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By David A. Campbell

There has been a long history of ironmaking on the North East coast of England centered around the River Tees. The industry developed here because of the availability of good coking coals to the North in Co. Durham, and the discovery in 1851 of ironstone in the nearby Cleveland Hills, South of the .River. Cleveland ironstone is relatively poor in quality, with an iron content not exceeding h% and high proportion of sulphur and phosphorous. The iron exists in chemical association with alumina and silica, and physical beneficiation processes involve a serious loss in iron unless the upgrading is limited, when the economics of the process become doubtful. Over the years, richer foreign ores have replaced the local ironstone, and the last operating mine was closed in 1964.

Jan 1, 1982

By R. W. Pugh, D. G. Bellow

"This paper will describe how cultivator shanks are made in one company and how the manufacturing was studied with a view to increasing product consistency and reducing manufacturing cost. The product: which is used extensively in the agriculture industry, was analyzed to determine which geometric parameters optimized its design and whether there was justification for the great variety of styles and shapes that are available in the market. Finally, an extensive series of field trials were undertaken which showed that it is advantageous to the manufacturer to be better aware of the loads and forces that his product is subjected to by another industry.IntroductionStelco maintains a Research Group for its Western Region operations headquartered in Edmonton, Alberta. Because of the small staff, a location that is isolated with respect to its Burlington, Ontario centre and a diverse set of processes and products, a university relationship has developed which may be different from that which would be developed at a larger integrated Steel Works. This paper outlines the type of cooperative studies carried out by Stelco Inc. in Edmonton and the University of Alberta. .To meet the research needs covering a wide variety of steelmaking processes and steel products produced in Edmonton would require more staff and equipment than the sales volume in the West justifies. The gap is filled by cooperation with university personnel. This cooperation has provided these benefits to Stelco Inc.:• access to specialized test equipment and a trained staff to operate it; and• assistance from experts in the areas of product testing and problem solving.Moreover, the close proximity of the university to the plant allows frequent meetings and ensures that practical solutions are developed and implemented. A good example of the ongoing university I industry relationship developed is the joint work on improving cultivator shanks."

Jan 1, 1982

The additional information that Clarke and Taylor (1982) provide about the important but poorly documented Ardlethan deposit is, of course, very welcome. However their contention that structural considerations, in conjunction with petrology, alter the interpretation of the mineralogical and geochemical data presented previously (Scott, 1981) is not accompanied by adequate supporting evidence. Indeed characteristics of the orebodies studied invalidate their arguments.Heterogeneity between matrix and fragments is not a problem in the South Cherry and Ardwest orebodies because most samples are comprised entirely of interlocking hydrothermal assemblages with a fabric and mineralogy that is uniform through both former breccia fragments and matrix. In hand specimen, the rock superficially resembles altered granite and, as indicated by Clarke and Taylor (1982), a brecciated texture is difficult to discern. In thin section, relict brecciated textures can be observed as localized changes in the grainsize or in the distribution of minerals that outline former breccia fragments (P. J. Eadington, 1982, personal communication).Because of the intense brecciation and comminution of rocks (fragments < 10 mm are usual) in the South Cherry and Ardwest breccia bodies, hydrothermal recrystallization was complete, resulting in homogenization of fragments and matrix. Furthermore, the amount of sample analysed (-100 g for drill core and 2-3 kg for hand specimens) is sufficiently large to be representative of both former breccia fragments and matrix. The Carpathia and Stackpool orebodies, with their abundance of sedimentary fragments, have alteration superimposed on a heterogeneous fabric, and were not studied. Thus the problems of differentiating between fragments and matrix (Clarke and Taylor, 1982) are irrelevant to the particular orebodies described in my paper.Within the alteration halo, which is several hundred metres wide (Paterson, 1976), the very uniformity of the alteration assemblages implies that subsequent, postmineralization brecciation is of only minor significance.Indeed tourmaline pipes in the Ardwest pit are less than several metres across (Clarke, 1979) and produce minimal alteration in the surrounding rocks. Therefore the interpretation of the mineralogical zonation is not compromised by the recognition of several periods of brecciation.

Jan 1, 1982

By Ray W. Amstutz

The shaft was drilled on US government land m the Piceance Creek basin and was funded by the US Bureau of Mines (USBM). It was drilled to 723 m to provide access to rich deposits of oil shale, nahcolite, and dawsonite for geotechnical test work and environmental mining research. Rotary drilling and dual-string, reverse-air, jet-assist circulation methods were used. Drilling required eight months. Site preparation, running, and cementing the casing required another four months. A 2.44-m ID steel welded casing, 508 mm thick was installed and 2.7 kt of cement were slurried and pumped into the annulus.

Jan 1, 1982

By Sehic OA

One aim of testwork and flowsheet development is to ultimately provide a reliable and flexible plant that is simple to operate and maintain. Testwork can indicate amenability of ores to CIP treatment and provide a basis for process design and economic appraisal. Batch cyanidation and CIP tests are often sufficient for small projects. Continuous multistage test rigs can be operated to simulate plant operation and to provide data for flowsheet optimisation. Operating requirements, gold recoveries and potential problem areas can be anticipated at an early stage with more confidence. Subsequent project development involving decisions on the basic flowsheet, equipment types and general plant arrangements are based on practical considerations and experience. Computer aided process modeling and economic appraisal can be useful in analysing various tradeoffs, firming up the flowsheet and equipment sizes, and in specifying operating targets for the future CIP plant. INTRODUCTION Carbon-in-pulp (CIP) technology which has developed rapidly since 1974 is now accepted as an economically and technically viable process for the efficient recovery of gold. This paper describes testwork and flowsheet development procedures used for CIP evaluation and design.

Jan 1, 1982

By A. Tewarson

Combustibility data are presented for 14 samples representing commonly used mine materials (treated and untreated wood, conveyor belt and brattice cloth). The combustibility data were obtained in the Factory Mutual Small-Scale Combustibility Apparatus (sample area -0.008 m ). The hazards associated with the mine materials were evaluated in terms of: 1) ignition/ surface flame spread using an ignition parameter (IP). A reasonable correlation was found between IP values and U.S. Bureau of Mines ratings for conveyor belts and brattice cloth and large-scale fire test data for treated and untreated timber sets; 2) generation of combustible vapors, using a vapor generation parameter (VP); 3) heat release using a heat generation parameter (HP). A reasonable correlation was found between HP values and the large-scale fire test data for treated and untreated timber sets; 4) generation of "smoke," toxic and corrosive products using a chemical compound generation parameter (CP); and 5) light obscuration by "smoke" using the light obscuration parameter (LP). All the wood treatments, except Fireguard, were found to be effective in reducing the fire hazard. The effectiveness of the treatment appears to be due to enhancement of carbon formation in the solid phase and enhancement of water formation in the vapor phase. Concepts are presented for establishing 1) the relationship between various parameters (IP, VP, HP, CP, and LP) and basic properties of materials, and 2) the usefulness of the parameters as criteria for the combustibility and fire hazard evaluations of the mine materials.

Jan 1, 1982

By Robert P. Apa

Energy Incorporated has prepared this final report presenting the results obtained from the program for extracting alumina from anthracite culm along with the recovery of energy. This work has been accomplished under the auspices of the U.S. Bureau of Mines with technical coordination through the bureau's Reno, Nevada facility. The objective of this program was to develop a process to recover alumina and energy from Northeastern Pennsylvania anthracite mining waste. The program included Identification of sufficient resources to support a commercial facility, identification of the operating parameters which maximize alumina and energy recovery, the development of a conceptual process design, preparation of material and energy balance(s), and the performance of a system economical analysis. The program was conducted in three major phases. In the first phase the program concentrated on selecting several anthracite culm banks capable of supporting a commercial alumina producing facility. The chosen banks were then sampled and analyzed leading to the selection of two banks which were chosen far testing. The Harry E. and Eckley culm banks were the ones selected. Material from these banks was tested in Energy Incorporated?s Idaho Falls, Idaho testing facility. Parametric testing was accomplished in an eight-inch-diameter fluidized bed test facility. The test program consisted of twelve separate tests. After critical operating parameters were determined, the second phase started: process development in EI's 18-inch fluidized bed test facility. Three material and energy balance tests were completed in this facility. Following these tests a 72-hour demonstration test was performed. The data acquired from these tests were used in the last phase: the process conceptual design and economic analysis. The design basis was a commercial scale facility capable of producing 500,000 tons of alumina per year for 15 years. Based on the test program, It is technically feasible to build and operate such a plant today. The facility would produce, along with the alumina, 81.5 MWe of electricity for outside consumption. A preliminary rate of return indicates that the plant is not feasible with today's economic conditions. An increase in the market price of either the alumina or the electricity is required to provide an attractive rate of return for the facility.

Jan 1, 1982

By Madgwick J. C

The monosaccharides glucose, galactose and arabinose, and the polyols glycerol and mannitol (0.1 Ufo WIV) supported pure and mixed culture heterotrophic bacterial manganese leaching of solid pyrolusite (MnO2, 2% W/V) to yield 14-38 mg/litre manganous ion in 3 days from a simple mineral salts media at 30°C. Supplementation of pure bacterial isolates growing on glucose with soluble intracellular photosynthate from freshwater algae (0.07 g/l carbohydrate) and marine algae (0.11 g/l) led to an improvement in Mn++ yields of 24 and 100 per cent respectively. Extracellular products of the freshwater algae (0.3 g/l carbohydrate) boosted recoveries by 57 per cent.

Jan 1, 1982

By Dave G. Osborne

With the growing exportation of coal from North America to the Pacific Rim countries and Europe, has come an increasing awareness of the need to determine economically optimized amounts of incombustibles (ash and moisture contents) for the shipped product. Despite the fact that demand bas caused a steady improvement in selling price, particularly for thermal coals, growing production and transportation costs have compelled producers to keep a sharp eye open for ways and means of minimizing the latter since this probably represents the greatest single potential for making savings. Consequently the Coal Industry has become acutely aware of the economic ramifications of eliminating moisture in particular, thereby producing further saving in the cost of transportation of product from the mine to the consumer. There is, however, a lower limit to which dewatering or drying can be taken and this relates to dustiness which is a function of the characteristics of the coal and the methods used for handling and storage during trans-shipment. Overdrying can lead to serious dust losses and difficulties in handling particularly if the coal contains a large proportion of fines. The ways and means for achieving this "happy medium" of optimization in moisture removal are seemingly undergoing gradual modification largely assisted by the following factors. a) Improvement in effectiveness of coal dewatering and drying equipment. b) Improvement in operational availability and utilization of the equipment. c) The development of surfactants, polymer flocculants and other agents which in many cases can be almost tailor made to suit specific applications.

Jan 1, 1982

By Phillip N. Yasnowsky

This Bureau of Mines report summarizes State severance taxes imposed on minerals and mineral fuels, provides a hypothetical example of how a State severance tax affects selected components of a firm's income statement, and uses the Bureau's Minerals Availability System (MAS) to estimate the effect of assumed changes in State severance tax rates on copper recovery cost at given levels of potential copper availability. A reduction of the rates to zero or a doubling of them results in changes in costs that are of the same order of magnitude as the cost of transporting copper to the United States from major foreign producing countries.

Jan 1, 1982

By R. S. Fukuhara, M. J. Allan

"Highmont, a wholly owned subsidiary of Teck Corporation, operates a 25,000 ton/day mine and concentrator located in the Highland Valley of British Columbia. Construction of the plant commenced in the spring of 1979, and production from one grinding line began in late December 1980. The second grinding line began production in March 1980.The ore body consists of two main zones, the east and west pits, containing 134 million tons of ore, averaging 0.26% Cu and 0.27% Mo. Mineralization consists mainly of chalcopyrite (2/3), bornite (1/3), and molybdenite.The concentrator design incorporates an A-B-C grinding circuit (auto mill ball mill - crusher), followed by bulk flotation, copper-moly separation and leaching for moly concentrates. The two grinding and bulk flotation circuits are parallel and independent. Concentrate storage is provided between bulk flotation and copper¬moly separation and also ahead of molybdenite leaching. The plant design has been previously described in some detail. (""THE HIGHMONT CONCENTRATOR"" by C. V. Sibbald, CIMM Bulletin, March 1981).This paper will outline some of the problems associated with the construction, startup and early operation phases of the concentrator. The objective is to help others avoid some of the potential pitfalls by outlining those areas where problems occurred, or where things went well. Criticism of design or equipment is not intended."

Jan 1, 1982

By Rolland L. Blake

Petrographic methods of examination were used by the Bureau of Mines on a suite of samples of ultramafic rock from Soapstone Ridge, Ga., located about 8 miles south-southeast of Atlanta. The samples were analyzed to determine (1) their potential for releasing regulatory particles upon crushing and grinding and (2) their concentration of fibrous particles that approach the dimensions of amphibole and serpentine asbestos minerals. Such particles might be generated during grading and excavation for housing and industrial development and could become a health concern. Light optical microscopy, scanning electron microscopy, and X-ray diffraction were the techniques used to examine the samples. Six of the twelve samples contained amphibole as a major mineral; in five, it was a moderate to minor mineral. One sample contained no amphiboles, and serpentine was not observed or identified by X-ray diffraction in any of the samples. In nine of the samples, the amphiboles exhibited a habit that was either prismatic or acicular, but not asbestiform. Two of the samples did contain asbestos, occurring as small veins or fracture fillings, which represented only a minor percentage of the total sample. Similar petrographic screening is recommended for examining any rock deposit or mine location to delineate hazardous and nonhazardous mineral areas.

Jan 1, 1982

By E. G. Baglin

As part of an effort to decrease U.S. dependence on imports of critical and strategic metals, the Bureau of Mines investigated three leaching methods for extracting the base metals and recovering platinum-group metals (PGM) from matte prepared from Stillwater Complex flotation concentrates. Because of a limited supply of natural material, synthetic matte of composition similar to matte prepared from natural concentrates was used to devise the extraction sequences. The validity of the sequences was verified with matte prepared from Stillwater concentrates. In two-stage matte leaching, first-stage H2S04 leaching extracted 99 pct of the nickel and iron from the matte but negligible amounts of copper and PGM. Second-stage oxidative leaching with Fe2(S04)3 or FeC13 solubilized more than 98 pct of the copper and no precious metals. Sequential leaching, in which acid and oxidizing lixiviants were added sequentially to the matte without an intervening filtration step, extracted 99 pct of the Fe, Ni, and Cu. A roasting-leaching technique, in which the residue from first-stage leaching was roasted between 360° and 500° C before a second leaching with H2S04, solubilized 98 pct of the copper. The three leaching methods yielded high-grade PGM residues containing more than 98 pct of the PGM in the matte.

Jan 1, 1982

Scientific and technical research is becoming an expensive business, and needs to be managed as well as directed. Regardless of whether it operates under public or private auspices, a research-and development organization should not tolerate inefficiency or irrelevance. Its true worth is ultimately decided by the impact it makes on its environment. Doing the right things is preferable to merely doing things in the right way. Clear definition and the setting of goals form the crux of the Management by Objectives (MBO) system. This system provides the research establishment with a profound sense of purpose and direction, which is essential for effective planning and control. Performance standards, in association with costs and manpower, value assessment, feedback, and improvement, tend to follow naturally once the principle of a results-oriented management system is adopted. MBO is a participative management system, leading to decentralization and self-control of the individual rather than imposed control. If wisely implemented with the necessary respect for creative work, it can enhance the job satisfaction of the research worker as well as the overall productivity ofthe research establishment.

Jan 1, 1982

By P. Diehl

The increasing public interest in a useful framework for an assessment and classification of mineral resources (1) is documented by the recently published international classification scheme of the United Nations (1979) and the revision of the classification system of USBM/USGS (2) (1980). Moreover, various classification systems are currently discussed by the mining industry. In spite of major improvements in respect of the concepts, definitions, and taxonomy of ore classification, it has been recognized that the recent practice to classify mineral resources does not create truly reproductible results, i.e. an assessment to the various categories which is free from personal bias or corporate interests. Following are geostatistical methods proposed for a standardization and quantification of various terms in ore classification. After critical review of present practices, we will establish a precise link between the classical terms such as "measured", "indicated", and "inferred" reserves and the geostatistical concept of estimation errors. Moreover, we will demonstrate, how the basic criteria of economic feasibility, geologic assurance and recovery can be taken into account by geostatistics. A specific algorithm will be proposed to block out and to classify reserves according to the degree of geologic assurance. . We will also show computerized methods which perform complete classification procedures, and will also exemplify them with typical case studies.

Jan 1, 1982

By Douglas A. Sloan

"Recently, a number of major mining companies seemed unable to find a president from within the industry, and were searching outside the industry. From this, one could conclude that managers within the industry are either not being prepared or are not preparing themselves for presidential responsibility. Opinions were sought from a number of senior executives, to attempt to define the skills a prospective president should acquire and what actions a company could take or that a prospective president could take to acquire these skills.This paper contains summaries of the opinions obtained, along with the author's comments. The paper also describes the actions some companies are taking and the actions that an aspiring president can take to prepare himself for corporate management.IntroductionA manager is promoted up the management ladder when the manager's superiors believe that he is capable of handling a more senior position. Normally, the manager acquires this credibility by outstanding performance in his current management post, whether it be in a junior management (supervisory) or in a vice-presidential capacity.In most instances, the skills required for promotion can be acquired in the current position or, at worst, the abilities exhibited in a candidate's current role will convince his superiors that the necessary expertise for the more senior position can be acquired on-the-job. This is particularly the case when the new skills are felt to be an extrapolation of the old skills.However, in the case of appointment to presidential rank, there appears to be a need for new expertise which often is not acquired in normal management progression or, at least, boards of directors of some mining companies seem to believe this to be the case. The objective of this paper is to attempt to define the new skills that should be acquired by a manager who aspires to be the president, and to describe what actions might be taken by him to acquire them."

Jan 1, 1982

By Stan Henning

The monthly summary of the climatological record for the demonstration mine is presented in Table 1. Tear normal temperatures occurred throughout the growing season. From May to October precipitation was more than normal except in June when it was 2.55 inches below normal. Corn and soybean plantings were delayed until June 2-7 because of wet field conditions. This is about one month later than normal for corn planting. Insect infestations were much less than those encountered in previous years. Cutworm activity was not noticed and alfalfa weevil infestation were small and patchy. Stalk rot in corn was a significant problem at harvest and resulted in much Milk lodging. The wet and generally overcast conditions of July, August and September were bend 10 beneficial al to certain plant disease organisms. For example, pumpkins planted in a small garden area at the demonstration mine did not ripen because of a powdery mildew resulting from overcast, wet conditions. Field operations and row crop plantings were greatly delayed by wet field conditions. It was difficult to plant by conventional tillage because the soil remained soft and sticky where the moldboard plow had been used. Plots in the no-tillage system could he planted before conventionally tilled plots could be traversed. Plant emergence and plant density at

Jan 1, 1982

By J. H. Crocket, J. Andy Fyon

"All gold deposits within the Tisdale Group are spatially associated with carbonate alteration zones; however, not all carbonate alteration zones are host to gold mineralization.Within the komatiitic and magnesium tholeiitic volcanic rocks at the base of the Tisdale Group, discordant and stratabound carbonate alteration zones occur throughout. The alteration zones consist of a ferroan dolomite - quartz inner assemblage which is enveloped by calcite-quartz and an outer chlorite-rich subzone. Factors which control the distribution of carbonate alteration include joint systems, flow contacts, synvolcanic faults and bulk composition of the host rock.Two environments of carbonate alteration can be recognized: 1) The subsea-floor alteration zones developed within the volcanic rock succession where hydrothermal fluids did not discharge directly onto the sea floor. Insignificant gold production has come from this alteration environment. 2) Seafloor zones, which represent points of hydrothermal fluid discharge into the hydrosphere, are spatially associated with felsic volcanic rock complexes and are host to syngenetic, auriferous cherty dolomite.Carbonatized, magnesium tholeiitic basalts, which are host to the auriferous, cherty dolomite, are enriched in antimony (>0.35 ppm), boron (>30 ppm), gold (>5 ppb) and lithium (> 35 ppm), but are depleted in copper ( < 70 ppm), with respect to carbonatized basalts not associated with gold. Orerelated, altered komatiitic flows can be screened using gold (>5 ppb), lead(> 10 ppm), arsenic(> 70 ppm) and antimony (>1 ppm).The habit, petrographic characteristics and certain geochemical characteristics of the altered volcanic rocks suggest that the hydrothermal fluid was of sea-water origin."

Jan 1, 1982

By A. L. Rutledge, R. S. Nichols

"Waste dump development at the Fording River Operation s in British Columbia began in 1971. In 1981, several unique as well as unplanned situations provided an opportunity to study water flows through waste dumps.The key to the drainage is naturally segregated rock sizes .created by end dumping from the crest of a pile. The largest size material accumulates at the toe. Flow rates along the base of the studied dumps varied from 2,800 to 13,500 m3/day or 0.032 to 0. 156 m3/s (1.2-5.5 cfs}. Sediment concentrations in the water ranged from 1 to 1,800 mg/I.This paper describes water flows through dumps of varied lithology and maturity. The results suggest that neither long-term water flow nor contained sediments in small streams are jeopardized when crossed by end-dumped fills.IntroductionThe Fording River Operations are located in southeastern British Columbia approximately 115 km north of the United State s and 10 km west of Alberta, within the medial range of the Rocky Mountains. All production is carried out at elevations ranging between 1,600 and 2,200 m above sea level.The property is within a continental climatic zone, with temperature extremes of - 40°C in January to +35°C in July. The average annual precipitation of 335 mm of rainfall and 390 cm of snowfall feeds the numerous seasonal, small drainage courses along the Fording River valley.Since start-up in 1971, 149 million bank cubic met res of waste from truck-shovel and dragline mining have been placed in numerous dumps or ""spoils"". The dumps were developed to the point that several unique situations could be studied. During the peak run-off period of May-June 1981, water flow studies were performed on dumps of varied lithology and maturity. This paper describes the results of the study."

Jan 1, 1982

By Terry W. Engelhart

"A computer-based approach to online supervisory control and operations management of bulk materials handling terminals". This paper describes an integrated computer facility supporting the functions and responsibilities of shift operations, scheduling, maintenance and management using real-time interactive techniques. The functions and responsibilities as related to coal export terminals are specifically addressed, although these functions would be equally applicable to other terminal configurations and other commodities. A discussion of the resulting benefits are presented: - throughput efficiency - long-term planning and scheduling, using simulation - operations monitoring and protection - demurrage/despatch optimization - preventative maintenance - operational productivity

Jan 1, 1982