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By X. M. Yu

A large amount of polluted sludge is produced by a nonferrous metal factory after treating waste water with lime/ferrous salt. The concentration of arsenic in the dried sludge is high to 5.84%, a toxicity test is taken on the sludge according to GB5085.3-2007 and the extraction content is 15.75mg/L, which surpasses the arsenic extraction standard [As]=5mg/L, the sludge is categorized as hazardous waste. If put outside without disposal, it would be very harmful to environments. Here we report an optimum protocol to extract arsenic; S2- alkaline liquor is utilized to treat the arsenic sludge. At 85?, 10L 7% S2- liquor is added into 1kg dried sludge and the resulting mixture is stirred for 120min at 250r/min, then separated by centrifugation and the compressed waste residue dried naturally. The average arsenic content is 1.40mg/L, lower than GB5085.3-2007 Standard and arsenic-free residue is consistent with GB18598-2001 Standard, which can be bury safely. The extracted arsenic is transferred into copper arsensite for use as addictive in copper electrolysis and the waste water can be recycle after calcium is removed.

Jan 1, 2014

By P. Knudsen, S. Rosenthal

INTRODUCTION In 2010, Montana Tech was gifted 65 acres of land immediately west of the campus. The parcel of land included an old silver mine called the Orphan Boy Mine. The Orphan Boy and its sister, Orphan Girl, were developed about1895 and operated until 1956. In addition to the gift of land, a significant industry gift was obtained to develop a first class training facility, which we call the Underground Mine Education Center (UMEC). The UMEC has been funded primarily by industry through donations of dollars, equipment, and supplies. The UMEC is a unique hands-on, educational environment for today’s students who are being trained to find, develop and process the worlds' natural resources. The center complements courses in mining engineering, geological engineering, environmental engineering, metallurgical engineering and occupational safety and health. It also serves as a as research facility utilized by students and faculty, and other organizations interested in doing research a hard rock underground mine. LOCATION The Orphan Boy and Orphan Girl Mine are located approximately 700 feet (ft.) apart and the Orphan Girl Mine is part of the World Museum of Mining. Underground they are connected on various levels and all levels below the 100 ft. level are currently flooded. The Orphan Boy mine was 804 ft. deep and Orphan Girl was 3200 ft. deep. The surface locations of the two mines and some of the underground workings on the 100 ft. level are shown on Figure 1 (2015). CONSTRUCTION Land ownership was gifted from BP/ARCO in 2010 and planning started immediately. In June of 2011, site development for the decline to the 100 ft. Level of the Orphan Boy began with a satisfactory portal site developed (Figure 2). We hoped to be able to start driving the decline in July. However, the portal was sited approximately 125 ft. away from a natural gas line that bisected the Montana Tech campus. While outside the right of way for the line, Northwestern Energy requested that no blasting be performed near the gas line until such time as the gas line was abandoned in the fall so decline development was put on hold. The gas line was officially abandoned in January of 2012.

Jan 1, 2019

By K. Huttu, A. van Wageningen

"The Kittilä underground mine in northern Finland is extracting one of the largest known gold deposits in Europe. Kittilä achieved commercial production on May 1, 2009, becoming Agnico Eagle’s first mine to open outside of Canada. The Kittilä orebodies were initially mined from two openpits – Suuri and Roura – and underground operations were added in October 2010. The pits were mined out in November 2012, so mining is now entirely underground in the Suuri and Roura deposits. Additional, small openpits will mine any remaining near-surface reserves in the future.The Kittilä Mine is located in the Lapland region of northern Finland, approximately 900 km (560 miles) north of Helsinki and 150 km (93 miles) north of the Arctic Circle. With a mine life estimated through 2034, Kittilä is Agnico’s longest-life mine.The mine’s proven and probable reserves contain 32 Mt (4.7 million oz) at 4.6 g/t (0.13 oz/ st) gold. Ore has been mined from underground since 2010. The original 3 kt/d (3,300 stpd) operation underwent an expansion project to increase the throughput capacity of the mill by 1 kt/d (1,100 stpd), starting by the end of 2014.The region around the Kittilä Mine is underlain by mafic volcanic and sedimentary rocks of the Kittilä Greenstone Belt oriented nearly vertical. This greenstone belt is similar to those hosting Agnico Eagle’s Canadian deposits in Quebec’s Abitibi region and Nunavut. At the contact point between ironrich and magnesium-rich rocks lies a 100- to 200- m (330- to 660-ft) thick structural zone known as the Suurikuusikko Trend. This trend hosts the Kittilä deposit, where multiple mineralized zones have been traced over a strike length of more than 25 km (15 miles).Most of Agnico Eagle’s work has focused on a 4.5-km (2-mile) segment of the Suurikuusikko Trend that hosts the five main zones of the known gold reserves and resources. From south to north they are: Ketola, Etela, Suuri, Roura and Rimpi.The ore at the Kittilä Mine is refractory, making gold extraction relatively difficult because the gold is generally locked inside the two main sulfide minerals – arsenopyrite and arsenic-rich pyrite. Only about 4 percent is very fine-grained “free gold” (not locked in sulfide grains) and easier to extract. Most of this free gold is found in the outer, oxidized or eroded sections of the ore."

Jan 1, 2015

By J. J. Webb

At Kerr-McGee's Galatia Mine in southern Illinois, the need for safe and efficient longwall moves prompted a detailed planning effort. Galatia Mine operates two longwalls on separate coal seams with different geologic conditions. An overview of the longwall move planning as related to manpower training, roof control, ventilation, transportation, equipment recovery and setup will be discussed. The impressive safety record achieved during each of the longwall moves at Galatia Mine verifies that health and safety planning does play a major role.

Jan 1, 1994

By Hsi-keng Hu

"This paper deals with the flotability of stibnite and summarizes the major experiences and technological innovations of some typical practices of antimony sulfide ores in China. Experiences of cyanide-free and -less flotation of complex antimony sulfide ores and the application of the heavy media process to the preconcentration are described.Performance improvements obtained by innovations in operating techniques are also outlined and discussed. Technical innovations involve: (1) ramification roughing and differential-rate cleaning of stibnite-arsanopyrite ore; (2) the application of the new flotation reagent system; (3) process of separation flotation of Sb-Hg bulk concentrate; (4) extraction of gold from Au-Sb bulk concentrate; (5) flotation recovery of coarse stibnite particles.IntroductionChina is rich in natural resources of antimony and is one of the major antimony producers in the world. During the past several decades, a lot of research works have been done and many experiences in milling practices were gained, some of which are summarized briefly as follows.I. Heavy Media separation of Antimony sulfide Ore at Xikuangshan Hill, Hunan province (1)HMS as a technique of preconcentration of antimony ore has been performed more than ten years in China with good results.1. Ore characteristics The antimony ore of Xikuangshan belongs to the epithermal- metasomatic-filled doposit of antimony sulfide. Major minerals are stibnite (92.1%), antimony oxides (7.9%) and a small amount of pyrite and pyrrhotite; the gangue minerals are quartz, silicic limestone, calcite, hydrous kaolin, sericite, barite and others. The specific gravity of the ore is 2.8 and the specific gravity of stibnite and gangue are 4.6 and 2.654, respectively."

Jan 1, 1988

By G. X. Du

Reaction kinetics of serpentine and hydrochloric acid is theoretical basis for optimizing reaction process conditions of serpentine and hydrochloric acid. Kinetics of serpentine and hydrochloric acid was studied in this paper. The results indicated that apparent reaction order to hydrochloric acid was two and reaction kinetic equation could be expressed as: 2HClHCl,ddtckct-=·. The diffusion rates of hydrogen ions in liquid film on surface of serpentine particle and in amorphous silica layer generated in the reaction and chemical reaction velocity during the reaction had important effects on to-tal reaction velocity. And chemical reaction velocity had the most significant influence. The relation of conversion rate of magnesia xMgO with reaction time could be expressed as: 1(1)xkt--=·.

Jan 1, 2014

By F. Charette

Instrumentation has been developed that can monitor the strain applied to a D-Bolt up to 7.5% elongation. The technology far exceeds the limit for foil resistance strain gauges. In the laboratory the instrumentation has provided insight into the fundamental behaviour of the D-Bolt following yield. Currently the instrumentation is undergoing field trials at a number of Canadian Mines. Discussion on field results is provided with regards to significance, reliability and temperature effects.

Aug 1, 2013

By Junji Shibata

Extraction behavior of Ti(IV) and other metal ions, such as Fe(III), Fe(II), Cu(II), Zn(I1) and Co(I1) from acidic solutions like sulphuric acid and hydrochloric acid was studied in order to recover titanium from the waste solution in Ti02 production. Extractant used was tri-alkyl phosphine oxide whose trade name was Cyanex 923. Then, a study was made of the idea of simulating a countercurrent multistage extraction system, using the results of batch extraction. The simulation was camed out on extraction and saipping behavior for a Ti(1V)-H$O,-Cyanex 923 system. From the simulation result., the optimum operating condition of the system was considered.

Jan 1, 1994

By M. G. Premo

The McKinley Mine is located in the northwest New Mexico, in McKinley County, approximately 25 miles from Gallup. The mine is operated by The Pittsburg & Midway Coal Mining Co. (P&M), a wholly owned subsidiary of the Chevron Corporation. P&M is headquartered in Englewood, Colorado. Since the McKinley Mine began operations in 1962 a total of 83,391,000 metric tons of coal have been sold through 1990. The 1991 production was approximately 5.000.000 metric tons. The mine operations are contained on a 109.000 square kilometers lease area of which 44.000 square kilometers are on the Navajo Nation. The present customer base consists of four utilities and one industrial account, all of which are located in Arizona. The utility customers are the Arizona Public Service Co. Cholla Station at Joseph City, The Salt River Project. Coronado Generating Station near Joseph City, and The Tucson Electric Company, Irvington Generating Station in Tucson. The industrial customer is the Stone Container Corporation, Snowflake Paper Mill.

Jan 1, 1992

By Y. Fukunaka, M. Niinae, E. Kusaka, T. Kuzuya, R. Ishii

"Samarium oxalattr particles was precipitated in oxalic acid aqueous solution from samarium-loaded D2EHPA solution emulsified with a conventional impeller. The calculated fractional precipitation of samarium oxalate was reasonably compared with the value determined by chemical analysis. Morphological variation of oxalate precipitate particles was then examined with H2C2O4 concentration in aqueous solution, Sm(III) and D2EHPA concentrations in organic phase. The needle-like precipitate was identified as Sm2(C2O4)3 10H2O by XRD. Precipitates obtained at higher H2C2O4· or Sm(III) concentration greatly decreased the length of major axis of precipitate, while those at higher D2EHPA concentration increased it. The oxalate was further precipitated under ultrasonic irradiation. However, the morphological variation caused by theses processing variables was not so evident under ultrasonic irradiation as in an impeller or shaking mixer.IntroductionThe materials processing of the rare earth elements must be reviewed from the scope of industrial ecology, since they have the potential applications of magnetic materials as well as secondary battery in developing programs of the electric vehicle. The technological trend to develop the electric vehicle may greatly influence the concept of materials processing, since the global· environmental problem must accommodate with the sustainable development for mankind. The recycle design must be a key issue in the materials science and engineering.Solvent extraction provides a unique separation technology -in this sense. Doyle (1)(2) reported the integrating solvent extraction with processing of advanced ceramic materials, whose chemical composition and microstructure must be precisely controlled. In her paper, the higher productivity inherent to the present process superior to hydrolyzing metal alkoxides was emphasized. Oxalic acid has been used as precipitant for rare earth purification process, since rare earth oxalate has a very small solubility in water and can be easily decomposed to oxide. It is thus suitable for precipitation stripping agent in cationic exchange type extracting system (i.e. D2EHPA, VA-10, PC-88A and so on)."

Jan 1, 2000

By William Nicoll

Those who use electric detonators in firing blasts will be interested in a new electrical testing instrument known as the ‘Blasters’ Friend’, recently devised by the New York Blasting Supply Co. of New York. Owing to the necessarily delicate construction of the platinum wire bridge in the shell of a detonator, it frequently happens that it becomes broken or disconnected; thus destroying the circuit and rendering the detonator worthless. In many cases, misfires and premature explosions are caused by defective detonators. Heretofore, to detect the deficiencies of a detonator before using has been an impossibility, owing to the absence of a testing instrument adapted to the purpose.

Jan 1, 2010

By Frank A. Vonesh

In order to reduce the amount of visible, airborne emissions in the Metals Industry, a new Industrial Gas Technology was developed by Air Liquide. This patented technique is called ALECT?, Air Liquide Emission Control Technology. Demonstrations have been conducted for many cutting and lancing operations as well as for hot metal transfer from vessel to vessel. Fume reductions of 90% and greater have been achieved in actual practice. Air Liquide continues to improve the process and the associated control equipment.

Jan 1, 1994

By J. C. Franklin

The Bureau of Mines substantially reduced shale degradation in a coal mine by two spray coat applications of a water-base epoxy sealant. More than 12,700 square feet of passageways were treated, and in 18 months only one failure occurred. This failure was due to improper spray application, Material costs averaged 13 cents per square foot, and labor costs were 7 cents per square foot. Labor included moving all materials into the mine, the setup time for each of the areas coated, and application of coatings.

Jan 1, 1977

By John S. Anderson

The need for fuels and minerals in this country is estimated to double, triple, or even quadruple by the end of the present century. Even assuming more recycling of scrap metals and some priority allocation of energy, as has been done, for instance in war time, the projected increase in the nation's population and ever-increasing wants of that population will require vastly more minerals than are now being produced. Since mineral ores are being mined at lower grades, and since all minerals, including fuels, are having to be mined from deeper deposits, the amount of surface land to be disturbed will, inevitably, be increased. We cannot depend on foreign sources to supply all the extra requirements, since the non-U.S. population is increasing, in most cases, faster than our own. Furthermore, starting from a lower base, their mineral needs may accelerate more rapidly than ours. Restrictions on exports may be applied in foreign countries, if it appears that remaining reserves are not sufficient to fill the national needs. In vice; of the opposition which the mineral industry is receiving, as has been well described at these sessions and elsewhere, what can we, as mineral producers, anticipate as regards our ability to continue to operate, to sway nothing of expanding production? Although not minimizing the problems involved, it seems obvious that, except under emergency conditions, the country cannot tolerate a reduction in the available

Jan 1, 1971

By S. Gaydardzhiev

Laboratory batch tests having preliminary and orientation character aiming at improvement of the molybdenum flotation at Ellatzite copper processing plant in Bulgaria have been conducted. The following technological parameters have been screened to study their influence on the grade and recovery of copper and molybdenum during the rougher flotation stage: flotation pulp density, pH, addition of secondary collector and replacement of MIBC by pine oil as a frother. The results have shown that slightly better grade/recovery figures could be obtained for both copper and molybdenum at lower flotation pulp densities. The addition of kerosene has improved the recovery of molybdenum however, on the expense of that of copper. The effects from pH variation and the replacement of MIBC by pine oil as a frother have been almost negligible.

Sep 1, 2012

By Winmill T. F.

Paper presented at the at the Institution of Mining Engineers' general meeting held in London on 8th June 1916: In a previous paper it has been shown that the rate of absorption of oxygen by coal is neither directly proportional to the surface area of the coal exposed nor to the percentage of oxygen in the air. Further experiments are now described supporting this conclusion

Dec 1, 1916

By Xiao Long, Ting Wu, Lilong Zhu, Qian Wang, Shengping He

"During the continuous casting of peritectic steel slabs, mould fluxes with high crystallization capacity are usually chosen for improving slab surface quality. However, the lubrication condition of casting shell also could be deteriorated. Since precipitation of crystals within liquid slag film can change the composition and property of liquid slag over solid-liquid slag film interface region, its impacts on continuous casting process also are not clear. In order to clear this phenomenon, an experiment method was put forward, and mould fluxes for peritectic steel slabs continuous casting were selected and examined. The results reveal that after crystals have been separated, the crystallization capacity of leftover liquid slag increased with different levels, which could deteriorate the lubrication condition of casting shell and cause a series of problems. Thereby, mould fluxes with high crystallization capacity at beginning for heat transfer control and then weaker after crystallization should be considered in the future.IntroductionIn the continuous casting of peritectic steel slabs, contradiction between heat transfer control and slab shell lubrication by mould fluxes has been treated as a key problem for maintaining a smooth manufacturing process [ 1]. Strong and uneven horizontal heat flux over the meniscus region will cause uneven solidification of casting shell, especially for peritectic steel slab with enormous volume change caused by phase transition. All of those could cause surface defects like longitudinal crack [2-4]."

Jan 1, 2013

By R. J. Fruehan

Oxygen steelmaking (OSM) is not only the dominant steelmaking process but defines the structure of the industry. There are a number of myths regarding the future of OSM, which are false. These myths include that the EAF will become the dominant process in the near future, it is less costly to produce steel in an EAF and OSM is a mature technology and no new developments are occurring. These myths are shown to be false. Selected new developments are discussed such as post combustion, recycling of waste oxides, slag splashing and sensors.

Jan 1, 2004

By V. Ramachandran

Under the Resource Conservation and Recovery ACT (RCRA), generators of listed or characteristic hazardous wastes must find satisfactory means for disposal. of wastes. Initially, for many this meant landfills and deep-well injection. Until recently, mining and metallurgical by-products have largely been exempt from RCRA, but now are coming under its jurisdiction. With the increasing closures of landfills, companies in the U.S. such as electroplaters, miners, metallurgical plants and others are turning to recycling as an alternative to treat their wastes. While the cost of recycling has been challenging, the long-term economics prove attractive because recycling interrupts the cradle- to-grave responsibility for the waste generator. The present paper describes the recycling of hazardous wastes at ENCYCLE/TEXAS. Encycle extracts marketable metals from metal-bearing sludges and wastewater using hydrometallurgical processes borrowed from the mining and metallurgical industry.

Jan 1, 1994

By K. Fair

Using an agitated column 203 mm (8") diameter by 1829 mm (72") tall with independent agitation units for the gas dispersion zone and the collection zones, respectively, permitted the independent evaluation of the attachment and the detachment mechanisms for the chalcopyrite/ silica system. Three particle size fractions were used in this study, i.e. coarse (+75 µ m), intermediate (-75 µ m + 10 µ m) and fines (-10 µ m). The optimum selection of the two agitation zones for the three particle size fractions were determined as a function of grade, recovery, residence time and air superficial gas velocity.

Jan 1, 1990