Title of Invention

"AN EMULSION COMPOSITION USEFUL FOR BLASTING HARD STRATA EXCAVATION WORK"

Abstract

An emulsion composition useful for blasting hard strata excavation work In the present invention there is provided a novel composition for hard strata excavation work, which consists of oxidizing and reducing ingredients, emulsifier, gassing agent(s) to produce zero oxygen balance and composition suitable as bulk emulsion explosive. In the composition sugar is present in the mixture of oxidizing agents and the gassing agent is a mixture of sodium nitrite and potassium pyro antimonate. The explosive composition is useful as chargeable to blast holes for safe blasting in surface mine and other excavation works. It is a booster sensitive bulk emulsion chargeable to the blasting hole directly and can play an important role in achieving the objective of blasting in surface mining including coal, metal, dams and other excavation projects.

Full Text

This invention relates to an emulsion composition useful for blasting hard strata excavation work. This invention particularly relates to a novel emulsion composition useful for blasting of hard strata, such as excavation works for surface coal and non-coal mines. The present invention more particularly relates to a novel emulsion composition which is not a mere admixture but a synergistic mixture having physical and explosive properties of the bulk emulsion explosive which are distinct and different from the aggregation of properties of the individual ingredients and is a booster sensitive bulk emulsion explosive composition chargeable to blast hole. Emulsion explosives, commonly water-in-oil emulsions, provide high interfacial contact between oxidizer and fuel, resulting in a high degree of sensitivity and high rate of reactivity without the use of any molecular explosive. The unique property of emulsion explosive is its high velocity of detonation (VOD) ranging from 4000-6000 m/s. This results in high detonation pressure and brisance effect which helps in improving rock fragmentation. The fuel phase being water immiscible, these explosives are water resistant and insensitive to impact and fire. For heavy blasting, site mixed emulsion used as bulk explosives is used in surface blasting. Bulk emulsion having high velocity of detonation, poor sensitive to impact, high explosion energy, good shuttering effect and cheap in the cost is suitable as bulk emulsion explosives. The main drawback of non-cap sensitive bulk emulsion explosives are loosing of explosive material, crystallization of oxidizing agents, breaking of the emulsion lattice, separation of oxidizing and fuel phase, increasing of the density, poor water resistance, misfires, having very poor shelf life poor shuttering effect. Reference may be made to US patent No. 5,500,062, titled: emulsion explosive, wherein a mixed surfactant system have been used in emulsion explosives for improving emulsion stability to comprise a surfactant and a co-surfactant, each having branched chain hydrocarbyl tail groups, the former having significantly longer tail chain groups than the latter, for which system poly[alk(en)yl] succinic anhydride based surfactants are especially preferred, said surfactants having an interaction parameter. Emulsion explosives have been described by, for example, Bluhm in U.S. patent No.: 3,447,978 which discloses a composition comprising an aqueous discontinuous phase containing dissolved oxygen-supplying salts, a carbonaceous fuel continuous phase, an occluded gas and a water-in-oil emulsifier. Cattermole et al., in U.S. patent No. 3,674,578, describe a similar composition containing as part of the inorganic oxidizer phase, a nitrogen-base salt such as an amine nitrate. Tomic, in U.S. patent No. 3,770,522 also describes a similar composition wherein the emulsifier is an alkali metal or ammonium stearate. Healy, in U.S. patent No. 4,248,644, describes an emulsion explosive wherein the oxidizer salt is added to the emulsion as a melt to form a "melt-in-fuel" emulsion. McKenzie in U.S. patent No. 4,931,110 describes the use of a bis(alkanolamine or polyol) amide and/or ester derivatives of, for example, polyalk(en)yl succinic anhydride compounds as suitable surfactants. Polyalk(en)yl succinic anhydride compounds were described by Baker in Canadian patent No. 1,244,463. Forsberg et al. in U.S. patent No. 4,840,687, describe an emulsion explosive composition wherein the emulsifier is a nitrogen-containing emulsifier derived from at least one carboxylic acylating agent, a polyamine, and an acidic compound. Riga, et al. U.S. patent no. 5,527,491 dated June 18, 1996 have disclosed emulsifier which comprise the reaction product of component (I) with component (II). Component (I) comprises the reaction product of certain carboxylic acids or anhydrides, or ester or amide derivatives thereof, with ammonia, at least one amine, at least one alkali and/or at least one alkaline-earth metal. Component (II) comprises certain phosphorus-containing acids; or metal salts of said phosphorus-containing acids, the metals being selected from the group consisting of magnesium, calcium, strontium, chromium, manganese, iron, molybdenum, cobalt, nickel, copper, silver, zinc, cadmium, aluminum, tin, lead, and mixtures of two or more thereof. These emulsifiers are useful in water-in-oil explosive emulsions. Reference may also be made to U.S. patent no. 5,639,988 for an explosive composition, which includes a hydrocarbyl polyamine emulsifier, characterised by a straight link between the hydrocarbyl group and said polyamine. A method of forming the composition is also provided, characterised by the emulsifier being produced by reacting an alkanolamine with a hydrocarbyl halide. Coupland, et al. U.S. patent no. 5,859,264 January 12, 1999 have studied about the Gamma and delta lactones of formulae (I and 11) are used as emulsifiers in explosive compositions comprising a continuous organic phase and a discontinuous aqueous phase containing an oxygen-supplying compound. Janke et. al. have described in his U.S. patent no. 5,920,031 about water in oil emulsion, which are useful in explosives. These emulsions comprise: a discontinuous aqueous phase comprising at least one oxygen-supplying component; a continuous organic phase comprising at least one carbonaceous fuel; and a minor emulsifying amount of at least one emulsifier. The emulsifier is the product made by the reaction of component (A) with component (B), component (A) being at least one substituted succinic acylating agent, said substituted succinic acylating agent consisting of substituent groups and succinic groups wherein the substituent groups are derived from a polyalkene, said acylating agents being characterized by the presence within their structure of an average of at least 1.3 succinic groups for each equivalent weight of substituent groups, and component (B) being ammonia and/or at least one mono-amine. Reference may be made to U.S. patent no. 6,200,398, for water in oil emulsion explosive composition. Water in oil emulsion explosive compositions comprises a discontinuous aqueous phase comprising at least one oxygen-supplying component, a continuous organic phase, an emulsifying amount of an emulsifier composition comprising: the reaction product of an amine (C) characterized by the presence within its structure of at least one H--N group and an intermediate formed in the reaction of (A) at least one olefinic compound containing at least one group of the formula ##STR1## and (B) at least one carboxylic reactant selected from the group consisting of compounds of the formula R.sup.3 C(0)(R.sup.4).sub.n C(0)OR.sup.5 (III) wherein each of R.sup.3 and R.sup.5 is independently H or a hydrocarbyl group, R.sup.4 is a divalent hydrocarbylene group, and n is 0 or 1, and reactive sources thereof and optionally, from about 0.5 to about 2 moles, per mole of (B), of (D) at least one aldehyde or ketone; and optionally a sensitizer. Venter, et al. have described emulsion explosives in U.S. patent no. 6,478,904 dated November 12, 2002. An emulsifier comprising at least one ester of a polyhydric composition and a mono-or poly-basic organic acid, the polyhydric composition preferably comprising a sorbitol and/or sorbitan derivative and the acid PIBSA. From a survey of the hitherto known prior art as detailed above, it is seen that the above compositions do not contain potassium pyro antimonate as gassing agent and sugar as oxidizing agent. Market survey reveals that there is a requirement of a non-cap sensitive emulsion explosive suitable for rock blasting which is stable, having good shelf life, cheaper and safe. The main object of the present invention is to provide a composition for hard strata excavation work, such as excavation works, blasting of coal and non-coal surface mines. Yet another object of the present invention is to provide an explosive composition, which utilizes oxidizing and reducing ingredients, emulsifier, gassing agent(s) to produce zero oxygen balance and composition suitable as bulk emulsion explosive. Still another object of the present invention is to provide an explosive composition, which contains potassium pyro antimonate as a gassing agent and sugar as an oxidizing agent. Still yet another object of the present invention is to provide an explosive composition which would be chargeable to blast hole, releasing large amount of explosion energy for safe blasting in surface mines and other excavation works. A further object of the present invention is to provide an explosive composition which is not a mere admixture but a synergistic mixture having physical and explosive properties of the bulk emulsion explosive which are distinct and different from the aggregation of properties of the individual ingredients. In the present invention there is provided a novel composition for hard strata excavation work, which consists of oxidizing and reducing ingredients, emulsifier, gassing agent(s) to produce zero oxygen balance and composition suitable as bulk emulsion explosive. In the composition sugar is present in the mixture of oxidizing agents and the gassing agent is a mixture of sodium nitrite and potassium pyro antimonate. The explosive composition is useful as chargeable to blast holes for safe blasting in surface mine and other excavation works. It is a booster sensitive bulk emulsion chargeable to the blasting hole directly and can play an important role in achieving the objective of blasting in surface mining including coal, metal, dams and other excavation projects. Accordingly the present invention provides an emulsion composition useful for blasting hard strata excavation work, which comprises: (1) Oxidizing agents : 94.52 to 96.00 wt.%; (2) Reducing agents : 2.80 to 3.98 wt.%; (3) Emulsifier : 1.20 to 1.50 wt.%; (4) Gassing agents : 1.10 to 2.00 wt.% of (1) + (2) + (3). In an embodiment of the present invention the oxidizing agents is a mixture of ammonium nitrate, water, gum and sugar. In another embodiment of the present invention the ammonium nitrate used is such as lump, prill or mixture thereof. In yet another embodiment of the present invention the reducing agent is such as diesel, furnace oil or mixture thereof. In still another embodiment of the present invention the emulsifier is such as sorbitan mono oleate. In still yet another embodiment of the present invention the gassing agent (s) is such as a mixture of sodium nitrite and potassium pyro antimonate. In a further another embodiment of the present invention the oxidizing agent (s), reducing agent (s) and emulsifier are of commercial grade. In a yet further embodiment of the present invention the gassing agent (s) is of 99% purity. In a still further embodiment of the present invention the composition consists of: 1) Oxidizing agent (s) 94.52 to a) Ammonium Nitrate 76.86 to b) Water 14.97 to c)Gum 0.10 to d) Sugar 2.00 to 2) Reducing agent (s) 2.80 to a) Diesel 1.40 to b) Furnace Oil 1.40 to 3) Emulsifier 1.20 to a) Sorbiton Mono Oleate 1.20 to 4) Gassing agent (s) 1.10 to 96.00 wt.%; wherein : 77.90 wt.%; 16.00 wt.%; 0.20 wt.%; 2.49 wt.%; 3.98 wt.%; wherein : 1.98 wt.%; 1.99 wt.%; 1.50 wt.%; wherein : 1.50 wt.%; 2.00 wt.% of (1) + (2) + (3); wherein : a) Sodium Nitrite (20% solution) 10 to 15 ml / kg of (1) + (2) + (3); b) Potassium pyro antimonate 1 to 5 gm / kg of (1) + (2) + (3). In a still yet further embodiment of the present invention the composition consists of: (1) Oxidizing agent (s) 94.52 wt.%; (2) Reducing agent (s) 3.98 wt.%; (3) Emulsifier 1.50 wt.%; (4) Gassing agent (s) 1.10 wt.% of (1) + (2) + (3). In another embodiment of the present invention the composition consists of: (1) Oxidizing agent (s) 94.52 wt.%; wherein : (a) Ammonium Nitrate 76.86 wt.%; (b) Water 14.97 wt.%; (c) Gum 0.20 wt.%; (d) Sugar 2.49 wt.%; (2) Reducing agent (s) 3.98 wt.%; wherein : (a) Diesel 1.99 wt.%; (b) Furnace Oil 1.99 wt.%; (3) Emulsifier 1.50 wt.%; wherein : (a) Sorbiton Mono Oleate 1.50 wt.%; (4) Gassing agent (s) 1.10 wt.% of (1) + (2) + (3); wherein : (a) Sodium Nitrite (20% solution) 10 ml / kg of (1) + (2) + (3); (b) Potassium pyro antimonate 1 gm / kg of (1) + (2) + (3). In still another embodiment of the present invention the composition consists of: (1) Oxidizing agent (s) 96.00 wt.%; (2) Reducing agent (s) 2.80 wt.%; (3) Emulsifier 1.20 wt.%; (4) Gassing agent (s) 2.00 wt.% of (1) + (2) + (3). n yet another embodiment of the present invention the composition consists of: 1) Oxidizing agent (s) 96.00 wt.%; wherein ; a) Ammonium Nitrate 77.90 wt.%; b) Water 16.00 wt.%; c)Gum 0.10 wt.%; d) Sugar 2.00 wt.%; 2) Reducing agent (s) 2.80 wt.%; wherein : a) Diesel 1.40 wt.%; b) Furnace Oil 1.40 wt.%; 3) Emulsifier 1.20 wt.%; wherein : a) Sorbiton Mono Oleate 1.20 wt.%; 4) Gassing agent (s) 2.00 wt.% of (1) + (2) + (3); wherein : a) Sodium Nitrite (20% solution) 15 ml / kg of (1) + (2) + (3); b) Potassium pyro antimonate 5 gm / kg of (1) + (2) + (3). In still another embodiment of the present invention the composition providing improved oil absorption and increased energy output consists of a mixture of 10 :o 20 wt.% ammonium nitrate prill and 20 to 40 wt.% flake grade aluminium powder. It is a feature of the present invention that the composition is not a mere admixture but a synergistic mixture having physical and explosive properties of the bulk emulsion explosive which are distinct and different from the aggregation of properties of the individual ingredients. The present invention provides a novel composition for hard strata excavation work, which contains oxidizing and reducing ingredients, emulsifier, gassing agent(s) to produce zero oxygen balance and composition suitable as bulk emulsion explosive useful as chargeable to blast holes for safe and efficient blasting in surface mine and other excavation works. It is a booster sensitive bulk emulsion chargeable to the blasting hole directly and can play an important role in achieving the objective of blasting in surface mining including coal, metal, dams and other excavation projects. The novel composition of the present invention has been obtained by the non-obvious inventive steps of providing a combination such as herein above described of oxidizing and reducing ingredients, emulsifier, gassing agent(s) to produce zero oxygen balance, wherein sugar is present in the mixture of oxidizing agents and the gassing agent is a mixture of sodium nitrite and potassium pyro antimonate. The process of making bulk emulsion explosives is divided into two phases, as depicted in the flow chart given in figure 1 of the drawing accompanying this specification. In the first phase, base emulsion matrix having higher density ranging from 1.30 to 1.45 g/cm3 is prepared. The oxidizing agents such as ammonium nitrate (lump), gum and sugar are dissolved in water at a temperature in the range of 60 to70°C in a container (A) to obtain a super saturated solution. The emulsifier, sorbitan mono oleate, reducing agents such as furnace oil and diesel are mixed well in another container (B) and heated at a temperature in the range of 60 to70°C for maximum flow. The super saturated solution of container (A) is slowly mixed with that in container (B) in an emulsifying reactor under stirring at a stirrer speed of above 3000 to 3500 rpm. As the emulsion formation starts, the speed of the stirrer is maintained in between 4000 to 5000 rpm. In this process emulsion matrix having density 1.30 to 1.45 g/cm3 and viscosity 45000 to 65000 cp is prepared. The composition of the base emulsion matrix has a negative oxygen balance (-4.0 to 4.5 g/g approx.). In the second phase, for bulk emulsion explosive chargeable to blast hole, density of base emulsion should be adjusted in the range of 1.0 to 1.5 g/cm3. For reducing the density, providing improved oil absorption and increased energy output a mixture of 10 to 20 wt.% ammonium nitrate prill and 20 to 40 wt.% flake grade aluminium powder is mixed with the help of stirrer at a very slow speed (100 rpm). Ammonium nitrate prill makes the emulsion matrix nearly zero oxygen balance or slightly negative oxygen balance. To the emulsion matrix is added gassing agent, such as a mixture of potassium pyro antimonite and solution of 20% sodium nitrite and temperature is maintained in the range of 45 to 55°C. The speed of mixing is maintained at 1000 to 1500 rpm. The composition prepared is sensitized enough to be initiated with the help of booster. The following examples are given by way of illustration of the present invention in actual practice and should not be construed to limit the scope of the present invention. Example 1 Bulk emulsion explosive chargeable to blast hole and sensitized enough to be initiated with the help of booster was prepared from the composition of the present invention. Commercial grade oxidizing agents: (a) Ammonium Nitrate 76.86 gm; (b) Water 14.97 gm; (C) Gum 0.20 gm; (d) Sugar 2.49 gm; Commercial grade reducing agents: (a) Diesel 1.99 gm; (b) Furnace Oil 1.99 gm; Commercial grade emulsifier Sorbiton Mono Oleate 1.50 gm; Gassing agents of 99% purity: (a) 20% sodium nitrite solution 10.00 ml/Kg; (b) Potassium pyro antimonate 1.00 gm/Kg. The physical and explosive properties of the bulk emulsion explosive chargeable to blast hole and sensitized enough to be initiated with the help of booster as prepared in the above example 1, from the composition of the present invention are given in tables 1 and 2 below. Example 2 Bulk emulsion explosive chargeable to blast hole and sensitized enough to be initiated with the help of booster was prepared from the composition of the present invention. Commercial grade oxidizing agents: (a) Ammonium Nitrate 77.9 gm; (b) Water 16.0 gm; (C) Gum 0.1 gm; (d) Sugar 2.0 gm; Commercial grade reducing agents: (a) Diesel 1.4 gm; (b) Furnace Oil 1.4 gm; Commercial grade emulsifier Sorbiton Mono Oleate 1.2 gm; Gassing agents of 99% purity: (a) 20% sodium nitrite solution 15.00 ml/Kg; (b) Potassium pyro antimonate 5.00 gm/Kg. The physical and explosive properties of the bulk emulsion explosive chargeable to blast hole and sensitized enough to be initiated with the help of booster as prepared in the above example 2, from the composition of the present invention are given in tables 1 and 2 below. The physical and explosive properties of the novel synergistic composition of the present invention are as given in tables 1 and 2 below. Table 1 Physical Properties (Table Removed) Table 2 Explosive Properties (Table Removed) The main advantages of the present invention are: 1. Suitable for hard strata excavation work. 2. Utilizes oxidizing and reducing ingredients, emulsifier, gassing agent(s) to produce zero oxygen balance and composition suitable as bulk emulsion explosive useful as chargeable to blast holes for safe and efficient blasting in surface mine and other excavation works. 3. Is a booster sensitive bulk emulsion chargeable to the blasting hole directly and can play an important role in achieving the objective of blasting in surface mining including coal, metal, dams and other excavation projects. We claim: 1. An emulsion composition useful for blasting hard strata excavation work, which comprises: (1) Oxidizing agents : 94.52 to 96.00 wt.%; (2) Reducing agents : 2.80 to 3.98 wt.%; (3) Emulsifier : 1.20 to 1.50 wt.%; (4) Gassing agents : 1.10 to 2.00 wt.% of (1) + (2) + (3). 2. An emulsion composition as claimed in claim 1, wherein the oxidizing agent is a mixture of ammonium nitrate, water, gum and sugar. 3. An emulsion composition as claimed in claims 1-2, wherein the ammonium nitrate is used as lump, prill or mixture thereof. 4. An emulsion composition as claimed in claims 1-3, wherein the reducing agent is diesel, furnace oil or mixture thereof. 5. An emulsion composition as claimed in claims 1-4, wherein the emulsifier is sorbitan mono oleate. 6. An emulsion composition as claimed in claims 1-5, wherein the gassing agent is a mixture of sodium nitrite and potassium pyro antimonate. 7. An emulsion composition as claimed in claims 1-6, wherein the oxidizing agent, reducing agent and emulsifier are of commercial grade. 8. An emulsion composition as claimed in claims 1-7, wherein the gassing agent is of 99% purity. 13. An emulsion composition as claimed in claims 1-12, wherein the composition consists of: (1) Oxidizing agent 96.00 wt.%; wherein oxidizing agent is (a) Ammonium Nitrate 77.90 wt.%; (b) Water 16.00 wt.%; (c)Gum 0.10 wt.%; (d) Sugar 2.00 wt.%; (2) Reducing agent (s) 2.80 wt.%; wherein reducing agent is (a) Diesel 1.40 wt.%; (b) Furnace Oil 1.40 wt.%; (3) Emulsifier 1.20 wt.%; wherein emulsifier is : (a) Sorbiton Mono Oleate 1.20 wt.%; (4) Gassing agent 2.00 wt.% of (1) + (2) + (3); wherein gassing agent is (a) Sodium Nitrite (20% solution) 15 ml / kg of (1) + (2) + (3); (b) Potassium pyro antimonate 5 gm / kg of (1) + (2) + (3). 14. An emulsion composition as claimed in claims 1-13, wherein the composition providing improved oil absorption and increased energy output consists of a mixture of 10 to 20 wt.% ammonium nitrate prill and 20 to 40 wt.% flake grade aluminium powder.

Documents:

2060-DEL-2004-Abstract-(03-03-2011).pdf

2060-del-2004-abstract.pdf

2060-DEL-2004-Claims-(03-03-2011).pdf

2060-DEL-2004-Claims-(28-02-2012).pdf

2060-del-2004-claims.pdf

2060-DEL-2004-Correspondence Others-(28-02-2012).pdf

2060-DEL-2004-Correspondence-Others-(03-03-2011).pdf

2060-del-2004-correspondence-others.pdf

2060-DEL-2004-Description (Complete)-(03-03-2011).pdf

2060-DEL-2004-Description (Complete)-(07-02-2012).pdf

2060-del-2004-description (complete).pdf

2060-del-2004-drawings.pdf

2060-DEL-2004-Form-1-(03-03-2011).pdf

2060-del-2004-form-1.pdf

2060-del-2004-form-18.pdf

2060-DEL-2004-Form-2-(03-03-2011).pdf

2060-del-2004-form-2.pdf

2060-del-2004-form-3.pdf

2060-del-2004-form-5.pdf