Dynamite (Edited from Wikipedia)
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Dynamite (Edited from Wikipedia) SUMMARY Dynamite is an explosive made of nitroglycerin, sorbents (such as powdered shells or clay) and stabilizers. It was invented by the Swedish chemist and engineer Alfred Nobel in Geesthacht, and patented in 1867. It rapidly gained wide-scale use as a safer alternative to black powder. Today dynamite is mainly used in the mining, quarrying, construction, and demolition industries. Dynamite is still the product of choice for trenching applications, and as a cost-effective alternative to cast boosters. HISTORY Dynamite was invented by Swede Alfred Nobel in the 1860s, and was the first safely manageable explosive stronger than black powder, which had been invented in China in the 9th century. Black powder is now popularly known as gunpowder, because while it is effective as a propellant, it is less suitable for shattering rock or fortifications. Alfred Nobel's father, Immanuel Nobel, was an industrialist, engineer, and inventor. He built bridges and buildings in Stockholm and founded Sweden's first rubber factory. His construction work inspired him to research new methods of blasting rock that were more effective than black powder. After some bad business deals in Sweden, in 1838 Immanuel moved his family to Saint Petersburg, where Alfred and his brothers were educated privately under Swedish and Russian tutors. At age 17, Alfred was sent abroad for two years; in the United States he met Swedish engineer John Ericsson and in France studied under famed chemist Théophile-Jules Pelouze, who had first synthesized nitroglycerin in 1847 with his Italian pupil Ascanio Sobrero. It was in France that Nobel first encountered nitroglycerin, which Pelouze cautioned against using as a commercial explosive because of its high volatility. In 1857, Nobel filed the first of several hundred patents, mostly concerning air pressure, gas and fluid gauges, but remained fascinated with nitroglycerin's potential as an explosive. Nobel, along with his father and brother Emil, experimented with various 1 combinations of nitroglycerin and black powder. Nobel came up with a solution of how to safely detonate nitroglycerin by inventing the detonator, or blasting cap, that allowed a controlled explosion set off from a distance using a fuse. In the summer of 1863, Nobel performed his first successful detonation of pure nitroglycerin, using a blasting cap made of a copper percussion cap and mercury fulminate. In 1864, Alfred Nobel filed patents for both the blasting cap and his method of synthesizing nitroglycerin, which is composed of sulfuric acid, nitric acid and glycerin. On 3 September 1864, while experimenting with nitroglycerin, Emil and several others were killed in an explosion at the factory. After this, Alfred founded the company Nitroglycerin Aktiebolaget AB in Vinterviken to continue work in a more isolated area and the following year moved to Germany, where he founded another company, Dynamit Nobel. Despite the invention of the blasting cap, the volatility of nitroglycerin rendered it useless as a commercial explosive. To solve this problem, Nobel sought to combine it with another substance that would make it safe for transport and handling but yet would not reduce its effectiveness as an explosive. He tried combinations of cement, coal, and sawdust, but was unsuccessful. Finally, he tried diatomaceous earth, fossilized algae, that he brought from the Elbe River near his factory in Hamburg, which successfully stabilized the nitroglycerin into a portable explosive. Nobel obtained patents for his inventions in England on 7 May 1867 and in Sweden on 19 October 1867. After its introduction, dynamite rapidly gained wide-scale use as a safe alternative to black powder and nitroglycerin. Nobel tightly controlled the patents, and unlicensed duplicating companies were quickly shut down. However, a few American businessmen got around the patent by using a slightly different formula. Nobel originally sold dynamite as "Nobel's Blasting Powder" but decided to change the name to dynamite, from the Ancient Greek word dýnamis (δύναµις), meaning "power". HOW IT’S MADE Nitroglycerin by itself is a very strong explosive, but is extremely shock-sensitive (that is, physical shock can cause it to explode), and degrades over time to even more unstable forms, which makes it highly dangerous to transport or use. Dynamite combines 2 nitroglycerin with absorbents and stabilizers, rendering it safe to use while retaining its powerful explosive properties. Nobel's original composition of dynamite consisted of three parts "explosive oil" (as nitroglycerin was called), one part diatomaceous earth as the absorbent, and a small admixture of sodium carbonate antacid as the stabilizer. Ethylene glycol dinitrate was later added to the nitroglycerin to lower its freezing point and keep it from freezing into a slush at low temperatures, which made it unstable, or from sweating out when it thawed. Diatomaceous earth is not usually used today as an absorbent medium and it has been replaced by cheaper media such as sawdust, wood pulp, flour, or starch. Other stabilizers, such as calcium carbonate or zinc oxide, can be used in the place of sodium carbonate. Dynamite is usually sold in the form of cardboard cylinders about 20 cm (8 in) long and about 3.2 cm (1.25 in) in diameter, with a weight of about 1⁄2 pound. A stick of dynamite thus produced contains roughly 1 MJ (megajoule) of energy. Other sizes also exist, rated by either portion (Quarter-Stick or Half-Stick) or by weight. Dynamite is usually rated by "weight strength" (the amount of nitroglycerin it contains), usually from 20% to 60%. For example, 40% dynamite is composed of 40% nitroglycerin and 60% "dope" (the absorbent storage medium mixed with the stabilizer and any additives). The maximum shelf life of nitroglycerin-based dynamite is recommended as one year from the date of manufacture under good storage conditions. Over time, regardless of the sorbent used, sticks of dynamite will "weep" or "sweat" nitroglycerin, which can then pool in the bottom of the box or storage area. For that reason, explosive manuals recommend the repeated turning over of boxes of dynamite in storage. Crystals will form on the outside of the sticks causing them to be even more shock, friction, and temperature sensitive. This creates a very dangerous situation. While the risk of an explosion without the use of a blasting cap is minimal for fresh dynamite, old dynamite is dangerous. Modern packaging helps eliminate this by placing the dynamite into sealed plastic bags, and using wax coated cardboard. 3 ALFRED NOBEL Born in Stockholm, Alfred Nobel was the son of an inventor and engineer. The family was impoverished, and only Alfred and his three brothers survived past childhood. Nobel was interested in engineering, particularly explosives, learning the basic principles from his father at a young age. Alfred Nobel's interest in technology was inherited from his father, an alumnus of Royal Institute of Technology in Stockholm. Following various business failures, Nobel's father moved to Saint Petersburg, Russia in 1837 and grew successful there as a manufacturer of machine tools and explosives. He invented modern plywood and started work on the torpedo. In 1842, the family joined him in the city. Now prosperous, his parents were able to send Nobel to private tutors and the boy excelled in his studies, particularly in chemistry and languages, achieving fluency in English, French, German and Russian. For 18 months, from 1841 to 1842, Nobel went to the only school he ever attended as a child, the Jacobs Apologistic School in Stockholm. As a young man, Nobel studied with chemist Nikolai Zinin; then, in 1850, went to Paris to further the work. There he met Ascanio Sobrero, who had invented nitroglycerin three years before. Sobrero strongly opposed the use of nitroglycerin, as it was unpredictable, exploding when subjected to heat or pressure. But Nobel became interested in finding a way to control and use nitroglycerin as a commercially usable explosive, as it had much more power than gunpowder. At age 18, he went to the United States for one year to study chemistry, working for a short period under inventor John Ericsson, who designed the American Civil War ironclad USS Monitor. Nobel filed his first patent, an English patent for a gas meter, in 1857, while his first Swedish patent, which he received in 1863, was on 'ways to prepare gunpowder'. The family factory produced armaments for the Crimean War (1853–1856), but had difficulty switching back to regular domestic production when the fighting ended and they filed for bankruptcy. In 1859, Nobel's father left his factory in the care of the second son, Ludvig Nobel (1831–1888), who greatly improved the business. Nobel and his parents returned to Sweden from Russia and Nobel devoted himself to the study of explosives, and especially to the safe manufacture and use of nitroglycerin. Nobel invented a detonator in 1863, and in 1865 designed the blasting cap. On 3 September 1864, a shed used for preparation of nitroglycerin exploded at the factory in Heleneborg, Stockholm, killing five people, including Nobel's younger brother Emil. Dogged and unfazed by more minor accidents, Nobel went on to build 4 further factories, focusing on improving the stability of the explosives he was developing. Nobel invented dynamite in 1867, a substance easier and safer to handle than the more unstable nitroglycerin. Dynamite was patented in the US and the UK and was used extensively in mining and the building of transport networks internationally. In 1875 Nobel invented gelignite, more stable and powerful than dynamite, and in 1887 patented ballistite, a predecessor of cordite. Nobel was elected a member of the Royal Swedish Academy of Sciences in 1884, the same institution that would later select laureates for two of the Nobel prizes, and he received an honorary doctorate from Uppsala University in 1893.