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By Alphonce Wikedzi, Mussa D. Budeba, Samwel V. Manyele, Sospeter P. Maganga

The present study provides an overview of the challenges and opportunities in processing complex gold-copper ores. The systematic literature review was conducted using Scopus database and seven-step methodological approach. The study indicates that the major challenges in processing complex gold-copper ores through the conventional cyanidation method include (1) increase in cyanide consumption; (2) increase in cyanide destruction cost; (3) low gold recovery; (4) decrease in adsorption efficiency; (5) decrease in electrowinning efficiency, and (6) difficulties in the measurement of free cyanide concentration in the leaching system. Moreover, the study indicates that several methods have been developed and some have been implemented in the mining industry for processing complex gold-copper ores. This includes ore segregation, pre-aeration, pre-treatment methods (e.g., ammonia), alternative lixiviants (e.g., thiosulfate, thiocyanate, glycine), cyanide destruction methods, and cyanide and copper recovery technologies. The study concluded that using lixiviant mixtures (e.g., cyanide-glycine), pre-treatment with environmentally friendly reagents (e.g., glycine) and the integrated membrane-based process (SuCy process) are new directions in processing complex gold-copper ores. However, more investigations are required to advance these processes to a commercial scale.

Sep 30, 2023

By M. Kane, O&apos

BHP Iron Ore initiated research programs in January of 1995 to develop long term plans for decommissioning of the waste rock material at their Mt. Whaleback operation. More than 2 billion tonnes of waste rock were deposited during the past 30 years. Ultimately, the operators will deposit a total of approximately 5 billion tonnes in waste rock dumps constructed near the open pit. The Mt. Whaleback operation is located in a semi-arid climate adjacent to Newman, Western Australia, approximately 1200km north-northeast of Perth, Western Australia. The primary research program includes the development of technology for the long term performance of the waste rock dumps with respect to vegetation, slope stability, surface runoff, erosion, and water infiltration. This paper focuses on the design and implementation of a cover system to prevent water infiltration to the underlying waste rock. A laboratory program and the soil-atmosphere modelling completed to design the horizontal field test plots are described. The construction of the horizontal surface field test plots are discussed together with the field instruments installed to monitor performance. The key components of the instrumentation program are the design and installation of large scale field lysimeters to measure the unsaturated flow of moisture into the waste rock from the base of the cover layer. The cover system is designed to maximize infiltration during wet periods for subsequent evapo-transpiration while minimizing surface runoff. The result is a near zero net infiltration to the underlying waste material. A key feature of the design is the use of pit run waste material as the cover material. Monitoring is in progress and will continue for at least two annual wet/dry cycles. The optimum cover system should minimize the net infiltration of water to the underlying waste rock while maintaining physical and ecological integrity for long term performance.

Jan 1, 1998

By Michael E. Zellars

The distribution of phosphate in Pliocene-Miocene deposits of the Southeastern United States was controlled by the prevailing geologic setting. For each basin a unique set of conditions in terms of relationship of land mass to shelf, depositional environment and seawater composition, and movement controlled phosphate distribution. Concentration sufficient to recognize the deposits as a resource occurred in lagoons or shallow neritic zones, with clastics and carbonates diluting the section basinward. Each deposit within a basin displays similar metallurgy and lithology, notwithstanding post-depositional alteration.

Jan 1, 1978

By I. Demers, A. Blier, M. Mbonimpa, M. Benzaazoua, B. Bussière

The Doyon Mine in Quebec, Canada, evaluates the possibility of desulfurizing its tailings to produce material to be used as cover for the acid-generating tailings disposal site. Laboratory tests showed that a single-layer cover made of desulfurized tailings placed over reactive tailings can prevent the generation of acid mine drainage. Modeling with the software Vadose/W was used to optimize the design parameters, namely, cover thickness, water table position and residual sulfide content of desulfurized tailings following laboratory work. It was found that the optimal configuration includes a 1-m (3.3-ft) desulfurized tailings cover containing 0.8% S, with the water table kept at the interface between the reactive tailings and the cover. To maintain the cover performance to reduce oxygen flux toward acid-generating tailings even in the event of a long dry period, a sand layer is suggested to protect the cover from excessive evaporation. It is possible to reach the environmental objective for oxygen flux chosen for the Doyon Mine (10 mol/ m2/year) with the protective sand layer, even in extremely dry conditions.

Jan 1, 2009

By Yuanyuan Wang, XUEWEN WANG, Jinzhi Wei, Ligang Wen, Muxin Jia, Zhengyao Li

The abstract discusses the use of disodium carboxymethyl trithiocarbonate (D8) as an effective depressant in the flotation separation of stibnite and pyrite. The study investigates the mechanism behind D8's selective inhibition of pyrite, utilizing techniques like micro-flotation experiments, contact angle measurements, infrared spectroscopy, adsorption capacity analysis, and zeta potential measurements. The findings reveal that D8 physically adsorbs onto both pyrite and stibnite, but its adsorption capacity on pyrite is significantly higher. This adsorption enhances the hydrophilicity of the pyrite surface, hindering the adsorption of the collector and effectively depressing pyrite flotation, while having minimal impact on stibnite floatability.

Mar 14, 2022

By Haydn H. Murray

In 1967 a large kaolin deposit was discovered on the Jari River, a tributary of the Amazon, in the territory of Amapa in Brazil. The kaolin occurs in the Barreiras Series of Pliocene age and is part of the Belterra Clay. The kaolin was drilled and tested, and today a modern processing plant is producing over 150,000 tons per year of high quality paper coating clay. Some of the problems associated with the mine development, processing, personnel, and marketing of this remote kaolin deposit are discussed. The mineralogy and physical properties of the Jari kaolin deposit are also described.

Jan 1, 1981

By Andrew W. Jenike

The first significant studies of problems related to the handling and storage of bulk solids were reported at the end of the nineteenth century. Early work originated from the necessity to store large quantities of grain and was concerned mainly with pressures affecting the structural design of silos and bins. The Janssen formula (about 1898) and the work of Ketchum [1] form the highlights of that period. In more recent years, progress in mechanization, increasing plant capacities, and rising costs of labor have focused the attention of engineers on the problem of gravity flow of bulk solids. A great deal of work has been done with models, and flow patterns obtained in small scale bins have been described in several publications, for example [2, 3]. An attempt to develop a theory of flow of bulk solids was reported in 1954 [4, 5, 61 and presented to the in a paper [7] in the same year. AIME recommended the continuation of this work and, as a result, Engineering Foundation granted a sum of money to set up a Bulk Solids Flow Laboratory. Two and a half years ago the project gained the support of the University of Utah and a laboratory was set up on the campus of the University. This project is now in progress, it has received the support of the American Iron and Steel Institute and of Kaiser Engineers, Division of Henry J. Kaiser Company. The results obtained to date are summarized in this report.

Jan 1, 1959

By J. Astier

The idea of using only one strand for both sintering and cooling of the sinter is not new. In 1952, in the U.S.A. a sintering plant was built at Benson Mine (Star Lake, N.Y.), including : - 68 m2 or 735 sqft (8 wind boxes) for sintering, - 22 m2 or 237 sqft (3 wind boxes) for cooling. In the USSR, a large number of machines have been built allowing for cooling of the sinter on the strand, especially the 4 m (about 13 ft) machines, with : 252 m2 sintering grate area 60 m2 cooling grate area 312 m2 total grate area. However, such ventures did not prove very successful, and the IRSID embarked many years ago on a research program to discover : - what are the problems associated with cooling on a sintering strand ; - what are the possible solutions for industrial plants.

Jan 1, 1974

By Jerry M. Whiting

Greater awareness of the increasing need to develop supplementary energy sources is accelerating us towards many basic decisions regarding future utilization of mined energy materials -- uranium, coal, oil sands and oil shale. The latter material comprises a major potential source of oil which will require creation of unusually large and low-cost underground mining systems. In this paper, the author briefly outlines and analyzes several of the factors which continue to provide the somewhat unique character of oil shale nine planning and mine operation.

Jan 1, 1974

By H. W. Hintze

Coal handling facilities, such as utility plants, coal terminals, ports, manufacturing, processing, etc. Protect themselves against interruptions in coal receipts by maintaining a 60 to 90 day supply in storage. Not too long ago, these storage piles were referred in terms of hundreds or thousands of tons. Today, it is not unusual to have hundreds of thousands or millions of tons in storage. Burn, or shipping and receiving, rates have increased dramatically and storage piles have grown in horizontal as well as vertical dimensions. Fixed systems for delivering and retrieving coal from storage have increased in length and operating capacity and have become highly sophisticated in their operation. With few exceptions, mobile material handling equipment is used to handle all coal beyond the reach of these systems. These machines take excess loose coal from the fixed system to the storage area, place it on the storage pile, compact it, maintain the pile, protect against spontaneous combustion, the spread of fires if they occur, and return the coal to the reclaim system as required, plus many of the small chores around the facility.

Jan 1, 1981

By P. Lopez, E. Wellman, N. Risso, A. Anani

Current machine learning models used for roof fall hazard prediction are mounted on expensive sensors, computationally expensive, or lack the robustness for accurate prediction in the underground mining environment. This research aims to provide a design methodology for a robust, low-cost, deep learning-based algorithm for underground mine roof fall hazard prediction. A data sampling plan is developed to ensure the replicability and robustness of the developed model. In addition, feature engineering and transformation methods are described to identify relevant features for hazard identification. The methodology described here will be used in model development, tested, and implemented as a real-time mobile device application. The new tool will be expected to detect roof fall hazards in real-time and contribute to a crowdsourcing approach for underground hazard detection.

Feb 1, 2023

By G. J. C. Young

The paper describes the replacement of a conventional filtration, clarification and zinc precipitation plant by a carbon in pulp (CIP) electrowinning plant, with the objective of improving the recovery of gold from cyanide leached, acid plant calcines. The discussion covers the early laboratory studies to the design and erection of the full scale plant. Particular emphasis is placed on the problems encountered with commissioning and the strategies which were employed to solve them.

Jan 1, 1982

By E. Woodburn, H. W. Smith, M. C. Fuerstenau, R. Putman

This paper presents a review of developments to date in computer control practice, based in large part on Canadian experience. The basic problem examined is that of stabilizing control; matters considered are control strategies, hardware and software aspects of system implementation, reliability, human factors, and economic results.

Jan 1, 1976

By A. D. S. Gillies

Diesel engine particulate matter pollution is a matter of concern currently in underground mines worldwide. A number of real-time Diesel Particulate Matter (DPM) monitors have been developed in recent years; two of these by the National Institute of Occupational Health and Safety (NIOSH) in the US. One, the D-PDM, is based on an adaption of the successful NIOSH?s Personal Dust Monitor (PDM) unit which is being taken up very successfully for mine respirable dust monitoring. The D-PDM measures all particulate matter within a sub-micron range as classified nominally at 0.8 micrometers by a purpose developed cyclone. The other, the FLIR Airtec, measures the Elemental Carbon (EC) component of DPM by a laser scattering approach. Both instruments have been evaluated underground in robustness and reliability testing in coal mines by the authors. Real time DPM monitors allow greater understanding of the sources and levels of DPM pollution in underground activities. They allow engineering evaluations to determine how conditions can be improved or mining personnel relocated to lower concentration levels. Studies are discussed that examine DPM concentrations from vehicles under varying ventilation conditions. Some of these concern tests undertaken during high activity longwall face moves. They focus on evaluating DPM during the various phases of the face Chock Shield moves. An initiative in some mines has been to limit the number of vehicles in the mining section or panel by the use of a Tag Board or Traffic Controller at the panel travel road entrance to manage exhaust DPM and gases. Diesel tags or tokens are used to control the number of vehicles entering a section or panel and so limit level of pollution. Summation of DPM levels from points monitored throughout a panel demonstrates increasing DPM levels from influence of additional equipment in series within the ventilation circuit. An alternative approach is to invest in underground continuous real-time monitoring of exhaust gases, DPM and section air quantity and integrate this information to determine whether an additional vehicle can enter without exceeding diesel target limit. This optimizes the access of diesel vehicles and replaces the existing manual tag board system. Real-time DPM monitoring allows the industry to pin-point high exposure zones such as those encountered where various vehicles work in areas of constrained or difficult ventilation. Identification of high DPM zones allows efficient modification of mine ventilation, operator positioning and other work practices to reduce underground miners? exposures.

Jan 1, 2012

By F. J. Sotillo

"Scrubbing both horizontal (drum) and vertical (attrition) are considered simple unit operations in the beneficiation of phosphate ores. In general, the operating conditions are fixed at high solids content based on the experience of the engineering or equipment manufacturing company responsible of designing this beneficiation step. Nevertheless, scrubbing is a complex unit operation designed to clean the surfaces of phosphate mineral particles of slimes, break loose weak inclusions or attached particles of impurities, and break aggregates of clayish material. Therefore, it is considered that as high solids content as possible should be used to enhance particle-particle interactions (impact and rubbing) without taking into consideration the rheology of the system. However, scrubbing unit operations design requires studying the balance between the increase of particle-particle interactions with the cushion effect that may occur when slimes, clays and fines decrease the availability of free water increasing the apparent viscosity of the phosphate slurry up to that of a paste consistency. This paper presents data from laboratory tests to determine the best operating conditions for the design of these unit operations based on the highest P2O5 grade obtained with the lowest impurities for different size fractions. INTRODUCTION In the beneficiation of phosphate ores, unit operations such as horizontal scrubbing (drum) and vertical scrubbing (attrition) are considered simple unit operations. Therefore, little attention is given to the design of horizontal and vertical scrubbing during the basic engineering studies, and the detail engineering stage, the manufacturers recommending “standard” units and operating conditions based on their experience. Due diligence of several beneficiation phosphate plants at industrial scale indicates that a deficient scrubbing of the phosphate ore results in significant problems in downstream unit operations, such as classification, clarification, gravity separation, magnetic separation, flotation, dewatering, and filtration. Scrubbing is in fact a complex unit operation designed to clean the surfaces of phosphate mineral particles of slimes (clays and fines), break loose weak inclusions or attached particles of impurities, and break aggregates of clayish material. Two phenomena occur, the particle-particle interaction (impact and rubbing), and the rheological effects of releasing significant amount of fines into the slurry. Therefore, high solids contents are recommended to enhance the particle-particle interactions, which may result in a change in the rheological regime of the system due to the slimes, clays, and fines decreasing the availability of free water. This increases the apparent viscosity of the system up to that of paste consistency resulting in a cushion effect that suppresses scrubbing. Under these conditions, not all fines are release and rejected (deslimed), downstream unit operations being affected by the release of clays, resulting in P2O5 losses."

Jan 1, 2017

By F. Ysla, M. Mendoza

This proposal, based on the CIEMAN Cajamarca - Hualgayoc initiative, focuses on “Transforming Abandoned Mine Lands’’ We aim to study and assess the feasibility of an innovative rehabilitation method. Contaminated soils will be moved from the upper to the lower site, encapsulated with geosynthetic barriers, and covered with topsoil. The decontaminated upper area will be used for planting trees and large-stemmed plants for hiking and tourism, while the lower encapsulated area will support livestock and short- stemmed crops. This study will evaluate the economic viability and multi-use potential of this technique, promoting sustainable land recovery in Cajamarca, Peru.

Feb 1, 2025

By Jr. Winters

The United States continues to be the largest producer and consumer of copper in the world. Table 1 on the following page shows several production statistics for 1974, the most recent year which the non-communist world copper industry might consider a good year, and for 1976 and 1977. In 1974 an estimated 24 percent of the non-communist world's newly mined copper was mined in the United States, and. 87 to 89 percent of that was from the western porphyry coppers. In 1976 U. S. new mine production was down to 22 percent of the non-communist world's newly mined copper, and the percentage of U. S. new mine production supplied by the porphyry coppers had risen to 89 to 91 percent. In 1977 the statistics remained the same as in 1976. U. S. porphyry copper production represented about 65 percent of U. S. refined copper consumption in 1974, rose to 75 percent in 1976, and dropped back to 61 percent in 1977 as imports of foreign copper into the United States began to swell.

Jan 1, 1978

By P. C. Clark

This paper is an overview of the requirements and concerns for minerals and pigments used in papermaking. The first part of this paper deals with mineral or pigment filling in the actual papermaking process. The second part deals with the pigment or mineral properties that are important in today's coating processes.

Jan 1, 1993

By Douglas F. Crickmer

Pocahontas Land Corporation, a wholly-owned subsidiary of Norfolk and western Railway Company, owns a 100,000-acre block of coal lands in Martin, Johnson, Pike, Floyd and Lawrence Counties, Kentucky. These holdings were largely acquired in three major purchases between the years 1942 and 1959. The area is undeveloped and constitutes a part of the coal reserve for future mining. This block, which is principally in Martin County, lies in a triangle formed by the Levisa and Tug Forks of Big Sandy River on the sides with Dewey Dam at its base and the Town of Louisa at the apex. The topography'is typical of eastern Kentucky and consists of steep hills rising from 500 to 800 feet above creek level. There is little level ground in the area. As a matter of fact, some roads are on the creek bottoms with what little bottom land is available in the hollows being utilized for small-scale farming. The steep hills are marked by three separate massive sandstone formations which form cliffs ranging from 40 to 100 feet in height.

Jan 1, 1964

By R. P. Schneider

The Chino mine, concentrator, and smelter are located in Grant County in Southwestern New Mexico. Chino Mines Company is a partnership two-thirds owned and operated by Kennecott Santa Fe Corp., and one-third owned by MC Minerals Corp. (Mitsubishi) of Japan. The Chino Ore Body The Chino ore body is a widely varied deposit of rock types and contains intrusive stocks and sediments. The stocks contain chalcocite in a matrix of quartz, mica, and feldspar. Much of the feldspar is altered to clay. Some of these stocks are enriched with native copper. The sediments contain chalcopyrite associated with gangue minerals including magnetite, pyrite, garnet chlorite, and epidote. The contact of the stock and sediment is heavily altered to chlorite and clay. The stock ores contain economic quantities of molybdenite. The operating work index of Chino ore varies from 5 to 20 kwh/ton and averages 8.5 kwh/ton. The ore head to the concentrator averaged 0.81% copper and 0.010% molybdenum. Fifteen percent of the total copper head exists as nonsulfide mineralization.

Jan 1, 1985