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Process Study on Some Ag-Cu-Pb-Zn Polymetallic Ore in South China

Sep 13, 2010

VOLUME II Volume II, in conjunction with Volume I, is a general guide to the selection of cost-effective methods of site data acquisition in all geologic environmental, and socio-political circumstances. The judgement of a generalist or trained specialist must be relied upon in the final analysis to design the optimum program for a specific site.

Jan 1, 1976

A forecast of energy demand in the non-commu- nist world to the year 1990 is presented with com- ments on the expected effectiveness of conservation efforts in achieving more efficient utilization of energy. A forecast of energy supply for the same period is presented showing the contribution of oil, gas, hydropower, coal, and nuclear fuels, with brief comments on the factors constraining the rate of growth of non-oil energy supplies. The role of `synthetic fuels', i.e. liquid or gaseous fuels produced from coal, oil shale, and tar sands, is reviewed with brief discussion of factors affecting the development of this industry. In somewhat greater details, the growth of demand for oil by geographic regions is analyzed. Particular attention is directed to the source of the oil supplies which will be required. The anticipated rate of discovery of new oil reserves is discussed with comments on lead times required in the development of new discoveries in hostile environments such as the Arctic and deep oceans. The continuing importance of oil supplied from countries which are members of the Organization of Petroleum Exporting Countries (OPEC) is illustrated. Oil will continue to be the marginal ('balancing') source of world energy supply throughout the forecast period and although it now appears that oil supplies will be sufficient to balance the energy equation during the 1980s, little flexi- bility will exist to cope with unexpected growth in demand or slippage in supply. Prudent energy re- source management will require major efforts to stimulate conservation and also to stimulate the rapid development of conventional and new forms of energy supplies and changes in energy consump- tion patterns to utilize the new supplies. Because of the long lead times and the massive capital require- ments involved, governmental policies are needed soon which will stimulate conservation and which will encourage businesses to move rapidly to assure the energy supplies the world will require in the 1990s.

Jan 1, 1978

By Firth B. A

The flotation of fine coal (minus 0.5 mm) often requires the addition of an insoluble hydrocarbon collector to apparently promote the adhesion of coal particles to air bubbles. A series of experiments was conducted using a radiotracer and narrow size fractions of clean coal to determine the effect of particle size distribution, collector addition rate, desliming of feed and emuIisification of collector on the distribution of collector between the different size fractions. The concentration of collector per gram of each size fraction was found to be approximately proportional to (average particle size)-2 except if the collector was emulsified prior to addition, the dependence altered to approximately (average particle size)-1. Mechanistic consequences are discussed.

Jan 1, 1982

By Dennis Ofiara

Several recent tunnel jobs have required special adaptations of hard rock TBMs. Some of the special job conditions are ?no blast? launch requirements, small shafts or launch pits, proximity to existing underground structures, and short tunnels where the TBM must be retrieved through the primary lining. This paper describes a few of these projects, and the machine adaptations that have made TBM excavation feasible.

Jan 1, 2008

By Xing Zhao, Michael A. Sutton, Vikrant Tiwari, Damien Bretall, Xiaomin Deng, William L. Fourney, Uli Leiste

The dynamic response of a thin aluminum plate subjected to both shallow and deeper buried blast loading was studied. Using a combination of high speed stereo-vision and three dimensional digital image correlation (3D-DIC), sequential stereo images acquired every 38.25µs during blast loading were analyzed to determine full-field deformations and plate motions (displacements, velocities and accelerations, effective surface strain and effective surface strain rate). Measurements indicate that the initial sheet deformation was highly localized for both shallow and deeper blast events, with extremely high velocity and acceleration values recorded during the earliest stages of impact loading. Full field strain and strain rate data indicate that well defined strain and strain rate “maxima” are created in the plate, with the potential of affecting the dynamic plate behavior as well as it local failure.

Jan 1, 2010

By R. W. Ottermann, N. D. L. Burger, A. J. von Wielligh, P. R. de Wet, J. L. Steyn

A low noise blast hole drilling system was developed to limit the risk of noise induced hearing impairment in mining operations. Noise induced hearing loss has been identified as a major occupational health risk in SA mines. The noise generated by pneumatic percussion drills is a major contributor to such noise induced hearing. This motivated the South African Safety in Mines Research Advisory Committee (SIMRAC) to commission the development of a low noise rock drill system. The system had to be designed, manufactured, tested and demonstrated in a simulated underground mining environment. The specification required noise levels below 90 dBA. Other important design considerations were ease of manual transport, setting up and operation. The primary design concept was to encapsulate a standard Seco S215 pneumatic rock drill in a composite material tube. The tube is pushed onto the rock face by a pneumatic cylinder and is sealed at the rock face by an elastic seal. The drill is pulled towards the rock face by a rope and pulley mechanism fitted inside the tube. This mechanism is powered by a second pneumatic cylinder. The actions of moving and setting the drill require two persons. However, the team can carry out the drilling function itself on several drills simultaneously because of the self-thrusting design. The drill is supported by two camlocks. The exhaust (air containing dust, water, rock shavings, oil and grease) is removed from the encapsulating tubes via exhaust tube to the end of the stope. In this way exhaust noise and air pollutants are disposed of away from personnel. Tests were conducted in a test stope. Noise levels of under 90 dBA were achieved, thereby attaining the primary design specification. This was achieved without materially compromising ease of handling. Penetration rate was somewhat improved compared to that of the standard drill, so that productivity could be maintained. Keywords: Drill, rock drill, quiet, noise, mine, underground.

Jan 1, 2003

By A Prinsloo, R Tewu

Automatic control of semi-autogenous grinding (SAG) mills has often been considered complex. Recent experiences at Century Zinc (worldÆs second largest open pit zinc mine) refute this. Together with operating knowledge and appropriate control techniques high quality control is achievable. In this application model-based, constraint, and multiple output control were employed. The control was implemented using standard blocks in the plant DCS. The resulting overall control strategy fulfils the operating objectives and controls the mill with minimal operator involvement over 95 per cent of the time. Previous campaigns using expert systems and complex DCS based control have lacked durability. Their fall into disuse is briefly discussed.

Jan 1, 2009

By J. R. Hoskins

This is the final report for Research Contract No. 00101300 (Min. 34) granted by the U.S. Bureau of Mines to the University of Idaho Mining Research Bureau. The research project is entitled "Development of Improved Ventilation Technology for Non-coal Mines and Other Underground Excavations.' The duration of the project was six calendar months, from 16 April to 16 October 1970. The budgeted cost was $34,867.00 of which $31,953.00 was to be furnished by the U.S. Bureau of Mines. The sequence of reporting that follows is to state the objectives as contracted, outline the program of investigation, highlight briefly the important technological factors peculiar to vein-type metal mine ventilation, and describe the normal methods of control. This is followed by the results achieved by the survey, and an itemization of the observed deficiencies in current technology. There follows a section dealing with the adopted Federal Regulations.

Jan 1, 1970

By M. R. Geer

Efforts to evaluate washery performance are nearly as old as the art of coal cleaning, and in former years there was no uniformity in either the methods used or the basic terminology employed. This situation, and the con- fusion it bred, prevailed until about the time of the First International Coal Preparation Conference in 1950, Largely because of the interest of the French coal research organization Cerchar, the subject of evaluating performance was given prime importance at this conference. As a result, there is now a much greater degree of uniformity in terminology and methods of expressing cleaning results. The International Standards Organization currently is working toward international standards of terminology and methods that should improve the situation even more. The various criteria that are used to evaluate the performance of coal- cleaning equipment fall into three categories, depending upon the extent to which they are dependent on the density composition of the raw coal; some are directly dependent, others are only indirectly dependent, and still others are substantially indenpendent.

Jan 1, 1962

By O. M. McRae

The Courtland-Gleeson area is in Cochise County about 15 miles east of Tombstone in southeastern Arizona. Rocks exposed in the area range in age from Pre-cambrian to Quaternary. The Precambrian is repre-sented by the Pinal schist. Paleozoic rocks include the Cambrian Bolsa quartzite and Abrigo limestone, Mississippian Escabrosa limestone, and the Permo-Carboniferous Naco Group limestones. Rocks believed to be of Triassic and/or Jurassic age include the Copper Belle monzonite porphyry, Turquoise granite, and Gleeson quartz monzonite. The Cretaceous is represented by andesitic volcanics and various sedimentary rocks. Tertiary rocks include the intrusive and extrusive Sugarloaf quartz latite porphyry and numerous dikes of various rock types. Quaternary conglomerates cover the northern and eastern part of the area. The geologic structure is extremely complex. All rocks as old as early Tertiary have been involved in either tilting, normal faulting, high angle reverse faulting, imbricate thrusting or folding and overfold-ing. Major deformation was initiated during the first half of the Tertiary. Northeast-southwest compres-sional forces caused thrust plates containing lower Paleozoic rocks to override Cretaceous rocks. Subsequently, two large slide blocks of lower Paleozoic rocks, acting under the influence of gravity, moved eastward. The imbricate structure and the gravity slide blocks were then broken by late Tertiary normal faults. INTRODUCTION The Courtland-Gleeson area, or Turquoise Mining District, has long been recognized as an area of extreme structural complexity. Gilluly 2 referred to the entire district as a "gigantic thrust breccia". In 1962, Bear Creek Mining Company completed a two year program of detailed geologic mapping supported by exploration drilling. The purpose of this paper is to present some of the results of this investigation and to provide a structural interpretation based on these results. The geologic map that accompanies this report is generalized and shows only the major and significant features. The area was initially mapped on aerial photographs on a scale of 1 in. equals approximately 500 ft. These data were transferred to a planimetric base using a vertical sketch master. LOCATION The Courtland-Gleeson area is in central Cochise County, about fifteen miles east of Tombstone, and about twenty-two miles northeast of Bisbee in southeastern Arizona (Fig. 1). The area is readily accessible over graded gravel roads from both Tombstone and Elfrida. GENERAL GEOLOGY Rocks exposed in the area range in age from Pre-cambrian to Quaternary. wilson3 and Gilluly2 have published very detailed descriptions of the principal rock units exposed in the area. Only a summary description is provided in Table I. A great number of previously unmapped narrow Tertiary dikes and small irregular masses of hornblende andesite porphyry, lamprophyre, and aplite intrude the Gleeson quartz monzonite in the western part of the map area. The scale of the map prohibits showing them. The aplite dikes are related to, and bear the same structural relationships as, the Sugarloaf quartz latite dikes found in this area. For that reason, and because both the hornblende andesite porphyry and the lamprophyre are post-mineral and post-thrusting, their omission from the map is not considered significant. Because so many of the contacts in the district are fault contacts, because bedding faults appear to be prevalent but are difficult to recognize and map, and because igneous intrusions are so common throughout the sedimentary section, it is virtually impossible to measure an exact total thickness of any of the sedimentary rock units. Nevertheless, neither the field mapping program nor the diamond drilling provided any basis for suspecting that the thicknesses of the sedimentary units are significantly greater or less than what might be inferred from surrounding districts.

Jan 1, 1967

By Ihsan Berk Tulu, Ted Klemetti, Deniz Tuncay, Cicek Sena, Zhao Haochen

"Analysis of Longwall Pillar Stability (ALPS) and Analysis of Retreat Mine Pillar Stability (ARMPS) treat the pillar as a passive structure that is designed to carry overburden dead-weight. This dead-weight is calculated by simple rules based on the geometry of the mining, such as “tributary area theory,” “pressure arch theory,” and “abutment angle theory.” Although the pressure arch loading approach indirectly accounts for the generally stiffer overburden response of narrow and deep panels, it does not include the effect of specific geology of the overburden in load calculations. The relationship between successful pillar layouts and overburden geology can be incorporated into the load calculation by using the Ground Response Curve (GRC) approach.This paper introduces the GRC modeling methodology to investigate the effect of overburden geology and excavation geometry on load transfer mechanisms using seven field measurement case studies from four U.S. mines. It was also shown that the modeling methodology used to derive GRC in this study approximates mining-induced stresses and deformations within 5% of the values measured in the field.INTRODUCTIONFrith and Reed (2017) stated that current state-of-the-art pillar design methods ignore the overburden mechanics and use estimated dead-weight of overburden to compute pillar sizes. In the United States and around the world, overburden loading is typically estimated by simple geometric rules, generally with the tributary area theory (TAT). The specific overburden mechanics, structural competence of the overburden strata, geology, in situ stresses, and overburden/pillar interactions are typically ignored. However, these important mechanical responses affect the stability of the mine pillars and openings; therefore, they also affect the safety of the mine workers.Research conducted by the National Institute for Occupational Safety and Health (NIOSH) after the Crandall Canyon mine disaster (Esterhuizen, Mark, and Murphy, 2010) showed that small panel width-to-depth ratios and stiff-strong overburden result in a reduction of the observed pillar loads, much smaller than the TAT estimate. In fact, as a response to the Crandall Canyon disaster, Mark (2010) implemented a pressure arch loading approach into the latest ARMPS program to recognize the inherently greater stability of narrow panels at depth. The pressure arch approach is a first logical step to introducing non-tributary area loading into the practical ARMPS program. Although the pressure arch loading indirectly accounts for the generally stiffer overburden response of narrow and deep panels, it does not include the effect of specific geology and mechanical response of overburden in the load calculations."

Jan 1, 2019

In several of the States of Australia, mining on private property has been seriously hampered by the fact that large areas of land have been alienated from the Crown before the discovery of gold or other minerals. In Western Australia this difficultyhas only occurred to a small extent, and has largely been overcome by an act entituled "An Act to Permit Mining on Private Property, No. XXIX., 'October, 28th, 1898." Under this act, the holder of a miner's right can apply for a gold mining lease on private land; such applicant may treat privately with the owner of such land as to the amount of compensation to be paid for surface ,damage, or the case may be brought before the Warden who will assess the damages. Private land used as a garden, orchard, or vineyard is exempt from lease, unless the applicant has authority from the owner, or such lease is limited to a greater depth than 100 feet from the lowest part of the surface.No lease shall be granted of any mines under any private land in any municipality unless either the applicant has authority from the owner, or such lease is limited to a greater depth than two hundred feet from the lowest part of the surface.The same regulation applies to leases of private land on which any hospital, asylum, or public building is situated or under or within one hundred and fifty yards laterally of any...

Jan 1, 1901

By J Law, S Jahanshahi, R Holmes

Iron ore is AustraliaÆs largest commodity export and is vitally important to AustraliaÆs current and future prosperity. However, while major expansions are currently in progress to satisfy demand, the industry is also undergoing major transformations. Reserves of traditional high-grade Brockman ores that have underpinned the Australian iron ore industry since its inception are slowly being depleted and alternative ore types such as Marra Mamba bedded iron deposits, Yandi and Pannawonica channel iron deposits and magnetite deposits are now being developed. However, the impurity levels in some of these alternative ores are higher and they require blending and/or upgrading as well as an advanced knowledge of their downstream processing characteristics to facilitate cost-effective utilisation by overseas customers. The research challenge is to use advanced techniques for mineral exploration, ore characterisation, mineral beneficiation, agglomeration and sustainable processing to identify and develop innovative and breakthrough options for locating, unlocking and enhancing the value of AustraliaÆs iron ore resources. Furthermore, to sustain the steel industry and hence secure the demand for iron ore, there is a growing need to enhance the environmental and business performance of the industry through reductions in wastes and emissions. Therefore, cost-effective breakthrough and enabling technologies that massively cut waste generation, CO2 emissions and water consumption are also being developed. These include the use of renewable fuels and reductants, waste heat recovery and conversion of by-product slag into a saleable substitute for Portland cement. A number of examples of recent developments in the above areas are provided in this paper.CITATION:Holmes, R, Jahanshahi, S and Law, J, 2013. Research and innovation for the iron ore to carbon steel value chain, in Proceedings Iron Ore 2013 , pp 3-6 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By C. Daniel Kealy

Dissolved and suspended solids are present in the free water of tailings ponds. This Bureau of Mines study was designed to identify the influences of the slime zone in preventing these solids from reaching the environment outside the tailings pond. The finite-element method was used to determine the rate of discharge of subsurface water from the Van Stone tailings pond in northern Washington. The slime zone was sampled and tested for the first time, and results were interpreted and incorporated into the mathematical model. Computer results were verified by installing and monitoring piezometers in the field and by a simulated (16- by 1/2- by 3 foot) laboratory model. Output from the numerical model defined critical seepage zones and revealed that proper pond design and maintenance can reduce pond seepage losses to a minimum. Minimization of seepage requires maintaining the pond water level over the slime zone. Sufficient physical, chemical, and limnological data were collected and analyzed to conclude that the only realistic reflection of synergistic effects is obtained by study of the indigenous biota in combination with quantitative chemical and physical data. Proper planning and management of the milling and waste disposal operations are the key to minimal pollution.

Jan 1, 1974

By B. M. Loftus

An investigation into the use of impinging stream (jet) reactors for the leaching of a free milling ore produced an increase in gold recovery by 10% while decreasing leaching time by up to 90%.Tests on refractory ores demonstrate no apparent improvement in recovery. However, leaching kinetics are dramatically increased when these ores are subjected to jet reaction prior to agitation.

Jan 1, 1997

By W. V. Mutler

Present day capital costs are analysed for a 2 000 metric tonne per day (MTPD) pyrite burning plant and compared with a sulphur burning plant of the same capacity. Power, raw material and steam production rates are then compared for the two facility types. A sensitivity analysis is conducted to highlight the impact changing sulphur, pyrite, capital and operating costs have on the relative economics of these feeds. Technological improvement effects on capital cost and energy recovery are also discussed. Besides the steam produced from the burning of pure sulphur or pyrite, plants using an advanced form of heat recovery can produce up to 10 bar steam using heat from acid formation. The quantity depends on the overall water balance which is influenced by such factors as gas strength and product acid concentration. Modern materials and innovative process design also improve the ability to increase the high pressure steam from the roaster boiler in pyrite plants above the traditional 1.25 kg of superheated steam per kg of acid produced.

Jan 1, 2009

By G. Coetzer

During galena flotation of Rosh Pinah milled material, metal ions and salts contents of various water resources (deionized, simulated circulated, lead concentrate thickener, lead tailing thickener and borehole) influenced mineral recoveries, upgrade ratios, selectivities, froth stability and flotation kinetics. The various water resources employed during galena flotation caused activation, depression or selectivity effects on minerals due to the presence of different ions in solution. Metal ions in these water resources were adsorbed by the ore, whilst ions associated with gangue minerals (dolomite and quartz) were released into the flotation pulp. Lead concentrate thickener water caused depression of sphalerite and pyrite, increased fast floating fractions for silver, copper minerals, sphalerite and quartz (unwanted), and improved slow floating rate selectivity against pyrite and sphalerite. Lead tailing thickener water enhanced sphalerite recovery during galena flotation (unwanted), and increased fast floating fractions of pyrite. Western borehole water did not affect galena recovery, but sphalerite and pyrite recoveries were unacceptably too high. Ions from copper, lead, and zinc salts tended to release high amounts of ions, such as calcium, magnesium, silicon, and manganese from gangue minerals (dolomite and quartz) during milling. During galena flotation, lead ions depressed sphalerite, pyrite and dolomite at a lead concentration of 400 ppm, but sphalerite was activated at a concentration of 800 ppm. Sphalerite was activated with copper ions (89% recovery, 2.09 upgrade ratio) and depressed with zinc ions (maximum recovery of 25%). This corresponds with findings in previous investigations. Dolomite and quartz were slightly activated with zinc ions. No evidence was found that lead and copper ions activated any gangue minerals during galena flotation. Keywords: galena, water resources, metal ions, activation, depression, selectivity.

Jan 1, 2003

ABSTRACTMechanised cut and fill stoping in the Racecourse orebodies between II and 9 levels was started in 1964.Five stopes are in progress over the two level interval, extracting the full strike length (600-2,000 ft) of each orebody without transverse pillars.Each stope is served by a central 10 ft by 12 ft service intake ventilation raise and an 8 ft by 8 ft return air raise at each end of the stope. Each stope is divided into two sections for drilling. firing. mucking, and fillingto maintain steady production. All equipment is kept in the stope for one level lift stoping. Gardner-Denver 2 boom jumbos are used for uphole drilling and Wagner ST 5 Scooptrams for loading and transport to ore passes located in the footwall of the orebody. A Wagner PTIO is used for materials handling and scaling of the stope backs.Mill tailings, after one stage of cycloning are used to fill the stope, one section at a time. About 80 per cent of the water is removed by decantation while the remainder percolates through hessian-covered pipes and boxes.The ore is passed to 11 level where it is hauled by the 3 ft 6 in. gauge train to the tipple at the shaft area. The ore is crushed underground before hoisting to the surface.A performance of about 100 ton/manshift is achieved by the drilling, blasting, and mucking crews in the stopes.

Jan 1, 1968

By P Christen, D R. Ashley, G R. Power

The Ernest Henry Mine is currently a copper-gold open pit operation situated in north-west Queensland, Australia. It is owned and operated by Xstrata Copper with a current throughput of 11 million tonnes per annum; however, open pit operations are scheduled to cease in late 2011. The deposit dips at approximately 45¦ and extends for at least another 400 vertical metres below the final 530 m deep pit design. Resource drilling from 2002 until mid 2008 has enabled an Indicated Mineral Resource to be established to 1000 m below surface. Scoping and prefeasibility studies (PFS) have been completed toward determining if this resource is suitable for underground mining and a feasibility study is currently progressing with a sublevel caving (SLC) concept. This paper briefly describes the process by which the SLC method was selected, conclusions regarding the non-selected methods, and then discusses the optimisation process used to derive the mining plan. The key optimisation parameters include the production drive spacing, level spacing, draw strategy, cut-off grade and production rate. Key risks will then be assessed and economic sensitivities studied. Final sensitivities will use Monte Carlo simulations to improve the transparency of the projectÆs risk profile. The feasibility study (FS) began in March 2008 and this paper describes the main optimisation steps at the time of writing and outlines the plan for study completion through to March 2009.

Jan 1, 2009