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By C W. Lu, Y F. Chen, M J. Lian, W W. Guo

This paper proposes a set of new approaches for the optimisation of planning and designs in mines by means of evolutionary algorithms, which include the determination of ore grade, layout of development system, selection of mining methods and production scheduling in underground mines. The applications indicate that evolutionary algorithms are particularly suitable to the complex and complicated problems in mines.

Jan 1, 2003

By Gerardo H. Achurra

During the last years, the Caletones Smelter, like others copper smelters in the world, has evolved from the conventional, inefficient, pollutant and expensive technologies, to modern, environmentally friendly and efficient ones. For this reason' as well as to improve its competitive position this Smelter shut down the reverberatory furnace, started up two big acid plants and has developed some pyrometallurgical technologies. The main facilities of the Caletones Smelting and Converting Process, in the present and the future, are the Teniente Converters, the reactors with a high operational availability that have reached concentrate top process capacities near to 2,400 tpd. These reactors operate in most of Chilean smelters as well as in other smelters in the world such as in Zambia, Peru and Mexico. Since 2000, the Caletones Smelting and Converting Process, has been adapted in two Teniente Converters, four Slag Cleaning Furnaces and four Pierce -Smith Converters. These facilities, together with the operation of two Fluidized Bed Dryers and two Oxygen Plants have allowed to reach concentrate smelting capacities and copper productions of 1,250 ktpy and 380 kfipy, respectively. Associated to EI Teniente Division Expansion Plan, Caletones Smelter, in the first stage, will increase its capacity to 1,440 ktpy in 2004. In the long term, Caletones has different options, such as the processing of 1,600 to 2,000 ktpy of concentrate, producing anodes, white metal or a mixture of them. These options are connected with CODELCO's Smelters & Refineries Strategic Plan, including Mejillones Project. The main challenges of Caletones Smelter are associated to the development and the consolidation of the Continuous and Environmental Friendly Processes, automation and control of different processes and to the improvement of its leadership between other Copper Smelters in the world.

Jan 1, 2003

By Marcio Toshio Tanaka, Marcelo Breda Mourao, Cyro Takano, Cesar Yuji Narita

"The concerns in questions related to the environmental impact in the steelmaking industries caused mainly on the gas emissions such as the dioxide carbon are due to its raw material such as the coal, a fossil and non renewable resource. The purpose of this paper is to replace from 10% to 50% of the coal used in cokemaking by mixing it with a renewable source (wood charcoal). The powder (- 325 mesh) from both raw materials (coal and wood charcoal) were mixed in order to obtain a briquette that was then heat treated at 1100°C to obtain the biocoke. Results of usual analysis (coke reactivity index, coke strength after reaction and cold crushing strength test) were employed to compare to regular coke briquettes. It was found that biocoke with different amounts of wood charcoal present features enabling it to be used in some ore reductionprocesses.1. IntroductionThe iron and steelmaking industry is a heavy emitter of carbon dioxide; according to the World Steel Association, 6.5% of global emissions of this greenhouse gas is due to the production of ferrous materials [ 1]. This is due to the fact that the fuel and reductant employed in the blast furnace is metallurgical coke, obtained from fossil coal. There are some projects aiming to reduce or even eliminate the emission of fossil GHG in the iron and steelmaking process [2]. Most of them propose the capture and storage of the gas (CCS) [3], a technology not yet proven. Other studies point out that the coke consumption in the blast furnace could be reduced by using high reactivity coke; this could lead to lower temperatures in the thermal reserve zone of the blast furnace and consequently less fuel rate in the furnace.The use of biomass in the iron ore reduction process is known as an environmentally accepted solution, as biomass does not release already fossilized carbon."

Jan 1, 2013

By Omar A. Muhtadi, R. Bruce Thorndycraft, David A. Milligan

9.1 INTRODUCTION Precious metals in a leach solution are extracted, concentrated, and purified to complete the process begun in the heap and to produce an end product which will provide an economic payback to the mine developer/operator. Several different processes are required to convert the dissolved precious metals into pure metal bars. This chapter discusses the actual production of metal once it has been recovered from the pregnant leach solutions by the zinc cementation (Merrill -Crowe) or carbon adsorption processes. Metal production is generally taken to mean the production of a fairly pure "dore" bar. This chapter also reiterates some information from Chapter 8 in a slightly different context, since the focus of Chapter 8 was a fairly detailed description of the two actual recovery processes, whereas the focus of this chapter is metal production. The sale of an intermediate precious metal product is possible (as opposed to the production of dore bars at the mine site); however, the value of the precious metals is reduced by the various charges and risks associated with precious metal processing. For this reason, most operators choose to produce the most refined metal possible in order to maximize project economics. Precious metals may be extracted from the leach solution by both conventional and unconventional processes. The conventional processes are activated carbon/electrowinning (ACE) and zinc precipitation (ZIP). The unconventional processes are resin ion exchange, solvent extraction, and direct electrowinning. A typical ACE process has two circulating loops. The first loop adsorbs the cyanide-metal complexes from the dilute leach solution onto the activated carbon. A second, separate solution loop removes the cyanide-metal complexes from the activated carbon into a strong solution, the electrowinning electrolyte. Activated carbon is transferred from one fluid loop to the other. The operating cost of the ACE process is directly proportional to the quantity of carbon stripped and thus to the quantity of precious metal produced. A typical ZIP process contains a single circulating loop. The solution is filtered, deaerated, contacted with zinc, and filtered again. The barren leach solution is then returned to the heap. The zinc sludge recovered in the

Jan 1, 1988

By Robert B. Fulton

Commercially, celestite (SrSO4) is the predominant strontium mineral. Among other strontium-bearing minerals, only strontianite (SrCO3) occurs commonly; however, it is rarely an item of commerce. Production of celestite is principally in Mexico, Spain, and Turkey. An attempt to produce celestite in Canada was unsuccessful. The United States, which is wholly dependent on imports, chiefly from Mexico (99%), is the largest consumer of strontium. Lesser quantities are consumed in Japan and Europe. The Federal Republic of Germany is the principal source of strontium compounds imported to the US. Uses The principal uses of strontium are for the manufacture of strontium carbonate and nitrate. Carbonate is used in glass for TV tube face plates and in ceramic ferrites for magnets. Nitrate is used in pyrotechnics, mainly in safety flares, to which it imparts a characteristic brilliant red color. Minor amounts of strontium compounds are used in electrolytic zinc manufacturing where the carbonate is used to remove unwanted lead. Small quantities are consumed in greases, ceramics, soaps, alloys, and pharmaceuticals. Specifications Typical celestite specifications for the carbonate and nitrate markets are shown in Table 1. Specifications of manufactured carbonate, sold in two grades, one to the glass industry and the other for ceramic ferrites, are shown in Table 2. Both grades of carbonate are shipped in palletized 50-lb bags. Glass grade material is shipped in bulk by rail. [ ] Manufacturing Processes The following description is adapted from Anon. (1980) . The manufacturing process for strontium carbonate and strontium nitrate chemicals is conceptually simple. Strontium nitrate is made from strontium carbonate in two additional steps. The production process begins with celestite, the natural form of strontium sulfate. In the first step the ore is crushed, ground, and mixed with coke. This mixture is then fed into a kiln where the ore is reduced at high temperatures to strontium sulfide; the coke is added to the ore as a source of energy and carbon. The carbon combines with the oxygen [ ]

Jan 1, 1983

By Cooper P. G

I he Electrolytic Refining and Smelting Company (ER&S) has oper- ated a copper smelter at Port Kembla, NSW since 1908. The feasibility of modernising the smelter was recently studied and external influences were shown to have a substantial impact on the project economics. Profita- bility is determined by the relative magnitudes of treatment charge income earned from processing raw materials and the operating costs incurred. Treatment charges are usually denominated in U.S. dollars and are deter- mined by market forces in the world copper industry. ER&S is no different from other Australian manufacturing industries in that it must maintain its competitive position by controlling costs. The modernisation project seeks to achieve this through new technology and improved labour Productivity.

Jan 1, 1988

By P. Thapliyal

The petroleum refining industry generates over a million tons of spent catalyst per year, containing valuable metals. Currently, these materials are recycled to smelting furnaces, but the fundamental mechanisms controlling the recovery processes are poorly understood. Furthermore, submerged injection of finely divided materials is potentially a means to obtain high recoveries of pay metals. In this study, a catalyst containing 10% Ni and 1% Co was injected into 45 kg heats of matte. A copper matte was chosen so that the nickel and cobalt recoveries were measurable. It was found that the recovery ranged from 40 to 700Al, increasing with catalyst feed rate, decreasing with catalyst particle size and decreasing with the oxygen content of the carrier gas. A mathematical model was developed to account for the results, and to permit extrapolation to nickel mattes. The industrial implications are discussed.

Jan 1, 1996

By Eoffe SW

The wide application of computers in beneficiation plants has resulted in the creation of a number of complex automatic control systems at all stages of ore dressing processes. To create such systems it is necessary to solve complex problems of analysis and calculation. The application of computers to solve these problems demands development of simple and effective methods of investigation and simulation of ore dressing process dynamics because all the known methods are complicated in usage and cannot guarantee the desired accuracy and quality of process control. A new grapho-analytical method of investigation and calculation of ore dressing flow sheet dynamics, worked out by the authors of this paper, is based on proportion method development and is used to construct dynamic characteristics of the investigated processes. It is possible to use the given method for investigating benefication schemes with flotation machines having non-linear static characteristics and circulating loads. The suggested method of investigation of concentration flow sheet dynamics allows us to obtain dynamic characteristics of technological process parameters in both linear and non-linear systems. Moreover, the final result can be obtained without labour consuming analytical calculations by a simple graphical construction based on the static characteristics of the known equipment and processes.

Jan 1, 1993

By Y. Ye

Induction times for a variety of minerals have been measured at a particle bed. Electrostatic repulsive forces between bubble and particle generally are of secondary importance in determining the hydrophobic state; nevertheless, the shortest induction times are measured at the isoelectric point of the solid. More importantly, the study shows that the film-rupture mechanism at a polished surface might be different from that at a particle bed. The induction time measured at a particle bed, besides being dependent on the surface chemistry of the system, shows a definite relationship to particle size and density. Theoretical analysis suggests that such a measured induction time at a particle bed should properly be defined as an attachment time which consists of the induction time and the film-displacement time. Thus one portion of the measured attachment time is the induction time, the time required to thin the water film between the particle surface and the gas bubble to a critical thickness so that rupture of the film takes place ('1)' The other portion of the measured attachment time is the time required for the film to be displaced to such an extent that the attachment is stabilized with respect to the upward motion of the bubble and the downward gravitational force acting on the particle ('2)' Further, the present study illustrates that '2 is related to the hydrophobic character of the surface, the rate of film displacement after rupture, the upward velocity of the captive bubble, and, most importantly, the particle size and density.

Jan 1, 1988

By Nick Poushinsky

OVERVIEW OF PRESENTATION ?Stantec?s Northern Presence ?Challenges for Northern Development ?Environmental Approval Challenges ?History/Expectations ?Baseline Data ?Consultation ?Regulatory Processes ?Extra ?Regulatory ?Keys to Success

May 1, 2009

By Richard M. Winar

In September of 1988, the United States Environmental Protection Agency (US EPA) published final regulations that effect owners and operators of underground storage tanks (USTs). These regulation include stringent technical requirements for owners and operators of USTs containing petroleum and certain hazardous substances. The technical requirements effect both new (those installed after December 1988) and existing USTs and include notification; performance and operating standards; release detection, reporting, investigation; release response and corrective action; and closure requirements for out-of-service USTs. The USEPA also published final regulations regarding financial responsibility requirements for owners or operators of petroleum USTs in October of 1988. These regulations require owners or operators of petroleum USTs to demonstrate financial responsibility for the costs of corrective action and compensating third parties for bodily injury or property damage caused by releases from petroleum USTs. Like thousands of other industries, the mining industry must become thoroughly familiar with these new regulations in order to properly manage their UST systems, ensure compliance, and understand other ramifications imposed by these regulations.

Jan 1, 1990

By S. Narra, M. Nelles, I. Eickhoff, S. Teitge

"The aim of the research is to develop a holistic process flow for the recycling of glass fibres from glass reinforced plastics (GRP) and carbon fibres from carbon fibre reinforced plastics (CFRP), wherein the dissolution of the fibre epoxy resin matrix, separation of fibre fractions and their renewed material use is intended. In clear distinction to the previous research and development projects, the aim here is to recycle complex composite structures such as dismantled/disused wind turbine rotor blades and end-of-life composite wastes. In the course of the study, mechanical, hydrothermal and thermal processes and their combined procedures will be developed. As the fibre length is a decisive quality criterion in the recycling of composite materials, the further focus of the study will be the development of upstream and downstream material processing, in which the fibres are retained in their original form. The evaluation of the recycled fibres obtained is based on the elemental composition, measurement and morphological evaluation of individual filaments by scanning electron microscope (SEM), micro tensile tests on single fibres and their comparison to virgin fibres. The resulting process water is analysed by gas chromatography and mass spectroscopy (GC-MS) and a potential recirculation is determined. In cooperation with companies from the composite processing industry as well as recycling companies, a return of the recycled fibres to the known manufacturing process will be examined and an energetic and economic evaluation of the overall process will be carried out. Ambitious aim of the study is to achieve an actual recycling instead of the present downcycling or the energetic utilization. INTRODUCTION As global warming increases, so does the awareness of consumption and production of energy. To counteract the effects of global warming, renewable energy has been increasingly used during the last two decades, not only in Germany, but worldwide. Both, hydropower and wind energy, hereby play a fundamental role. After the end of their useful life of 20 to 30 years, the wind turbines (WTs) are being dismantled. Due to their foundations and tower segments, their recycling rate hereby exceeds 90% by mass. So far, the resulting rotor blade waste played a minor role accounting for only 2 - 3 weight-% of the total plant. Rotor blades of modern wind turbines are made of glass and carbon fibers, which are embedded in an epoxy or polyester resin matrix, balsa wood, PU or PET foams as fillers as well as various paints and coatings. These wastes currently end up in waste incineration or are sold to non-European countries."

Jan 1, 2018

By J. D. Doherty

That America's great coal deposits eventually will be our principal source of liquid as well as solid fuels is generally accepted. Moreover, the day when synthetic oil from coal will begin to supplement our petroleum supplies does not appear to be far off. The American petroleum industry has not spared effort or expenditure in its attempt to keep pace with the demand for oil, and recent production has exceeded expectations. However, the rapidly rising demand for liquid fuels plus the increasing difficulty of finding and developing the new oil needed even to maintain present production rates make it highly unlikely that oil from domestic wells can fully meet future oil requirements. Therefore, it appears that one or more of the following courses must be followed: 1. Curtail oil consumption. 2. Incr ase imports. 3. Develop new sources such as synthetic liquid fuels. All three courses may well be needed, as it is doubtful that any one of the three alternatives alone can satisfactorily solve the problem indicated by the prevailing trend in demand for oil. Curtailment of oil consumption is not a constructive policy, except where oil is being wasted or coal can be readily substituted as in stationary steam plants. Reduced oil supplies for most uses will curb our economic advancement and, in addition to inconveniencing consumers, will have a pronounced adverse effect on American industry. The oil-burner-manufacturing industry already has been dealt a hard blow. Shipments in the first 5 months of 1948 decreased 70 pct from those in the same period in 1947.1 The effect of a similar cut in the automobile industry can be imagined. A severe prolonged shortage of gasoline could seriously disturb our present economic well-being. It might be pointed out also that even the prospect of a shortage or lack of assurance for the future can discourage buyers of equipment, as occurred in the case of oil burners. An increase in our imports of oil seems to be a necessary expedient for the immediate future. Its advantages are that it will require a minimum of manpower and steel in a time of critical shortages and will conserve domestic reserves. Any major dependence upon foreign sources for our oil supplies should be avoided, however. Other nations are increasing their oil consumption more rapidly percentagewise than the United States and eventually will compete with us for the not unlimited world supplies. In peacetime, foreign countries might restrict ship- ments of oil to this country or impose exhorbitant prices. In the event of war, there is serious danger that such sources would be cut off, and American-developed oil fields overseas might even be used against us. Although synthetic fuels cannot relieve any oil shortage that might develop within the next year or two, an immediate start toward a substantial synthetics industry to supplement petroleum not only could help relieve shortages several years hence but also would help establish the much needed "know-how" for large-scale production. By assuring ample future supplies, such a start would permit sound planning by industries dependent upon oil and maintain or restore the confidence of prospective customers for oil-con-suming equipment. If it is agreed that domestic production of crude oil cannot be expected to meet future domestic demands, that oil rationing in general is undesirable. and that too great dependence on foreign oil should be avoided—and the weight of the evidence supports such conclusions—it is inescapable that commercial synthetic fuel production should be developed to supplement domestic petroleum supplies, which, of course, will furnish the bulk of our requirements for yean to come. Sources of Synthetic Oil The three principal sources of synthetic oil are natural gas, oil shale, and coal. A commercial plant using natural gas is under construction, and expansion of this industry is expected.

Jan 1, 1950

By Satayev IS, Shepelev DV

Various ways for applying the X-ray fluorescent method to process lump-by lump separation of secondary aluminium raw materials (scrap, slags, waste) as well as ferrosilicon and ferrochromium are being considered and physically demonstrated. A commercial X-ray radiometric sorter has been developed for processing secondary raw materials. Marketable quantities of aluminium scrap with appropriate copper and zinc content have been produced for smelting with a minimal additional of pure aluminium. An industrial complex for scrap processing, incorporating two X-ray radiometric sorters from the Hammermils company is successfully operating at one of the works in Russia.

Jan 1, 1993

By Frank P. Frandina, Diane R. Hirsch, David P. Field, Colin R. Weeks

To accommodate growth in air service and to follow the Master Plan for long-term airport development, the Metropolitan Washington Airports Authority established thed2 Development Program at Washington Dulles International Airport. A sub-surface Automated People Mover (APM) System is under construction to replace the Mobile Lounges as the primary people mover system at Dulles. To minimize disruption to airport operations the majority of the APM System’s crossings of Taxi lanes will be undertaken using Tunnel Boring Machines (TBM) or the New Austrian Tunneling Method (NATM). This paper explores the planning and design of these shallow tunnel segments for future generation aircraft loads, within the constraints of minimal construction access under post 9/11 security requirements and the context of the overall airport expansion program.

Jan 1, 2005

By E. C. Baker

Costs of disposing of steel slag are estimated based on the present method and a proposed alternate method for a steel mill in the Pittsburgh area. Estimated cost data were calculated by the Bureau of Mines and do not reflect the investment and operating costs and credits of a specific steel mill and processing plant. The alternate method of steel slag disposal would result in an appreciable cost savings to the mill and concurrently supply the industrial and commercial markets with low-cost, high-quality construction materials.

Jan 1, 1970

By Forrest T. Moyer

The safety record of the metal mining and milling industries in 1965 is reviewed by the Bureau of Mines. The overall injury-frequency rate of 23.77 per million man-hours was 5 percent lower than in 1964 and was the lowest annual rate in a statistical history beginning with 1931. The injury-severity rate of 3,521 days lost per million man-hours in 1965 represented a 5-percent improvement over 1964. However, the total of 3,825 disabling work injuries comprised 61 fatal and 3,764 nonfatal injuries, one and 92 more, respectively, than in 1964. At primary nonferrous smelters, refineries, and reduction plants, the injury-frequency rate of 8.97 per million man-hours in 1965 was 13 percent lower, but the severity rate percent higher than in 1964. these plants in 1965, 4 more of 1,173 days lost per million man-hours was 17 There were 12 fatal and 971 nonfatal injuries at and 28 fewer, respectively, than in 1964.

Jan 1, 1969

By A. K. Snelgrove

Introduction ?Concerning the inland commodities, as wel to be drawen from this land (Newfoundland) there is nothing which our East and Northe.rly countries of Europe doe yeelde, but the like also may be made in (ît) as plentifully by time and industry : Namely, rosen, pitch . . . metalls, and many moe. All which the countries will aford, and the soyle is apt to yeelde ... For besides these alreadie recounted and infinite moe, the mountains generally make shew of minerall substance : Iron very common, lead, and somewhere copper. I will not auerre of richer metalls: albeit ... more then hope may be concieued thereof. " - Narrative of Captain Hayes, second-in-command to Sir Humphrey Gilbert's Expedition, IJ83 (From Hakluyt). The investigations set forth in the following pages were made in the field in Newfoundland during the summer of 1927, and later in the laboratories and library of McGill University, and in the library of the Canadian Geological Survey at Ottawa, with the purpose of collating and adding to our knowledge of the geology of an area roughly wedge-shaped in outline, and nearly nine thousand square miles in extent, stretching across the centre of the island of Newfoundland, from the southwest to the northeast coasts. To the description of this district, which contains most of the known mineral occurrences of Newfoundland, the term mineral belt is here introduced.

Jan 1, 1928

By T. E. Kobrick

When Ralph Banks called and asked if I would agree to present a paper on environmental health in the coal industry, I was reluctant because I have not been actively involved in coal mine dust control on a day-to-day basis for a number of years. Ralph reminded me that I am one of the few industry people with an industrial health background who remembers the pre-1969 Federal Coal Mine Health and Safety era. This marks the second time within the past year that I have had a similar request based on the same basic reasons. While I was pleased to have been remembered, I'm beginning to feel like the football player who has played one too many games. In responding to Ralph's request to present an overview of the past, present and future of environmental health in the coal industry, I have attempted to take the broad approach of someone who, having been intimately involved in an area of endeavor for a number of years and then leaves, has an opportunity to revisit that area at a later date to see what has changed and what remains the same, what have been the successes and the failures. Since none of us can foresee the future, trying to project too far ahead is fraught with frivolity, except that unless one is foolish enough to accept a future invitation to review those predictions compared to actual events, no one will recall how accurate or inaccurate those projections might have been. I can assure you that I will not ask to accept that challenge, so you can rest comfortably that five years from today you will not be asked to sit through a similar presentation by me - and that's a promise.

Jan 1, 1985

Competitive commercial circumstances internationally provide a prime impetus for miners to seek new technologies as a means to profitability and survival. Engineering and project management activities play a vital role in establishing, operating and developing the capital facilities used by miners. Computer based technologies are the single most important technology for maintain- ing competitiveness in engineering and project management into the future. Current applications of computers in engineering design and drafting are finding economic applications, computer-aids are more readily introduced, accepted and profitable. Computing technology is advancing very rapidly and on a broad front in hardware, software and communications. This technology advance is improving the ability of engineers and project managers to provide a high quality, responsive and low cost service which will improve in parallel with computer technology. As this technology advances, a key challenge is created for managers in selecting hardware and software, in developing people and organisations and in marketing the technology to advantage. While the future holds many exciting developments, people will still hold the key roles. While the nature of their roles may change, the final acceptance or rejection of technology will be by people, whether as users or owners, who will judge on the basis of whether their stake is improved or not.

Jan 1, 1986