US3783053A - Process for manufacturing gasentrained aqueous gel explosive - Google Patents
Process for manufacturing gasentrained aqueous gel explosive Download PDFInfo
- Publication number
- US3783053A US3783053A US00219115A US3783053DA US3783053A US 3783053 A US3783053 A US 3783053A US 00219115 A US00219115 A US 00219115A US 3783053D A US3783053D A US 3783053DA US 3783053 A US3783053 A US 3783053A
- Authority
- US
- United States
- Prior art keywords
- ammonium nitrate
- solution
- slurry
- thickened
- mixing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C06—EXPLOSIVES; MATCHES
- C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
- C06B47/00—Compositions in which the components are separately stored until the moment of burning or explosion, e.g. "Sprengel"-type explosives; Suspensions of solid component in a normally non-explosive liquid phase, including a thickened aqueous phase
- C06B47/14—Compositions in which the components are separately stored until the moment of burning or explosion, e.g. "Sprengel"-type explosives; Suspensions of solid component in a normally non-explosive liquid phase, including a thickened aqueous phase comprising a solid component and an aqueous phase
Definitions
- a sensitive gas-entrained water gel explosive is made by mixing at a location convenient to the blasting site a concentrated aqueous solution of ammonium nitrate, nitric acid, sodium nitrate and hexamethylenetetramine and a minor amount of a thickening agent such as guar gum, allowing sufiicient time for the gum to become hydrated and give the maximum thickening effect, then, mixing the resulting thickened solution with solid ammonium nitrate and a minor amount of a fuel to yield a thickened slurry, pumping the thickened slurry and injecting into the exit stream from the pump both a substantial quantity of a gas and a solution which has the eflFe'ct of crosslinking the thickening agent and conducting the resulting thickened slurry through a static mixer.
- Ammonium nitrate in the strictest sense is not an explosive substance. However, it is a compound which undergoes thermal decomposition and if sufficient heat is supplied continuously so as to maintain the thermal dewith other solid ingredients such as fuels, sensitizers, pro- 7 pellants and high explosives in a saturated aqueous solution of ammonium nitrate.
- solid fuels such as powdered coal, sulfur or finely divided aluminum, it has been possible to cause enough heat to be generated during the decomposition of the major part of the ammonium nitrate so as to drive the thermal decomposition reaction to substantial completion.
- a problem encountered with these slurry explosives is that of obtaining sufficient sensitivity, so that they are easily initiated.
- Probably the most common means of obtaining sensitivity has been to include in the composition an extremely flammable fuel such as pigment grade powdered aluminum, or an explosive or propellent substance such as TNT or smokeless powder, which will release enough energy to keep the thermal decomposition going.
- Paint grade aluminum powder is made by lubricating aluminum particles with a substance such as stearic acid and milling these particles into tiny flakes. It has been known for many years that when this type of aluminum powder is mixed with an oil or a hydrocarbon solvent the particles are readily wetted and disperse rapidly, making fairly stable suspensions.
- ammonium nitrate solution prepared by the preferred method is at an elevated temperature, which facilitates mixing therewith a small amount of a water dispersible thickening agent, most conveniently a polysaccharide gum such as guar gum.
- a water dispersible thickening agent most conveniently a polysaccharide gum such as guar gum.
- the process comprises the following steps:
- step (b) Mixing together the pumpable thickened solution of step (a) with solid particles of ammonium nitrate and a minor proportion of a fuel to yield a thickened slurry;
- U.S. Pat. 3,496,040 discloses a class of slurry blasting agents consisting of aqueous solutions of ammonium nitrate, hexamethylenetetramine and a thickening agent, havsuspended therein solid ammonium nitrate and a solid fuel.
- Typical compositions contain at least 15% water, ammonium nitrate, sodium nitrate, hexamethylenetetra mine, a solid fuel such as particulate aluminum and a thickening agent such as guar gum to stabilize the suspension against settling.
- slurry blasting agents of this type by merely mixing the individual ingredients with water, using a major amount of solid ammonium nitrate, solid sodium nitrate and a small percentage of hexamethylenetetramine to prepare the original concentrated solution on which the slurry blasting agent is based.
- heat is absorbed as the ammonium nitrate goes into solution, so that the preparation of a saturated liquor requires a source of heat, thereby increasing the expense.
- the liquor may be acidic, basic or neutral, the pH being readily adjusted by addition of either nitric acid or sodium hydroxide.
- sodium nitrate is added to such compositions as a cheap secondary oxidizing agent.
- a cheaper method of preparing the liquid phase which is used as a base for preparing this class of slurry explosives involves reacting ammonium nitrate with formaldehyde in aqueous solution in a ratio of at least 4 mols of ammonium nitrate per 6 mols of formaldehyde and dissolving therein a quantity of unreacted ammonium nitrate to produce an aqueous solution of ammonium nitrate, nitric acid and hexamethylenetetramine and adding thereto suflicient sodium hydroxide to adjust the pH preferably between 4 and 7 and produce sodium nitrate as a secondary oxidizing agent.
- step (b) Mixing in the solid ingredients
- mixing apparatus which has been designed to mix together dense slurries such as concrete.
- dense slurries such as concrete.
- a concrete mixer 65.3 parts by weight of the pumpable thickened solution obtained in step (a), 34.7 parts by weight of solid particulate ammonium nitrate and 50 parts by weight of a dry explosive consisting of ammonium nitrate particles impregnated with 6% by weight of diesel fuel.
- a dry explosive consisting of ammonium nitrate particles impregnated with 6% by weight of diesel fuel.
- the thickened slurry produced in Step (b) may be pumped in suitable apparatus designed for this purpose.
- suitable apparatus designed for this purpose.
- slurry pumps which are manufactured for the purpose of pumping oil well drilling muds and also there are pumps specifically designed for pumping concrete and grout slurries of various consistencies. Most of these pumps are designed to minimize wear and malfunction caused by abrasive particles in the slurries, so that they are capable of long service with minimum upkeep.
- a peristaltic type of concrete pump such as for example a pump of the type disclosed in U.S. Pat. 3,180,272 is employed. This type of pump delivers a slurry stream with pulsating pressure.
- pulsations are advantageous in the present process because they make it easier to inject other substances into the slurry stream making it unnecessary to use high injection pressures.
- a stream of gas under a pressure of about p.s.i.g. and through another injection inlet located close to the gas inlet there is injected approximately 1.25 weight percent of a solution made up by combining 100 parts by weight water with 10 parts by weight zirconium sulfate, 3 parts by weight chromium trioxide and 3 parts by weight aluminum sulfate.
- This solution has the effect of cross-linking the hydrate polysaccharide gum in the thickened slurry blasting agent composition so that the gum takes on a tough elastic character when the cross-linking becomes complete.
- toughness of the cross-linked slurry depending upon the gas which is injected. Nitrogen, for example, readily produces a much tougher cross-linked gel than air and carbon dioxide yields cross-linked gels of intermediate toughness.
- Suitable cross-linking solutions may be formulated according to the published recommendations of the manufacturers of the gum.
- the injected gas and cross-linking solutions are not evenly distributed in the explosive composition at this stage, as there is a tendency for more injection to take place during the pressure drops than at the peak pressures of the pump output. Thorough mixing and dispersion of the gas are accomplished in the following step.
- the bafiles effect division, rotation, relative displacement and recombination of portions of the stream of viscous fluids in such a way that the mixture becomes more uniform as it passes through the baffle chamber.
- Devices of this type are disclosed for example in US. Pat. 3,286,992 and US. Pat. 3,168,390.
- the motionless mixers are described in Chemical Engineering magazine, pp. 94-96 of May 19, 1969 and pp. 92 and 93 of the issue of Mar. 22, 1971.
- a thickened slurry containing injected gas and cross-linker as described above need only be passed through a suflicient length of static mixer to obtain the desired properties in the final explosive.
- the pressure drop attributable to the static mixer may be only about 40 to 60 p.s.i.
- the diameter of the conduit attached to the pump outlet and the diameter and length of static mixer can be selected to obtain the desired throughput rate, pressure drop and degree of mixing.
- the sensitive gas-entrained slurry basting agent obtained as described above has been found to be a desirable product for the blasting of rock, particularly for making excavations.
- a sensitive gel with higher explosive energy, useful for moving harder rock or for wider spacing of charges may be made by charging to the mixer in step (b) for example 65.3 parts by weight of the pumpable thickened solution obtained in step (a), 30.7 parts by weight of solid particulate ammonium nitrate, 50 parts by weight of a dry explosive consisting of ammonium nitrate particles impregnated with 6% by weight of diesel fuel and 4 parts by weight of particulate aluminum (granular aluminum or chopped aluminum foil).
- step (b) 65.3 parts by weight of the pumpable thickened solution obtained in step (a), 26.7 parts of solid particulate ammonium nitrate, 50 parts by weight of a dry explosive consisting of ammonium nitrate particles impregnated with 6% by weight of diesel fuel and 8 parts by weight of coarse granular aluminum.
- Explosive compositions intermediate in makeup between those specifically disclosed may also be made by the method of this invention. All of these compositions are sufliciently sensitive so that explosion is easily initiated with the use of conventional blasting caps and detonating cord in conjunction with cast primers or dynamite. Furthermore, the method of this invention is broadly applicable to manufacture of aqueous ammonium nitrate slurry explosives of the gel type which are sensitized by microscopic gas bubbles and contain no propellant or explosive substance as sensitizer.
- step (d) thorough mixing and hydration of the gum in step (a) to obtain a pumpable, uniformly thickened concentrated aqueous ammonium nitrate solution; obtaining a pumpable thickened slurry of stable characteristics in step (b) injecting the gas and the cross-linking solution into the exit stream of the pump in step (c) and conducting the resulting stream through a motionless mixer in step (d).
- a process for manufacturing a sensitive aqueous gel explosive comprising the steps:
- step (b) mixing together the pumpable thickened solution of step (a) with solid particles of ammonium nitrate and a minor proportion of a fuel to yield a thickened slurry;
- a process for manufacturing a sensitive blasting gel comprising the steps:
- step (b) mixing together the pumpable thickened solution of step (a) with solid particles of ammonium nitrate, a portion of which particles are impregnated with a hydrocarbon [fuel to yield a thickened slurry;
- a process for manufacturing a sensitive blasting comprising the steps:
- step (b) mixing together the pumpable thickened solution of step (a) with solid particles of ammonium nitrate and a minor proportion of coarse granular particulate aluminum to yield a thickened slurry containing suspended ammonium nitrate and aluminum particles;
- a process for manufacturing a gelled aqueous slurry blasting composition which depends upon a dispersed gas for sensitivity and contains no propellant or high explosive sensitizers, the improvement consisting of gel (a) pumping a thickened slurry comprising solid ammonium nitrate, a minor proportion of a fuel and a thickening agent and injecting into the exit stream from the pump a stream of gas and an aqueous solution which eifects crosslinking of the thickening agent so as to greatly increase the thickening effect and (b) conducting the resulting stream of thickened slurry through a motionless mixer under conditions substantially free from shear to yield a sensitive gas-entrained aqueous gel explosive.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Air Bags (AREA)
Abstract
Description
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US21911572A | 1972-01-19 | 1972-01-19 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3783053A true US3783053A (en) | 1974-01-01 |
Family
ID=22817943
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00219115A Expired - Lifetime US3783053A (en) | 1972-01-19 | 1972-01-19 | Process for manufacturing gasentrained aqueous gel explosive |
Country Status (2)
Country | Link |
---|---|
US (1) | US3783053A (en) |
CA (1) | CA972573A (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3925428A (en) * | 1974-04-08 | 1975-12-09 | Chevron Res | Hydroxy-aluminum nitrate polymer production |
US3927184A (en) * | 1974-04-08 | 1975-12-16 | Chevron Res | Process for producing hydroxy-aluminum nitrate polymer |
US4008108A (en) * | 1975-04-22 | 1977-02-15 | E. I. Du Pont De Nemours And Company | Formation of foamed emulsion-type blasting agents |
JPS5467014A (en) * | 1977-10-08 | 1979-05-30 | Nippon Oils & Fats Co Ltd | Production of water containing explosive composition |
US4701227A (en) * | 1987-02-05 | 1987-10-20 | Loverro Jr Nicholas P | Ammonium nitrate explosive compositions |
ES2074952A1 (en) * | 1993-11-02 | 1995-09-16 | Espanola Explosivos | Explosive composition of the hydrogel type and process for its manufacture |
ES2074953A1 (en) * | 1993-11-02 | 1995-09-16 | Espanola Explosivos | Explosive composition of the hydrogel type and process for its manufacture |
CN110407652B (en) * | 2019-08-19 | 2021-02-02 | 安徽雷鸣科化有限责任公司 | Mixed loading equipment for water gel explosive and control method thereof |
US11427515B2 (en) | 2018-01-29 | 2022-08-30 | Dyno Nobel Inc. | Mechanically-gassed emulsion explosives and methods related thereto |
-
1972
- 1972-01-19 US US00219115A patent/US3783053A/en not_active Expired - Lifetime
- 1972-10-03 CA CA153,072A patent/CA972573A/en not_active Expired
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3925428A (en) * | 1974-04-08 | 1975-12-09 | Chevron Res | Hydroxy-aluminum nitrate polymer production |
US3927184A (en) * | 1974-04-08 | 1975-12-16 | Chevron Res | Process for producing hydroxy-aluminum nitrate polymer |
US4008108A (en) * | 1975-04-22 | 1977-02-15 | E. I. Du Pont De Nemours And Company | Formation of foamed emulsion-type blasting agents |
JPS5467014A (en) * | 1977-10-08 | 1979-05-30 | Nippon Oils & Fats Co Ltd | Production of water containing explosive composition |
JPS5727070B2 (en) * | 1977-10-08 | 1982-06-08 | ||
US4701227A (en) * | 1987-02-05 | 1987-10-20 | Loverro Jr Nicholas P | Ammonium nitrate explosive compositions |
ES2074952A1 (en) * | 1993-11-02 | 1995-09-16 | Espanola Explosivos | Explosive composition of the hydrogel type and process for its manufacture |
ES2074953A1 (en) * | 1993-11-02 | 1995-09-16 | Espanola Explosivos | Explosive composition of the hydrogel type and process for its manufacture |
US11427515B2 (en) | 2018-01-29 | 2022-08-30 | Dyno Nobel Inc. | Mechanically-gassed emulsion explosives and methods related thereto |
CN110407652B (en) * | 2019-08-19 | 2021-02-02 | 安徽雷鸣科化有限责任公司 | Mixed loading equipment for water gel explosive and control method thereof |
Also Published As
Publication number | Publication date |
---|---|
CA972573A (en) | 1975-08-12 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4141767A (en) | Emulsion blasting agent | |
US4181546A (en) | Water resistant blasting agent and method of use | |
US3674578A (en) | Water-in-oil emulsion type blasting agent | |
US4216040A (en) | Emulsion blasting composition | |
US4231821A (en) | Emulsion blasting agent sensitized with perlite | |
US3886010A (en) | Stabilized and aerated blasting slurry containing thiourea and a nitrite gassing agent | |
US3783053A (en) | Process for manufacturing gasentrained aqueous gel explosive | |
US3270815A (en) | Combination hydraulic-explosive earth formation fracturing process | |
US3765967A (en) | Liquid and slurry explosives of controlled high sensitivity | |
US3660182A (en) | Explosive compositions and method of preparation | |
US4008110A (en) | Water gel explosives | |
US3395056A (en) | Inorganic oxidizer salt-alcohol explosive slurry containing an alcohol thickening agent | |
US4756779A (en) | Process for the production of particulate, water resistant explosives based on ammonium nitrate | |
US3660181A (en) | Blasting slurry compositions containing calcium nitrate and method of preparation | |
US3294601A (en) | Hexamethylene tetramine and ammonium nitrate containing explosive composition | |
US3453158A (en) | Fueled inorganic oxidizer salt aqueous explosive composition containing independently dispersed gas bubbles and method of making same | |
US4976793A (en) | Explosive composition | |
US4718954A (en) | Explosive compositions | |
FI62279B (en) | VAT TREATMENT | |
UA75381C2 (en) | Process for manufacturing explosive substances on-site | |
US3390032A (en) | Gelled aqueous slurry explosive composition containing as a gas generating agent a carbonate or bicarbonate with a nitrite | |
US3787254A (en) | Explosive compositions containing calcium nitrate | |
Cook | Explosives—a survey of technical advances | |
KR100508230B1 (en) | Cast explosive composition with microballoons | |
IE42393B1 (en) | Blasting composition containing calcium nitrate and sulfur |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: THERMEX ENERGY CORPORATION 13601 PRESTON ROAD DALL Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:GULF OIL CORPORATION;REEL/FRAME:004354/0001 Effective date: 19841114 |
|
AS | Assignment |
Owner name: GENERAL ELECTRIC CREDIT CORPORATION 100 GALLERIA P Free format text: SECURITY INTEREST;ASSIGNOR:THERMEX ENERGY CORPORATION;REEL/FRAME:004362/0093 Effective date: 19841114 |
|
AS | Assignment |
Owner name: UNIVERSAL TECH CORPORATION, A CORP. OF OK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:THERMEX ENERGY CORPORATION;REEL/FRAME:005324/0468 Effective date: 19900604 |
|
AS | Assignment |
Owner name: THERMEX ENERGY CORPORATION, TEXAS Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:GENERAL ELECTRIC CAPITAL CORPORATION;REEL/FRAME:005424/0260 Effective date: 19900606 Owner name: LSB CHEMICAL CORPORATION Free format text: SECURITY INTEREST;ASSIGNOR:UNIVERSAL TECH CORPORATION;REEL/FRAME:005424/0272 Effective date: 19900801 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED FILE - (OLD CASE ADDED FOR FILE TRACKING PURPOSES) |
|
AS | Assignment |
Owner name: SLURRY EXPLOSIVE CORPORATION A CORPORATION OF OK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:UNIVERSAL TECH CORPORATION;REEL/FRAME:006008/0707 Effective date: 19920107 |
|
AS | Assignment |
Owner name: HOUSEHOLD COMMERCIAL FINANCIAL SERVICES INC., ILLI Free format text: SECURITY INTEREST;ASSIGNOR:SLURRY EXPLOSIVE CORPORATION;REEL/FRAME:006066/0012 Effective date: 19920306 |