Definition
The most significant sensitiser for commercial explosives has historically been nitro-glycerine. It is manufactured by carefully controlling the temperature during the reaction of a mixture of acids and glycerine and glycol.
Sobrero made the discovery in 1846, and Alfred Nobel developed it to a commercial scale. At 13.2°C, nitro-glycerine, a viscous liquid, freezes to a sensitive, explosive solid. It is too sensitive to handle properly in either form. Consequently, it is transformed into a more manageable gelatinous (plastic) solid by mixing it with other explosive agents and additives to create different kinds of dynamites, adding 8%-gun cotton or nitro-cellulose to create Blasting Gelatine, or absorbing it in Kieselguhr to create straight dynamite (which contains roughly 75% NG).
The kind of explosive created depends on the characteristics of nitro-glycerine and how it is combined with other substances. It is anticipated that the use of explosives based on NG will not rise because of the increased cost of manufacture and the associated pollution management.
A large variety of explosives based on NG are made. They are contained in cylindrical cartridges with lengths varying from 200 mm to 1000 mm, with a diameter of at least 25 mm. It is packaged and kept dry using a variety of paper shells or wrappers. The creation of explosive fumes, water resistance, tampability, and loadability are all significantly impacted by the total weight percentage quantity and type of wrapper.
Explosives based on NG must be handled and stored in compliance with all laws. The oldest stock should be utilised first, and stock levels should be in line with the rate of usage. Cartridges that show signs of degradation where nitroglycerine leaks should be destroyed by a qualified blaster in front of authorities.
Nitro-glycerine is used in the composition of a number of explosives, including dynamites. In the lines below, we will focus on exploring these different explosives, with particular emphasis on their characteristics.
The various NG based explosives
| Explosives | Nitro – Glycerine content |
| Straight dynamites | 60-75% |
| Gelatin dynamite | 90% |
| Blasting gelatin | 85-95% |
| Ammonia dynamite | 30-50% |
| Low-freezing dynamite | 40-60% |
| Cordite | 37% + 60% nitrocellulose |
| Semigelatins | 50-70% |
Bibliography
(Bandhari, 1997)
https://www.nps.gov/parkhistory/online_books/npsg/explosives/Chapter2.pdf
https://www.pbs.org/wgbh/americanexperience/features/tcrr-nitroglycerin/
https://www.nobelprize.org/alfred-nobel/nitroglycerine-and-dynamite/
