5. Any chemical mixtures, compound or device that
reacts at high velocities to liberate gas or heat
causing high pressure and which can be initiated by
a No.8 test blasting cap.
6. • Explosives started 6oo-700 years ago.
• Roger bacon(1214-1292) first described preparation
of black powder
• Potassium nitrate(75%) and carbon(15%) and
sulfur(10%)
7. HISTORY OF EXPLOSIVES
Guns were first used in Battle of Crecy in 1364.
In these guns black powder was used as a gun
propellant.
8. HISTORY OF EXPLOSIVES
The time interval between ignition and blast was a
problem.
Safer method of ignition was invented by William
Bickford of England.
He invented safety fuse.
In safety fuse thin core of black powder is contained in
a cable of jute and string.
10. HISTORY OF EXPLOSIVES
The foundation of modern explosive industry was
laid in beginning of 19th century.
Three men were prominent
1. Edward Howard described preparation of
mercury fulminate (primary explosive)
Hg(CNO)2
2. Schonbein a German engineer produced gun
cotton.
3. Ascanio discovered Nitroglycerin.
11. HISTORY OF EXPLOSIVES
In 1862 Glycerine was transported by Alfred Nobel in
containers with trade name Golonion Oil.
At this time NG was poured from container to hole.
This crude method resulted in accidents and loss of
life.
12. HISTORY OF EXPLOSIVES
Kieselguhr is a form of silica compound of the
siliceous shells of unicellular aquatic plants of
microscopic size.it is porous kind of siliceous
sedimentary rock.
It was used in packing of containers of nitroglycerine
as a cushion.
A container ruptured and NG was absorbed by
keiselguhr.
Alfred nobel noticed it and found that it was more safe
to handle and transport.
He called this mix as dynamite
13. HISTORY OF EXPLOSIVES
In 1950 ammonium nitrate was used as blasting
agent.
In 1960 Watergels were developed
In 1968 Emulsions were introduced
14. MAJOR INGREDIENTS IN EXPLOSIVE
The principal reacting ingredients in an explosive are:
Fuel
Oxidizers
Fuels are carbon aluminum, TNT, smokeless powder.
Oxidizers are hydrogen, nitrogen, carbon and oxygen.
15. TYPES OF EXPLOSIVE AND BLASTING
AGENTS
Nitroglycerine based explosives (Dynamites)
Powder Explosives (ANFO)
Water gels (Slurries)
Emulsion Explosives
16. DYNAMITE
NG are semi pure liquid which is composed of two
organic nitrate esters (Nitroglycerine+Nitroglycol)
This mixture of NG and Kieselguhr when packed in
paper cartridge is called Dynamite.
This product was first introduced by Alfred Nobel.
The NG content of dynamite varies from 5% to 90% of
the composition depends upon the VOD, the energy
released and the water resistance requirements .
17. Nitrocellulose serves as a gelling agent to liquid Easter
to the other ingredients and prevent leaking of
explosive oil.
To balancing the oxidizing salt and fuel by using
oxidizer(Ammonium nitrate).
Sodium chloride is added to lower the detonation
temperature.
To density the NG different ingredients are used such
as starch, sulfur and vegetable gums.
20. STRAIGHT DYNAMITE
It was formulated by Nobel in 1984.
It contain kieselguhr and liquid NG(75%).
Sodium nitrate is added to increase the performance
and make the reaction oxygen balance.
It is used as ditch blasting in wet soils.
21. •In Ammonia dynamite ammonium nitrate was
mixed with charcoal and NG.
•Ammonium Nitrate replaces Kiselguhr and adds
energy, reduces cost, less water resistant.
•It has lower density and higher shock resistance.
•Medium to low VOD.
•Poor to fair water resistance.
22. •Prepared in 1862 by Alfred Nobel.
•Nitrocellulose with lower nitrogen content is
added.
•It acts as an absorbent to retain NG in water.
•It is used in wet blasting operation.
•Gelaprime is its example
•.
23. •It contains a high ratio of nitrocellulose to NG.
•It contains 91 % NG 8% guncotton and 1 % chalk.
•It was called 100% blasting gelatin.
•It has excellent water resistance.
•Sodium nitrate were added to obtain a oxygen
balance.
24. •In this NG is substituted by NH4NO3.
•It high density and velocity.
•Its detonation pressure is high.
•It acts as an excellent booster because of high
energy output.
•It is used for shooting tough rock .
25. •It is cross between ammonia dynamite and
ammonia gelatin.
•It is less expansive than gelatin dynamite.
•It has good water resistance as compare to gelatin
dynamite.
•Geldyne is its example.
26. • It is formed By adding salt and other flame
reducers in ammonia dynamite.
•It is developed for underground blasting
especially for coal mines.
27. •By definition ANFO is a nitrocarbonitrate blasting
agent.
•It is a mixture of ammonium nitrate prills (94%)
and fuel oil (6%).
•The bulk density of ANFO is between 42-50 lbs per
cubic feet.
•The particle size of prills is -6 to +20 mesh.
28. •To initiate ANFO required initiation system and booster.
•Its dead press limit is 1.25cc.
•It has high resistance to water
•It has moderate VOD
•It has large heave and easy to handle and load
•Its cost around $570/ton (1999)
29. SLURRIES
It is an aqueous solution of NH4NO3
and NaNO3, sensitized with a fuel
It is thickened and cross linked by
gelatinous material
Contains more amount of NH4NO3
than watergels
Water resistance is increased by using
gums, waxes and other materials
Slurries has cost more than ANFO
30. WATERGELS
Watergels contains oxidizing salts, fuels and
sensitizers dissolved to form a continuous liquid phase
These are alternatives to dynamites
Thickened and to increase water resistance by
gelatinous materials
Less sensitive more economical and more efficient
than dynamite
31. Less toxic and less hazardous than dynamite
Easy to transport and store
Use in mining industry
32. EMULSIONS
An explosive containing oxidizer dissolved in water
droplets surrounded by an immiscible fuels
Introduced as blasting agent in 1968
It is prepared in the form of water in oil emulsions
It is stabilized by adding emulsifying agents
More efficient, powerful, and stable than watergels
Less sensitive than dynamites to heat, shock, friction
33. Emulsion have very high V.O.D upto 6000
m/sec
High detonation pressure
Less chemical energy per unit weight
compared to ANFO
34. Emulsions are packaged in either paper shells or
plastic film cartridges
35. PERMISSIBLE EXPLOSIVE
Explosives which are designed for mines explosion for
a particular purpose
Use in gassy and dusty atmosphere
Approved by Mine Safety and Health Administration
Developed for underground coal mines
Sodium chloride is used as an additive to decrease the
flame
Should be used soon when taken underground