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Comminution: Energy-Size Reduction Relationships

Search for a consistent theory to explain the relationship between energy input and size reduction in a comminution process has accumulated, over the years, an enormous amount of plant and laboratory data. Although some correlation of these data has been possible for purposes of engineering design and for the advancement of research in fracture, there … Read more

Solvent Flooding

One-third to one-half of the original oil is left in most reservoirs even after thorough gas driving or waterflooding. In contrast, essentially all of the oil contacted can be recovered by flooding with a solvent (a fluid miscible with the reservoir oil). It is not economical to fill a reservoir with solvent since the value … Read more

Grinding with Low Speed Under-Loaded Ball Mill

The small ball mills and rake classifiers in the London concentrator were replaced by one large ball mill and one hydraulic classifier. This new ball mill was designed oversize so that it could be operated at slower than normal speed. The proper operating conditions were established and the results published. In 1953 this study was … Read more

Recovery of Iron Ores Containing Titanium Manganese Chromium and Alkali Metal Sulfates

Most iron ores treated by the R-N direct reduction process yield metallic iron products considerably lower in titanium, manganese, and chromium oxides and alkaline metal sulfates/sulfides than were contained in the original ores. These metallic iron products are suitable as feed stock for the open hearth and electric steel-making furnaces. The elements which are rejected … Read more

Underground Conveyor

The Inland Steel Company operates five underground iron mines in the Lake Superior District. The two largest of these, from the standpoint of productive capacity, are the Sherwood Mine in Iron River and the Bristol Mine in Crystal Falls, both on the Menominee Range of Michigan. It is at these two mines that we have … Read more

Single Stage VS Two Stage Grinding

Homestake crushing and grinding-practice was completely revised during the period of 1951-1953. During the conversion, both crushing, plants at the head frames, the Ross and the Yates, were rebuilt. The flowsheet changes at each plant involved replacing the two 8K gyratories with a single thirty inch gyratory for primary crushing to four inch. The gyratory … Read more

Semi-Automatic Hoist

A Semi-Automatic hoist has been installed at the 2966 station of the Copper Queen mine, since neither the bulk of supplies handled nor the number of men engaged in developing the 3100 level justifies the constant attendance of two cagers and two hoist operators. The connecting service shaft between the 2966 and 3100 levels is … Read more

Low Carbon Steel Continuous Casting

Recognition of the benefits to be gained from the continuous casting of molten steel into finished or semifinished products has been given by scientific minds since the very beginnings of steel plant technology. In fact, Sir Henry Bessemer is credited with the first of a long list of patents issued by the U. S. Patent … Read more

Agglomeration Flotation of Manganese Ore

Beneficiation of the manganese oxide ores at Three Kids Mine near Henderson, Nev., has evolved over a period of years. Commercial application of the process is on a secure basis, and an effective working hypothesis has been formulated to help solve the problems encountered in flotation. Ore Characteristics: Manganeses in the Three Kids ore occurs … Read more

Blasting with Ammonium Nitrate

In giving this subject the “broad-brush” treatment, it will be necessary to generalize on the major points which at the same time will permit me to avoid, to a great extent, any involvement in the purely technical and theoretical aspects of blasting. The practice of theorizing before a new idea is tried has practically been … Read more