US3770522A

US3770522A - Emulsion type explosive composition containing ammonium stearate or alkali metal stearate

Info

Publication number: US3770522A
Application number: US00243822A
Authority: US
Inventors: E Tomic
Original assignee: EI Du Pont de Nemours and Co
Current assignee: ETI EXPLOSIVES TECHNOLOGIES INTE
Priority date: 1970-08-18
Filing date: 1972-04-13
Publication date: 1973-11-06
Anticipated expiration: 1990-11-06

Abstract

An emulsion type explosive composition containing inorganic oxidizing salt, e.g., ammonium nitrate, water, water-insoluble carbonaceous fuel, e.g., fuel oil, sensitizer, e.g., gas bubbles, and a selected stearate salt emulsifier, e.g., sodium stearate.

Description

United. States Patent 1 Tomic Nov. 6, 1973 EMULSION TYPE EXPLOSIVE COMPOSITION CONTAINING AMMONIUM STEARATE 0R ALKALI METAL STEARATE [75] inventor: Ernst A. Tomic, Wilmington, Del.

[73] Assignee: E. I. Du Pont De Nemours and Company Wilmington, Del.

22 Filed: Apr. 13, 1972 21 Appl. No.: 243,822

Related US. Application Data [63] Continuation-impart of Ser. No. 64,791 Aug. 8, 1970,

abandoned.

[52] HS. C1 149/2, 149/43, 149/44,

149/46 [51] Int. Cl C061) 1/04 [58] Field of Search 149/2, 44, 43, 46

[56] References Cited UNITED STATES PATENTS 7/1938 Pritham 149/44 2,048,050 7/1936 Baker 149/46 X 2,314,807 3/1943 Winning l 149/46 X 3,281,292 10/1966 Falconer et a1. 149/46 X 3,161,551 12/1964 Egly et al..,...... 149/46 3,522,117 7/1970 Atadan et a1. 149/46 X 3,674,578 7/1972 Cattermole et al. 149/2 Primary ExaminerStephen l. Lechert, Jr. Attorney-Samuel S. Blight [57] ABSTRACT 25 Claims, No Drawings CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of my copending application Ser. No. 64,791, filed on Aug. 8, 1970 now abandoned.

BACKGROUND OF THE INVENTION This invention relates to blasting agents in the form of emulsions and, more particularly, to water-bearing blasting agents comprising an inorganic oxidizing salt, carbonaceous fuel, and a stearate salt emulsifying agent.

Ammonium nitrate-fuel oil compositions, often referred to as ANFO, are an inexpensive source of energy for blasting but have serious shortcomings. These compositions cannot be used in wet boreholes unless they are packaged in waterproof containers or further processed. Furthermore, and more importantly, the explosive action and density of ANFO explosives are not sufficiently high for many commercial uses. Thickened water-bearing blasting agents have been successful commercially because they can be used under a variety of conditions, e.g., in boreholes containing water, and they have good densities and detonation velocities. These products typically comprise an oxidizing component, e.g., ammonium nitrate, a fuel component dispersed or dissolved in an aqueous medium, which is thickened, usually by guar gum and, where premium performance is required, generally contain sensitizers. The incorporation of thickeners, such as guar gum, in the explosive composition increases the cost of the blasting agent and still inorganic nitrate salts are leached from these products when exposed to water. Emulsion type blasting agents have been known for some time. These blasting agents contain at least one inorganic oxidizing salt, water, carbonaceous fuel, sensitizer and an emulsifier to form a water and oil emulsion. Representative emulsion type blasting agents are disclosed in US. Pat. No. 3,447,978. Emulsion type blasting agents are relatively inexpensive, but they also have certain serious shortcomings that limit their commercial usefulness. These blasting agents have poor water resistance. When they are placed in a wet borehole they take up water present in boreholes thereby diluting the remaining components. Soluble materials such as nitrate salts are also leached from the composition. The effect of these changes in the product composition is that sensitivity and explosive strength of the blasting agent are substantially decreased and sometimes the blasting agent is rendered ineffective. Emulsion type blasting agents of the prior art are not readily pumpable because generally they are similar in consistency to thin Vaseline. Further, when emulsion type blasting agents are packaged in, for example, bags prior to use, it is difficult to remove all the blasting agent from the container since residual blasting agent sticks to its walls. Obviously this presents both a safety and economic problem since the blasting agent remaining in the container is economic waste and also a hazard until it is safely disposed of, such disposition entailing additional cost. Accordingly, there is a need in the explosives industry for a low-cost, high-velocity explosive composition that is safe to handle, has improved water resistance, is readily pumpable, and does not adhere to walls of containers from which it is to be removed.

SUMMARY OF THE INVENTION The present invention provides a novel explosive composition, e.g., a blasting agent in the form of an emulsion comprising inorganic oxidizing salt, water, water-insoluble carbonaceous fuel, and sensitizer, the improvement which comprises said composition containing an ammonium or alkali metal stearate salt to form the emulsion. The water-bearing inorganic oxidizing salt and carbonaceous fuel containing the stearate salt form a stable emulsion due to the presence of the salt. The stearate salt that causes the emulsion to be formed imparts to the composition properties and characteristics not possessed by other compositions, e.g., blasting agents containing an emulsifying agent. First, and quite surprisingly, the water resistance of compositions emulsified with the stearate salts is substantially higher than those emulsified with other emulsifying agents. Second, the stearate salt emulsified composition is readily pumpable, and, third, it does not adhere to walls of containers in which it canbe packaged prior to use.

The emulsifier used in the composition of the present invention is a stearate salt selected from the class of ammonium and alkali metal stearate. The amount of stearate salt used in the blasting agent can vary within a wide range. Sufficient stearate salt must be'present in the blasting agent to form the emulsion. At least about 0.5 percent by weight and generally not more than about 6 percent by weight stearate salt is added to the blasting agent. However, larger amounts can be used since excess quantities function as a fuel. The stearate salt used in the composition can be: formed by the reactin of stearic acid with an inorganic base. The stearate moiety is combined with an alkali. metal or ammonia, e.g., ammonium, sodium, potassium and lithium stearates. The preferred emulsifying agent that produces a blasting agent having optimum properties, e.g., water resistance and rheology, is sodium stearate. Preferably, stearic acid is added to the explosive composition in combination with the stearate salt. Especially in low shear mixers the addition of stearic acid to the composition lessens the time otherwise required for emulsification. The amount of stearic acid added to the composition can vary from 0.5-6 percent, by weight, and in most instances from about 1-4 percent by weight. The preferred composition contains about 2 percent by weight sodium stearate or about 1. percent by weight sodium stearate and 1 percent by weight stearic acid.

The explosive composition of this invention can be formed by mixing an aqueous solution of an inorganic oxidizing salt(-s) with carbonaceous fuel and stearate salt emulsifier, agitating the mixture until a thickened emulsion is formed and then incorporating gas, for example, by the addition of gas-carrying material, e.g., microballoons, in situ formation of gas bubbles, or injection of'air, and obtaining a blasting agent in emulsion form. Alternatively, if the sensitizer is a particulate material, e.g., aluminum or trinitrotoluene, it can be added before the emulsion forms.

PREFERRED EMBODIMENTS OF THE INVENTION The inorganic oxidizing salt used in the explosive composition of the present invention is usually present in amounts of about from 20-85 percent, preferably 45-75 percent, by weight of the total composition. Examples of inorganic oxidizing salts include ammonium, alkali metal and alkaline earth metal nitrates, and perchlorates as well as mixtures of two or more such salts. Representative inorganic oxidizing salts that can be used either alone or in combination include ammonium nitrate, ammonium perchlorate, sodium nitrate, sodium perchlorate, potassium nitrate, potassium perchlorate, magnesium nitrate, magnesium perchlorate and calcium nitrate. Preferably, the inorganic oxidizing salt present in the water phase in the emulsified explosive composition is ammonium nitrate alone or, most preferably, in combination with up to about 25 percent by weight sodium nitrate.

The amount of water added to the explosive composition is about from 5-30 percent by weight, and preferably, about from -25 percent by weight.

The essential feature of the present invention is the use of a stearate salt as emulsifying agent in the compositions described herein. It is surprising that the stearate salt forms a water-in-oil emulsion, i.e., an emulsion characterized at least by a continuous oil phase because the value of the hydrophilic-lipophilic balance (HLB) of stearate salts, e.g., sodium stearate, is about 18. Generally emulsifiers with HLB values of 11 to 20,

'and particularly those with HLB values closer to 20,

tend to form oil-in-water emulsions rather than waterin-oil emulsions which tend to be formed by emulsifiers with HLB'values of l to 9, and particularly those with HLB values closer to l.

ltzis most surprising that the emulsion formed when a stearate salt is used as the emulsifying agent should have such excellent water resistance. It is thought that the water resistance is due to two factors, one of which is the tight packing (as electron microscopy reveals) of the microscopically small particles of the emulsion and the other is the hydrophobic character of the stearate moiety.

The amount of stearate salt added to the mix can vary from about 0.5-6 percent by weight, and usually amounts of about from 1-4 percent are satisfactory to form a stable emulsion. As shown in the working examples hereinbelow, the emulsion blasting agents of the present invention do not lose their effectiveness when contacted with water often found in boreholes. On the other hand, emulsion type blasting agents not containing stearate salt in a water environment, such as a borehole containing water, become less sensitive to initiation and also lose some, if not all, their explosive strength and exhibit relatively low detonation velocities. Generally under such conditions explosive strength is lost due to the fact that the blasting agents pick up and retain water present in the borehole, which retained water dilutes the compositions and severely weakens their explosive capability. Not only are the stearate salt emulsions highly water-resistant, but are pumpable from a source of supply to a borehole or for packaging. Quite advantageously, the stearate emulsions made by the process of this invention do not adhere to the walls of the plastic containers in which they are packaged so there is no loss of explosive composition or disposal problem.

The carbonaceous fuel that is used to form the continuous oil phase is characterized as being insoluble in water and is a liquid or solid, or blends thereof, which are liquid at the time of emulsion manufacture. The

term oil means any hydrocarbon or substituted hydrocarbon that functions as a fuel in the explosive reaction. Carbonaceous fuels forming the oil phase can be present in the composition individually or in combination. Suitable carbonaceous compounds that function as fuels forming the oil phase of the emulsion are hydrocarbon oils such as diesel oil, paraffin wax, tall oil, long-chain fatty acids such as oleic acid, nitroalkanes such as nitropropane, aromatic hydrocarbons such as benzene, substituted aromatic hydrocarbons such as nitrobenzene, and the like. Preferably, fuel oil is used as the carbonaceous fuel. It is believed that the continuous phase of oil surrounds the supersaturated solution of the inorganic oxidizing salt, for example, ammonium nitrate, and retards crystal growth. Generally, the carbonaceous fuel forming the oil phase of the blasting agent is present in amounts sufficient to obtain an oxygen balance between about -30 to +10 percent, and preferably about-l 0 to 5 percent. Usually the carbonaceous fuel is present in amounts of about 2-12 percent and most often about 4-8 percent, based on the weight of the composition.

A sensitizer is added to the emulsion in order to assure consistent and reliable detonation or to render the composition cap-sensitive. Any of the well known sensitizers compatible with the emulsion system can be incorporated into the explosive composition. Representative sensitizers include particulate explosives such as trinitrotoluene, pentaerythritol tetranitrate, 2,4,6- trinito-N-methylaniline, cyclotrimethylenetrinitramine, cyclotetramethylenetetranitramine, nitrostarch, monomethylamine nitrate, ethylenediamine dinitrate, explosive-grade nitrocellulose and smokeless powder. Particulate metals such as certain forms of aluminum and magnesium, preferably having a particle size range from 30 to passing 325 mesh can also be used to increase the energy in the explosive composition and in some instances as sensitizers. Any suitable means for incorporating gas bubbles in the present blasting agent can be used. For example, gas bubbles can be incorporated by dispersing gas in the blasting agent by direct injection, such as by air or nitrogen injection, or the gas can be incorporated by mechanically agitating the composition and beating air therein. However, preferably, incorporation of gas is accomplished by the addition of particulate material such as aircarrying solid material, for example, phenolfurmaldehyde microballons, glass microballoons or silicious glass or the in situ generation of gas due to the decomposition of chemical compounds. The amount of gas bubbles incorporated in the blasting agent results in a composition containing about from 5-50 percent, and preferably 10 to 35 percent gas bubbles, by volume.

Alternatively, if desired, conventional fuels can be added to the composition as auxiliary fuels. Any conventional fuel that is stable can be used. Examples of auxiliary metallic fuels, which are especially preferred,

The following specific examples are given for a clearer understanding of the invention. Lead compression tests employed about 1% pounds of blasting agent. These examples are illustrative only and are not to be construed as limiting the underlying principles and scope of the invention.

EXAMPLE 1 7 Parts solid ammonium nitrate and parts sodium nitrate were added to 72 parts of 75 percent ammonium nitrate liquor. The mixture was heated to 160 F. to dissolve the solid ingredients. One part sodium stearate was added to 5 parts No. 2 fuel oil together with 0.2 part hydrazine monohydrate (85 percent) and mixed at a temperature of 160 F. The fuel oil containing stearate salt was then added to the ammonium nitrate solution, mixed, and cooled to 150 F., thereby forming a thickened emulsion. 1.0 Part hydrogen peroxide (3, percent) was mixed with the thickened emulsion when the temperature of the emulsion was about 150 F. and small gas bubbles that function as sensitizing sites formed throughout the blasting agent.

The resulting blasting agent had a specific gravity of 1.25. A sample (approximately 3 /2 lbs.) of the blasting agent detonated at 35 F. in a 2-inch diameter pipe and had a detonation velocity of 4,233 meters per second.

EXAMPLE 2 7 Parts solid ammonium nitrate and 15 parts sodium nitrate were added to 71 parts of 75 percent ammonium nitrate liquor. The mixture was heated to 160 F. to dissolve the solid ingredients. 1 part sodium stearate and one part stearic acid were added to 5 parts No. 2 fuel oil together with 0.2 part hydrazine monohydrate (85 percent), and mixed at a temperature of 160 F. The fuel containing stearic acid and stearate salt was then added to the ammonium nitrate solution, mixed, and cooled to 145 F., forming a thickened emulsion. 1 Part hydrogen peroxide (3 percent) was mixed with the thickened emulsion when the temperature of the emulsion was about 145 F. and small gas bubbles that function as sensitizing sites formed throughout the blasting agent.

The resultant thickened blasting agent had a specific gravity of about 1.2. A sample of the blasting agent (approximately 3% lbs.) was detonated at 35 F. in a 2- inch diameter pipe with a detonation velocity of about 4,000 meters per second.

EXAMPLE 3 For comparative purposes, 7 parts solid ammonium nitrate and 15 parts sodium nitrate was added to 71 parts of 75% ammonium nitrate liquor. Two parts of emulsifying agent EZ-rnul, which is the tall oil amide of tetraethylene pentamide' and 0.2 part hydrazine monohydrate (85 percent) was incorporated in 5 parts No. 2 fuel oil and heated to 160 F. The emulsion thickened and 1 part hydrogen peroxide (3 percent) was added as an aqueous solution to the thickened emulsion and mixed with it to form small bas bubbles in the emulsion that serve to sensitize the blasting agent.

Comparative Tests a. A 4 t 7-gram sample of the blasting agent prepared according to the procedure describedin Example 1 was shaped in the form' of a ball and placed in a l-liter beaher with 600 ml. of water. After 24 hours the blasting 6 agent was detonated at 45 F. and compressed a lead block 1% inches.

b. a 398-grarn sample of the blasting agent prepared according to the procedure described in Example 2 was shaped in the form of a ball and was placed in a l-liter beaker with 400 ml. of water that completely covered the blasting agent. After 7 days the water was poured off and the blasting agent weighed 399 grams. The water-exposed blasting agent was detonated, and compressed a lead block 1% inches.

c. a 363-gram sample of the blasting agent prepared according to the procedure described in Example 3 was shaped in the form of a ball and placed in a l-liter beaher with 600 ml. of water. After 24 hours the blasting agent weighed 560 grams due to water retention. The water-exposed blasting agent failed to detonate.

EXAMPLE 4 210 Parts of granular ammonium nitrate were added to 720 parts of a percent ammonium nitrate liquor and heated to 160 F. in order to dissolve solid ammonium nitrate. 20 Parts No. 2 fuel oil and 30 parts paraffin wax were mixed with 20 parts sodium stearate and heated to 160 F. to liquefy the paraffin. The fuel containing the emulsifier was added to the ammonium nitrate solution and cooled to 150 F. whereupon thickening commenced and 2 parts of N,N'-dinitrosopentamethylenetetramine (60 percent) were incorporated in the thickened emulsion and decomposed to form small gas bubbles throughout the resulting blasting agent.

The blasting agent was detonated at F., unconfined, to compress a lead block 2-13/16 inches and had a detonation velocity of 5,644 meters per second. A sample of this blasting agent was packaged in a polyethylene bag and stored for about one month. The blasting agent was removed from the bag, and it was observed that the blasting agent did not adhere to the walls of the bag and thus the bag was completely empty of said blasting agent.

EXAMPLE 5 14 Parts solid ammonium nitrate and 30 parts sodium nitrate were added to 144 parts ofa 75 percent ammonium nitrate liquor. The mixture was heated to 160 F. to dissolve the solid ingredients. 2 parts sodium stearate and 1 part stearic acid was added to 10 parts No. 2 fuel oil together with 1 part microballoons and mixed at a temperature of 160 F. The fuel oil containing stearate and microballoons was then added to the ammonium nitrate solution and mixed at F, forming a thickened emulsion.

The resulting blasting agent had a specific gravity of 1.33. A sample of the blasting agent at 75 F. compressed a lead block 2-5/16 inches and at 40 F. 1-13/16 inch.

EXAMPLE 6 The resulting blasting agent had a specific gravity of l 1.39. A sample of the blasting agent at 75 F. compressed a lead block 2-5/16 inches and at 40 F. 1-1l/l6 inch.

EXAMPLE 7 The procedure described above in Example was repeated except that one part granular aluminum was substituted for the microballoons.

The resulting blasting agent had a specific gravity of 1.35. A sample of the blasting agent at 75 F. compressed a lead block 2% inches and at 40 F. 11/16 inch.

EXAMPLE 8 5.5 Parts of solid ammonium nitrate and 15 parts sodium nitrate were added to 72 parts of a 75 percent ammonium nitrate liquor and heated to 160 F. in order to dissolve water-soluble solid ingredients. 5.5 Parts of corvus oil were mixed with 2 parts of sodium stearate and added to the ammonium nitrate solution. The mix was agitated to thoroughly-mix the ingredients, in the process of which it cooled to 147 F., and a thickened emulsion formed. 1 part glass microballoons was immediately added to the thickened emulsion and mixed therein to distribute the air-entrapping material throughout the emulsion.

The resulting blasting agent in a 5-inch diameter was detonated unconfined at 78 F. and had a detonation velocity of 5,422 meters/sec.

EXAMPLE 9 99 Parts ammonium nitrate and 46 parts sodium nitrate were mixed with 40 parts water at a temperature of 160 F. to dissolve solid ingredients. Two parts sodium stearate and two parts stearic acid was added to l 1 parts fuel oil and mixed at a temperature of 160 F. The fuel oil containing stearate was then added to the ammonium nitrate solution, mixed and cooled to 150 F. thereby forming a thickened emulsion. Upon thickening 'of the emulsion 1.4 parts N,N'-dinitrosopentamethylenetetramine (60 percent) were added when the temperature of the emulsion was about 150 F. and mixed therein at which time small gas bubbles that function as sensitizing sites formed throughout the blasting agent.

A sample of the blasting agent at 100 F. compressed a lead block 2% inches and at 74 F. 2% inches and at 40 F. 2% inches.

' A sample of this blasting agent was packed in a polyethylene plastic bag and stored for about a week. The blasting agent was removed from the container, and it was observed that it did not adhere to the walls of the container.

EXAMPLE 10 24 Parts solid ammonium nitrate and parts sodium nitrate were added to 54 parts of a 75 percent ammonium nitrate liquor. The mixture was heated to 170 F. to dissolve the solid ingredients. One part lithium stearate and 1 partstearic acid were added to a hot mixture (170 F.) of 2.5 parts of No. 2 fuel oil and 2.5 parts of paraffin wax. The fuel containing stearic acid and stearate salt was then added to the ammonium nitrate solution. The mix was agitated to thoroughly mix the ingredients and a thickened emulsion formed at 156 F. Upon thickening of the emulsion, 0.13 parts N,N'- dinitrosopentamethylenetetramine (60 percent) were added and mixed therein at which time small gas bubbles that function as sensitizing sites formed throughout the blasting agent.

A sample of this blasting agent 6 months old compressed a lead b 1ock 2-1 1 16 incl s at 40 F.

EXAMPLE 1 1 thylenetetramine (60 percent) were added and mixed therein at which time small gas bubbles that function as sensitizing sites formed throughout the blasting agent.

A sample of the blasting agent compressed a lead block 2-13/16 at 46 F.

I claim:

1. In an emulsified explosive composition comprising inorganic oxidizing salt, water, water-insoluble carbonaceous fuel and sensitizer,'the improvement'which comprises said blasting agent containing a stearate salt selected from the class consisting of ammonium and alkali metal stearates to form the emulsion.

2. A product of claim 1 containing stearic acid.

3. A product of claim 1 wherein the stearate salt is sodium stearate.

4. A product of claim 3 containing stearic acid.

5. A product of claim 3 containing about from 0.5-6 percent by weight stearate salt.

6. A product of claim 3 containing about from l-4 percent by weight stearate salt.

7. A product of claim 3 containing occluded gas as a sensitizer.

8 A product of claim 3 containing particulate alluminum as a sensitizer.

9. A product of claim 3 containing gas-entrapping material as a sensitizer.

10. A product of claim 3 containing gas bubbles as a sensitizer.

11. A product of claim 3 containing hydrocarbon fuel.

12. A product of claim 11 wherein the hydrocarbon is fuel oil.

13. A product of claim 3 containing ammonium nitrate.

14. A product of claim 13 containing sodium nitrate.

15. In an emulsified blasting agent comprising, by weight, about 20-85 percent ammonium nitrate, about 5-30 percent water, sufficient hydrocarbon fuel to obtain an oxygen balance in the blasting agent about from -10 to +5 percent, and about 5-40 percent, by volume, occluded gas as sensitizer, the improvement which comprises said blasting agent composition containing about 0.5-6 percent by weight sodium stearate to form the emulsion.

16. A product of claim 15 containing stearic acid.

17. A product of claim 16 containing about 0.5-6 percent by weight stearic acid.

18. A product of claim 15 containing about l-4 percent by weight sodium stearate and about 1-4 percent by weight stearic acid.

19. A product of claim 15 wherein the occluded gas is gas bubbles.

9 10 20. A product of claim wherein the occluded gas 23. A product of claim 21 containing up to about 25 is in the form of air-carrying solid material. percent by weight sodium nitrate.

21. A product of claim 15 containing, by weight, 24. A product of claim 21 wherein the fuel is fuel oil. about 4575 percent ammonium nitrate, about 10-25 25. The product of claim 18 wherein the sodium steapercent water, about 4-8 percent hydrocarbon fuel. 5 rate and stearic acid are present in substantially equal 22. A product of claim 21 containing l-4 percent amounts. stearic acid.

PEI-1050 /69) UNI s'ms PA GER IHCAT $770522 Dated Nov. 6, 1973 Inventofls) Ernsfi Aa Tomic It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as ohown below:

Column 8, lines 38-39, "allulminuun should read --a.1uminum--; line 55, "5- LQpercent should read --=5-=5O percent".

Signed and sealed this 9th day of April 197A;

(SEAL) Attest:

EDWARD M .FLET CHER JR 0 Attesting Officer Cw MARSHALL DANN Commissioner of Patents mg UNITED STATES PATENT OFFICE CERTIFICATE OF CURRECTION Patent No. 3,770,522 Dated NOV. 6, 1973 Inventofla) Ernsb 1Lv Tomic It is certified that error appears in the above-identified patent and ghat said Letters Patent are hereby eorrecmd as ahow'n below:

Column 8, lines 38-39, alluminum' should read --a.1uminum--; line 55, "5- l-O"percent" should read -=-5--5O percent".

Signed and sealed this 9th day of April 197M.-

(SEAL) Attest:

EDWARD 'I' I.FLETCHE H,JR. I 0. MARSHALL DANN Attesting Officer Commissionerof Patents

Claims

2. A product of claim 1 containing stearic acid.
3. A product of claim 1 wherein the stearate salt is sodium stearate.
4. A product of claim 3 containing stearic acid.
5. A product of claim 3 containing about from 0.5-6 percent by weight stearate salt.
6. A product of claim 3 containing about from 1-4 percent by weight stearate salt.
7. A product of claim 3 containing occluded gas as a sensitizer. 8 A product of claim 3 containing particulate alluminum as a sensitizer.
9. A product of claim 3 containing gas-entrapping material as a sensitizer.
10. A product of claim 3 containing gas bubbles as a sensitizer.
11. A product of claim 3 containing hydrocarbon fuel.
12. A product of claim 11 wherein the hydrocarbon is fuel oil.
13. A product of claim 3 containing ammonium nitrate.
14. A product of claim 13 containing sodium nitrate.
15. In an emulsified blasting agent comprising, by weight, about 20-85 percent ammonium nitrate, about 5-30 percent water, sufficient hydrocarbon fuel to obtain an oxygen balance in the blasting agent about from -10 to +5 percent, and about 5-40 percent, by volume, occluded gas as sensitizer, the improvement which comprises said blasting agent composition containing about 0.5-6 percent by weight sodium stearate to form the emulsion.
16. A product of claim 15 containing stearic acid.
17. A product of claim 16 containing about 0.5-6 percent by weight stearic acid.
18. A product of claim 15 containing about 1-4 percent by weight sodium stearate and about 1-4 percent by weight stearic acid.
19. A product of claim 15 wherein the occluded gas is gas bubbles.
20. A product of claim 15 wherein the occluded gas is in the form of air-carrying solid material.
21. A product of claim 15 containing, by weight, about 45-75 percent ammonium nitrate, about 10-25 percent water, about 4-8 percent hydrocarbon fuel.
22. A product of claim 21 containing 1-4 percent stearic acid.
23. A product of claim 21 containing up to about 25 percent by weight sodium nitrate.
24. A product of claim 21 wherein the fuel is fuel oil.
25. The product of claim 18 wherein the sodium stearate and stearic acid are present in substantially equal amounts.