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By J. Kenneth Wittle

The DC Graphite Melter has been shown to be capable of processing radioactive waste materials. The process is characterized by its high temperature capability and operation in a closed system. From an environmental perspective, the control of emissions coupled with destruction for hazardous organic materials is mandatory. These same characteristics may be applicable to the minerals processing industry. Under normal operation, the system reaches temperatures for nominal operation of 1600°C, with an arc temperature in the order of 5000°C. The system temperature is determined by the melt temperature of the material being processed. In testing of a 750 lb/hour unit, temperatures of 2200°C were reached. Current focus is on finding waste treatment and metals recovery opportunities in the metals processing industry for his innovative technology.

Jan 1, 1999

By Pierre Dosmond

In ore mining technology, the loading and hauling operations are undoubtedly the area where the most spectacular progress has been made during the last twenty years. I shall draw some examples from the Eastern France iron ore mines which I how well and whose production of 62 million tons for 1962 and 1963 constitute a worthwhile experience worldwide. The iron ore deposits of Lorraine are of sedimentary origin. They contain many mineralized horizons with workable seams situated from 330 to 830 ft. in depth. The dip of these seams is generally less than six percent. Their thickness varies from 6 to 23 ft. All seams are not workable throughout the whole area of occurrence, but in some mines there are five mineable seams in the same vertical section, with from 5 to 20 ft. of barren ground intervening between them. The iron content of the mineral varies from 28 to 36 percent. Specific gravity of the ore is 156 lb. per cu. ft. m place and 100 lb. per cu. ft. blasted. Reserves of iron ore in the Lorraine region are estimated at six billion tons with an iron content of more than 28 percent. These mines operate by means of rooms and pillars process, with pillar robbing; the final recovery is very good and averages 90 percent. Some years back, competition from richer, imported ores incited these mines to make constant efforts to increase their productivity and reduce mining costs, thus placing them in a leading position in mining technology, as evidenced by the dramatic evolution of their output per manshift (Figure No. 1).

Jan 1, 1970

By C. Menidiatis

The first cement plant of TITAN Cement Co was founded in Elefsis in 1902. It was the first cement industrial facility to operate in the Balkans and in the Eastern Mediterranean region. Currently have four cement plants in Greece producing 5.4 million tons per annum, and 25 ready-mixed concrete sites producing 1.4 million m3 annually. It has a total of 20 quarries, 14 of which are producing materials used in the making of cement while the remaining six produce aggregates used in the production of ready-mixed concrete. All plants in Greece are accredited for ISO 14001. The restoration of quarries began in 1976 at the company?s limestone quarry of the Patras plant, and was soon extended to all quarries. At that time, a department responsible for all environmental issues was established. To date, over 700.000 shrubs and trees have been planted and maintained at quarries, plants and ready-mixed concrete facilities, while over 100,000 trees have been donated to municipalities, communities, customers and to the Greek state.

Jan 1, 2002

By Paul D. Tomlingson

Will Rogers unwittingly commented on the essence of evaluations when he said: "We don't know what they don't know!" In so doing, he explained why managers have an obligation to verify that their personnel really know what is expected of them. Rogers further stated that "What we know may not be so!" Here, he suggests that managers must establish the correctness of facts on which they make decisions concerning the future of their organizations. Yet, there are some managers who may not have considered this basic wisdom. These are perhaps the ones who shun a solid, fact-finding evaluation. Instead, they trust to guesswork as a basis for attempting improvement. Without realizing it, they may be making incorrect decisions harmful to the very organization they are trying to improve. Unfortunately, an attitude of avoiding evaluations often permeates whole organizations when their managers fail to appreciate their importance. Recently, the following was found prominently displayed in the office of a maintenance manager. Regrettably, the facts of a subsequent evaluation established how imprudent his attitude was:

Jan 1, 1991

By Daniel P. Coughlin, Robert C. Thomas, Christopher S. Romanek, Kristian W. Paul

Two separate constructed treatment wetland (CTW) systems receiving the same metal contaminated, acid sulfate water over different lengths of time and at different rates were evaluated for metal attenuation. Both wetlands are the alkalinity generator portion of a succesive alkalinity producing system (SAPS). Sequential extractions are employed to determine phases of metal removal. Results indicate that Fe, Al, Zn, Ni. and Cu accumulate in the organic substrate over time. Manganese accumulates initially, but is not retained in the system over time.

Jan 1, 2000

By K. Eric Livo

The Front Range Infrastructure Resources Project (FRIRP) of the U.S. Geological Survey (USGS) is currently using Landsat Thematic Mapper? and air- borne-visible-infrared-imaging-spectrometer (AVIRIS) data along with planned thermal-infrared data and interferometry-synthetic-aperture radar (IFSAR) data to assess the industrial-minerals quality and quantity along the Colorado-Wyoming Front Range Urban Corridor and to characterize surrounding areas. Landsat? satellite data show synoptic views of the corridor, which may readily be used to identify potential regions of permissible terrain, such as river drain-ages, pediment surfaces, upturned lithology, and bed- rock exposures, where various types of deposits may occur. Descriptive models of these deposit types are used to define the physical features that need to be recognized and characterized. In the case of Landsat? data, the measured light is either reflected or partly absorbed by surface materials, depending on the wave- length of the light, which allows coarse mineral classifications to be made.

Jan 1, 1999

By G. Trusler, P. Dama, C. Buckley, C. Jänisch

In the 1990s, Cleaner Production (CP) approaches were successfully introduced to a number of industrial sectors in South Africa. Building on this success, the South African Water Research Commission has commissioned a 3-year study to investigate the use of CP and its related set of environmental assessment and management tools in the mining industry. A scoping study is being carried out on the current knowledge of CP approaches being used in the industry, as well as the proactive and preventative measures being undertaken. One of the significant findings of the scoping study is that distinct differences exist between the larger global companies and the smaller local companies. Being a water research project a key focus area of the project is to reduce the impacts related to mining on the South African water resources. Some of the significant water related threats identified include acid mine drainage, the shortage of the resource and the effects of inter-mine flow.

Jan 1, 2005

By J. R. Hindman

The vermiculite review arrived too late for the June issue. In 1992, production of commercial vermiculite in the United States increased 1 % to 170 kt (187,000 st), according to the US Bureau of Mines. The estimated value of vermiculite concentrate was $13.6 million, yielding an average value of $80/t ($72.50/st). Vermiculite is used in several physical forms. Use of the thermally exfoliated product include light weight aggregates, horticultural growth media, thermal insulation applications and absorbents for spill control and liquid waste containment. The untreated commercial concentrates are used as intumescent fillers in plaster board, gaskets and paints. Several chemically modified vermiculite products include clay-sized dispersions and granules for treating flue gas. South Africa was the only major foreign source of vermiculite used in the United States. It exported about 40 kt (44,000 st) to the United States last year. In 1992, Palabora Mining Co. began processing vermiculite in a new beneficiation mill at Phalabowra. It produced about 164 kt (181,000 st). Minor sources of foreign vermiculite concentrates consumed in the United States included about 140 kt (154,000 st) from China. Brazil also exports some concentrate to the United States.

Jan 1, 1993

By C. H. Bucknam

A suite of ore and waste rock materials was selected for the interlaboratory testing of combustion-infrared ("Leco") methods used to estimate carbonate and sulfide minerals present in test materials. The objective of the study is to develop ASTM standard methods to be used for metallurgical characterization of ore, acid drainage prediction for ore and waste during ore body evaluation, and for ore and waste control during the active mining of ore deposits. The results may be interpreted for classification of the materials according to their carbonate-sulfide or acid-base characteristics based on net carbonate value (NCV). The test materials were processed by x-ray diffraction and x-ray fluorescence (XRD-XRF) at Newmont Metallurgical Services (NMS) to obtain a semiquantitative mineralogical composition. Results of the interlaboratory testing for total carbon-sulfur, pyrolysis loss carbon-sulfur and hydrochloric acid residual carbon¬sulfur are compared with the mineralogical composition to aid in interpretation of the NCV classifications of the samples.

Jan 1, 2002

By Anthony G. Fonseca

About 45% to 50% of the coal mined in the United States passes through coal preparation plants. East of the Mississippi River, this number increases to about 75% to 80%. Although the cost for coal preparation is worthwhile to some, the coal industry faces the challenges of continuing downward pressure on the price of coal and the impact of new environmental regulations. Coal preparation is an effective process that achieves 75% to 80% ash reduction, 15% to 80% trace element reduction and 85% to 90% Btu recovery. It is less effective for pyrite reduction (35% to 70%) and on-line operating time (40% to 60%). It also suffers from obsolete control systems. In coal preparation, raw coal is modified to a more preferred form to enable its use. The methods used to achieve this modification must be cost-effective and appropriate to the raw coal, the scale of production and the end-user requirements.

Jan 1, 1995

By Akira Usui

Ferromanganese crusts on topographic highs in the western Pacific Ocean are believed to be potential resources of cobalt, nickel and platinum. Earlier shipboard geological and geophysical studies by Japanese organizations have focused on mapping of distribution of thickness and metal contents of the deposits when estimating the total reserves. This paper summarizes our attempt to obtain more feasible data of distribution patterns and configuration of the deposits which are important parameters for resource evaluation at some seamounts in the South Pacific Ocean. Morphology of the seamounts and micro-topography of the sea floors are described using shipboard acoustic remote sensing, deep-tow sonar images, and TV/camera. [ ]

Jan 1, 2008

By R. Mohr

Storm water runoff from mine facilities such as haul roads, waste disposal sites and ore bodies have become recognized as the primary facilities associated with non-point source drainage. Depending on the ore body, facility design and geographical setting, nonpoint source drainage can cause pollution impacts to local surface and ground water resources. Non-point source impacts from surface mine drainage have become an important regulatory issue for the mining industry. Implementing non-point source drainage control plans that prevent impacts to water resources can be accomplished cost-effectively with moderate labor requirements. Design considerations for plan development must incorporate parameters including contributing drainage area size, slope, flow velocity, vegetation characteristics and soil scour velocities. The success of non-point source drainage and erosion stabilization planning is based on implementing control measures that dissect drainage patterns, reduce flow velocities and disperse runoff towards sediment control sites. Interim and long-range drainage control measures should begin during exploration activities. Regulatory legislation addressing non-point source pollution sources was enacted as amendments to the Clean Water Act (CWA) in February 1987. The legislation required states to initiate non-point source pollution control programs.

Jan 1, 1991

By J. Nelsen

Social License to Operate continues to emerge as a paradigm fundamental to sustainable mineral resources development. It relates to a set of concepts, values, tools, and best practices that represent the view of reality held by each participant (industry and stakeholders). It enables a forum for negotiation through which all parties involved are heard, understood and respected. The exploration phase of the mine life cycle is generally the initial contact with local communities and forms the cornerstone for effective communication and trust building. This paper presents the development of a mineral exploration template, based on field studies, aimed at assisting exploration personnel to establish effective communications and engagement with local communities within a process to build a Social License. The template aims to provide practical assistance in conducting situational analysis - a process of examining and mapping a situation, its elements and their relations - in order to acquire knowledge and understanding of a project, locale and region. Situational analysis is the ?full situation of inquiry?, going beyond just ?knowing the subject? to being fully situated. It forms the initial foundation for a planning process presented in the paper that prepares for a strategy of initial engagement and consultation.

Jan 1, 2007

By L. W. Saperstein, M. C. Radomsky, D. L. Passmore, J. D. Bennett

About 60 small surface coal mines in Pennsylvania participated in a program designed to improve safety performance in the workplace. The method involved the use of safety sampling and observation to assess the degree of safety exhibited by workplace behavior and conditions. Data were collected through the use of on-site safety instruments covering seven major occupational positions typical of small surface mines. Workplace events observed (acts and conditions) were assigned a hazard classification. Feedback was initiated to improve safety performance in areas failing to conform to appropriate safety standards. Results suggest that the variety of unsafe acts and conditions associated with the companies observed are extensive. Further, the experiences drawn from this pilot project have proven the need to pursue this behavioral approach. Future research should concentrate on subjecting the present approach to a strict experimental design involving randomly selected “poor risk” mines.

Jan 1, 1987

By Don Minard

Management support systems are extremely important to mining management to enable them to operate their company as a business. Management must give attention to the financial, maintenance, materials, and other reporting and control systems that are necessary to successfully operate a mining company. This subsection describes the management support systems that are critical to most mining companies. In this introductory review, the major objectives and functions of these management support systems will be introduced. The following topics will expand on the functions and key concepts as well as other considerations in each of these systems areas. Additionally, this introductory review will touch upon the unique environment that mining companies find themselves in from a management and personnel standpoint and the effect of this environment on management systems. Additionally, specific keys to successful systems installations and acceptance in the mining industry are discussed.

Jan 1, 1979

By P. M. Sandgren, H. Al-Dabbagh

Saudi Company for Precious Metals (SCPM) is jointly owned by the Saudi Arabian state organization Petromin (The General Petroleium & Mineral Organization) and Boliden of Sweden. The company operates the Sukhaybarat gold mine in the Saudi Arabian desert and produces some 80,000 ounces of gold per year by agitation and heap leaching. The discovery, development, and operation of this mine is a success story. After the first drill hole intercepted a gold mineralization in 1983, it took the partners only 8 years to delineate the ore reserve, locate water sources, prepare pre-and final feasibility studies, obtain permits, design, and construct the facilities. Sukhaybarat, which is an open pit mine, started off with a carbon-in-leach agitation plant only, but a heap leach facility was added in the beginning of 1995. Since start of operation in the middle of 1991, a total of 300,000 ounces of gold has been produced in the first four years of operation at a very competitive cost.

Jan 1, 1996

By G. F. Revey

All underground operations have limiting factors that influence overall profitability. Hoisting, hauling, available headings, labor, milling capacity and other factors limit how much material can be removed from an underground mine. Consequently, when mines use limited labor to handle the additional rock from overbreak and to perform extra ground support tasks, productive activity is replaced by nonproductive work. Mining economics are further penalized when overbreak causes dilution of ore grades. This paper reviews the organizational systems that mines have been using to create environments that foster the creation of successful overbreak-control programs. Actual case histories document the various quality-improvement techniques, worker incentives and practical project-management systems used by these mines. A brief review of controlled-blasting technology sources and overbreak-measurement tools is also included.

Jan 1, 1999

By C. Sachanidis

From the surface mines of Ptolemais basin 48 samples of Pliocene lignite were collected. The samples were analysed using Instrumental Neutron Activation Analysis (INNA) and Inductively Coupled Plasma (ICP) for determining the concentrations of 39 trace elements. The contents of sulphur and ash and the loss of ignition were also determined. The chemical affinity of these trace elements was estimated based on 40 correlation diagrams between the elements concentrations and the ash content of the collected lignite samples. According to the obtained results, 18 elements have inorganic affinity (Co, Cr, Cs, Hf, Sc, Th, La, Ce, Nd, Sm, Eu, Yb, Lu, ?n, Ba, ?, Sn, ?r) and 10 elements have inter-mediate affinity (As, U, ?r, Pb, Cu, Sb, Sr, S, Ni, V). The remaining 12 elements (Au, Ir, ??, Rb, Se, Ta, W, Tb, Ag, Cd, Bi, Be) exhibited concentrations below the detection limit. Thus, they were impossible to be classified in a specific affinity group. Based on the classification of these trace elements and sulphur in inorganic and intermediate affinity groups some useful conclusions are drawn regarding their behaviour during lignite combustion and lignite ash utilization and disposal processes.

Jan 1, 2006

By P. Berendsen

The tectonic and sedimentary environment of the Central North American Rift System (CNARS) provides all excellent setting for major mineral deposits. Major north-northeast-trending high-angle normal or reverse faults and northwest-trending transcurrent fault systems may exercise control over ore forming processes. Gabbro and basalt are the dominant igneous rock types. Carbonatite and kimberlite occur in Nebraska and Kansas. Concentrations of Cu. Ni, Co, Ti, Au. Ag and PG-minerals are known to occur in this setting. Arkosic sandstone, siltstone, shale, and minor carbonate units occur on top of the rift basalts and in flunking basins where they may reach thicknesses of 10 km (6 miles). The potential, for stratiform or unconformity-related metalliferous deposits must be considered. The rift as a whole remains, however, largely unexplored.

Jan 1, 1990

By O. Ofor

Finely-ground hematitic ore, too high in silica (quartz) to be commercially viable, was treated by emulsion flotation. A three-component emulsion mixture was used at temperatures ranging from ambient (22° C) to 30° C, 40° C, 49 °C, 59° C and 68° C. The optimal emulsion dosage and composition at ambient temperature were used to determine that dosage for higher-temperature flotation tests. The crushed ore (100%, -8 mesh) was repeatedly washed with tap water, and the filtrate's ionic content was analyzed. The separation efficiency values (a measure of the selective separation and concentration of hematite from gangue minerals) demonstrated temperature dependence, with marked increases at temperatures above ambient. The optimal separation efficiency occurred within the range from 30° C to 60° C. The improved separation efficiencies at temperatures exceeding ambient are explained by quartz depression. This depression is attributed to: • the precipitation of quartz-activating cations, principally calcium and magnesium, at increasing temperature; and • temperature's effect on the collector's solubility and attachment to the aqueous hematite surface.

Jan 1, 1993