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By Frank L. Bazzanella

Se presenta una breve introducción de la concentración gravimétrica, incluyendo alguna discusión sobre los minerales mas comunes recuperados normalmente. Se mencionan las consideraciones importantes para el diseño básico de una planta de concentración y se presentan cuatro esquemas de flujo sobre las operaciones más corrientes. Las plantas estudiadas en detalle incluyen: "Climax Molybdenum Co. By-Product Plant" y "Canada Tungsten Ltd. Plant". Las plantas brevernente reseñadas incluyen: "Palabora Mining Co. Uranium Recovery Facility" y "Bridge Hill Ridge Heavy Mineral Recovery Plant of Mineral Deposits Ltd."

Jan 1, 1982

Mine managers need useful data to support production and maintenance decisions; for example, to evaluate the performance of replacement components. Today, managers rely solely on past experience, supervisors, opinions, and time studies. Our paper describes the concepts and algorithms we are developing for an automatic, intelligent decision support system (IDSS) that will aid managers by reducing and analyzing large amounts of, monitoring system sensor data and report only key production and maintenance information.. IDSS contains a pattern recognition, subsystem (IDSS/PRS) prototype to report graphical trends in traditional time study elements. We are designing. and prototyping a knowledge representation subsystem, using Knowledge Craft Tools, that will learn and adapt to the dynamic mine environment and reason about the recognized patterns using representations of manager's knowledge, equipment, capabilities, and mine layout and operating procedures. This subsystem will reduce, large quantities of time study type information to key issues that interest different managers.

Jan 1, 1989

By Steven A. Moreno

Geochemical returns from commercial analytical laboratories are often delayed because of postal and other bulk distribution inefficiencies. Consequently, minerals exploration programs are handicapped due to insufficient time for treatment, analysis, and diagnosis of the data. The minerals industry lacks a system for rapid transmission of geochemical data which allows immediate entry into statistical and plotting routines. Over the past three years, Houston International Minerals Corporation (HIMCO) has developed a computer-based system to receive, treat, and distribute geochemical data. In the past two years, Bondar-Clegg (Denver) and Chemex (Vancouver) have developed systems to transmit' data directly to HIMCO via the world-wide Boeing Computer Services (BCS) network. The main benefits to HIMCO have been ten less days for reporting turnaround, ten less days for keypunching, less data handling, accuracy. The benefits to the laboratories have been improved in-house data management, reporting, and HIMCO's increased geochemical activity.

Jan 1, 1982

Relatively few longwall mines in the U.S. operate under multiple seam conditions where the two seams are less than 200 ft apart. This paper describes the experience of six that do. These operations are located in PA, WV and UT, and include examples of both undermining and overmining. Some operate above or beneath their own workings, others are in historic mining districts and must contend with abandoned mines that are decades old. The lessons that these mines have learned cover a broad range of topics, including: • Whether to stack gateroads or place them under old gob areas; • How to size pillars and select artificial support to cross longwall stop lines; • How to use yield pillars to minimize multiple seam stresses and coal bump potential, and; • When to anticipate the creation of pathways for gas, water, or oxygen between current and abandoned gobs.

Jan 1, 2007

By Scott Jones, Tony R. A. Durkac, David W. Stephens

Williams Mine was considering spending a large amount of capital to install a pumping system underground to rid the mine of slimes; with the introduction of Delvo Stabilizer this challenge would be met. This paper will address the process to introducing the Delvo Technology into the Cemented Roddill Program. Some areas that were worked on included: testing of the mix design, bet dosage rate for an economical solution, temperatures at different levels of the mine, the amount of time needed once the grout was put to sleep, preventing plugs in the delivery system A controlled dosage that gave the Operator a 12 hour window of flowable material was developed and an added feature to the introduction of Delvo was also noted; an increase in MPa strength over the design. Collectively with the help of operators at the batch plant and the underground miners involved with the program all concerns where addressed and all goals met. A cost effective program was implemented thus increasing productivity, preventing costly plugs, and improved the actual maintenance on the entire delivery system, which included the batch tanks, aggitator tanks, all pumps required in the system and of course reducing buildup of slimes at the cones.

Jan 1, 2001

By Chris Mills

El papel de la separacion gravimétrica en la industria minera es brevemente considerado en perspectiva. Las pruebas e intentos de laboratorio y mineralógicas para el diseñio de los procesos gravimetricos son examinados poniendo especial énfasis en la selección de la tecnologia del proceso. Es tratado y comentado el material disponible en equipos para pequeña escala y trabajo de pruebas-piloto, particularmente en relación a la escalacion y a la adquisición de datos precisos y fiables. El transporte del comportamiento de los datos desde la planta piloto a la planta a escala es igualmente explicado. Son resefiados todos los tipos de equipos a escala total existentes para la separacion gravimétrica, poniendo de relieve las unidades de alta capacidad. Es considerada la disposicion de la planta y la seleccion de 1os equipos auxiliares.

Jan 1, 1982

By G. Gaidajis

For the environmentally safe management of the sulphidic waste rock produced from the Stratoni mining facilities, TVX Hellas has examined, within the frame of the funded European research program ROLCOSMOS, the effectiveness of an alternative rehabilitation scheme involving the segregation of the sulphide rich components of waste rock and the engineered application of alkaline additives. The examined waste rock management scheme was evaluated with laboratory test work followed by pilot-scale field applications. In this paper, the results from the two-year monitoring period of the pilot scale application are presented.

Jan 1, 2002

By S. K. Mukherjee, A. W. Laurito, M. M. Singh, N. I. Jayaraman

This paper describes the application of foam to control respirable dust in a double-drum longwall mining section. The feasibility of injecting an adequate quantity of foam through the shearer drum was initially established in the laboratory. Thereafter, underground testing of the foam system to determine its effectiveness on an active operating longwall was conducted in a mine in West Virginia. The foam system proved superior to the water spray system. The details of the laboratory and field investigations, the results obtained, and the degree of acceptance of this system by the mining company are discussed in this paper.

Jan 1, 1987

By B. Lin, C. Tang, Z. Chen

Earthquakes, underground impact pressures and rock bursts all produce acoustic emissions. The rate of these emissions can be used to describe rock instability. In this study, it was found that acoustic-emission rates obtained by simulating a twin sample (rock-rock) model could be used to indicate the acoustic-emission-rate characteristics during rock instability. A computer simulation and two case studies support this conclusion.

Jan 1, 1997

By V. F. Swanson

A mathematical model for free and hindered settling of minerals was developed. This paper describes how to apply the model in designing systems, such as fluidized bed, elutriation, mixing pumping systems, involving solids and fluids.

Jan 1, 2000

By Russell G. Slayback

Feasibility investigations for prospective gold mines too often neglect to consider ground water. Simple observations and tests during drilling exploration can provide useful data on probable water conditions. As the prospect becomes more serious, more detailed investigation of ground water and dewatering needs may be warranted. Ignoring ground-water conditions can lead to costly mistakes.

Jan 1, 1987

By I. Toromanoff, F. Habashi

The transformation of a low-grade titanium slag into synthetic rutile or synthetic anatase can be enhanced by attrition grinding.

Jan 1, 1987

By Chen Ziming, A. Burkert, A. L. Mular

A mechanism has been proposed for autogenous grinding that involves three distinct types of breakage: self impact breakage, media breakage and abrasion. Based on this analysis a mathematical model and an autogenous grinding simulator have been developed. Using pilot plant data fitted to the model, the simulator was tested and employed to examine both the scale-up problem and the effect of feed size distribution on performance.

Jan 1, 1995

By Bruce D. Hansen

The complexity of large geographically diverse or multicommodity mining companies requires a corporate structure, which provides the maximum long-term effectiveness. Structure models exist along the spectrum of centralization to decentralization. This paper examines the trade-offs of flexibility, cost, decision making, consistent strategies, and corporate control associated with different structural models as applied to mining companies. The mining industry typically lends itself to a business unit model. However, the degree of decentralization depends on size, proximal operations, technical complexity, product mix, geographic spread, mining methods employed, and the inherent capabilities of an organization.

Jan 1, 2001

By A. R. Garcia, A. S. Myerson, W. R. Ernst, J. D. Carruthers, M. D. Franke, L. H. Hilzik

A method for removing nickel and vanadium contaminants from spent HDS catalysts involves pretreating the catalyst with H2S followed by extracting the metals with an acidic solution of ferric ion. The ferric ion solution alone removes significant amounts of active ingredients, cobalt and molybdenum; however, by pretreating with H2S, the extraction becomes more selective for removal of Ni and V.

Jan 1, 1988

By Kal V. S. Sastry

Mathematical and expert system models are being used extensively for mineral process engineering; nevertheless, standardized methodologies for their computer implementation do not exist. In meeting this need, this paper introduces the concept of a process software model, or more specifically an object-oriented software model, and presents a detailed methodology for its development involving software model specification and development. These software models provide a formal basis for the subsequent design and construction of software objects corresponding to the real world process objects.

Jan 1, 1995

By C. E. Jordan, B. J. Scheiner

The Bureau of Mines conducted research on the flotation hydrodynamics of fine particle flotation to improve the flotation efficiency in our domestic minerals industry. The turbulent fluid velocity profile was measured in various flotation cells at different levels of dissipation energy. The importance of dissipation energy and bubble size within the flotation cells for the flotation response of a chalcopyrite ore was evaluated. Both increased turbulent fluid flow and fine size bubbles improved the flotation rate of fine size chalcopyrite particles.

Jan 1, 1989

By Hugh W. Rimmer

The design of comminution circuits and the evaluation of alternatives should be based on state-of-the-art equipment and appropriate design criteria - considerations that are often neglected by today's designers. This paper critically reviews common circuit designs, evaluates various alternatives for difficult-to-treat ores, and discusses the factors that should be considered when developing new plant designs or auditing existing plant performance. Data obtained from laboratory, pilot and plant-scale test work on a wide range of ores and circuits are used to justify the author's conclusions.

Jan 1, 1995

By Joel Lenz, Warren Hood, Jackson Jenkins

Whole ore or other process streams are being transported from mines to remote processing facilities for multiple reasons, such as improved project economics, maximum utilization of capital, and minimization of environmental risk. Case studies will be presented from a variety of operations. Glenbrook Nickel processes ore from their deposit and receives ore from New Caledonia, crushes and dries the ore, and transports it inland to the smelter. The Mule Canyon and Rosebud ore bodies truck-haul their ores to the Lone Tree and Twin Creeks processing plants. Pegasus Gold hauls their Diamond Hill ore to their Montana Tunnels facilities, and Sierrita pumps solution to an existing tank house 8 miles away for electrolytic recovery.

Jan 1, 1998

By J. A. Frew, G. I. Orrock, R. M. Glen

The zinc flotation circuit was sampled to provide sized information on its metallurgical performance. A good balance was obtained and the roughing, scavenging, cleaning and regrind sections were assessed. Substantial losses of sphalerite occurred in all sizes. The limitations were poor recovery in the cleaning section which resulted in substantial recycling of 15-30µm sphalerite and iron sulphides, and inability to float +38µm sphalerite in the roughers. Regrinding increased sphalerite recovery by 7% with no loss in grade. Liberation measurements enabled balances for six size fractions to be calculated and the role of liberation on the metallurgical performance was assessed.

Jan 1, 1993