Reliable initiation of the explosive decomposition of nitroglycerin was a problem from the start. Black powder safety fuses were tested but gave erratic results, so Nobel returned to a detonator that he had patented in 1867 before dynamite was invented. This was a tin capsule containing mercury fulminate that exploded when struck, and when used […]
Рубрика: The History of Grinding
THE SCIENTISTS AND THEIR CONTRIBUTIONS
Peter Ritter von Rittinger Peter Ritter von Rittinger was an outstanding mineral scientist whose equipment inventions and mathematical descriptions of unit operations established mineral processing as a modern technology (Steiner 2000; Vozar and Kunnert 1972). He was the first to provide a sound mathematical basis for the physics of wet classification and gravity separation processes, […]
Water Wheels, Windmills, and Beyond
GRINDING GRAINS INTO FLOUR For thousands of years, grinding grains to make flour was the primary application of grinding technology. Beginning in about 100 bc, the development of mills driven by water and wind revolutionized the practice of agriculture. Although the importance of bread is underrated today, it is still the main food in many […]
Hammer Mills
In 1830 a patent was issued in United States for a machine …which comprised a wooden box containing a cylindrical drum, apparently made of wood, on which iron knobs or hammers were fastened. The expectation was that this drum, when revolved at 350 rpm, would shatter the rock fed into the box. (McGrew 1950) This […]
Tumbling Mills
By the middle of the 19th century, the need for better fine-grinding mills had become apparent. Stamps driven by steam engines had limitations on how fine they could grind, particularly on the size of the screens used to remove the desired product from the breaking chamber and keep the oversized material in the chamber. Querns […]
Classifying Liners
Figure 7.18 shows three types of classifying liners. As clinker grinding mills increased in length, it became necessary to devise a system by which the coarse balls were continually thrown back to where the coarsest particles of ore were at the feed end of the compartment. Hardinge had designed his “tricone” mill for this purpose, […]
BALL MILLS WITH SHELLS MOVING AT HIGH SPEEDS
Vibrating Mills One method of keeping balls in motion so that they will collide and break particles trapped between them is vibration, and a vibrating ball mill was developed and patented in Germany in the 1930s. Vibrating ball mills are either vertical or horizontal and can be used as continuous flow or batch mills, and […]
ANFO: POWERFUL AND SAFE
As Table 10.1 shows, there was a spectacular rise in consumption of ammonium nitrate explosives during the 1960s. This was the start of the ammonium nitrate-fuel oil (ANFO) era in industrial explosives, which is expected to continue well into the future. Ammonium nitrate was made by J. R. Glauber in 1659 (DuPont 1980). Its explosive […]
Friedrich Kick
Friedrich Kick was born in Vienna in 1840. After graduating from the Vienna Polytechni — kum in 1862, he became professor of mechanical technology at the Technical University in Prague, Bohemia, where he worked from 1865 to 1892, including three terms as rector. From 1892 to 1910, he was a professor at the Technical University […]
WIND POWER FOR GRINDING
Historically, the wind has also been an important source of renewable energy for driving grinding mills. “Crude vertical-axis panemones have ground grain in the Afghan highlands since the seventh century” (Gipe 1995). Panemones had walls to direct the wind past vertical sails that were attached to a rotating axle, as shown in Figure 4.7. Windmills […]