The primary mill liner task force was formed in 1977. Its function was to improve the operating costs and milling efficiencies of the ten 8.2-m x 5.5-m (27 ft x 18 ft) wet SAG mills that were operating at the time. The SAG mills are driven by two 3500 HP motors drawing a total of … Read more
Vibratory or oscillating conveyors can be found in all types of industry, handling virtually any granular bulk material. They can be combined with other process functions, such as screening, cooling, drying and de-watering, while conveying. The conveyor can be covered and made dust-tight. Although construction and installation is relatively simple, the engineering and design analysis … Read more
Large scale equipment can reduce both capital and operating costs for concentrators. Large semiautogenous mills can be effectively utilized in big mills but they must be kept fully loaded to take advantage of their great potential. With varying hardness ores, controlling throughput is difficult and careful design must take this into consideration. A variable speed … Read more
Pigments are used in two segments of paper making, as the major component in paper coating formulations and, in small percentages, as fillers in the paper web. Historically, the dominant use has been in coating, however, recent developments have fostered a multifaceted effort to substantially increase the pigment component in the paper furnish. Factors responsible … Read more
Size reduction of ore in the refining process is necessary to liberate or expose the desired component of the raw ore. The geology of the ore deposit and the nature of the ore determine the extent to which the ore must be reduced to maximize the recovery economically. Size reduction of the raw ore is … Read more
Galvanic contact, occurring between electrically conducting minerals in flotation pulps, may affect the nature of mineral surfaces and influence their floatabilities. Rest potential and galvanic current measurements were made on an electrode combination of pyrite and pyrrhotite under nitrogen, air and oxygen aeration conditions, and the results were correlated with their oxygen-consuming characteristics and flotation … Read more
Sodium sulfide is one of the most widely used alkali metal sulfides in the flotation of copper, lead, and zinc minerals in their oxidized form. The sulfidization process, developed in the U.S.A. in 1915-20 for oxide copper minerals flotation, is especially suitable for oxidized lead ores in which the gangue is usually basic. The early … Read more
An in situ leaching geochemical simulator consisting of flow, mass transport, and graphics support programs has been developed. Two dimensional flow in heterogeneous porous media is modeled using a semi-analytic boundary integral technique. This method involves mapping streamlines to straight line segments in the complex potential plane. Leachant concentration and mineral values are modeled in … Read more
There has been a great deal of evaluation and discussion on the economics of semi-autogenous grinding versus conventional grinding circuits. The Henderson Mill, owned and operated by AMAX, Inc., is located 20 miles southeast of Parshall, Colorado. There are minor amounts of galena, chalocopyrite, sphalerite and about 3% pyrite. The major rock type is potassium … Read more
An analysis of screen design options on the operating efficiency of secondary crushing plants has been conducted using a dynamic computer model. The model allows for the simulation of a wide variety of crushing circuits and can be run on either a microcomputer (IBM PC/XT) or a large time-sharing mainframe computer. Size reduction and separation … Read more