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By Neil E. Izatt

The use of Molecular Recognition Technology (MRT), a selective separations technology using specifically designed ligands, has been established as an effective process for removal of metal ions found in many hydrometallurgical, chemical, and wastewater streams. The MRT process has been proven to be highly efficient and effective for indium extraction and recovery from zinc acid leach, electrolyte, chemical process and waste streams. A high percentage of the indium is recovered in a solid product format. MRT has also proven effective for germanium extraction and recovery from similar feed streams. This paper provides the indium and germanium metal recovery flow sheets and analytical results of the metal load and recovery steps.

Jan 1, 2006

By C. Richard Tinsley

As discussed in the economics section of this article, the main processing consideration is whether manganese will be recovered, as this has major implications for reagent consumption. Nodule processing can be classified into three sections; smelting, roasting, and leaching. Many patents have been issued for various stages of these techniques. Since extensive laboratory and pilot plant testing is continuing, it is certain that some companies are close to full-scale commercial processes. Published data does not include all of the possible concepts for nodule treatment. In fact, one may suspect that published flowsheets are those that have been rejected or have since been extensively modified.

Jan 4, 1975

By Barry R. Doyle, James P. Rose, Marius P. Gronbeck

This paper presents a strategy for addressing the hazards of construction of tunnels in ground containing methane. A discussion of the nature of methane includes occurrence underground, and manner of entry into excavations. Means of methane control for underground operations are discussed, including ventilation, monitoring, equipment selection, and personnel training. Principles of ventilation for gas dispersion and removal are addressed. The use of continuous gas monitors, automatic power shutdown systems, and hand-held detectors is discussed. The paper addresses integration of permissible equipment to provide a safe system. Aspects of personnel training are discussed, including maintaining hazard awareness, and evacuation and re-entry procedures.

Jan 1, 1991

Until the early 1960s the world aluminium industry was dominated by six principle pro- ducers with integrated activities from bauxite mining to aluminium production. The growth in consumption of aluminium since that time and the emergence of additional producers has broadened the market for bauxite. In addition the increase in the optimum size of alumina refin- eries has influenced competing metal producers to unite in large joint ventures to minimize alumina costs. From these bases the paper examines present and likely future markets for Australian bauxite; differing marketing phil- osophies for serving those markets; factors influencing successful marketing; and the sources and relative strength of competition which Australia faces.

Jan 1, 1974

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons. ) Position of laboratory assistant in metallurgy, pyrometry, and physical testing is vacant. Salary $80 to $100 to start. Knowledge of metallography desirable. Opening for a mine superintendent familiar with stoking methods on narrow gold quartz veins; also for a. superintendent of a 50-ton fine-grind-in, cyanide mill. College man under 40 preferred. Position in sales department is open for a mining engineer, with experience in mine ventilation and possessing some knowledge of fan design; one competent to lay out ventilating systems to meet various conditions.

Jan 10, 1913

By Paul Soros

Terminal facilities were recently completed at Conneaut, Ohio, on Lake Erie, for the Bessemer and Erie Railroad Co. (a wholly-owned subsidiary of U.S. Steel Corp.) which may become the blue- print for all future coal shipping terminals. Design and engineering of the new facility was by Soros Associates, New York, N. Y. Unlike terminals of conventional design, for example, those at Toledo and Newport News, which load coal directly from the railroad car to the vessel, the new installation passes the coal into temporary storage, loads the vessel from temporary storage and provides alternative reclaiming systems in case of major system failure.

Jan 1, 1966

The reasons for using SFRS, including the way a SFRS performs in comparison to plain shotcrete as a support element in mining tunnels, are discussed. The mechanisms by which steel fibres reinforce shotcrete and the need for specifying performance criteria are highlighted. A description of current testing procedures, including an overview of æquantitativeÆ design recommendations provided from various international authorities, is provided. A summary of international recommendations on suitable æqualitativeÆ performance classifications is also reviewed, including a critique of their suitability. Finally recommendations on the practical considerations necessary to ensure good quality, in-place SFRS, are made, including a calculation method for determining minimum steel fibre dosages.

Jan 1, 1999

By P. Mercille, M. F. Nasmyth, J. G. Cooper

The turn of the century sees considerable activity in the zinc industry for the replacement or expansion of existing cellhouses, and the building of new cellhouses as part of new zinc projects. Aside from the cellhouse technology itself, numerous engineering and construction issues play a major role in the success of a project for replacing or building new cellhouses. The purpose of this paper is to bring to light and to address the engineering and construction factors which go beyond the selection of a cellhouse technology and which remain of key importance in implementing such projects. In addition, some implications of these factors for project costs will be illustrated.

Jan 1, 2000

By William Allen

For the past six years gravity surveys have been used for underground prospecting in the copper mines at Bisbee, Ariz. The primary purpose of the surveys has been to reduce the diamond drilling and crosscutting necessary for exploration. Since many of the orebodies are small, and geologic control is not always apparent, any information that will direct the drilling and crosscutting is highly desirable. Because of extensive development and exploration work in the copper mines at Bisbee, it has been possible to cover more than 630,000 ft of crosscuts on 30 levels with the gravity surveys. In the process the gravity procedures have been refined to a high degree.

Mar 1, 1956

By G. A. Wells

The consumption of barytes in certain paints, polyurethane foams, seamless flooring, glass, brake linings, plastisol gaskets for food containers, and in fluids used for gastrointestinal X-ray examinations relies on the unique properties of barium sulfate. There are no readily available mineral substitutes. Barytes are also the essential raw material for the manufacture of industrially important barium chemicals. High quality barite ore has become scarce throughout the world. Processing ore into quality end products is both capital and energy intensive. These factors have tended to limit availability and increase Prices which have encouraged the use of alternative or competitive materials and restricted market growth.

Jan 1, 1981

By Wadsley MW

This paper gives an overall view of the CSIRO-SGTE computer system for thermodynamic calculations. The basis of the system is the coupling of a large self-consistent numeric data bank of thermodynamic information to a modular set of application programs. These seven programs cover management of data files, calculation of thermodynamic properties for species and reactions, plotting of predomin- ance area diagrams, equilibrium and enthalpy balances for complex processes, analysis of thermodynamic efficiency and the estimation of unknown properties. The data bank contains a wide coverage of species and data types so that the system may be applied to many areas of chemistry and metallurgy.

Jan 1, 1984

By Raymond E. Zimmerman

Abstract-The Swirl Cyclone developed in Japan, although based upon the same principles as the standard cyclones for heavy-media or water-only cyclones for cleaning coal, is novel in that it is invested with the apex on top, discharging rejects at the top, and clean coal at the bottom. It also uses a variable air vent tube for controlling the vortex. Tests conducted indicate that its efficiency is not only as sharp as standard cyclones but it also performs using a much coarser grain magnetite, promising higher magnetite recovery. The author describes the results of tests conducted in Japan on a very difficult coal.

Jan 2, 1978

By T. F. Adams, L. G. Margolin

The Bedded Crack Model (BCM) is a constitutive model for brittle materials. It is based on effective modulus theory and makes use of a generalized Griffith criterion for crack growth. It is used in a solid dynamic computer code to simulate stress wave propagation and fracture in rock. A general description of the model is given and then the theoretical basis for it is presented. Some effects of finite cell size in numerical simulations are discussed. The use of the BCM is illustrated in simulations of explosive fracture of oil shale. There is generally good agreement between the calculations and data from field experiments.

Jan 1, 1982

By A. Guan, K. N. Han, J. J. Kellar, D. A. Boyles

Metal ions associated with effluent streams pose an increasing environmental problem for the mineral industry. Various techniques currently in use to combat this problem including bioremediation, chemical precipitation, and ion exchange are reviewed, and their relative advantages and disadvantages discussed. An alternative technique for metal ion removal, adsorption on surface modified alumina substrates is presented. Alumina surfaces were modified by adsorption of organofunctional silanes, and metal ion removal occurs by chelation of the ion by the adsorbed silane molecules. Experimental data is presented for the removal of cupric ions by this method and is compared to cupric ion removal by adsorption on alumina without prior surface modification.

Jan 1, 1994

By Harold V. Pearce

The fire which occurred in the fall of 1906, at the works of the Boston & Colorado Smelting Co., Argo, Colo., destroyed entirely the gold- and silver-refinery of the plant, and in view of the development of modern practice in the refining of copper-mattes, etc., the management decided that it would be inadvisable to rebuild that part of the works for the continued use of the process which had been conducted therein for so many years as a metallurgical secret. This decision probably removes altogether from the sphere of practice the '(Pearce" method for the separation of gold. At all events, it removes the busi-

Jan 1, 1909

By F. Bourgeois, J. A. Herbst, R. P. King

The ultrafast load cell (UFLC) has proved to be an exceptionally good device for the study of the fundamental processes associated with the impact fracture of particulate material. A new high- sensitivity UFLC has been commissioned at the Utah Comminution Center for the study of low-impact energy single-particle fracture. The force-time histories of individual fracture events have been measured. The force and energy absorbed at crack initiation have been measured at several particle sizes. The mass specific energy for fracture and the associated breakage function have been determined. The distributions of particle breakage energy and particle strength have been measured as a function of particle size.

Jan 1, 1992

By R. L. Blackwood

The solid inclusion cell for absolute in situ stress measurement has been found to give reliable results in coal. The cell is described briefly, along with the methods of installing, overcoring and taking readings in underground coal mines. The validity of the cell performance is demonstrated by reference to the stress-relief curves obtained during overcoring and a three-dimensional B.I.E.M. analysis of the installation to test for stress anomalies deriving from the geometry of the overcoring groove-borehole-cell arrangement. Case studies of two stress measurement projects using the cell are presented for coal mines in New South Wales, Australia.

Jan 1, 1982

By R. S. Rickard, H. D. Peterson, M. C. Fuerstenau, J. D. Miller

The flotation characteristics of the oxide copper minerals, malachite, azurite, and cuprite, have not presented the difficulty for concentration as have those of the copper silicate, chrysocolla. The copper carbonates and oxides respond reasonably well to flotation with conventional collectors, whereas chrysocolla will not respond to flotation with fatty acids or xanthates under normal flotation conditions. In this view then, other reagents will have to be devised to function as collectors for chrysocolla. The most obvious general class of reagents for this purpose would seem to be the organic copper chelating compounds. The utility of chelating agents as collectors in flotation systems has already been demonstrated.1-6

Jan 4, 1966

By R. Hogg

The various sub-processes which, together, make up the unit operation of froth flotation all depend on the characteristics of the feed solids, the solution phase, the air bubbles and the mechanical/hydrodynamic action of the machine. Characterization is obviously necessary for evaluation and process control, but the relationships between characteristics and process response are often unclear. A model-based characterization scheme is proposed in which material and system characteristics are evaluated in the context of simplified models for the individual subprocesses. The general basis for such an approach is discussed using the process of particle attachment and the influence of mineral liberation as examples.

Jan 1, 1989

By C. Klauber, H. G. Linge, W. G. Jones

The carbon-in-pulp process for gold processing depends on the adsorption of dissolved Au(CN)2- from solution onto activated carbon. Our work shows that coconut and peat based carbons have the same mechanism and kinetics of adsorption. There is no contribution to the bonding from carbon-oxygen functionalities on the carbon surface, as has been invariably supposed in all previous theories for the mechanism of the reaction. It is shown that Au(CN)2- is reversibly adsorbed intact on, and parallel to, the graphitic planes of the carbon. The physiochemical basis of the measurement of carbon reactivity for gold adsorption is discussed.

Jan 1, 1989