DE2219249A1 - Explosive mixtures with a content of calcium nitrate - Google Patents

Description

Dr. Karl Th. Hegel

Tx . -ι -r T7--1 -r ^ . -ι ι 2OOO Hamburg 5O

Dipl.-Ing.KlausDlckel _n «« «^

- ^ ° Great Mountain Road 223

Patent attorneys P.O. Box 500662

Telephone (04U) 396205 Post bank account: Hamburg 291220

ρ * -] Bank: Dresdner Bank AG., 3813897

Telegram address: DoeUnerpatent

221924 *

Portfolio: H 1939

Dr. He / Mü

IEECO CHEMICALS
726 .Kennecott Building Salt Lake City, Utah, V.St.A.

Explosive mixtures with a content of calcium nitrate

The present invention "relates to improved explosive mixtures, which contain calcium nitrate. Generally speaking, the invention relates to explosives comprising a fuel in In the form of a liquid hydrocarbon in emulsified form and calcium nitrate.

Fuel-sensitized ammonium nitrate explosives have proven to be important factors in the field of technically successful explosives. Explosive mixtures made from ammonium nitrate masses, the oxygen content of which is in equilibrium with a fuel oil, are not suitable as such for use in water-containing boreholes, although they are widely used and may be suitable for some applications. Aqueous, sludge-like disintegrants, for example so-called WCN sludge masses crosslinked with aluminum, which form a stable, sludge-like mixture of solid ammonium nitrate particles and a serinibilizing agent made of aluminum metal in a water-soluble! ^{! i} en i - mmonnibratlösung contain (see for example the

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SAD

American reissue patent 25,695), are very successful has been used technically even in water-bearing boreholes. In this so-called NCN sludge there are also both solid ones such as liquid hydrocarbon fuels, e.g. fuel oil, have been incorporated with success, the liquid Fuel oil was dispersed therein using common emulsifying agents.

In previous technical attempts to create more economical Mixtures of explosives without metallic sensitizers, such as aluminum, or highly explosive sensitizers, such as trinitrotoluene, which has a particle size of more than 30 Tyler mesh (0.59 mm), are mixtures has been proposed in various forms, including aqueous sludge-like masses consisting essentially of ammonium nitrate or Passed ammonium nitrate and sodium nitrate as well as fuel oil and water. But these latter masses detonated in the dry or water-containing boreholes not satisfactory except when using multiple additional charges and a high mixing ratio from booster charge to mud explosive of, for example, 1:25 or more.

In American patents 3,083,127, 3,147,163 and For example, 3,236,180 has been described as calcium nitrate is essentially equivalent to ammonium nitrate and / or sodium nitrate or as a partial substitute for its use Serve as an inorganic oxidizer in various types of explosive mixtures, including those mixtures which contain liquid hydrocarbon fuels. The use of 2 or more inorganic oxidizing agents, one of which can be calcium nitrate, is already standard

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de the technology described (see American patents 3 201 291 and 3 249 476) as a means of reduction the solidification point or the crystallization temperature, so a higher salt concentration in the water-containing Enable explosives. The use of calcium nitrate as a possible component of explosives is also in others References including U.S. Patents 3,390,029, 3,450,582, 3,459,608, 3,475,238, and 3,496,040. Both ammonium nitrate and sodium nitrate have technical Widely used, but calcium nitrate has apparently not been found to any significant extent in explosive mixtures in technical use. Calcium nitrate is generally considered to be less effective than an oxidizer for explosives Ammonium nitrate, although calcium is divalent and therefore contains two nitrate groups for one calcium atom Ammonium nitrate only binds a nitrate group to the ammonium ion. In addition, technical grade calcium nitrate is usually hydrogenated. For example, it contains 4 molecules of water. This further reduces its oxidizing effect. Thus the The prior art does not suggest any further improvements in explosive masses through the use of calcium nitrate can be achieved.

However, it has been found that the addition of calcium nitrate increases mud-shaped explosives, which are solid particles of ammonium nitrate or mixtures of ammonium nitrate and sodium nitrate contained in a thickened or gelled solution of Ammonium nitrate are dispersed, the solution also still being an alkylene glycol of low molecular weight, for example Ethylene glycol, increases the effectiveness of such masses. The use of calcium nitrate allows the application to

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smaller amounts of an aqueous solvent to obtain a pourable and pumpable, albeit viscous, slurry. You diminished continues the freezing point, i.e. the gelation temperature, and thereby avoids unnecessary heating of the Solution to get the desired concentration of oxidizing salts and it will eventually accelerate setting or solidifying the sludge after it is put in place or inserted into the blast hole. This is a Separation and settling of suspended particles in the sludge prevents the water resistance and sensitivity of the Mass is improved by preventing migration of gas bubbles originally trapped or otherwise incorporated into the mixture or escape are secured. The compositions described here preferably contain solid, finely divided fuels or sensitizers such as aluminum, gilsonite asphalt, sulfur, Trinitrotoluene and the like.

It was also found that the calcium nitrate according to the present Invention can be used to create a fuel-sensitized explosive mass based on To produce ammonium nitrate, which has unique and valuable characteristics. The hydrous explosives, like sludge-shaped explosives that are of technical importance have used solid fuels, such as aluminum, trinitrotoluene, sulfur, smokeless powder, solid hydrocarbons and other agents co-dispersed with the solid oxidizing agents in a continuous liquid phase, which in turn generally consisted of a thickened or gelled solution of an oxidizing agent. Although .savings through the use of less expensive fuels, such as liquid petroleum fractions - for example fuel oils -

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can be achieved is the production of stable dispersions of the fuel oil in a water-containing phase of the fuel mixture difficult. According to the invention it has been found that calcium nitrate as a result of its inherent endeavor to produce an emulsion-like mixture of finely divided liquid hydrocarbon oil particles, in suitable proportions in .einem ammonium nitrate containing, with a liquid Hydrocarbon fuel sensitized explosive can be used in the fuel and the solid part of ammonium nitrate with or without other oxidizing agents such as Sodium nitrate is uniformly dispersed in the continuous aqueous liquid phase, which generally consists of a thickened or gelled solution of an oxidizing agent. Such masses are extraordinarily sensitive to detonation; they can even at relatively low rates Temperatures, e.g. 5 ° C and lower, are detonated.

The endeavor of the calcium nitrate, an emulsion-like dispersion Forming a liquid hydrocarbon fuel is not readily explicable. The calcium nitrate can, however not regarded as a common emulsifier in dispersing the liquid hydrocarbon fuel Emulsifiers or emulsifiers are usually used in very small amounts and are surface active agents, which enable the formation of stable, non-uniting emulsions of liquid particles in a different liquid phase. The calcium nitrate used according to the present invention differs from these conventional emulsifiers in that that calcium nitrate in larger quantities of 5% or more, calculated on the total weight of the mass, must be used,

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before it forms an emulsion-like dispersion, and that the Calcium nitrate itself does not form a stable emulsion, but that following the emulsion-like dispersion with the aid calcium nitrate a "thickener must be used, to prevent aggregation and subsequent loss of the emulsion-like form, and finally the calcium nitrate not only acts in such a way that it is emulsion-like Forms dispersion, but that it also serves as an oxidizing agent or an effective component of the explosive, a success that is not achieved with the usual emulsifiers.

In the following description, all the itoζent information relate or parts by weight to percentage weights and parts by weight, calculated on the total weight of the mass, unless expressly stated is stated otherwise.

Essential components

The essential components of the explosives mixtures according to of the invention are calcium nitrate, a liquid hydrocarbon explosive, an inorganic oxidizing salt, the is not the same as calcium nitrate, for example ammonium nitrate with or without further oxidizing agents ", and enough water to produce a to deliver a pumpable mixture, the water either coming from the hydrated calcium or added water or both, and finally a suitable thickening agent.

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The calcium nitrate used in the present invention is effective primarily as an oxidizing agent and as a substance promoting emulsification. It also creates a means of... Around the whole Reduce water content by forming a beneficial eutectic solution if it is within this with certain combined with other salts, the preferred calcium nitrate for the intended use is the one commercially available, Calcium nitrate used for fertilization purposes. A typical analysis of the commercially available calcium nitrate is shown in US Pat Table I below.

Table I Typical analysis of a calcium nitrate for fertilization purposes

Component weight percent e

0a (N0,) _o (anhydrous) 80.4 to 81.4%

Water (hydrated water) 13 to 14 %

NH ₄ NO ₅ 4.8 to 5.4% 'Mg (NO ₇ J ₂ 0.5 to 1.0%

Particle size
(Stitches according to Tyler)

Nr * 10 (2.00 mm) left 4.5 %

No. 20 (0.84 mm) ö "78.0 %

No. 40 (0.42mm) "" 97.0 %

No. 60 (0.25mm) "" 99.7 %

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Although the calcium nitrate described above is used for fertilization purposes A hydrated and granular product whose particle size distribution is given above can do that Calcium nitrate can also be ground or otherwise treated to give various physical forms and / or particle size distributions to have. In addition, anhydrous calcium nitrate or calcium nitrate with a different hydrate content can also be used will. If calcium nitrate with a different water content is used, a small amount of additional water is added to the Difference from that present in calcium nitrate as water of crystallization used, as described in more detail below will. The amount of water is directly related to the hydration state of the calcium nitrate used and the Total amount of water required to obtain a pumpable product in the course of the production of the mass, immediately proportional. The calcium nitrate is generally dissolved or brought into solution during the manufacture of the explosives. Meanwhile is under the working conditions, i.e. those of the time of use, the temperature, the pressure and other conditions of use, the explosion mixture, part of the calcium nitrate, which is from a small amount to im substantial to the total, in solid, hydrated form.

In the explosive mixtures according to the invention, the liquid Hydrocarbon fuel is the primary fuel. It is present as a uniform and homogeneous dispersion of separate liquid droplets. Under working conditions the dispersed liquid particles are about 0.01 mm or less in diameter. As a result of the combined Effect of calcium nitrate and the thickener

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these do not settle quickly or combine in the medium in which particles are suspended. Preferably wise the dispersed liquid hydrocarbon fuel particles have a colloidal size, so they are between 5 to about £ 5000. -

The hydrocarbon fuels can be aliphatic, alicyclic or aromatic in nature. Suitable fuels can be either saturated or unsaturated. For example Benzene, toluene and xylenes can be used. Preferred fuels include mixtures of normally liquid hydrocarbons, commonly called petroleum distillates such as gasoline, petroleum and diesel oil. A particularly preferred liquid fuel is fuel oil IMr. 2.

In the course of the production of the explosive mixtures according to the invention, one or more customary thickeners are used used to regulate the viscosity of the mass and thus enable it to be pumped, while at the same time the finely divided sensitizing gas bubbles are held in place and also a somewhat substantial settling and / or preventing the additives from combining. The thickeners also improve water resistance the crowd. To the usual thickeners, as used in the art Known to include guaran gum and starch, as well synthetic polymeric products such as anionic heteropolysaccharide polymers, those under the trademark "Biopolymer XB-23" known can be used. Your solution depends on the flow properties of the mass.

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- ίο -

Besides the calcium nitrate in water, the liquid hydrocarbon fuel and a suitable thickening agent contains the explosives mixture according to the invention at least an inorganic oxidizing salt that is not identical to calcium nitrate. Such inorganic oxidizing salts are well known in the art and include inorganic nitrates such as ammonium nitrate and sodium nitrate, as well as inorganic ones Chlorates and perchlorates such as sodium perchlorate. That according to Ammonium nitrate used in the present invention may be one suitable for fertilization and / or one for explosives be. Both forms, granulated and melted, are suitable. In the manufacture of the mass according to the invention The inorganic oxidation salt can be used in solution or as a solid component. In a preferred embodiment, part of the salt used consists of ammonium nitrate in aqueous solution, and another part of the salt is called solid ammonium nitrate used.

The ratio of the amounts of the ingredients used in the explosives mixture according to the invention naturally depends on various factors, such as the desired explosive effect, the sensitivity and the like. Experts are undoubtedly able to achieve the desired optimal effects through routine experiments. In general, detonable mixtures have been used in which the amount of the organic oxidizing salt, other than calcium nitrate, is on the order of 25 to 75%, preferably about 60 to 70 % by weight. The amount of calcium nitrate used should be at least sufficient to effect a dispersion of the liquid hydrocarbon fuel in the mass during its manufacture. Satisfying crowds became

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"where the calcium nitrate content was as low as about 5% and as high as about 60 % . Preferred compositions usually contain from about 15" to about 30 % calcium nitrate.

The amount of liquid hydrocarbon fuel dispersed in a particular mass according to the invention should generally be determined by considerations of the oxygen balance so that the oxygen content of the explosive mixture is within a range of + 10% to about -20 % of the oxygen required is to precisely balance the mass. Preferred mixtures contain from about 6 to about 12 ° / o liquid hydrocarbon emulsion-type form.

Although the compositions according to the invention can be prepared without additional water (namely water which can be used in addition to the water of crystallization of the calcium nitrate) _; is generally a lot of. 1 to about 6%, additional water used to 10% ₉ preferably 3 during manufacture. In general, from about 0.05 to about 0.50%, preferably about 0.1%, of a conventional thickening agent is also used.

Preferred ingredients

In addition to the essential ingredients, the explosive mixtures according to the invention generally contain as preferred constituents in the production of the mass a density-reducing or gas-forming agent such as sodium nitrite, furthermore a crosslinking agent to effect gelatinization of the crosslinkable thickener used, and a means that the freezing point or the crystallization

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temperature, like sodium nitrate.

It is well known in the art to use gasbild & ade agents such as sodium nitrite and hydrogen peroxide to reduce the density and thereby in part to control the sensitivity of the sludge-like explosives mixture. The compositions according to the invention preferably use a small amount, for example about 0.01 to about 0.2 % or more, preferably about 0.05 %, of such a gas-generating agent in order to achieve a density of about 1.0 g / cm under the working conditions to obtain about 1.3 g / cm.

Crosslinking agents are also preferably used in conjunction with suitable crosslinkable thickeners when it is desired to gelatinize the mass during manufacture in order to stabilize the fine dispersion or distribution of the emulsion-like particles of liquid hydrocarbon fuel and to prevent undesired escape of the gas bubbles and in this way to preserve the detonation sensitivity resulting from the fine dispersion. Crosslinking agents are particularly valuable when the consistency or integrity of the composition is to be maintained in the presence of hydrous boreholes. For example, when guaran gum is used, the calcium resulting from the solution of calcium nitrate acts in part as a crosslinking agent. In addition, it has been found that an excellent crosslinking agent for guar gum can be obtained by using small amounts, for example about 0.05 to about 0.2 %, of an aqueous solution of ferric nitrate and sodium dichromate. Other cross-linking systems will be apparent to those skilled in the art.

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Other desirable ingredients

According to the prior art (see, for example, American Patent 3,249 4-7-6) it is known that sodium nitrate is beneficial as an inorganic oxidation salt component which lowers the crystallization temperature or the solidification point of the masses containing ammonium nitrate. In the case of the compositions according to the invention, it is desirable to regulate the freezing point, and the use of sodium nitrate as a component of the organic salt solution permits a certain amount of control of the freezing point. In one embodiment of the invention, the composition contains about 3 to about 5 % sodium nitrate.

Optional components

Various optional ingredients can also be included in the masses be incorporated according to the invention. For example, solid fuels such as finely divided aluminum, Magnesium alloys, usually solid hydrocarbons and the like, are added to the masses for strength to increase the mixes. Thiourea can also be used in very small amounts Quantities, for example about 0.05%> are used to regulate the rate at which the gas generating Sodium nitrite works. Furthermore, ethylene glycol, formamide and other mutually dispersible additives can be used in small amounts Quantities are added that do not change the essential character of the basic mixture.

Manufacture of calcium nitrate containing Explosives

The explosives mixes according to the present invention are preferably produced in such a way that a liquid

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Sigen hydrocarbon fuel in emulsion-like form in an aqueous solution of an oxidation salt, for example ammonium nitrate and / or ammonium nitrate and sodium nitrate, finely dispersed or distributed, with calcium nitrate also being added. Then the thickener is added. The resulting effectively stable dispersion is either pumped into suitable containers to serve as a packaged explosive, or it is mixed and pumping in a simultaneous mixing and pumping process using pumped trucks similar to those described in U.S. Patent 3,303 738 are used directly to load boreholes. In a typical manufacturing process, an oxidizing salt solution which has a freezing point of about 50 ° C. is prepared in such a way that about 3% sodium nitrate, 30% calcium nitrate for fertilization purposes, the typical analysis of which is given in Table I, 30% ammonium nitrate and 3 % additional water mixes together. The solution is used at about 60 ^° C. or about 10% above its freezing point. The preparation of the solution can be facilitated if the sodium nitrate is first dissolved in the additional water, followed by the addition of part of the ammonium nitrate and then an addition of the calcium nitrate and the remaining ammonium nitrate. Small amounts of a conventional thickener, for example 0.1 to 0.2%, are then added. The resulting oxidation salt solution is then combined with a liquid hydrocarbon fuel in emulsion-like form, for example with 7% of a fuel oil No. 2, by injecting small particles or droplets of the fuel oil through one or more spray nozzles into a moving stream of the solution to obtain an essentially homogeneous and fine dispersion.

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One or more of the above-described, preferred, desired or optional additives, such as, for example, crosslinking agents, are added to the stable dispersion thus obtained and / or additional amounts of solid ammonium nitrate and finely divided aluminum with or without a common gas generating agent. Usual equipment such as mixing funnels, Pumps, solids evacuators, and the like can be used provided the resulting mixture consists essentially of a mainly homogeneous fine dispersion that penetrates to the desired density Stirring in air is enriched with gas or, for example, by incorporating a gas-forming agent.

If the above-mentioned production method is used, the resulting stable emulsion of normally liquid hydrocarbon fuel droplets, which are intimately and homogeneously combined with the oxidizing constituents and other additives, can be immediately fired when it is directly introduced into a BoMoch. If gas-generating agents are used, the mass can be shot down after about 10 minutes. As the mass gradually cools down, the soluble oxidation salts begin to crystallize out of the solution. Ή ah about 10 to 14 hours, according to the existing ge amounts, the heat transfer conditions and the like, the composition is fixed, but remains smooth. After about 24 hours, the mass hardens under normal conditions and essentially separates the free water, as opposed to any bound water, which can be present as water of crystallization, water of hydration and the like. During the entire cooling period, the droplets of liquid carbon remain

sto £ f
water fuel uniformly dispersed and homogeneously in

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distributed within the mass in a free state. If you move your finger on a cross-section of a fully hardened mass according to of the invention rubs, small amounts of a liquid hydrocarbon fuel escape and "stick to the finger.

The effect of the mass according to the invention is generally not achieved by changing the state of the mass during cooling impaired. However, the mass is more sensitive as long as higher temperatures occur during the cooling process.

Although the method described represents a preferred embodiment, other technical compositions can also be used achieve the objects according to the invention as will be apparent to those skilled in the art. As a result, the invention is only through the following claims with regard to handling are limited.

The invention can be better understood with reference to the following illustrated examples.

example 1

According to this example, compositions according to the present invention which have the ingredients and characteristics given in Table II have, produced and successfully detonated as indicated in the table.

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Table II

Mass ' ABC _-

Components in% by weight solution, containing ammonium nitrate Calcium nitrate (according to table I) sodium nitrate water

1)

Thickener thiourea fuel oil No. 2

Dry, solid ammonium nitrate

Gas-forming agent ² ^ Cross-linking agent

Properties solution temperature fuel oil temperature density (g / cm) when n \ loading of the ^borehole}

Condition (12 hours after filling the borehole

Shooting results (in cardboard tubes, the length of which was several times the diameter, using a cast auxiliary charge 7.6 cm in diameter and 5.1 cm in length ¹ ^ - 20 C and 7 * 6 cm in diameter

5 ⁰ C "10.2 cm

12.7 cm "

29.4 55.5 55.5 25.5 28.4 28.4 5.5 4.3 4.5 5.5 5.5 5.5 0.12 0.14 0.14 0.06 0.07 0.07 7.0 7.5 7.5 55.0 20.0 20.0 0.2 0.2 0.2 0.2 0.1 0.05 70 ⁰ C 70 ⁰ C 70 ⁰ C 10 ° C 10 ⁰ C 10 ⁰ C 1.20 1.19 1.19 hard hard hard fixed fixed fixed

E ¹ D. D. F. F. j? D. D. D.

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1) - thickener = 4 parts of a so-called Stein-Hall "J-100" Guaran gums and 1 part of a product from Irma General-Mills under the trademark "XB-23", a commercially available one anionic heteropolysaccharide, produced by fermentation of a carbohydrate with the help of a Xanthomonas bacteria containing mass

2) - Gas-generating agent = 1 part sodium nitrite and 4 parts water

3) - Cross-linking agent = 1 part Na ₂ Cr ₂ O ₁ -, - 2H0 and

1 part water and 1 part -) = density at atmospheric pressure F = failure
D = detonated

The results in Table II show that the compositions according to the invention worked successfully at temperatures down to 5 ° C detonated when detonated in an open charge with a diameter of 12.7 cm.

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Example 2

According to this example, a liquid hydrocarbon fuel other than fuel oil Kr ₀ 2 is used to produce masses according to the invention and to ignite them with success. The compositions and results are shown in Table III.

Example 5

According to this example, aluminum metal is added as an additional or secondary fuel to a mass according to the invention. The resulting mass was successfully detonated as shown in Table IV.

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CD CO OO

Dimensions

in! atrium nitrate water calcium nitrate (see Table I) Ammonium nitrate thiourea * thickener

Ethylene glycol dry ammonium nitrate gas-forming agent ** cross-linking agent ^λ; ** fuel oil ür.

Fuel oil jtfr, Toluene benzene xylene

Density at 20 ⁰ C (g / cm ⁵ )

Shooting results (using an auxiliary charge of 7.6 cm in diameter and 5.1 cm in length

at 20 C and 7.6 cm diameter 10.2 cm

at 5 ° C and 7.6 cm in diameter 10.2 cm by 12.7 cm "15.2 cm"

Tabel III i. G H D. E. 4.2 ■ 4.2 4.2 4.2 4.2 2.8 2.8 2.8 2.8 2.8 30.8 30.8 30.8 30.8 30.8 32.2 32.2 32.2 32.2 32.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.2 0.2 0.2 0.2 0.2 22.0 22.0 22.0 22.0 22.0 0.4 0.4 0.4 0.004 0.4 0.3 0.3 0.3 0.3 0.3 7.8 2.6 - - - 5.2 7.8 - - - 7.8 - - - - 7.8 - - 1.15 1.17 1.18 1.17 1.12

failed failed failed failed failed detonated detonated detonated detonated detonated

failed detonated failed detonated

fails detonated

failed, detonated

fails detonated

- Guaran gum with the designation J-100 from Stein Hall

- Gas-generating agent as in Example 1

- Crosslinking agent: 9 parts of dimethylformamide to 1 part of titanium chloride

- density at atmospheric pressure

Table IV Dimensions Weight sprο ζ ent Sodium nitrate 5.6 water 2.4 Calcium nitrate (see Table I) 25.8 Ammonium nitrate 29.7 Thiourea 0.12 ' Thickener * 0.12 Ethylene glycol 0.24 Dry ammonium nitrate 25.3 Gas-generating agent ** 0.05 Cross-linking agent *** '0.5 Fuel oil No. 2 -4.4 Aluminum metal (with the designation LSA-123,
it is an overdone,
f-a crushed aluminum) 10.0 Density at 20 ⁰ O (g / cm ^) **** 1.20 ■

Shooting results (with a cast auxiliary charge 7.6 cm in diameter and 5.1 cm length)

at 5 G and 7.6 cm in diameter

10.2 cm "
at O ⁰ O and 15-2 cm in diameter

failed detonated detonated

see Table III see Table III see Table III see Table III

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Characteristics and use of explosives containing calcium nitrate

In general, find the explosives mixtures according to the invention "Particularly used as a blasting agent in boreholes with a diameter that is usually used in blasting operations in open pits and the like. In such applications it is generally desirable to have an effectively stabilized Prepare slurry of the feedstock either at the wellbore site or at a location remote from the wellbore and pumping the resulting mixture through a hose into the borehole.

During manufacture and at least during insertion into the borehole, the mixtures according to the invention are generally in the form of a pumpable, effectively stabilized Mud held, the consistency of which naturally depends on the temperature of the mass, the particular components and their quantities may fluctuate.

In well blasting operations, it is common practice to leave a period of time between the introduction of the explosive mixture in the borehole and the detonation to be measured shortly after minutes or long after several days can. During this period of time the explosives mixture is defeated often leaching by the water present in the borehole and settling under the action of gravity.

The explosive mixtures according to the invention can, if desired immediately after being introduced into the borehole, i.e. detonated. However, they stay

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also stable and can therefore detonate even in the gut when in the borehole. Water is available and / or if they have remained in the borehole for several days. This desired stability of the explosives mixtures is in the main part according to the invention the result of their relatively non-liquid nature, which the masses within of minutes after being placed in the wellbore. Within 24 "hours of placing in the In the borehole, the masses generally take on a hard, solid texture. As a result of these properties "remain the masses before the detonation always in the state of an essentially homogeneous dispersion with very good sensitivity.

Apart from the fact that the masses with the usual explosive measures can be used in larger quantities, these charges can also be packed in suitable containers, for example in plastic bags or in cardboard tubes, and detonate in this form at the site of the explosion.

The critical diameter of the masses according to the invention can be controlled within a practical range such that the masses can be safely pumped through a hose of subcritical diameter. For example, you can have one Mass, the critical diameter of which is 12.7 cm, into one Drill hole 15 »2 cm in diameter or more using a Pump in a hose that is approximately 10.2 cm in diameter. ■

The explosive mixtures according to the invention are preferably enriched with gas by the incorporation of small gas bubbles up to a density which is less than d. ± e theoretical

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2219/49

Maximum density in order to increase the sensitivity of the mass
raise. Such fumigation measures are well known in the art. Such methods can be used to achieve a density of about 1.0 g / cm or less to about m "^, preferably of 1.2 g / cm, under the working conditions, regardless of the condition of the mass.

Although the present invention has been described with reference to certain illustrative examples and preferred embodiments is, various possible changes are obvious to those skilled in the art. Such changes should be made within are within the scope of the invention as characterized by the following claims.

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Claims (1)

Patent claims Explosives enriched with gas to a certain density mixture, characterized by a homogeneous dispersion of a) at least one inorganic nitrate oxidizing agent which is not identical to calcium nitrate, b) a liquid hydrocarbon in emulsion-like _ Form as the main fuel, c) calcium nitrate in an amount that is at least sufficient, around. to prevent substantial confluence of the hydrocarbon, ■ d) water in an amount sufficient to produce an effectively stable sludge of the mass under the conditions of To achieve manufacturing and pumping, and e) a thickener, the composition being further characterized in that it is substantially resistant to sedimentation of the constituents Action of gravity and degassing is stable. 2. Composition according to claim 1, characterized in that the inorganic The nitrate oxidizer is ammonium nitrate. -). Composition according to Claim 1, characterized in that the inorganic nitrate oxidizing agent consists of ammonium nitrate and sodium nitrate. 20985 1/0657 4. Composition according to claim 1, characterized in that the liquid hydrocarbon fuel consists of an aromatic
Hydrocarbon. 5. Composition according to claim 1, characterized in that the liquid Hydrocarbon fuel is a petroleum distillate. 6. Composition according to claim 1, characterized in that the liquid Hydrocarbon fuel is composed of No. 2 fuel oil. 7. Composition according to claim 1, characterized in that it contains a minor proportion of a crosslinkable thickener
having. 8. Composition according to claim 7 »characterized in that it has a has a smaller proportion of a crosslinking agent. 9. Composition according to claim 8, characterized in that the crosslinking agent consists of approximately equal parts of water, sodium dichromate and ferric nitrate. 10. Composition according to claim 1, characterized in that it is replaced by smaller amounts of sodium nitrate as a gas-forming agent
is enriched with gas bubbles. 11. Composition according to claim 1, characterized in that it has a smaller proportion of cross-linkable guar gum 12. The composition of claim 1, characterized in that it contains about 5 to about 60% solid hydrated calcium nitrate. 209851/065 7 13. An explosives mixture with a substantially balanced oxygen balance, which has a density of about 1.0 g / cm to about 1.3 g / cm, characterized in that it consists essentially of about 20 to 30 % calcium nitrate, furthermore of at least about 3% total water, further from about 60 to about 70% ammonium nitrate, further from about 3 to about 5 ° / ° of sodium nitrate, further from about 6 to about 12% of a normally liquid hydrocarbon fuel in emulsion-like shape and at least about 0.1 % of a cross-linkable guar gum as thickener 14. Mass according to claim 13, characterized in that it has a firm, cast-like consistency at the time of use. 15 · Composition according to claim 13 »characterized in that it has a plastic consistency at the moment of use
having. 16. Composition according to claim 13, characterized in that it at the moment it is poured into a container or into the point of use, a pourable, liquid-like Has consistency. - 209851/065 7 -. <'