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By D. J. McCracken

During 1995, the estimated consumption of lithium minerals in the western world was 139 kt (153,000 st).This amounted to 18 kt (20,000 st) of lithium carbonate equivalent (LCE). Overall tonnage demand for lithium minerals increased by 10.8 kt (11,900 st) during 1995from 1994. From 1992 to 1995, overall tonnage demand has increased 62%, from 85.5 to 139 kt (94,240 st). There are four major producers of lithium minerals. Gwalia Consolidated in Western Australia is the largest producer of spodumene. It supplies high-grade spodumene concentrate, fine-spodumene concentrate, glass-grade spodumene and chemical-grade spodumene.Tantalum Mining (Tanco) of Manitoba, Canada, produces high-grade spodumene concentrate, fine-spodumene, concentrate and montebrasite. Bikita Minerals in Zimbabwe is the largest manufacturer of petalite. It supplies high-grade and container-glass petalite.

Jan 1, 1996

By D. Bradbury

Sufco coal mine, a subsidiary of Arch Western Bituminous Group, recently purchased a reverse osmosis (RO) system. The systems intent was to remove impurities in the water being mixed with the hydraulic oil to maintain the viability of critical longwall hydraulic systems and to prevent degradation. This project not only ensured hydraulic components from corrosion, but also revealed a cost savings by reducing the percentage of hydraulic oil mixed with the RO water. SUFCO WATER TREATMENT HISTORY Sufco coal mine has been in operation for approximately 70 years. Old works extend up to 15 miles one way, not including adjacent mined out longwall panels. Due to the geologic conditions and strata, water treatment has been as simple as putting water in at a high point of a mined out area and recovering it at a low point to discharge. Doing this reduces the total suspended solids (TSS) to less than 25 parts per million (ppm) and the total dissolved solids (TDS) less than 1,200 ppm which complies with Sufco?s water discharge permit. Even though the requirements for the permit were met, the water is still corrosive in nature. A portion of this water is piped back into the fireline (makeup) water system. It is then boosted to pressures of up to 500 psi to support mining sections, belt systems, equipment, fire fighting systems and the longwall.

Jan 1, 2011

By Gordon Miner

GENERAL DESCRIPTION At the Star mine, Hecla Mining Co., located in Burke, Shoshone County, ID, the mining method is horizontal slicing (timbered or untimbered) cut-and-fill using hydraulic sand backfill. Back stoping as well as breast stoping is used; see Fig. 1. The annual produc¬tion from all cut-and-fill mining is 259 816 t (286,400 st). The average depth ranges from 366 to 2408 m (1200 to 7900 ft). A majority of the tonnage comes from an average depth of 2240 m (7350 ft). Average travel time to the stope is 1 hr. GENERAL ORE BODY REQUIREMENTS AND LIMITATIONS Size and Ground Conditions The ore body is 610 to 1219 m (2000 to 4000 ft) along the strike and 2408 m (7900 ft) on the dip, with an average vein width of 2.6 m (8.5 ft). The dip is essentially vertical. The ore body is heavily sheared and broken on the main fault structures; it is more competent on the wall veins but everywhere subject to rock bursting at depth. The hanging and footwalls are strongly fractured on the main fault structures, again more competent but still fractured on the wall veins. All host rock is Revett quartzite. Value and Production Requirements The ore value is $56 per ton. Production require¬ments are 1089 t/ d (1200 stpd), five days per week. Why Cut-and-Fill? The slusher extraction method is the most satisfac¬tory and practical for narrow vertical veins with sheared walls. The method must be quite selective to be com¬mercial. The veins are too narrow for rubber-tired ex¬traction and the grade is not high enough to make resuing practical. DETAILED DESCRIPTION Development Access to the main shaft is by the 3.2-km (2-mile) main haulage tunnel. The level intervals in the vertical timbered shafts are 61 m (200 ft). Vein development is by crosscut and laterals located 30.5 m (100 ft) into the vein wall. Vein crosscuts are on ±61 m (200 ft) centers. Access to the vein is by raises carried up with the stope. The raises are equipped with four wood¬cribbed chutes (two orepasses reinforced with angle irons, one manway, and one timber slide, Figs. 2-6). The initial cut is located 6.7 m (22 ft) above the main level (Fig. 1). Stoping Cycle Detail Sampling: Grab samples are taken from the mine cars. Channel sampling of the faces and backs is done when necessary. Drilling: For stope drilling, Ingersoll-Rand 300M percussion drills are used, with Ingersoll-Rand 300M and Gardner-Denver RB83M stopers, used for back stoping. Breasting down is done with Gardner-Denver S83FM jacklegs. The back stoping rounds are 0.9 to 1.8 m (3 to 6 ft) and the breast stoping rounds 1.5 to 3m (5 to 10 ft). Blasting: For stope blasting DuPont Tovex 100 watergel with fuses and igniter cord is used primarily. Approximately 60% of the blasting is done with am¬monium nitrate-fuel oil (ANFO). For development headings and shaft sinking, DuPont Drivex watergel with Ensign Bickford Nonel Primadet primers is is used. Mucking: Broken ore is removed entirely by slusher in the stopes. These are mostly 3.7-7.5-kW (5-10-hp) Ingersoll-Rand air-powered or 7.5-37.3-kW (10-50-hp) Ingersoll-Rand electric-powered. In the horizontal de¬velopment headings Eimco 12B and 21 and Atlas Copco LM-56 overshot mucking machines and a 0.76 (1 cu yd) hydroelectric Wagner HST-1 LHD (load-haul-dump) unit are used. Rockway for Extraction: The cribbed chutes (Fig. 7) are nearly vertical and hexagonal in shape and are made of spaced 152 x 203-mm (6 x 8-in.) timber, reinforced with varying weights and sizes of angle iron, depending on wear requirements. Rectangular cribbed chutes are used where ground pressure is not a problem. Cribbing is added in 2.4 or 3-m (8 or 10-ft) extensions accord¬ing to the floor height (whether timbered or untimbered). See Figs. 8 and 9. Backfilling: Backfilling is done with hydraulic sand consisting of classified mill tailings at 65% solids. The fill contains approximately 20% 325-mesh fines. The tailings are pumped 3353 m (11,000 ft) at 50-55% solids 22.7 dry t/h (25 dry stph) with a duplex piston pump. Cycloning increases the tailings density to 65% solids. Fill storage is in a 998-dry-t (1100 dry st) agi

Jan 1, 1982

By A. K. Sinha

Modern mine ventilation systems have grown rapidly in recent years both in tern of its complexities as well as its value for human health and safety. Although computer models are now available to help the design and operation of mine ventilation systems, considerable differences often exist between the computer based predictions and practical results. Research conducted to compare computer result with practical measurements made in ventilation circuits simulated in a physical model seems to confirm such differences. It is concluded that although a mine ventilation computer model is a very powerful tool, it can be utilized to its full potential only after more reliable input data are developed.

Jan 1, 1985

By Andrew Stafford, Kate Willa Brown Requist, Eric Lutz, Simon Lotero Lopez, Moe Momayez, Jeffrey Gordon

This formal literature review identifies strengths and shortcomings of current literature related to mine rescue, self-rescue, and self-escape technology. Key concepts and factors that influence the decision making behind mine rescue and self-escape were identified. Historically, underground mining has been one of the most dangerous occupations due to the harsh nature of working environments. During the latter half of the twentieth century, and into the twenty-first century, mining fatalities have declined, yet large-scale mine emergencies persist. The emergence of new technologies, in combination with evidencebased mine emergency research, is resulting in new training methods, monitoring systems, and self-escape approaches being tried in operating mines. This review identifies areas in which substantial research is being conducted, such as the use of virtual reality and game-based training and areas that warrant further development such as the measurement and information gathering capabilities of unmanned ground and aerial vehicles, as well as emergency management and incident command systems. This paper summarizes the current underground mine rescue and self-escape landscape in the USA, including the breadth and depth of mine rescue and self-escape training and practices as evident in the literature.

Nov 2, 2023

By T. Karalis

Perlite is a generic term for naturally occurring siliceous rock. It is a form of natural volcanic glass the main constituent of which is amorphous silica (70-76%). Perlite, when heated rapidly to its softening temperature range, expands from four to twenty times its original volume, due to the presence of 2-6% ?combined? water, in a manner similar to popcorn as the H2O molecules vaporize and create countless tiny bubbles, which account for its exceptional physical properties: light weight (30-150 kg/m3), low thermal conductivity, cellular structure, in general. These properties make perlite adaptable for numerous end-uses, which can be distinguished into 2 categories: Expanded perlite applications in: a) Construction Materials market (e.g. Acoustical Tiles, light-weight insulating Mortars, self-levelling Concrete), b) Agriculture (e.g. Hydroponics), c) Food and Chemical industry (e.g. Filtration Media, Filler, etc.), d) Insulation and Heat resistance technology (e.g. Cryogenic vessels, Refractory Bricks, etc.). Unexpanded Graded perlite applications in: a) Phosphoric Fertilizers industry (additive in H3PO4 production), b) Foundry technology (slag-aid, insulating and heat resistance agent).

Jan 1, 2006

By J. G. Groppo, A. E. Bland, B. K. Parekh, W. F. Stotts

Many coal preparation plants discard fine coal (generally minus 100 mesh) because it is difficult to beneficiate economically. At the Kentucky Energy Cabinet Laboratory (KECL), the waste streams from several Kentucky preparation plants were evaluated for cleaning with counter-current column flotation. A series of performance evaluations were conducted using a 0.05 m (2 in.) internal diameter (I.D.) 7.9 m (26 ft.) high laboratory column. The objectives of these tests were to assess the performance in terms of recovery and percent ash in clean coal and to optimize the operating parameters relative to combustible recovery and grade. Refuse streams containing 30-50 percent ash were upgraded to 2-8 percent ash with Btu recoveries of nearly 90 percent. A pilot scale column flotation cell was installed at the Bell County Coal preparation plant. This pilot plant utilized a 5.79 m (19 ft.) high and 0.15 m (6 in.) I.D. column to verify the performance data of the 0.05 m (2 in.) I.D. column for two different waste streams. Performance evaluation and pilot plant testing results related to scale-up are discussed.

Jan 1, 1988

By W. K. Katoto

The Tailings Leach Plant (TLP) of the Zambia Consolidated Copper Mines Ltd at Nchanga was commissioned in 1974 as the world's first largest successfully operated agitation leach SX-EW plant for copper production. The design, development and operation of the plant soon after commissioning termed as TLP stage II has been described by Holmes et al (1). In the initial phase the plant was designed to treat approximately 25,000 tonnes per day of current flotation tailings from the Nchanga Concentrator operations, and had a design capacity to produce 75,000 tonnes per annum of copper. Further expansion took place in 1986, and TLP stage III was successfully commissioned to treat an additional 20,000 -25,000 tonnes per day of large reserves (over 135m tonnes) of reclaimed tailings stockpiled since the early 1930's in four paddock type tailings dams (T01 to T04). The salient feature of TLP stage III expansion described by S K Mwenechanya et al (2 -3) was the installation of the world's largest Horizontal Belt Filter Plant with 26 filters each of 80 m2 filtration area.

Jan 1, 1996

By John Drew Ridge

Tables showing world trade in metallic mineral raw materials during the years 1953 through 1957 have been prepared for the following twenty-one commodities: alumina, aluminum, bauxite, chromite, copper concentrates, partly refined and fully refined copper metal, iron ore, pig iron, iron and steel (simple shapes), lead concentrates, lead metal, manganese ore, mercury metal, nickel ore, concentrates, and matte, nickel metal, raw pyrites, sintered pyrites, tin concentrates, tin metal, zinc concentrates, and zinc metal. In each instance, the amounts given by the importing country were used except when statistics from the importing nation were lacking, incomplete, or misleading. To show the considerable divergence between importing and exporting country totals for the same years, the complete mercury table is given and, in parallel columns, shows the comparable tonnages of importers and exporters. Tables for the other twenty commodities are presented in summary form. The data of the concentrate tables are used with those of the corresponding metals as a basis for a discussion of trade in concentrates versus trade in metals. The data of all twenty-one tables provide the basis for testing the thirteen rules governing international trade in metal raw materials which I first published in Mining Engineering for July 1955. Because the 1953 through 1957 data are far more complete and considerably more extensive than those on which the 1955 rules were based, it was found possible to deduce five additional rules and to modify three of the original thirteen appreciably. The full text of the eighteen rules is given.

Jan 1, 1960

By C. Dirscherl

"Declining ore grade, leading to increased material transport and plant throughput requirements, is one of the major challenges in the current mining environment. This is accompanied by rising energy and labor costs, decreasing plant productivity and the requirement for highest plant availability. Siemens’ answer is the latest gearless drive technology for grinding and conveying. Gearless drive solutions are surpassing the mechanical limits of conventional drive systems serving to utilize the principle of economies of scale. By elimination of various components of the drive train, the maintenance activities and spare parts inventories are reduced. The advantages are culminating in the incomparable availability of the Siemens’ gearless drive technology of 99.46 to 99.71 percent — as confirmed by real operational data from the Antapaccay Mine in Peru. It was the first plant worldwide to use gearless drives for both applications.The gearless principleThe principal idea behind a gearless drive system is to reduce the number of components and diversity of parts, especially those components that are at the edge of current manufacturing or power limits are eliminated. The used equipment provides the possibility to scale up and increase the power transmitted to the driven machine. This finally results in a possible increase of throughput respectively transported or processed material.In order to apply this principle of simplification, the components of a conventional drive system are examined. They consist of:• Driven equipment (mill, conveyor, slurry pump).• Components altering the rated speed (gearboxes, girth gear/pinion).• The electric motor.• Starting devices for the motor (VSD, CCV, LRS, clutch), which are necessary because a direct across-the-line start of high power motors with load would result in a significant drop in the line supply voltage.• Alternatively a variable speed drive (VSD) or cycloconverter (CCV) to utilize the possibility of speed variation during operation.• The electrical supply system (cables, switchgear, transformers, protection equipment)."

Jan 1, 2015

By Yi Yang, CHENGLONG XU, HAORAN LI, YALI FENG, JINRONG JU

This study presents a method for recovering valuable metals and synthesizing anhydrite from steel slag using sulfuric acid leaching and solvent extraction. The process achieved high leaching efficiencies for V, Ti, Fe, and Mg, and produced anhydrite with 93.09% purity. The leachate was further processed to separate and recover V, Ti, Fe, and Mg using selective stripping and precipitation methods, offering a sustainable approach to steel slag utilization.

Jan 22, 2022

By R. Todd Swinderman

"Higher production demands across all bulk handling segments require increased efficiency at the lowest cost of operation, in the safest and most effective manner possible. As conveyor systems become wider, faster and longer, more energy output and more controlled throughput will be needed. Add an increasingly stringent regulatory environment and cost-conscious plant managers must closely review which new equipment and design options align with their long-term goals for the best return on investment (ROI).There are primarily two separate market segments using conveyor belts. One is in process industries such as food, chemicals, paper and powders. Handled in relatively low volumes, the bulk materials that enter these processes are generally of a consistent size and quality. The other market includes mining, coal handling and cement, where the bulk material’s quality and size vary, and the volumes are typically much greater. While both segments face similar issues with safety and environmental control, the properties of the materials handled and the volumes transferred suggest different approaches, with one thing in common: increased belt speeds requiring modern equipment upgrades.Safety at higher belt speedsWith companies recognizing that safety does indeed pay, safety is likely to become a new source of cost reduction. The percentage of mines and processing facilities with a robust safety culture are likely to increase over the next 30 years to the point where it is the norm, not the exception. In most cases, with only a marginal adjustment to the belt speed, operators quickly discover unanticipated problems in existing equipment and workplace safety. These problems are commonly indicated by the larger volume of spillage, increased dust emissions, belt misalignment and more frequent equipment wear or failures."

Jan 11, 2018

By Mostafa Benzaazoua, Bruno Bussière, Mukendi Kongolo

The desulphurization process has been proposed over the last few years for acid mine drainage control at certain mines, which generate low to medium grade sulphidic tailings (-3 to +25 wt% S). The environmental sulphur recovery, which means the sulphur to be floated to produce a non-acid generating final tailings, depends mainly on the intrinsic neutralizing potential of the tailings. However, in some cases the sulphur cleaning is complicated by other parameters which affect the flotation probability of the sulphide particles. In this study, a number of tests were conducted with a Hallimond tube and Denver Cell on both pure mineral and mine tailings. To develop a better understanding of the mechanisms of non-selective sulphide flotation, three types of approach were investigated in this work: (i) pure pyrite at progressive milling degrees, (ii) artificial mix of pyrite and quartz at different calibrated granulometry and (iii) same composition tailings with 26 % wt sulphur at progressive milling degrees. The effect of the granulometry on the sulphide flotation was demonstrated both. The results allow us to define a granulometry model, which can then be considered in the whole desulphurization modeling.

Jan 1, 2000

By Jorgen Elbrond

The capacity calculation of complex transportation systems involving variable activity times such as encountered in the mining industry are often worked out by means of simulation, which reconstructs waiting times and cycle times. The queuing theory, which mathematically calculates waiting times, has been used mainly to describe the, phenomena. This is due partly to the difficulties encountered in modelling complex systems and partly to the difficulty of reconciling the required time distribution laws with the real phenomena by means of the queuing theory. It is, however, obvious that formulas for capacity calculations would be preferable to simulation procedures because of their higher calculation speed, shorter and more flexible programs and shorter programming work. The calculation procedure presented in this paper is composed of some rather simple models, which are based on the queuing theory, and on some probabilistic and some deterministic considerations. The models are supported by observations, and to some extent by simulations. It has been attempted to find all the components of the cycle time and to include them in a comprehensive model. It is the intention to demonstrate that even quite complex mine transportation systems can be treated by means of the queuing theory with the advantages mentionned above and, without sacrificing the precision of the estimates. The speed of calculation of a wide range of parameter combinations is such that the procedure can be used extensively by a project engineer in the search for optimal modifications of the entire transportation system.

Jan 1, 1979

By O. Ofor

Coal fines of less than 0.5 mm particle size, discarded as too fine for gravity separation, were subjected to flotation tests at varying pH and temperatures using modified dosages of kerosene as oil phase and methylisobutylketone (MIBK) as frother. Optimal coal recovery of over 74% was obtained using 200 kg kerosene and 4 kg MIBK per ton of coal fines at a pH of 9.7 and an ambient temperature of 26° C. The coal concentrate obtained under these optimal recovery conditions assayed 9.10% ash, 0.35% sulfur and 0.011% phosphorus, representing reductions in the ash, sulfur and phosphorus contents of approximately 75%, 43% and 8.3%, respectively. Its gross calorific value was 32.9 MJ/kg, its percentage of volatile matter measured 30.6 and the fixed carbon content was 66.3% (d.a.f). Caking tests showed the optimal concentrate has a standard welling number of 1 and is a Gray-King coke type C. These results show that the optimal flotation product could be utilized for such industrial purposes as steam raising or for processing in gasworks, but it would be unsuitable for metallurgical coke production.

Jan 1, 1993

By R. B. Toombs

In describing the Canadian mineral industry in a world setting, this paper examines the industry from four points of view. First, mineral industry growth is related to trends in economic activity thereby providing a measure of the industry's importance in the Canadian economy. To give perspective to the Canadian scene, reference is made to economic trends in several of the world's leading mineral producing and mineral consuming countries. The Canadian mineral industry is next examined in terms of its major developments of the past 20 years and the resultant size, structure, and production diversity of 1964. The position of the Canadian mineral industry in the world industry is then analyzed by tracing changes in mineral supply and demand patterns. Growth of the Canadian industry depends greatly on expansion of export markets because three fifths of the value of production is accounted for by exports. Finally, attention is directed to the outlook for the Canadian mineral industry. Problems facing the industry are surveyed, and an appraisal is made of economic policies that have encouraged industry growth. A forecast of mineral production value in 1970 is included.

Jan 1, 1964

By Arif Emre Dursun, Ali Aras, Hakan Özşen

Specific energy (SE) is defined as the amount of work required to cut a unit volume of rock and is used to estimate the performance of excavation machines. Generally, the SE value is produced from full-scale or small-scale rock cutting tests. However, these tests require expensive equipment and experienced personnel, and the testing procedure is time consuming and impractical. Therefore, for estimation of SE, this study aimed to find a solution to estimate SE using rock mechanics test results and Bond work index values (BWi), which can be produced in a more practical, less time-consuming manner and with inexpensive test equipment. Small-scale rock cutting, rock mechanics and Bond work index tests were carried out on seven rock samples, which can be grouped into two different type of rocks: marble and travertine. In addition, the instantaneous cutting rates (ICR) of a selected roadheader were calculated using SE values. Rock mechanics tests performed in this study were uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), ultrasonic velocity (Vp), Schmidt rebound hardness (RL), corrected point load index (Is(50)) and density (ρ). The simple regression method was used to estimate SE from rock properties and BWi. As a result of this simple regression, a significant and highest correlation was found between SE vs. UCS and Is(50). A good correlation was found between SE vs. BTS, RL and BWi values. A moderate correlation was found between SE vs. Vp and ρ.

Jul 28, 2021

By Richard J. Lewandowski

Corrosion and product contamination have been difficult problems for extractive metallurgy industries in the U.S. because of the highly active chemicals used. During the past twelve years, other industries, particularly the chemical and paper segments, began to combat this problem with some degree of success using newer materials of construction, including reinforced plastics. These materials are made by combining a corrosion resistant thermosetting resin with a glass fiber reinforcing material and are used to con¬struct hoods, stacks, blowers, tanks, towers, pipe, and equipment of the most complex configurations. For service in contact with aggressive chemicals, the equipment is most often fabricated with the bisphenol-A fumarate polyester resins because of their resistance to corrosive attack. Data from both laboratory work and case histories of field applications are presented-for many common chemicals found in extractive processes. Information is also presented concerning design standards and recommended construction procedures

Jan 1, 1970

By A. S. Macfarlane

Over the last few years, and especially the last few months, issues relating to Corporate Governance in industry in general, and the Minerals industry in particular, have become increasingly topical, as a result of a number of scandals and failures. The development of International and National Codes for the reporting of Mineral Resources and Reserves began some years ago, and has been followed by more stringent Listing Rules for the Securities Exchanges, as well as more standardised formats and protocols for financial reporting of assets and activities. More recently, some countries have adopted Codes for the Valuation of Mineral Properties, which have focussed on standardisation of valuation approaches to be adopted, and the qualifications of people deemed competent to sign off such valuations. This process has not been without criticism, the main criticism being the proliferation of local standards and regulations, which are often difficult to apply and regulate, or which are too prescriptive for multinational mining companies to deal with. In South Africa, these concerns have been recognised, while at the same time a need has been identified to establish a Code which could be applied to South Africa, and the African continent as a whole. Such a development would necessitate that the Code satisfies the needs of the continent, but in a global context. This global context has already been set by the activities of the International Organisation of Securities Commissions, the International Valuations Standards Committee and the International Accounting Standards Board. This paper explains the progress and process that has been established in South Africa for this purpose, and highlights the key issues which are open to public debate, so that the process is inclusive and transparent, whilst at the same time it is consistent with international time frames, and provides a deliverable product that meets the desired objectives.

Jan 1, 2004

By David H. Carlson

The paper presents background information including data on diesel exhaust pollutants, amounts produced and standards, a desscription of mine characteristics that affect air monitoring techniques and a review of portable measurement techniques and instruments for gas and particulate matter sampling. A general review of the laboratory and field research being conducted at Michigan Technological University in the area of diesel emissions is presented. The facilities involved with this research are also described. These are the Experimental Mine, the diesel dilution tunnel test cell, the Mine Air Monitoring Lab (MAML), the portable instruments and the production mines used.

Jan 1, 1979