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Explosive Product Formulation
Achieve: ______
maximize _______
minimize ________
Must have enough _____ to _____
Must have enough ____ to _____
- Achieve oxygen balance
- -maximize explosive energy
- -minimize toxic gases
Must have enough combustible/fuel to react with oxygen (instead oxygen with nitrogen)
Must have enough oxidizing agents (02 carriers) to promote full oxidation of carbon to CO2 instead of CO
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Principal reacting ingredients:(4)
- Fuel
- Oxidizers
- Sensitizers
- Other
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Fuel: reacts with ____
(1+4)
Oxizider
- fuel oil
- carbon
- aluminum
- TNT (trinitrotoluene)
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Oxidizers: yield ____ to ____
(1+3)
oxygen to stimulate combustion
- ammonium nitrate
- sodium nitrate (reduces freezing point)
- potassium nitrate
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Sensitizers:
promote_______ and ______ of
detonation reaction (2 + 4)
intiation and propagation of detonation reaction
- nitroglycerin
- TNT
- nitrostarch (non-headache explosive)
- aluminum
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Other (Principal reacting agents)
(2+2+3)
Gelling agents:
Flame retardant:
Antacids:
- Gelling agents: bind liquids together,
- prevent leakage, water proof
- — nitrocellulose
- Flame retardant: reduce size duration and
- temperature of flame of explosion
- (permissible explosives)
- — sodium chloride NaCI
- Antacids: promote stability
- — calcium carbonate CaCO1
- — zinc oxide ZnO
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Dynamites
Dynamites which are nitroglycerin based explosives are often called ___ dynamites.
Originally they were made of pure nitroglycerin absorbed in _____ or _____.
NG is a blend of two organic _______ ____ namely ______ and _____.
In today’s NG dynamites the proportion of ______ is less than _____, which lowers the freezing point, provides better heat stability and It is cheaper.
They also contain nitrocellulose, oxidizing salts and fuels.
- NG
- clay or sawdust
- nitrate esters namely nitroglycerin and nitroglycol
- nitroglycerin nitroglycol
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Sub-classifications of dynamites (2)
Granular dynamite (Nongelatinous): NG as the explosive base
- Gelatin dynamite (gelatinous) : mixture of NG and
- nitrocellulose--> rubbery waterproof compound
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Granular dynamite (4)
- Straight Dynamite
- High Density Ammonia Dynamite (extra dynamite)
- Lower density Ammonia Dynamite
- Granular Permissible
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Straight dynamite (no ammonium nitrate)
made of NG, sodium nitrate (oxygen balance), wood pulp (absorb NG) and carbonaceous fuels
___ detonation velocities
____ shattering effect
___ detonation temperature
____ sensitivity
_____ flammability
___ water resistance
____ class 3
_____ for underground, used
mainly for ditching application
- High
- High
- Low
- High
- Very high
- Fair
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High density ammonia dynamite (extra dynamite)
High density ammonia dynamites are the most widely used cartridged high explosive.
They have the same composition as straight dynamites except some of the nitroglycerin and sodium nitrate is replaced by ammonium nitrate
____ density
_____ velocity of detonation
____ borehole pressure
____ heaving action
_______ water resistance
______ fume characteristics
_____ for dry blasting in relatively soft grounds.
- Lower
- Lower
- Higher
- Good
- Relatively poor
- lmproved
Preferred
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Low density ammonia dynamite:
Similar in composition to the high density products except more ____ and____ is replaced with ______. ____ strength, useful in ___ rocks.
Granular permissible
Same as ammonia dynamites except ___ is added.
- NG and sodium nitrate
- ammonium nitrate
- Lower
- soft
salt is added (NaCI)
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Gelatin Dynamites
- Blasting Gelatin
- Straight gelatin (gelatin dynamite)
- Ammonia gelatin
- Semi-gelatin
- Permissible gelatin
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Blasting Gelatin
Mixture of ___% ___ and __% ___to form a rubbery cohesive gel.
— They are considered _____.
— Have the ____ detonating velocities.
— Emits large volumes of ______.
— Very ______
Most powerful of all NG based explosives.
- 88-92% NG
- 8-12% nitrocellulose
- water proof
- highest
- toxic gases
- expensive
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Straight gelatin (gelatin dynamite) up to __% ___
Same as blasting gelatin except_____ and
_______ and sometimes _____ is added.
Improved ___
High ____
_______
Fume class - _____ in _____, _____ in ____
High ______ when _____
90% NG
sodium nitrate and carbonaceous fuel and sometimes sulfur
- oxygen balance
- density
- Waterproof
- good to excellent in lower strength poor in higher strength
- velocities of detonation when confined
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Ammonia gelatin: also called special gelatin or gelatin extra
It is a straight gelatin in which ____ and ____ is partly replaced with _______.
Improved _____
Improved _______
Improves _______
Good ________
High ______
High ______
Good for underground work.
The higher strengths can be used as primer.
- NG and sodium nitrate
- ammonium nitrate
- heaving
- oxygen balance
- fume class
- water resistance
- density
- velocity
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Semi-gelatin
They are similar to ammonia gelatin except that more of the __,____ and ____ is replaced by ___ .
They combine the economy of ammonia dynamites with the strength and some of the water resistance of ammonia gelatin.
They are ____ water resistant than ammonia gelatins and ____ economical.
They are ___ water resistant than the ammonia dynamites.
_____ densities
_____ velocities
Often used under ___ conditions and sometimes as primers for _____.
- NG, nitrocellulose and sodium nitrate
- ammonia nitrate
- lower
- lower
- wet
- blasting agents
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Permissible gelatin
Ammonia gelatin or semi-gelatin with ____ added.
salt (NaCI)
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Nitro-Starch Explosives
Non-headache producing high explosives. All of the ___ is replaced by _____. No ____ sensitizer.
Do not ____.
Do not ____.
______________________.
- NG is replaced by nitrostarch
- liquid
- freeze
- leak
- Adaptable to all kind of applications
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Blasting Agents
An explosive products that meets prescribed criteria for ______ to _____ .
insensitivity to initiation
- For storage, any material or mixture consisting of a fuel and oxïdizer,
- intended for blasting, not otherwise defined as an explosive, provided
- that the finished product. as mixed and packaged for use or shipment,
- cannot be detonated by means of a No. 8 test blasting cap when
- unconfined (BAIT).
- For transportation, a material designed for blasting which has been
- tested in accordance with CFR49, Section 173.14a, and found to be so
- insensitive that there is very little probability of accidental
- initiation to explosion or transition from deflagration
- to detonation (DOT)
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Blasting Agents (4)
- Blasting Agent Emulsions
- Dry Blasting Agents
- Watergels or Slurries
- ANFO-Emulsion blends
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Dry Blasting Agents (5)
- ANFO
- Aluminized ANFO
- Densified ANFO
- Heavy ANFO
- Low Density ANFO
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Dry Blasting Agents
No ____ added.
______ is synonymous with dry blasting agent
Most common of all industrial explosives, in excess of __% of use.
ANFO is a mixture of ____ and _____.
Ideal mixture
___% Ammonium nitrate (AN)
___% Fuel oil (FO)
Must be oxygen balanced for ________.
Zero oxygen balance is the point at which an explosive mixture has sufficient ____ to completely ______ all the _____ but have no excess _____ to react with the contained _____.
At zero oxygen balance all gases are ____ and consist of ___, ____ and ____.
water
ANFO
80%
fuel oil and porous ammonium nitrate prills
optimal energy release
- oxygen
- oxidize
- contained fuels
- oxygen
- nitrogen
- harmless
- water, carbon dioxide and nitrogen
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94.3% AN - 5.7% FO (oxygen balanced)
3 NH4NO3 + CH2--> 7 H20 + CO2 + 3N2 + 904 kcal / kg
92.0% AN - 8.0% FO (fuel excess) not enough oxygen
2 NH4N03 + CH2 --> 5H2O + CO + 2N2 + 810 kcal/kg
96.6% AN - 3.4% FO (fuel shortage) excess oxygen
5 NH4NO3 + CH2 —> 11 H2O + CO2 + 4 N2 + 2 NO + 600 kcal / kg
formation of CO and NO is ____(___ ___)
It is generally better to ___ ___ ANFO rather than ____ ____ it.
endothermic (absorb heat)
over fuel ANFO rather than under fuel it
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Ammonium Nitrate Prills
Prills are porous, spherical shaped pellets typically between _____ mesh U.S. standard screen size.
Manufactured by concentrating an ammonium nitrate solution to ___-___%, then _____it. Removal of the moisture during the process produce voids this porosity is carefully controlled.
Prills are also coated to add certain amount of ______ to prevent caking and allow free flow
6 to 20
96-97%, then granulating it
water resistance
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ANFO is the _____ of all explosives and ___ to manufacture. Generally it is _____ and ______ .
- cheapest
- simple
- non-waterproof and free-flowing
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It is hard to give exact characteristics of ANFO. They will vary with: (7)
- fuel oil content and distribution
- prill size, shape, porosity, density and distribution
- charge diameter, affects VOD, min 2 inch and 1 inch for crushed prill
- confinement, affects VOD
- coupling ratio
- z water condition, VOD decreases with water, at 10% water will not detonate
- primer size and type, same size as borehole, multiple for deep holes
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Properties of ANFO
In general ANFO has the following properties:
___ weight strength
___ bulk strength
___ detonation velocity
___ detonation pressure
___ gas production
___ borehole pressure
___ Heaving action
___ to handle, transport and store
Relatively ____
___ to manufacture
Bulk mixing on site and direct borehole loading, makes it ___ and ___ _ ___
- High
- Low
- Low
- Low
- High
- High
- Good
- Safer
- cheap
- Easy
- safe and quick to use
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Problems with ANFO:
___ of fuel oil by ____ or ____ can
result in the generation of _____ quantities of fumes
can react with some _____ (i.e. ___)
not ___ ______
must be ___ _____
____ primed for full efficiency
no ________ in bulk form
- Loss
- evaporation or migration
- hazardous
- sulfide ores (e.g. pyrite)
- cap sensitive
- well confined
- heavily
- water resistance
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Bulk ANFO
Blown (pneumatic) or augered from bulk trucks, can be _____
field mixed
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Bagged ANFO
_____ resistant
____ pressure reduced
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Aluminized ANFO
finely divided aluminum for ____ energy
81.6% AN - 18.4% Al
3 NH4NO3 + 2Al -> 6 H20 + AL2O3 + 3N2 + 1975 kcal/kg
87.6% AN - 2.5% FO - 9.9% AI
6NH4NO3 + CH2+ 2Al --> 13 H2O + AL2O3 + 6 N2 + CO2 + 1320 kcal/kg
increased
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Cartridged ANFO
______ by crushing __% of ____ or adding ____ compounds.
- Densified
- crushing 20% of prill or adding iron compounds
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Heavy ANFO
Mixture of ANFO> __% and ___(in varying %)
Full range of __ depending on %
Varying degree of _______ depending on %
Density between ___ and ___
Weight strength __ than ANFO
Bulk strength between ___and ___ compared to ANFO of ___
- 50% and emulsion
- cost
- water resistance
- 1.0 and 1.35
- less
- 110 and 150 compared to ANFO of 100
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Low Density ANFO
For _____ blasting near ____structures, or blasting ____, _____ jointed or ___ density rocks which requires _____ shock energy a ___ concentration of energy is needed.
ANFO diluted with _____ can be used.
The product is often called ___ or ____.
Size distribution of the polystyrene is _____ the prill.
As low as __% prill by volume can be used
Densities as low as __ or __ can be achieved
_____ based oil is used as fuel
Packaged or bulk with tackifying agent to prevent ______
- controlled
- sensitive
- soft, highly jointed or low density
- minimum
- low
- polystyrene bead
- ISANOL or ANFOPS
- the same as
- 25%
- 0.2 or 0.3
- Vegetable
- segregation
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ANFO Emulsion Blends
ANFO is added to some emulsion explosives to ____ their physical characteristics and ___ the rate of detonation.
As prill concentration ___the water resistance ______
Common blends contain between __ to __% prill
Weight strength between __ to __ compared to ANFO at 100
Densities between __ to __ corresponding to a bulk strength of between ___ and ____.
increases, decreases
30 to 50%
- 1.1 to 1.3, 110 and 155
- 80 to 95
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Water gels or Slurries
They are gelled water-based explosives.
The continuous phase consists of _____ dissolved in water with ____ ingredients suspended by a ____
Requires ____ to ____.
- oxidizing salts
- solid
- gelling agent
chemical or high-explosive sensitizer to detonate
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Watergels or Slurries
Oxidizer salts
-ammonium nitrate
-sodium nitrate
Fuel
Sensitizer
- TNT, smokeless powder, nitrostarch, ethylene glycol mononitrate(EGMN), methylamine nitrate, ethanolamine nitrate.
- Al, air bubbles, monometholamine, micro-balloon or micro-spheres
Water 10-30%
Gums, waxes
Thickener
Gelling agents (crosslinkers)
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Watergel Characteristics
Relatively _____ compared to ANFO
________ in full concentration
Can be __ or ______
Densities between __ and ___
Weight strength ____ ANFO
Bulk strength_____ as/than ANFO
VOD ___ than ANFO for similar charge diameter and confinement
- expensive
- Water resistant
- plant or truck mixed
- 1.0 and 1.35
- close to
- considerably greater than
- greater
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Emulsions
Emulsions are prepared in the form of ____-in-___ emulsions
The ____ phase is composed of a solution of oxidizer salts suspended as microscopically fine droplets surrounded by a continuous fuel phase
The mixture is ____ against liquid separation by an _______
water-in-oil
internal
stabilized, emulsifying agent
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Composition of Emulsions
_____ Phase
.__________
______ Phase
. _______________
. ______________
________ Agents
______ Agents for density and sensitivity control
. _________
. _________
. _________
. _________
- Internal Phase
- . solution of oxidizer salts
- Continuous Phase
- . water-immiscible fuel
- . solid fuel (TNT, SP, AI)
Emulsifying Agents
- Bulking Agents for density and sensitivity control
- . air bubbles
- . glass bubbles
- . resin beads
- . plastic beads
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Properties of Emulsions
___ detonation velocities
. due to extremely ___ particle size
. if Al is added VOD _____
. VOD ___ with ___ in charge diameter
Densities from __ to __
____ detonation pressure
____ water resistance
____ over wide range of temperatures (200-900F)
Used for hard ____, ____, ____ for _____
- High
- fine
- decrease
- decrease with decrease
- 0.80 to 1.35
- High
- High
- Stable
- massive rocks, hard toes, booster for
- ANFO
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Matching Explosives Shock and Heave to Blasting Requirements:
degree of existing fracturing and in-situ block sizes which control the degree of new breakage required
where significant breakage is needed, rock strength and breakage characteristics control the type and amount of explosive energy required
the dynamic properties of the rock mass, which controls the ease with which the rock transmits or absorbs dynamic strain energy
the stiffness or degree of brittleness as opposed to the plasticity of the rock mass which influence its fracture and displacement behavior
the porosity and density of the rock mass controls the interaction with
the explosive gases and the time required for burden movement
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