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By W. Guiye, L. Chongjun, L. Huinan, Z. Yangge, H. Long

The current application of copper-molybdenum (Cu-Mo) separation inhibitors is often associated with large dosage, high toxicity, environmental pollution problems. In order to solve these problems, a light sensitive Cu-Mo separation inhibitor LS（light sensitive inhibitor，abbreviated to LS） was developed. In this paper, inhibitory performance, photodegradation rule, and acting mechanism of LS were studied. The subsequent test results showed that, compared with traditional inhibitors, LS has shown comparative advantages, with lower dosage and good inhibiting effect. A series of flotation tests with LS as inhibitor were conducted on a Cu-Mo concentrate. A locked-cycle test showed that a molybdenum concentrate containing Mo 49.88% and Cu 0.6%, with 93.23% molybdenum recovery and a copper concentrate containing Cu 29.92%, with 99.99% copper recovery can be obtained. The photodegradation performance of the reagent was investigated under 365 nm, 254 nm and sunlight irradiation. The degradation of the reagents could be completely achieved by irradiation of three wavelengths of light. However, with the different wavelength of irradiation light, the degradation rate is different, the time required to reach 50% degradation rate being 3 h (254nm), 4 h (solar light) and 6 h (365nm) respectively. The inhibition mechanism on chalcopyrite was studied. FTIR study showed that LS could be adsorbed on the surface of chalcopyrite by chemical adsorption, which could enhance the hydrophilicity of chalcopyrite. Ultraviolet adsorption tests indicated that the adsorption capacity of LS on chalcopyrite surface was greatly affected by pulp pH value, and the proper pH value was 5-9. Keywords: Copper-molybdenum separation, Inhibitor, Light-sensitive, Photodegradation, Mechanism.

Jan 1, 2020

By Steve Kral

The list of environmental issues facing industry in general, and the mining industry in particular, has placed greater emphasis on the concept of risk assessment and risk management. In informal terms, risk can be defined as the chance of injury, loss or damage. More formally, it is defined as the probability of an occurrence and its consequences. In simple terms, risk assessment involves three questions: What can go wrong? How probable is it to go wrong? If it goes wrong, what are the consequences? Experts on the subject of risk assess¬ment and management met in St. Louis, MO in October 1992 to discuss the extensive and innovative technology that has been developed in this arena. Each agreed that a consistent framework can be used to approach risk assessment/ management considerations in siting and design alternatives, as well as when considering financial aspects of mine development. And the environmental planning process for mines, as well as planning for operation through closures, will rely more heavily on risk assessment and management techniques. Risk assessment is a tool to assist engineers, scientists and managers make better, defensible operational decisions. A realistic and probabilistic risk analysis, coupled with a sound financial model, can combine a large set of alternatives and criteria to arrive at a defensible decision. Organizers of this regional SME conference believe that mining professionals should become fully conversant with risk assessment techniques and approaches because this arena provides opportunities to develop more rational decision-making techniques. Current health risk assessments rely heavily on Environmental Protection Agency (EPA) approaches. Several speakers and papers show how this approach has been applied to a variety of topics. Two major advantages come forward when applying risk assessment techniques to environmental clean-up options for contaminated sites. They are the selection of practical options and cost-effective alternatives. A probabilistic risk assessment provides results that can be directly related to clean-up costs. It has been shown that small reductions in risk are obtained for large increases in cost after a certain threshold value is reached. A preferred, practical clean-up alternative that provides permanent solutions can be selected based on a probabilistic assessment. Here are summaries of some of the papers presented at the meeting.

Jan 1, 1993

By L Soares, W T. Hennies, F Fujimura

The engineering geological mapping of Metropolitan Area of Jopo Pessoa in the littoral zone of the Parafba State, northeast of Brazil, made possible the ambient characterisation for space using and its implications on the environmental resources. This region comes lately denoting an accented industrial growth and this work would help future projects of urban planning, distinguished by quick ground occupations for residential, industrial installations, farming, beyond mineral extractions. The mineral sector supplies material and substance demanded by industry and civil constructions, like as clay deposits, sands, calcareous rocks and mineral water. Many companies working there do not have the permission or inspection of ambient agencies for planned extractions of mineral resources. The consequences of this activity pass for the low profit of the reserves, bad uses of the sources, ground degradation, vegetation suppressions and physical impacts on landscapes, beyond noises and vibrations. These activities have causing accelerated alterations and transformations in the environment, compromising the sustainable development. It thus becomes clear that urgent solutions must be find to solve the problems with human interferences by closer inspection and management for disciplined use of its natural resources.

Jan 1, 2003

By C. Thomas Blevins

This paper is intended to be a hands on experience account about ground control in a Southern Illinois coal mine. Its aim is to show how a combination of real world mining practices and constraints along with practical engineering theory mesh together to formulate a ground control program in adverse conditions. These conditions - your typical localized slips, splits, rolls, clay intrusions, water, changing types and thicknesses of materials, etc. - being amplified by a very strong horizontal stress field. A review will be made about the formation of the overall ground control plan and to what degree it has been successful. A presentation of the various roof control systems and their component parts, how these systems were developed, and the theory behind them will be made. The pointing out of some of the flaws that we found in the components, installations, and/or theory will be part of this presentation. A brief look at some of the efforts in the following items will be made: quality control of the roof control products; using the computer to help keep track of roof control information and soliciting help from various universities, governmental agencies and consultants to give different perspectives to the problem.

Jan 1, 1984

By Julius Pohlman

Considering the truly wonderful natural resources of the United States, and the variety and extent of uses for hydraulic cement at the present day, it seems strange that the manufacture of the artificial product called Portland cement has not been introduced here. Possibly the reason may be we have in different States of the Union rock deposits from which a cement can be obtained that is as good, and some claim even better, because of a more uniform quality, than the English product after it has been subjected to transportation across the ocean. One of these natural cement-rock deposits is found in the northern part of the city of Buffalo, and its manufacture has been carried on successfully for the past eleven years by the Buffalo Cement co., Mr. L. J. Bennett, President. The quarries cover an area of about two hundred acres, of which only twenty-five acres have been exhausted up to date; and the supply is assured for years to come. One acre yields on an average 80,000 barrels of cement; hence 12,000,000 barrels is a low estimate of what these quarries will yield before they are exhausted. According to the Geology of New York this cement-rock deposit is called the Water-Lime group, and forms in this section the uppermost member of the Upper Silurian. Its outcrop can be traced along the base of the second limestone terrace of Western New York, but at Buffalo a very large part of the overlying Corniferous limestone has been removed by natural agencies, leaving only about eight feet (six feet of rock and two feet of clay) on the top of the cement-rock, and thus furnishing the conditions for successful quarrying at a minimum expense. This rock is really an impure limestone, a mixture, as it were, of the underlying shales of the Onondaga Salt group with the overlying

Jan 1, 1889

By David E. Hyatt, Christopher H. Cox, Franklin T. Davis

INTRODUCTION The composition of water used in the flotation process has always been of primary interest to the flotation metallurgist. It is by alteration of the chemistry of the water introduced to the process that flotation separation is effected. In only a few cases has it been necessary to treat available water prior to use in the process. In the past, flotation tailings were treated for the removal of solids via the tailings dam and water decanted from the dam was either recirculated to the process or discharged to the surface water system. The choice of recirculation or discharge was based upon water availability, effect of recycle water on the process, and economic considerations. The Federal Water Pollution Control Act Amendments of 1972 have charged the United States Environmental Protection Agency with establishing effluent limitations from point sources of discharge into the navigable water of the United States. A detailed study, sponsored by EPA, of the water of ore processing plants took place in 1974 and 1975 and guidelines for these plants will presumably have been published by the time this paper has been presented(1). The action of many of the individual states preceded the EPA in this attempt to regulate the quality of the water discharged from industrial point sources. Even with recycle of tailings water, some water is discharged from tailings dams into the substrata and at least one state is currently preparing guidelines for the quality of water discharged into the substrata.

Jan 1, 1976

By C. Cassios

EIA is a procedure aiming the elimination of adverse impacts to the environment from undertaken projects. Historically, it starts in 1969 when NEPA (Nat.Env.Prot.Agency) in the US initiated the EIA ? EIStatement. The EIA procedure was adapted by the European Union with the directive 337/85 and in Greece the Common Ministerial Decision 69269/90 enforced it to the Greek legislation. However, mining enterprises in Greece long before the implementation of the European Directive and in accordance to the legislation of the Public Law 998/79 for the protection of the forested lands were obliged to submit EIA?s and get an approval in order to operate in forested areas. The submitted and approved EIA?s and their implementation by the mining companies were among the positive aspects of the EIA procedures. This paper is examining the impacts of EIA?s in the Greek mining industry its positive aspects as well as their difficulties and their role for the reclamation procedure. The technical and procedural aspects which EIA presents for the mining industry are commented, while proposals, for a more flexible EIA implementation for the Greek Environment are also presented.

Jan 1, 2002

By G. M. Brownell

A DEPOSIT of hematite occurs on Black island, lake Winnipeg, at a point known locally as Red Rock, on the south shore of the island directly across from Clements point. The mail boat from the Canadian Pacific Railway terminus at Riverton, crossing the lake to Manigotogan twice weekly, passes near Red Rock and provides a convenient means of transportation to this part of Black island (Figure 1). HISTORICAL The occurrence of hematite on Black island has been known for a long time. Dowling's report of 1898 states(1): "An iron-ore deposit on the south side has been known' for many years, and on Jeffrey's map of 1762, showing Canada and northern part of Louisiana, Iron island is shown a short distance south of the narrows, evidently the same as the Black island of today".

Jan 1, 1945

By Russell R. McLellan

As part of an effort to develop new or improved placer mining technology in the Tertiary gold-bearing channel gravel of northern California, the Bureau of Mines conducted investigations at the old Badger Hill placer mine in Nevada County, Calif., to collect data and information regarding drilling and sampling methods and deposit characteristics. Sampling studies involved the collection and processing of 400 tons of large-and small-volume samples from drill holes, underground workings, surface pits, and blasthole rounds. A total of 355 samples averaging 2,296 pounds per sample provided reasonably accurate data for analysis of the gold distribution. These studies indicated that the bulk of the gold is within 40 feet of bedrock in stacked, lenticular zones of cemented gravel that are largely confined to the relatively narrow, meandering course of the deepest portion of the bedrock channel. Drilling studies involved the testing of truck-mounted rotary, buckett and vibratory drills, none of which proved to be a completely versatile tool for sampling quickly and reliably both consolidated and unconsolidated gravel..

Jan 1, 1974

By Y. Buro

The Bachelor Lake gold deposit occupies an ESE-trending, SW-dipping, silicified shear zone with hematitic alteration. It transects NE-trending, steeply dipping Archean volcanic formations and the O'Brien granite. Major W-SW and N- NE-trending faults have affected the ore zone and the emplacement of the granite intrusions. Movements along the WSW set may have opened the fractures filled by the mineralization. Gold is generally associated with pyrite. Its source, whether a granitic pluton or a volcanic sequence, is undetermined, but the granite probably provided the concentrating mechanisms through heat and hydrothermal solutions.

Jan 1, 1984

By Daryl L. Gusey, John T. Neubert, Matthew A. Sares

The Colorado Geological Survey completed an inventory of environmental degradation associated with abandoned and inactive mines on National Forest System lands in Colorado. In the course of the inventory, areas with naturally occurring acid rock drainage were also noted. Approximately 18,000 abandoned mine- related features were inventoried, including about 900 features that are considered significant enough environmental problems to warrant further investigation. Water quality data, such as pH and conductivity were gathered at all features where water was present, such as draining adits, seepage at the toe of dumps and tailings, and standing water in shafts. Samples were taken where field tests indicated low pH andlor high conductivity, including several areas with naturally occurring acid rock drainage. Samples were analyzed for dissolved and total metals, and for selected anions. All mine locations and data collected by the field geologists were entered on field forms and, subsequently, into a computer database and GIS format. With the information provided by the inventory, the Forest Service, in cooperation with other agencies, has been able to prioritize abandoned mines for reclamation. In most cases, cleanup is approached on a watershed basis. Mines in priority watersheds have been selected for reclamation first. Watersheds where studies prerequisite to cleanup are occurring include the upper Anirnas River, Willow Creek (tributary to the upper Rio Grande), Chalk Creek (tributary to the upper Arkansas River), the Uncompahgre River, and the Alamosa River. During the inventory, evidence of naturally occurring water quality degradation was found in areas where little or no evidence of mining activity exists. These areas include the upper Alamosa River, the Middle Fork of Mineral Creek, Peekaboo Gulch, and Handcart Gulch. Water from these natural sources has been found to significantly exceed Colorado water quality standards for several metals.

Jan 1, 2000

Activity with the legislation proposing to liberalize War Minerals Relief Act has now started before the Committee on Mines and Mining of the House. They are considering House Joint Resolution No. 170, which brings out the fact that war minerals claims in excess of $15,000,000 had been filed but that a considerable portion of the claims are being denied because of the Attorney General's. interpretation of the Act. The resolution states that it was the intention. of Congress in passing the War Minerals Relief Act "that all producers of the minerals mentioned should be repaid such sums as they are in equity and good faith entitled." The Attorney General's opinion is that the request or demand must have been made on the claimant direct. The resolution provides. that all claimants "who in response to any personal, written or published request or demand from any of the Government agencies-mentioned-in said Act in good faith expended money in producing or preparing to produce any of the ores or minerals named-therein *-*-* and have heretofore filed their claims within the time and-in the manner prescribed in said Act" are to be reimbursed for the n t-losses-incurred.

Jan 12, 1919

By Karl Zipf

In highwall mining, once a sufficient number of web pillars are developed, they can fail catastrophically in a domino-type failure, posing a safety hazard to highwall miners and sterilizing mineable reserves. Three recent case histories of catastrophic web pillar failure in U.S. and Australian mines are documented and analyzed with two design approaches. The conventional design approach uses only a strength criterion, while the postfailure design approach uses both strength and stability criteria to insure an acceptable failure mode should strength failure occur. Catastrophic highwall web pillar failures can cost money through equipment losses, production losses, coal reserve sterilization and lost opportunity costs. Coal recovery may be higher. but the benefits of higher recovery must balance the potential costs of failure. Application of the conventional or postfailure design approach will decrease coal recovery and revenues, but the risk of potentially costly failure is much less.

Jan 1, 1999

By Sallie McCabe Johnson

LIFE IN RUSSIA for the foreign woman is hard. It is up to her whether her days are spent in tearful longing for ironic or whether she :hakes the real effort to ferret out the interesting or amusing side of such exasperating conditions as ooh a Russian can conjure. So to begin Discard all promises.. This is perhaps the most difficult thins- to learn but promises in Russia are nut what they are at home. There are many reasons for ibis, sonic good and some bad but whatever the reason. the fact remains that they are usually worthless- as each of us must slowly learn In, disappointment after disappointment. Also we must learn that we cannot expect to get or to do a certain thing just because someone else has done so. What we did yesterday perhaps cannot be dune today. What we purchased air hour ago, oxen ten minutes ago- we cannot purchase now. What our neighbor did this morning we cannot do this afternoon. Changes arc continuous. Every person's experience is different from that of another aid this in a great measure accounts for the conflicting stories brought horns. In a land of chaos we live only from hour to hour and this is one of the exceedingly exasperating conditions to face. When I wished to visit Leningrad, an overnight nip from Moscow, more than a week's lime w as required to obtain a ticket, vi en through the efficiency of lntourist: alone I might have spent a month at it. Each day

Jan 1, 1932

Now that Japan has achieved a remarkable high growth and joined the ranks of economic powers, she is required to take a stance proper to her new position toward international co- operation among Western advanced countries, economic/technical aids to Southeast Asian and Pacific LDCs, and others. As a field subject to such international cooperation programs, the development/use of coal resources has been winning increasing attention in recent years. Coal is positioned as one of promising alternative energies. With Southeast Asia plus Japan and the EEC serving as the two nucleus polar regions, total coal demand in the free world is projected to jump 37% in the year 2000 from the present level and steaming coal imports in the world, primarily destined for power generation, almost double the 1983 level. Such being the situations, Japan's tech- nologies related to coal resource development, if successfully introduced into coal-producing countries to help them boost their production, can directly lead to international cooperation that Japan is now required to fulfill. At home, however, the Japanese coal industry has been just on the wane due to various press- ing problems, such as wider differentials between overseas and domestic coal and deeper/ remorter mining. The industry was named atop in a list of the industries requiring restruct- uring at a meeting of the Economic Structure Study Committee held prior to the decision- making of the 8th coal policy, which slashed coal production planned for the last fiscal year of its life to some 10 million tons, a drop of as much as 50% from nominal output planned in the 7th policy. Under such circumstances at home and abroad, a pioneer study has been under way since fiscal 1984 as part of Japan's energy cooperation in the Pacific. The study is based on the Pacific coal flow concept hammered out by the Agency of Natural Resources and Energy of the MITI.

Jan 1, 1987

By H. T. Michels

Recent laboratory studies show that several bacteria, known to be human pathogens, die when they come in contact with copper and copper alloy surfaces. The amount of live bacteria drops by several orders of magnitude, to zero, on copper alloys in a few hours. In contrast, no reduction is seen in the concentration of live organisms on stainless steel during the six-hour test period. Aluminum painted and coated surfaces and plastics would show behavior similar to stainless steel and show no effect. Coatings and other surfaces claiming to be antimicrobial showed little to no effect. These results suggest the selection of copper alloys for surfaces exposed to human touch can materially assist in reducing the transmission of infectious organisms. In order to make antimicrobial claims in the United States, the approval of the US Environmental Protection Agency (EPA) is required. The EPA-required efficacy testing is described and the test results are summarized. It is anticipated, that once regulatory approval is obtained, that this will facilitate the introduction of antimicrobial copper alloys in hospitals, nursing homes and other healthcare facilities, as well as schools, and public buildings. Some of the application and barriers, to entry into the healthcare markets are mentioned.

Jan 1, 2007

By A. K. Sinha, K. M. Sinha

Several studies concluded by various agencies (Coal Outlook, 1982; Malhotra, 1977) indicate that both the national and international markets for utility coal, which have been growing in recent years due to the uncertainties in petroleum supplies, will continue to grow in the foreseeable future. The areas where the Gemand for utility coal is projected to increase sub- stantially lie close to the midwestern coal fields, in the southeastern US, and in western Europe. Illinois has all the elements necessary to become an important exporter of thermal coal (Library of Con- gress, 1981) provided the coal is desulfurized to meet the environmental restrictions. Because of its high energy content, Illinois Basin coal, if desulfurized, has great potential for competing in the utility markets both nationally and internationally. Sulfur in coal occurs in organic and inorganic forms. The inorganic sulfur in Illinois coal is almost exclusively pyrite. The pyrite can be liberated by grinding and removed from the coal by such techniques as froth flotation. The Illinois Basin coals reportedly contain (Gluskoter and Simon, 1968) an average of 3.57% sulfur. Out of this, 2.06% is pyritic, 0.08% is sulfate, and 1.46% is organic sulfur.

Jan 1, 1986

By H. F. Haller, H. C. Pattison

The research program described in this paper is sponsored by the Advanced Research Projects Agency of the Department of Defense and monitored by the Bureau of Mines, United States Department of the Interior. PROGRAM DEVELOPMENT While Holmes & Narver is better known in other fields, the company has been active in many phases of underground excavation for over twenty years. In the 1950's, H&N participated in design and construction of nearly twenty miles of waste disposal tunnels in Southern California. As Architect-Engineer for the Atomic Energy Commission, we had design and management responsibility for many miles of tunnels and for thousands of feet of exploration and big hole drilling, from coast to coast in the States, and for gas well completions and exploration drilling for the Navy and the National Science Foundation from Pt. Barrow to Byrd Station in Antarctica. In my ten years with the company, we contributed to the development of big hole drilling techniques at a number of sites and analyzed the capability of boring machines for many of the tunnel projects. In a 1965 engineering study of a hundred miles of vehicular tunnels in rock under New York City, we investigated

Jan 1, 1997

By Link. Theo A.

Introduction Since the discovery of a major oil pool at Leduc, Alberta, on February 13th, 1947, the long spell of 'oil drought' in Western Canada is now being turned into an oil and gas flood which requires immediate action to obtain the optimum economic benefits. The Woodbend, Section 9, and Okalta extensions of the Leduc field itself have been established; the Redwater pool, lying thirty-seven miles northeast of Edmonton, has been discovered and is being drilled up, and the Imperial Schoepp No. 1 or Golden Spike discovery holds promise of something phenomenal in view of the 500 feet of oil-saturated coral-reef porosity whose areal extent is not known. Imperial Stanolind Barrhead No. 1, northwest of Edmonton, revealed the presence of oil in the Madison, and just recently Gulf N.J. Ellis No. 1, some sixty miles southeast of Leduc, found commercial production in the Leduc D-2 discovery zone. In addition to these Paloeozoic discoveries, gas and oil reserves have also been established in the Upper and Lower Cretaceous, which must be penetrated by all tests on the way through the geological column to the Devonian. If ever there appeared to be an index of 'things to come' in the oil industry, this is it. However, without these recent discoveries the picture in Western Canada does and always did, look very promising indeed. A brief survey of the geological setting in Western Canada is the object of this contribution.

Jan 1, 1949

Recovery Efficiency Study on Ilesha Placer Gold Ore by Flotation Using Locally-Sourced Frothers and Collectors

Sep 13, 2010