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By P M. Hancock, Associates

Lacustrine sediments, hydrothermal explosion breccias and spring precipitates deposited 5200 - 1800 years BP as a result of geothermal activity at Lake Rotokaua, contain New Zealand's largest known sulphur reserves. Current drill indicated reserves are 2 600 000 tonnes of elemental sulphur, assuming a ten per cent (dry basis) cut-off, contained in some 17 000 000 tonnes of ore with an average grade of 214.0 per cent (dry basis) sulphur. Additional inferred ore containing 500 000 - 900 000 tonnes of sulphur has yet to be prospected by drilling. Geological factors will be important in exploitation of the deposit, particularly the extent and disposition of the orebody, sulphur grades and distribution, physical characteristics of the ore, permeability and stability of the overburden and the nature and extent of geothermal activity in the area. Trials to date indicate that Frasch mining and possibly opencutting are unlikely to be successful mining methods. Further mining feasibility studies will be required to ascertain the most likely mining system for the deposit.

Jan 1, 1984

By D. S. Yantek, C. B. Brown

The mining industry is beginning to implement lithiumion batteries (LIBs) to power mine utility vehicles (MUVs) and rubber-tired mantrips (RTMs). However, the ability of LIBs to withstand the harsh conditions for these applications has not been rigorously evaluated. Concerns with the use of LIBs in the mining environment will be discussed including the effects of mechanical shock and vibration, temperature extremes, and moisture exposure. This paper will discuss adverse effects of the mining environment on LIBs and provide an overview of scientific gaps associated with the environmental susceptibility of LIBs used on MUVs and RTMs.

Feb 1, 2024

By Cade Mweemba, Alex Mwanza, Jackson Sikamo

"The Zambian Copper mining industry as we know it today has its genesis from early in the 20th century in the 1920s. Consistent private sector-driven investment in the industry over a period of over 50 years in exploration, mine development and operation, development of minerals processing facilities, building of infrastructure for pyrometallurgical and hydrometallurgical processing, with attendant support facilities, including building of whole new towns, resulted in copper production going from zero to a peak of 769 000 tons of copper in 1969. At the same time, the industry created jobs to the extent that in 1972 the industry had over 62 000 direct jobs. The industry was nationalized in 1973 and remained in government hands for just over 24 years. During this period, the industry experienced a serious decline in production levels, reaching the lowest level at the dawn of the 21st century in the year 2000 when production was 250 000 tons. In terms of jobs, an average of just under 2000 jobs were lost every year in the 24-year period, reaching just over 22 000 direct jobs in 2000. Following the return of Zambian politics to pluralism and liberalized economic policies, the government decided to privatize the mining industry. The process started in 1996 and by the year 2000 all the mining assets had been privatized. The new investors embarked on serious investment to upgrade the assets and to develop greenfield mining projects. Fourteen years later and investments of over USD 12 billion, the industry production levels increased year- on-year to reach a peak of 763 000 tons in 2013 with direct jobs reaching 90 000. This paper discusses the impact of the mining industry in Zambia on the economy in areas such as employment, support to other industries, direct contribution to the national gross domestic product (GDP), foreign exchange earnings and social amenities. The paper also focuses on the performance of the mines during these periods vis-à-vis mineral availability, mineral grades and complexity, new technologies and human capital. This is looked at particularly in the light of current challenges the industry is facing and makes suggestions on how the industry can be nurtured to continue being a major driver for the Zambian economy and a major player in the international copper mining business."

Jan 1, 2015

The ore is very 'refractory. It consists essentially of arsenical pyrites, iron pyrites, zinc blende, galena, antimony as sulphide and probably, in combination with galena, as Jamesonite, magnesium, and aluminium silicates with quartz. Some of the oxidized ore, of which there is very little, has a very interesting composition. A specimen shown to me by the ,general.manager, Mr. F. B. Stephens, consisted of hydrated arseniate of iron, orpiment, pyromorphite, lead oxide, with magnesium silicates and quartz. The ore found in the mine with a composition similar to this specimen was valued for gold contents at 60 oz. per ton. This ore is found as a small leader, which runs parallel to the main ore body, at intervals cutting through it.The ore is conveyed from the mine to the reduction works by means of a double road tram line. The mine is situated about rooo feet above the plant on a hill. The grade is so great (about I in 2) that the loaded trucks coming down are able to pullthe empty ones up, thus obviating the necessity of motive power for haulage. All that is necessary is two large grooved pulleys, fixed at the summit of the hilI, and provided with a rope-break for steadying the speed of the trucks down the hilI.

Jan 1, 1903

By Mohamed Yusuff

Modern transportation systems are one of the most important achievements of our civilization and provide us with tools for broadening individual and social freedom of choice. The transportation system initiated today is handed dawn to the next generation, probably with little choice because of the enormous expenditure of monies involved, and influence their way of life as to where they should live and where they should work. The ever increasing antagonism between the citizens and the planners of the transportation systems necessitates a careful review of the entire planning process. The planning process can be broadly classified into: the goal formulation and decision making process; the plan development process; and the plan implementation process. THE GOAL FORMULATION AND DECISION MAKING PROCESS Goal formulation and decision making is one of the vital phases of the planning process and is primarily based upon social values. In measuring social values, the planner must employ an appropriate scale of measurement since in the absence of this yardstick, these values tend to became vague and abstract ideals. The need for major social programs and concerns (poverty, etc.) of the urban areas should be analyzed to determine the type of transportation system which would contribute to the solution.

Jan 1, 1974

By M. Heger

February 2, 1999 marks a milestone in earth-moving technology at the San Miguel Lignite Mine. It was on that date that The North American Coal Corporation (NAC) took delivery of three Leica Dozer 2000 GPS grade control systems for use on its bulldozers. The primary reason for the purchase of these grade control systems was to prove that GPS technology could safely and economically be utilized on heavy equipment to assist operators in defining grades. If these properties were successfully demonstrated, the ultimate vision of the project was to expand the system to a point were GPS would become the primary means of providing grade control information to the mine’s heavy equipment operators. Twenty nine months and more than $500,000 later this vision was realized when the final bulldozer operating at the San Miguel Lignite Mine was equipped with Dozer 2000. Presently North American Coal has a total of nine Dozer 2000 GPS grade control systems at San Miguel providing cut and fill information to operators 24 hours a day. These grade control systems have allowed the San Miguel operation to increase safety, reduce costs, improve operator attitude, and better ensure environmental compliance. This article discusses both the nature of these benefits and some of the issues that had to be dealt with along the way.

Jan 1, 2002

By Javier Leonardo Salazar Muñoz

Dado que en las operaciones mineras a tajo abierto, se utilizan volquetes de gran tonelaje, estos requieren de neumáticos acordes a su tamaño. Sin embargo, a mayor tamaño de llanta, la vida de los neumáticos se reduce. En ese sentido, el presente texto señala el proceso de gestión de los costos de los neumáticos en volquetes de gran tonelaje, donde el precio de los neumáticos se relacione con los costos de perforación y voladura, carguío, caminos y botaderos y costos generales. Asimismo, el costo de acarreo debe estar en función de la distancia de acarreo que recorren los volquetes.

Jul 31, 2003

By L. M. La Torre

El presente trabajo señala el procedimiento para la implementación de un modelo de flotación presentado en Limn@. Para ello, se adecúa el manejo de los datos de laboratorio dentro de un libro de Excel para así obtener los parámetros necesarios para su uso en el modelo de flotación y realizar la simulación de un circuito de flotación para un mineral con sulfuros de cobre, plomo, y zinc. De forma que se muestra cómo a través de pruebas de flotación batch en laboratorio es posible la evaluación del rendimiento de circuitos de flotación existentes y el diseño de plantas nuevas.

Sep 19, 2006

Experimental results are presented that test the hypothesis that the descaling behaviour of stainless steel slabs following reheating is controlled by interfacial roughening at the scale-steel interface. In this investigation, two stainless steels were considered: type 304 (austenitic, with 18% Cr and 8% Ni) and type 412 (ferritic/martensitic, with 11.6% Cr). It was found that the entanglement that arises at the scale-steel interface was in fact effective in maintaining scale-steel adhesion, under the mechanical descaling conditions used. In the case of type 304, descaling proceeded by fracture along chromite layers, which formed (by internal oxidation) on the austenite grain boundaries; for this steel, the extent of descaling depends most strongly on austenite grain structure, and not primarily on the conditions in the reheating furnace. In contrast, type 412 samples descaled only at the edge of the entangled zone, and showed a greater sensitivity to the reheating conditions; specifically, higher free oxygen in the reheating gas and longer reheating times were found to increase the residual scale thickness. Key words: stainless steel, reheating, scale, entanglement, descaling, fayalite, internal oxidation, grain structure, free oxygen.

Jan 1, 2003

By Arthur M. Hartstein

The Federal Bureau of Mines, under a contract with Ultrasystems, Inc., investigated the thermal oxidative degradation characteristics of conveyor belts used in underground mines. This included the determination of smoke evolution, glow characteristics, char yields, and the identification and quantification of all volatile decomposition products in the form of gram of specific product formed per gram of belt sample tested. In addition to these investigations, degradation studies were conducted on some pure ingredients used in conveyor-belt formulations. Three basic classes of belts were investigated: neoprene, polyvinyl chloride, and styrene-butadiene rubber compositions. The studies indicate that styrene-butadiene-based belts exhibit good flame resistance and are the least hazardous in regard to overall formation of toxic decomposition products. Under this program, thermogravimetric analysis was definitely established as a method of material differentiation.

Jan 1, 1976

Abrasivity and wear resistance are not intrinsic properties of materials, but rather parameters describing the interaction between the wear part and the material exerting the wearing action. Moreover, wear or, at least, that part of the wear which is due to the cumulative effect of minute scratches, is linked to the hardness disparity concept. Abrasivity, in this context, is a relative concept, pertaining to a metal-rock pair, rather than to a rock. Based on this assumption, a methodology has been developed and checked against actual cases, enabling description of the abrasiveness of arock or the abrasion resistance of a metal through the ratio of comparable quantitative indicators. The paper describes the methods and provides examples of applications to practical cases(namely: rock cutting, excavation by means of tunnel boring machines (TBMs), rock crushing, and hydro-mill cutting).

Jan 1, 2012

By John E. Rourke, O&apos

This report documents the process of site selection, instrument installation, data acquisition, and preliminary data analysis followed to characterize the physical response of overlying strata to longwall mining. A system of surface, subsurface and mine level instrumentation was installed at the Allen Mine in Weston, Colorado where the overburden varied in thickness from 600 to 900 feet. Survey monuments, automatic-recording strain-meters, multi-point rod extensometers, inclinometer-extensometers, stressmeters and tape extensometer convergence stations were installed to monitor displacements and stress changes. A preliminary analysis of the data acquired up until project termination has shown the system to be operative and strata response to be similar to that reported for other subsidence monitoring case histories. Recommendations for continued monitoring of the instrumentation systems are presented.

Jan 1, 1982

By Brown H. R, Wright E. A

The authors identify the workable coal seams, their distribution in relation to quality and economic occurrence and relate their analytical characteristics to industrial use. The development of established collieries is also discussed with regard to increased production demand.The authors also indicate the potential of the coal resources of the Southern District and postulate their ultimate development.INTRODUCTIONThe Southern Coalfield yields 30 per cent of the total production of bituminous coal in New South Wales. The economic potential of the coalfield was examined last by Harper (1915). Since that time additional knowledge has been gained by prospectors, mining companies and public authorities. Expansion in the steel industry and the building of power stations on the coalfields together with improvements in fuel technology, mining methops and road transport have resulted in production of coal from seams mice thoughtto have no economic value.DESCRIPTION OF THE COALFIELDFor the purpose of this paper the term Southern Coalfield includes also the South-Western Coalfield which together comprise the following Coal Districts:IllawarraDouglas ParkWollondilly-NattaiMoss Vale-Berrima (Hanlon, 1953).Geographically the coalfield is contained by the Illawarra Range in the east, the Shoalhaven River to the south, the Wollondilly River to the west, and in the north by a line...

Jan 1, 1958

By D. H. McCain

Through a unique partnership between the Colorado Mine Safety and Training Program (CMSTP), the Colorado Rock Products Association (CRPA) and the Higher Education and Advanced Technology (HEAT) Center, a video packed, dazzling CD-ROM training program was developed for new miners entering the aggregate industry. Why this product was developed, and why the aggregate industry, will be discussed along with the challenges faced throughout the project. Cooperation from every one involved including MSHA made this the product of which all other training materials in the mining industry will be measured against in the 21st Century. This product's versatility and wide application makes it a tool that is as critical to a mine's success as any earth moving machine. Developed with both state and federal grant moneys allows this product to be affordable to small operators and independent contractors. The quality of this two CD-ROM set rivals any commercially made CD-ROM training.

Jan 1, 2001

By A Giblett, T J. Napier-Munn

This paper presents the results of a test program evaluating the impact of sample mass on the precision of Stage 1 gravity recoverable gold (GRG) test results. Four ore types ranging from low to high GRG contents were the focus of testing. A method to predict the influence of sample mass on the confidence limits of the Stage 1 GRG test result is demonstrated. The results suggest that although small samples tend to overestimate Stage 1 GRG in samples with low gravity gold values due to higher mass pull to concentrate, such samples can give acceptable estimates of the Stage 1 GRG content with focussed sample treatment protocols.CITATION:Giblett, A and Napier-Munn, T J, 2015. Measuring the influence of sample size on the precision and accuracy of gravity gold estimation, in Proceedings MetPlant 2015, pp 367–372 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By C. O. Lee, Z. W. Bartlett, R. H. Feierabend

The Grand Isle sulfur mine is located in the Gulf of Mexico, approximately seven miles off the coast of Grand Isle, Jefferson Parish, La. The deposit is on acreage covered by oil, gas, and mineral leases originally issued in favor of Humble Oil & Refining Co. by the State of Louisiana which were continued, maintained, and redesignated by the U.S. Department of the Interior after passage of the Outer Continental Shelf Lands Act. The sulfur deposit was discovered in 1949 when Humble Oil & Refining Co. penetrated more than 200 ft of sulfur-bearing limestone in a zone between 1813 and 2075 ft below sea level. In 1954, Humble drilled ten more sulfur prospect holes, eight of which encountered sulfur ore. On September 19, 1956, Freeport Sulphur Co. acquired from Humble Oil & Refining Co, the sulfur rights underlying the tracts, and the actual design of the installation began the same month. The first structural contract was awarded in December 1957 and offshore erection began in June 1958. The initial phase of construction has been completed and production by the Frasch process commenced in April 1960. The estimated total cost of the project is $30 million, of which $8 million is the extra cost incurred by the necessity of offshore operations. More than $22 million was expended before production was started. GEOLOGY OF DEPOSIT Grand Isle is the third largest sulfur deposit in the U.S. The orebody embraces several hundred acres, but its outer limits are yet to be defined to the northeast, east, and south. Most Gulf Coast sulfur deposits occur in a caprock mantle of calcite (referred to as limestone), anhydrite, and occasionally gypsum, which covers the apex of an intrusive mass of salt. Commercial quantities of sulfur are usually confined to the calcite or limestone member. Most often such limestone is completely enclosed by dense anhydrite below and impervious sediments above, which effectively form a closed reservoir. The depth of the Grand Isle orebody ranges from 1800 ft to 2500 ft below sea level. Within the present boundary, the sulfur-bearing limestone varies in thickness from 220 ft to 425 ft, while the sulfur content varies an average of about 15 pct in the leanest hole to an average of about 30 pct in the richest. Rock containing less than 5 pct sulfur is not classed as ore, and holes assaying less than 20,-000 long tons per acre of sulfur in place are not considered commercial offshore. The sulfur enrich-

Jan 1, 1961

By D. R. Cook

This paper is a case history of an exploration venture for base metals, begun by the Rocky Mountain District of Bear Creek Mining Company in 1952 and completed in 1954. The project was based on the idea of W. S. Burbank, U. S. Geological Survey, that commercial deposits of base metals might occur in Paleozoic sediments beneath hydrothermally altered volcanic rocks in the Southern Bonanza mining district, Colorado. Here, an area of andesitic rocks, four square miles in extent, has been argillized, pyritized, chloritized and silicified. Geological, geophysical and geochemical studies were followed by the diamond drilling of three holes totalling 6,220 feet. Further alteration ang geochemical studies were made on the cores from these holes. A brief review of the alteration and geologic mapping, colored aerial photograph interpretation, geochemical soil and rock sampling, magnetic, gravity and radio-metric surveys are presented together with some conclusions regarding this work. This paper is a case history of an exploration venture for base metals, begun by the Rocky Mountain District of Bear Creek Mining Company in 1952 and completed in 1954. Important contributions were made to the project by personnel of the Rocky Mountain District and the Geophysics Division. Individual acknowledgements to these people are made at the end of the paper. BASIS FOR THE PROJECT The project was based on the idea of W. S. Burbank (1947, p. 444) that commercial deposits of base metals might occur in Paleozoic sediments beneath hydrothermally altered volcanic rocks in the Southern Bonanza mining district, Colorado. Paleozoic sedimentary rocks, including the favorable Leadville limestone, are exposed three miles south of the altered area, and reason exists to believe that they might underlie it within a reasonable depth. Alteration of pre-mineral volcanic rocks has been used successfully as a guide to concealed orebodies in the Main Tintic and East Tin tic mining districts, Utah (Bill-ingsley, 1933, p. 120-122; Lovering et al, 1949; Howd, 1957, p. 124-134; Cook, 1957, p. 73) and could be a useful guide here. GENERAL GEOLOGY AND STRUCTURE The Northern and Southern Bonanza mining districts are northwest of the San Luis Valley in southern Colorado, just within the northeastern edge of the San Juan volcanic province. The districts are1ocated on the southern extension of the Sawatch uplift, a prorninent northwest-trending structural high. The highly productive mining camp. of Leadville, Gilman and Aspen are on the northeastern and northwestern flanks of this uplift where Paleozoic limestones have

Jan 1, 1961

By H. William Zeller, T. E. Westpha1

The U.S. Bureau of Mimes evaluated the effects of two iron-based fuel additives on diesel particulate matter (DPM) emissions. The 5.6-L, six-cylinder test engine is typical of engines used in underground mines. One additive, ferrous picrate, did not measurably affect exhaust emissions. This report is mainly about a ferrocene-based additive that reduced DPM between 4 and 45 pct, depending on engine operating conditions. The report concludes that the DPM reductions were caused by the catalytic oxidation properties of a ferric oxide coating that developed inside the engine's combustion chamber. The ferric oxide coating also decreased gas-phase hydrocarbons and O, but it increased CO, and NO,. The increase in NO,, of about 12 pct, is considered the only adverse effect of the ferrocene-based fuel additive. The results suggest that the effectiveness of ferrocene was partially offset by increased sulfates because of the high-sulfur fuel used. Recommendations for continuing fuel additive research are presented.

Jan 1, 1992

By Edmond Chin

The land mass of the Asia and Pacific region comprises 11 million square miles or about 15% of the total Earth's land area. The bulk of the region is contained on the Asian continental land mass. Australia, the world's largest island or the world's smallest continent, alone is almost as large as the continental United States. The islands of New Zealand, New Guinea, Borneo, Sumatra, and Honshu are among the largest in the world. Collectively, they constitute a land area of 1.1 million square miles or an area about one-fourth the size of the United States. The countries in the Asia and Pacific region represent some of the most vibrant economies in the world. Japan is undisputed as one of the world's leaders in manufacturing and commerce. Hong Kong and Singapore are significant both as entrepôt and banking centers. The economies of Australia, the Republic of Korea, and Taiwan compare favorably to the level of the industrialized countries in western Europe. Indonesia, Malaysia, the Philippines, and Thailand have maintained strong economic growth during the past two decades. All these countries in the Asia and Pacific region collectively constitute a significant bloc as to raw materials production and consumption, as to manufacturing, and as to world trade.

Jan 1, 1992

By David Wilson

"El presente texto señala la importancia del uranio como combustible esencial en la industria de la energía atómica. Dado que Gran Bretaña tiene poco uranio en su subsuelo, se buscó un método que ayude a obtenerlo a través del mar. Posteriormente, los científicos descubrieron el uranio disperso en partículas pequeñas (3,34 millonésimas de gramo.) por cada litro de mar. Pero de los cálculos efectuados se deduce que el uranio contenido enlos mares de l mundo sobrepasa en total las 4.000.000.000 toneladas, Ante ello, se hizo pruebas como disolvente, hallándose contenido en las aguas pluviales de la zona de Nevada a través de la absorción de productos químicos a base de hierro y zinc. De forma que se utilizó materias inorgánicas como medio de arrancar el uranio de las sales marinas."

Jul 1, 1965