h to about 2 weeks, about 18 h to about 2 weeks, about 1.4 days to about 2 weeks, about 2.1 days to about 2 weeks, about 2.8 days to about 2 weeks, about 3.5 days to about 2 weeks, about 4.2 days to about 2 weeks, about 4.9 days to about 2 weeks, about 5.6 days to about 2 weeks, about 6.3 days to about 2 weeks, about 1 week to about 2 weeks, about 30 min to about 1.9 weeks, about 30 min to about 1.8 weeks, about 30 min to about 1.7 weeks, about 30 min to about 1.6 weeks, about 30 min to about 1.5 weeks, about 30 min to about 1.4 weeks, about 30 min to about 1.3 weeks, about 30 min to about 1.2 weeks, about 30 min to about 1.1 weeks, about 30 min to about 1 week, about 1 h to about 1 week, about 1.4 days to about 1 week, about 2.8 days to about 1 week, about 4.2 days to about 1 week, about 5.6 days to about 1 week, about 1 h to about 5.6 days, about 1 h to about 4.2 days, about 1 h to about 2.8 days, or about 1 h to about 1.4 days. It may be greater than or equal to about 30 min, 33 min, 36 min, 39 min, 42 min, 45 min, 48 min, 51 min, 54 min, 57 min, 1 h, 18 h, 1.4 days, 2.1 days, or 2.8 days. It may be less than or equal to about 2 weeks, 1.9 weeks, 1.8 weeks, 1.7 weeks, 1.6 weeks, 1.5 weeks, 1.4 weeks, 1.3 weeks, 1.2 weeks, 1.1 weeks, 1 week, 6.3 days, 5.6 days, 4.9 days, or 4.2 days. In certain embodiments, it may be, for example, about 30 min, 33 min, 36 min, 39 min, 42 min, 45 min, 48 min, 51 min, 54 min, 57 min, 1 h, 9.4 h, 18 h, 1.1 days, 1.4 days, 1.8 days, 2.1 days, 2.5 days, 2.8 days, 3.2 days, 3.5 days, 3.9 days, 4.2 days, 4.6 days, 4.9 days, 5.3 days, 5.6 days, 6 days, 6.3 days, 6.7 days, 1 week, 1.2 weeks, 1.3 weeks, 1.4 weeks, 1.5 weeks, 1.6 weeks, 1.7 weeks, 1.8 weeks, 1.9 weeks, or 2 weeks.
In certain embodiments of the method of the second aspect of the invention, the method further comprises a step of: monitoring the progress of oxidation of the oxidisable material prior to step b). The monitoring may, for example, comprise measuring a pH, oxidation reduction potential (ORP), iron (III) concentration, absorbance (e.g. UV-visible light absorbance), emission (e.g. UV-visible light emission), colour change (i.e. colorimetry), or sulphate concentration.
In certain embodiments of the method of the second aspect of the invention, the method comprises the steps of:
In certain embodiments of the method of the second aspect of the invention, the method comprises the following steps:
In certain embodiments of the method of the second aspect of the invention, the treatment component of the explosive formulation used in the method of the second aspect of the invention comprises one or more of the following:
In certain embodiments, the treatment component of the explosive formulation used in the method of the second aspect of the invention comprises one or more of the following:
In certain embodiments, the method of the second aspect comprises the following steps:
In certain embodiments, the method of the second aspect comprises the following steps:
In a third aspect of the invention there is provided a system for loading a blast hole in reactive ground with an explosive formulation of the first aspect of the invention described herein, the system comprising:
The blast hole, reactive ground, explosive formulation, treatment component of the explosive formulation and blasting component of the explosive formulation may be as hereinbefore described with respect to the first aspect and second aspect of the invention.
The system of the third aspect may comprise the explosive formulation of the first aspect of the invention described herein and may be used to perform the method of the second aspect of the invention described herein. The method of the second aspect of the invention described herein may be performed using the system of the third aspect of the invention described herein.
In a fourth aspect of the invention there is provided a kit for loading a blast hole in reactive ground with an explosive formulation, the kit comprising:
The blast hole, reactive ground, explosive formulation, treatment component of the explosive formulation and blasting component of the explosive formulation may be as hereinbefore described with respect to the first aspect and second aspect of the invention described herein.
The kit of the fourth aspect may comprise the explosive formulation of the first aspect of the invention described herein and may be used to perform the method of the second aspect of the invention described herein. The method of the second aspect may be performed using the kit of the fourth aspect.
The kit of the fourth aspect may be one or more components of the system of the third aspect of the invention described herein. The system of the third aspect may incorporate the kit of the fourth aspect of the invention described herein.
In a fifth aspect of the invention there is provided the explosive formulation according to the first aspect of the invention described herein, for use in blasting a reactive ground, optionally a hot reactive ground.
In a sixth aspect of the invention there is provided use of the explosive formulation according to the first aspect of the invention described herein for the manufacture of a product for blasting a reactive ground, optionally a hot reactive ground.
In describing and claiming the present invention, the following terminology will be used in accordance with the definitions set out below. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only and is not intended to be limiting.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one having ordinary skill in the art to which the invention pertains.
Unless the context clearly requires otherwise, throughout the description and the claims, the terms “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. For example, a formulation, composition, component, mixture, process or method that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such formulation, composition, component, mixture, process or method.
The transitional phrase “consisting of” excludes any element, step, or ingredient not specified. If in the claim, such would close the claim to the inclusion of materials other than those recited except for impurities ordinarily associated therewith. When the phrase “consisting of” appears in a clause of the body of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole.
The transitional phrase “consisting essentially of” is used to define a formulation, component, composition, process or method that includes materials, steps, features, (sub)components, or elements, in addition to those literally disclosed, provided that these additional materials, steps, features, (sub)components, or elements do not materially affect the basic and novel characteristic(s) of the claimed invention. The term “consisting essentially of” occupies a middle ground between “comprising” and “consisting of”.
Where applicants have defined an invention or a portion thereof with an open-ended term such as “comprising”, it should be readily understood that (unless otherwise stated) the description should be interpreted to also describe such an invention using the terms “consisting essentially of” or “consisting of”. In other words, with respect to the terms “comprising”, “consisting of”, and “consisting essentially of”, where one of these three terms is used herein, the presently disclosed and claimed subject matter may include the use of either of the other two terms. Thus, in some embodiments not otherwise explicitly recited, any instance of “comprising” may be replaced by “consisting of” or, alternatively, by “consisting essentially of”.
Other than in the operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients or reaction conditions used herein are to be understood as modified in all instances by the term “about”. The examples are not intended to limit the scope of the invention. In what follows, or where otherwise indicated, “%” will mean “weight %”, “ratio” will mean “weight ratio” and “parts” will mean “weight parts”.
The terms “predominantly”, “predominant”, and “substantially” as used herein shall mean comprising more than 50% by weight, unless otherwise indicated.
As used herein, with reference to numbers in a range of numerals, the terms “about,” “approximately” and “substantially” are understood to refer to the range of −10% to +10% of the referenced number, preferably −5% to +5% of the referenced number, more preferably −1% to +1% of the referenced number, most preferably −0.1% to +0.1% of the referenced number. Moreover, with reference to numerical ranges, these terms should be construed as providing support for a claim directed to any number or subset of numbers in that range. For example, a disclosure of from 1 to 10 should be construed as supporting a range of from 1 to 8, from 3 to 7, from 1 to 9, from 3.6 to 4.6, from 3.5 to 9.9, from 8 to 10, and so forth.
The terms “preferred” and “preferably” refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.
As used herein, the term “hot ground” means a ground or rock material that has a temperature of 55° C. or more.
As used herein, the term “reactive ground” means a ground or rock that undergoes a spontaneous exothermic reaction after it comes into contact with a nitrate. The reaction of concern typically involves the chemical oxidation of sulphides (usually of iron or copper) by nitrates and the liberation of potentially large amounts of heat. The process can be unpredictable and so violent that it results in mass explosions.
In certain embodiments, the term “reactive ground” means a ground which contains an average metal sulfide concentration of at least about 0.5 wt. %, 1 wt. %, 2 wt. %, or 5 wt. % in the region where a blast hole is drilled, or is to be drilled. In other words, the material excavated when drilling a blast hole in reactive ground contains an average metal sulfide concentration of at least about 0.5 wt. %, 1 wt. %, 2 wt. %, or 5 wt. %. Alternatively, in the case where a blast hole has already been drilled, the ground will be a reactive ground if ground samples taken from the inner surface of said blast hole contain an average metal sulfide concentration of at least about 0.5 wt. %, 1 wt. %, 2 wt. %, or 5 wt. %.
As used herein, the term “blast hole” should be construed broadly to include a hole which has been drilled into a ground which is to be loaded with one or more explosives, as well as a natural hole or fissure in ground which is to be loaded with one or more explosives.
AN: Ammonium nitrate; EDTA: ethylenediaminetetraacetic acid; ORP: Oxidation-Reduction Potential; SN: sodium nitrate.
Preferred features, embodiments and variations of the invention may be discerned from the following Examples which provides sufficient information for those skilled in the art to perform the invention. The following Examples are not to be regarded as limiting the scope of the preceding Summary of the Invention in any way.
15 g of finely ground pyrite and 135 g of finely ground sand were mixed together to create a 10% (w/w) pyrite-containing “rock sample” for testing against the pre-treatment solutions.
10 g of the 10% pyrite-containing rock sample (or in the case of the experiments with samples from reactive ground: 10 g of the reactive ground sample) was added to each sample jar and the solution being trialed was added to this until the sample jar was filled to the 100 mL mark. Samples were mixed well by shaking and allowed to settle (with loose lids to allow for potential gas release).
pH and Oxidation-Reduction Potential (ORP) measurements were taken initially and after 24 hours at 40° C. along with photos to allow for visual observation and comparison. Samples were left at 40° C. for 3 more days then moved to 70° C. for a week (11 days total) unless otherwise stated.
10 g of sand (rather than the pyrite-containing rock sample) was added to the sample jar, and water was added until the sample jar was filled to the 100 mL mark. The results are summarised in Table 1 below, and the associated images over a period of time after mixing the solution with the sand are shown at
The general experimental procedure was followed using water as the solution being trialed. The results are summarised in Table 2 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using a 10% (w/v) ammonium nitrate aqueous solution as the solution being trialed. The results are summarised in Table 3 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The experimental results suggested that the ammonium nitrate solution was able to oxidise the pyrite in the rock sample that was accessible to the solution.
The general experimental procedure was followed using a 1% (w/v) H2O2 aqueous solution as the solution being trialed. The results are summarised in Table 4 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The experimental results suggested that the hydrogen peroxide solution was able to oxidise the pyrite in the rock sample that was accessible to the solution.
The general experimental procedure was followed using an aqueous solution adjusted to pH 3 with citric acid as the solution being trialed. The results are summarised in Table 5 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 2% (w/v) EDTA solution as the solution being trialed. The results are summarised in Table 6 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 10% (w/v) AN solution adjusted to pH 3 with citric acid as the solution being trialed. The results are summarised in Table 7 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 10% (w/v) SN solution as the solution being trialed. The results are summarised in Table 8 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The experimental results suggested that the SN solution was able to oxidise the pyrite in the rock sample that was accessible to the solution.
The general experimental procedure was followed using an aqueous 2% (w/v) Borax solution as the solution being trialed. The results are summarised in Table 9 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 10% (w/v) NaCl solution as the solution being trialed. The results are summarised in Table 10 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 2% (w/v) sodium percarbonate solution as the solution being trialed. The results are summarised in Table 11 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The experimental results suggested that the sodium percarbonate solution was able to oxidise the pyrite in the rock sample that was accessible to the solution.
The general experimental procedure was followed using an aqueous 1% (w/v) weathering agent solution (a 6% (w/w) FeSO4·6H2O, 13.89% (w/w) Fe2(SO4)3·9H2O aqueous solution) as the solution being trialed. The results are summarised in Table 12 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 1% (w/v) weathering agent (a 6% (w/w) FeSO4·6H2O, 13.89% (w/w) Fe2(SO4)3·9H2O aqueous solution) and 10% (w/v) AN solution as the solution being trialed. The results are summarised in Table 13 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 2% (w/v) citric acid solution as the solution being trialed. The results are summarised in Table 14 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The experimental results suggested that the citric acid chelates Fe ions from the pyrite to form the yellow coloured complex.
The general experimental procedure was followed using an aqueous 2% (w/v) citric acid and 2% (w/v) borax solution (a pyrite solubilizing agent) as the solution being trialed. The results are summarised in Table 15 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 10% (w/v) AN and 2% (w/v) borax solution as the solution being trialed. The results are summarised in Table 16 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
Without being bound by theory, the inventors postulate that the borate may have precipitated the iron from the pyrite as iron borate, thus preventing formation of iron (III) oxide.
The general experimental procedure was followed using an aqueous 2% (w/v) citric acid, 10% (w/v) AN and 2% (w/v) borax solution as the solution being trialed. The results are summarised in Table 17 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
Without being bound by theory, the inventors postulate that the borate and/or citrate may have chelated the iron from the pyrite, thus preventing formation of iron (III) oxide.
The general experimental procedure was followed using an aqueous 2% (w/v) citric acid and 2% (w/v) EDTA solution as the solution being trialed. The results are summarised in Table 18 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 10% (w/v) AN and 2% (w/v) EDTA solution as the solution being trialed. The results are summarised in Table 19 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The experimental results suggested that the AN and EDTA solution was able to oxidise the pyrite in the rock sample that was accessible to the solution.
The general experimental procedure was followed using an aqueous 10% (w/v) AN, 2% (w/v) EDTA, and 2% (w/v) citric acid solution as the solution being trialed. The results are summarised in Table 20 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
Without being bound by theory, the inventors postulate that the EDTA may have chelated the iron from the pyrite, thus preventing formation of iron (III) oxide.
The general experimental procedure was followed using an aqueous 10% (w/v) SN and 2% (w/v) citric acid solution as the solution being trialed. The results are summarised in Table 21 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
Without being bound by theory, the inventors postulate that the citrate may have chelated the iron from the pyrite, thus preventing formation of iron (III) oxide.
The general experimental procedure was followed using an aqueous 0.1% (w/v) hydrogen peroxide solution as the solution being trialed. The solution was kept at room temperature over three days. The results are summarised in Table 22 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The experimental results suggested that the hydrogen peroxide solution was able to oxidise the pyrite in the rock sample that was accessible to the solution.
The general experimental procedure was followed using an aqueous 1% (w/v) hydrogen peroxide and citric acid (adjusted to pH 4) solution as the solution being trialed. The solution was kept at room temperature over three days. The results are summarised in Table 23 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 1% (w/v) hydrogen peroxide and 2% (w/v) EDTA solution as the solution being trialed. The solution was kept at room temperature over three days. The results are summarised in Table 24 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 5% (w/v) sodium nitrate, 5% (w/v) sodium nitrite, and citric acid (adjusted to pH 5) solution as the solution being trialed. The solution was kept at room temperature over three days. The results are summarised in Table 25 below, and the associated images over a period of time after mixing the solution with the pyrite-containing rock sample are shown at
The general experimental procedure was followed using an aqueous 10% (w/v) AN solution as the solution being trialed, and a reactive ground rock sample. The solution was kept at room temperature over three days. The results are summarised in Table 26 below, and the associated images over a period of time after mixing the solution with the reactive ground sample are shown at
The general experimental procedure was followed using an aqueous 1% (w/v) hydrogen peroxide solution as the solution being trialed, and a reactive ground rock sample. The solution was kept at room temperature over three days. The results are summarised in Table 27 below, and the associated images over a period of time after mixing the solution with the reactive ground sample are shown at
The general experimental procedure was followed using an aqueous 2% (w/v) EDTA solution as the solution being trialed, and a reactive ground rock sample. The solution was kept at room temperature over three days. The results are summarised in Table 28 below, and the associated images over a period of time after mixing the solution with the reactive ground sample are shown at
A 90 g ore sample from a copper mine containing pyrite was mixed with 90 g of sodium nitrate, 45 g of citric acid and 450 mL of water. A control experiment was performed where another sample of the same ore was mixed with 450 mL of water. Both samples were held at 70° C. for 48 hours. Thereafter, the solid was collected and dried. Standard AEISG code isothermal reactive ground tests (as described in Appendix 2 of the Australian Explosives Industry and Safety Group Inc (AEISG) Code of Practice Elevated Temperature and Reactive Ground: Version 1.1 Mar. 2007) were performed on the control and test sample, i.e. 18 g of each sample was mixed with 18 g of ammonium nitrate and 4 g of a weathering solution (made by dissolving 3 g of FeSO4·7H2O in 22 g distilled water; dissolving 5 g of Fe2(SO4)3·9H2O in 13 g distilled water; and combining 2 g of the FeSO4 solution with 2 g of the Fe2(SO4)3). The mixtures were monitored for 48 hrs while being held at 70° C. The results, shown in
A 90 g 10% (w/w) pyrite in sand mixture was mixed with 90 g of sodium nitrate, 45 g of citric acid and 450 mL of water. A control experiment was performed where 90 g 10% (w/w) pyrite in sand mixture was mixed with 450 mL of water. Both samples were held at 70° C. for 48 hours. Thereafter, the solid was collected and dried. Standard AEISG code isothermal reactive ground tests (as described in Appendix 2 of the Australian Explosives Industry and Safety Group Inc (AEISG) Code of Practice Elevated Temperature and Reactive Ground: Version 1.1 Mar. 2007) were performed on the control and test sample, i.e. 18 g of each sample was mixed with 18 g of ammonium nitrate and 4 g of a weathering solution (made by dissolving 3 g of FeSO4·7H2O in 22 g distilled water; dissolving 5 g of Fe2(SO4)3·9H2O in 13 g distilled water; and combining 2 g of the FeSO4 solution with 2 g of the Fe2(SO4)3). The mixtures were monitored for 48 hrs while being held at 160° C. The results, shown in
As shown in
Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms. In particular, features of any one of the various described examples may be provided in any combination in any of the other described examples. Various modifications and alterations to this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that this invention is not intended to be unduly limited by the illustrative embodiments and examples set forth herein and that such examples and embodiments are presented by way of example only with the scope of the invention intended to be limited only by the claims set forth herein as follows.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022903765 | Dec 2022 | AU | national |
