The co-occurrence of the sulphides of zinc and iron is frequent; blende and pyrite, or marcasite, are found together in important ore bodies which are worked for the value of the contained zinc, and many lead deposits in their lower horizons carry zinc and iron sulphides. Galena may be separated in the wet way from … Read more
Wetherill Rowand Separator Type “E” Separator The machine consists essentially of a belt which conveys the ore between the poles of a series of magnets, so arranged that the belt traverses the air gap between opposite poles; the above figure illustrates the principle of this separator. The lower pole of the magnet is flat, the … Read more
Many classifications based on the method of treatment, on differences in construction, etc., have been suggested to include the different types of magnetic separators; separators with stationary magnets, and those whose magnets revolve; separators in which the ore is attracted directly against the magnet, and those which interpose a nonmagnetic belt or drum between the … Read more
The magnetic properties of certain minerals have long been recognized, and their concentration through magnetism can lay no claim to novelty. A patent was awarded in England on a process for separating iron minerals by means of a magnet in 1792, and in this country a separator having a conveyor belt for presenting ore beneath … Read more
The gradual depletion of high-grade mineral deposits and the necessity for development of lower-grade deposits, together with the increased demand for nonmetallic minerals, has increased the importance of the ore-dressing field during recent years. There is strong need for development of new ore-concentration methods and machines to keep pace with the constant changing of marketing … Read more
The Bureau of Mines investigated the concentration and distribution of precious metals in the various fractions produced from mechanical processing of obsolete military electronic scrap. Whole avionic units, printed circuit cards, and electrical connectors were processed and analyzed. Materials recovered included baghouse lights, wire bundles, magnetics , and metal concentrates from eddy-current and high-tension separation. … Read more
Conventional Magnetic Separator: An Eriez conventional high gradient magnetic separator (HGMS), model EL 20-4, with a 0.058 m canister diameter and a total volume of 1030 cm³ was used. The matrix was a fine grade stainless steel wool. The canister was packed to a 6 percent density with the matrix. The tests followed the recommended Eriez … Read more
The micronized-magnetite coal cleaning technology is based on widely used conventional dense-medium cyclone applications, in that it utilizes a finely ground magnetite/water suspension as a separating medium for cleaning fine coal, by density, in a cyclone. However, the micronized-magnetite cleaning technology differs from conventional systems in several ways: It utilizes significantly finer magnetite (about 5 … Read more
The phenomena of magnetism is well known. The way in which materials respond to a magnetic field can be predicted and the design of magnet systems is now regularly modelled on computer. The real step forward has been in the use of superconducting wire wound magnets that enable much higher fields to be generated. Conventional … Read more
The U.S. Bureau of Mines is conducting an ongoing research project to better understand the phenomena involved within electric arcs utilized in electric furnace steelmaking. With a better understanding of the physical and electrical characteristics involved, dynamic or predictive control of electric arc furnaces may be possible. A mathematical model is presented, but not solved, … Read more