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By T. Y. Yan

A method has been developed to remove calcite from the leaching circuit in the uranium in situ leaching system. The process involves injecting the leachate and a pH control agent tangentially into an inverted cone reactor containing calcite seed catalyst. The leachate can be treated at high throughput to obtain clear effluent containing 5 ppm or lower Ca. Both lime and ammonia are effective pH control agents and consumed according to stoichiometry.

Jan 1, 1983

By William Petruk

Image analysis studies were performed on mill products from pilot-plant and laboratory tests that had been conducted to determine the effect of grinding media on the selective flotation of two zinc-lead-copper ores. It was found that, when the ores had been ground to the same degree of fineness with flint pebbles, ceramic pebbles or ore fragments (autogenous grinding) as with steel balls, there generally was increased sphalerite, chalcopyrite and galena liberation in the flotation feeds, depending on the textures of the minerals. The increased sphalerite liberation fully accounted for the improved zinc recoveries that were obtained when steel balls were replaced by either pebbles or ore fragments. The increased chalcopyrite and galena liberation accounted for part of the changed technical efficiency of concentration, but other factors, probably changes in oxidation and reduction of iron and in consumption of oxygen, also contributed.

Jan 1, 1977

By Pedro Alca F

El presente texto refiere el análisis ecónomico en la industria minera privada a través de la estadística financiera como método de medición y gestión empresarial. Para ello, se evaluaron 33 empresas representativas de la mediana minería durante el período de 1975-1979, obteniendo 12 índices standars de tipo financiero y económico para así preveer mediante una administración financiera, el objetivo económico de la empresa. En este sentido, se busca hallar no solo los índices standars en la industria minera, a partir de los datos generados por la correlación de principales cifras de los balances generales, estado de pérdidas y ganancias de los 5 últimos años de operación, sino que se realiza el análisis en conjunto de toda la compañía.

Oct 14, 1980

By Steve Axen

In situ mining is now considered an alternative mining method for some ore bodies. The in situ operation consists of a well field designed from reservoir properties and geological information; the wells for such a field are then drilled, cased, and cemented, using good designs and practices to eliminate future problems. Injection and production (recovery) systems are required to be corrosion resistant. Hand in hand with the mining operation is the metal extraction plant, the entire operation offering an environmentally acceptable method for metal recovery. Great opportunity exists in this field for mineral engineers; presently, they must borrow knowledge from other fields, since the schools have not yet addressed this specialty.

Jan 1, 1979

By R. Sharon

Barrick Goldstrike Mines, Inc. Betze-Post open pit operations, located in northeastern Nevada, have experienced slope instability attributed to the presence of generally weak rock mass conditions, local adverse structural geology and perched groundwater. Ground movements are monitored with acombination of optical survey, extensometers, inclinometers, and time domain reflectometry (TDR).The slope monitoring system at Goldstrike includes two robotics theodolites, which provide real-time coverage for all highwall areas. Survey instruments are housed in specially designed climate controlled shelters in locations where all slopes can be observed. A “remote” computer housed with each theodolite collects data. The “base” computer, located in the mine offices, is used to access data from the remote computers via radio modem.

Jan 1, 2000

By Xuan Cheng

The electrochemistry of sulfide mineral flotation is reviewed with particular emphasis on galvanic interaction among minerals and grinding media, and its relevance to flotation of complex sulfide ores is discussed. Surface alteration due to galvanic interactions among chalcopyrite, pyrrhotite and mild steel is analyzed in terms of voltammetric and chronoamperometric studies on individual minerals and through galvanic current measurements in 2- and 3- electrode combinations. The results are related to laboratory flotation behaviors of chalcopyrite-pyrrhotite mixtures simulating copper-nickel bearing Duluth gabbro.

Jan 1, 1993

By C. T. Baroch

The purpose of this report is to describe the design features and techniques used in operating a plant capable of producing about 1,500 pounds of titanium metal per day. The process used was based on the reduction of titanium tetrachloride with magnesium, a modification of what is generally known and spoken of as the Kroll process. Sponge metal crushed to melter's specifications was the end product of the operation as conducted. The report is divided into sections covering general plant layout and the major unit operations. These, in turn, are each divided into discussions of the equipment, operating procedures, and typical results. Descriptions are given in more detail than is generally expected of a technical report. During 1953 and 1954 over 130 engineers and businessmen, officially representing some 80 industrial, chemical, end engineering firms, visited the operating plant, and their questions, which indicated a serious interest in details, have served as a guide for the material contained in this report.

Jan 1, 1955

By Samuel S. M. Chan

The objective of this project was to collect information applicable to the design of ground support systems in deep mines to include in-situ rock deformations, deformation-modulus, stresses, and geology and laboratory physical properties. All data collected was to be integrated and evaluated using a finite-elements computer code. In addition, considerable professional "cross pollenization" was anticipated from the association of University and SMRC personnel. Scope of Investigation Before a ground supporting system can be evaluated, the loading conditions existing in the region of investigation, strength, deformation characteristics, as well as other engineering properties of the rock structure immediately surrounding the openings, together with the pertinent geological information, must be obtained and analyzed. It was for this reason the following items were included in this research project: (1) The selection of a suitable area for the investigation. (2) The mapping of the important geological features of the area of investigation. (3) The measurement of in-situ deformation of rock masses immediately surrounding an underground opening of the area of investigation. (4) The determination of ground stresses. (5) The obtaining of in-situ modulus of deformation of the rock masses. (6) The testing of useful engineering properties of

Jan 1, 1972

By George W. Friesen

This paper presents the historical trend and de- fines the causes of drilling cost escalation in the Gulf of Mexico during the 1970's. The three major components of escalation are: 1) inflation, 2) supply-demand imbalance (demand pull) and 3) decreases in drilling efficiency. The decade was divided into three periods. During each period one component of escalation was responsible for most of the rise in costs. From 1970 through 1973 only inflation pushed costs upward. During 1974 and 1975 a supply- demand imbalance caused most of the escalation. Since 1975, decreases in drilling efficiency have produced the major component of escalation. During any one year or period of years, the sum of the three components will give the total escalation rate. The reasons why different components contribute more toward escalation during certain years than others are shown by following the timing of oil and gas price increases, the overall quality of the acreage offered each year in offshore lease sales and the resulting drilling activity.

Jan 1, 1982

By Lucía Neme, Camila Cabrera, Consuelo García

La creciente preocupación mundial por el cambio climático y los esfuerzos para lograr el desarrollo sostenible requieren mayores cantidades de materiales de transición energética (ETM) cada año, entre ellos, el litio. Sin embargo, quienes viven en los territorios donde se extrae este mineral se ven doblemente expuestos, tanto a los riesgos provocados por el cambio climático como a los que produce la creciente e intensa actividad minera. Este trabajo busca identificar y explorar los riesgos sociales percibidos por las diferentes partes interesadas en la extracción de litio en la región del Triángulo del Litio (el Triángulo), y cómo estos riesgos son gestionados por ellos.

Sep 29, 2023

By B. P. von der Heyden, T. Blenkinsop, A. Mamuse

Zimbabwe hosts a varied array of coloured gemstones. With the exception of emerald deposits and several world-class pegmatites, few of the gemstone occurrences have received detailed attention from the scientific or mineral exploration communities. In the present contribution we summarize the status of knowledge of the gemstone deposits and occurrences in Zimbabwe, paying particular attention to the geological settings in which they were formed. Synthesis of this regional geological approach reveals that there may be significant exploration potential for further gemstone occurrences, particularly in the extensive pegmatite fields and in Al-enriched orogenic belts that have undergone greenschist to granulite facies metamorphism. Further socio-economic and developmental initiatives will aid in optimizing the value generation from this important sub-sector.

Feb 12, 2024

By Rodney L. Stone

As part of an overall laboratory and plant test program to determine mixing and other techniques relating to the more economic use of bentonite as an iron ore pellet binder, a settling test was developed for measuring the bentonite content within a pellet or within a batch of pellets. Between pellet batches, each containing a different level of bentonite, the dry fracture load is directly proportional to the bentonite content between pellets of the same batch, however, the fracture load is inversely proportional to the bentonite level; this is explained by a negative correlation between a pellet's size and its bentonite content and the fact that larger pellets can withstand a higher fracture load than the smaller.

Jan 1, 1968

By Peter J. Szabo

In 1980, a caravan of representatives of Japanese trading companies debarked on the shores of the United States bearing gifts of watches, electronic games, and radios. In early 1983, we find in a parking lot of a major U.S. coal company, a haggard general manager of marketing returning to the Orient with a box under his arm of trinkets of his own; cross pens with company logos, alarm clocks, etc. The tables have turned, but our fellow sitting in a jet plane over the Pacific Ocean had only to heed the warning of the famous 19th Century poet well familiar with the ways of the Far East. Kipling said; "And the End of the Fight is a tombstone white and with the name of the late deceased, And the epitaph drear, a fool lies here who tried to hustle the East."

Jan 1, 1984

By R. F. Winkle

Shortly after World War II, considerable impetus was given to use of truck haulage in open pit mines by the manufacture of large off-highway trucks. Mine management was quick to utilize this more flexible approach to open pit operation and in the ensuing years much time and energy has been spent to improve the basic concept. Dramatic progress has been made in drilling, blasting, loading and hauling with much emphasis placed on equipment improvement. In general, haul roads in open pit mines and quarries have received rather perfunctory treatment in studies of surface mining operations. Their importance to the successful pit operation requires more than a brief sentence saying, "Good haul roads must be maintained." Haulage costs account for approximately one-third of total mining costs including general costs and about 90 percent of the total loading-haulage cycle time is consumed in travel, hence, good haul road planning, construction and maintenance are mandatory for a viable operation.

Jan 1, 1976

By J. P. Matoney

The operation of a modern coal preparation plant, particularly in western Canada, is a very complex task. Most western Canadian operations are processing two or more, sometimes up to ten, different seams through the same plant. This requires a sophisticated multi-circuit plant that needs close operational control. Add the soft nature and large amounts of natural fines of western Canadian coal and you have a formidable cleaning task. To assist in the operation, programmable controllers and sophisticated control concepts are being more widely used. Two of the newest coal preparation plants in Canada have been designed by Raymond Kaiser Engineers Inc. and its Canadian subsidiary, Phillips Barratt Kaiser Engineering, Ltd. The use of programmable controllers and control systems will be illustrated by showing their application in a "typical" western Canadian coal plant. This example will cover flowsheet design, control concept systems application, and possible future uses.

Jan 1, 1983

By M. O?Driscoll

The tide has turned. Developments in China that have continued to unfold over the last four years or so have now reached a point where the supply market dynamics of certain industrial minerals have changed significantly. No more is this sea change better exemplified than by the supply market for magnesite, and in particular, its processed derivative grades of dead burned magnesia (DBM), caustic calcined magnesia (CCM), and fused magnesia (FM). But what has compounded the barrage of influencing factors impacting this sector, which include the widespread effects of energy and freight cost increases, has been rising demand from certain end use markets. Clearly, the magnesia market is experiencing bittersweet conditions. But those western producers which have monitored and responded to this market transformation, stand to taste success in the near and medium future. REVOLUTION IN WORLD SUPPLY STATUS In essence, while China, as host to a wealth of magnesite resources in Liaoning province, remains a huge producer of magnesia, its supply dominance on the global magnesia market has been considerably weakened. In future, it will mainly aim to supply domestic, and to some extent east Asian markets. Magnesia consumers outside China are now scrabbling for alternative, ?western? sources of supply. At the same time, magnesia producers outside China that weathered the storm of low cost Chinese DBM and FM imports flooding their regional markets for the last 20 years (and many did not), are busy investing in production capacity increases to meet not just demand from falling Chinese supply, but also demand from end use markets which is picking up. And it is not just a matter of expanding capacity of existing magnesia product lines. In the face of plentiful lower cost DBM and FM substitutes from China over the last couple of decades, many western magnesia producers started to switch their focus to the non-refractory markets (eg. environmental, specialities) which promised lucrative opportunities (and still do) and crucially, a lessening of sales revenue dependence on the DBM refractories market. Now we have the likes of Baymag (Canada), Bommag (Serbia/Turkey), and Kumas (Turkey) not only expanding capacities but seriously considering diversifying into DBM and FM production. Perhaps DSP (Israel), having ceased its famous high purity DBM activity as recently as 2005, might even reconsider a return to the ?other side?. But it?s not all DBM and FM. The CCM and specialities markets are also demanding a response, and so Baymag, DSP, Martin Marietta (USA), Premier Chemicals (USA), Qmag (Australia), MGR (Spain), and Magnifin (Austria) are also stepping up to the market on the non-refractory side. From most accounts, the situation with regard to Chinese supply has been described as one of turmoil, with prices rising, leading to improving opportunities for western producers. The majors are conducting huge expansion programmes, such as Qmag, Magnezit (Russia), and the new look Magnesita (Brazil). Even smaller players such as Causmag (Australia) and Dalmia (India) are looking to increase production. In short, the western magnesia supply sector is witnessing a landmark event in capacity investment and market share penetration as China?s previously dominant role begins to weaken (for a review of western capacity expansions see Industrial Minerals, September 2008, p.28). MERGER & ACQUISITION ACTIVITY Another response of course has been a raft of mergers and acquisitions in order to secure resources and supply outside China. These have included private equity groups taking over Magnesita and Qmag; Imerys entering the FM business through UCM; Peñoles further consolidating the electrical grade FM market by acquiring Minco; Martin Marietta acquiring Morton Salt?s Specialty Magnesia Group; Bomex entering the market through Calmag (now Bommag); LWB acquiring Magnesita; and Magnezit?s pursuit of Slovakian magnesia, with Slovmag aboard while currently wooing SMZ. Interestingly, RHI has gone ?the other way?, and has invested in a state of the art joint venture operation at Dashiqiao, Liaoning, with which it aims to secure high quality feedstock for its Chinese refractory plants. Tata Refractories Ltd has announced intentions to follow suit, and other majors, such as Qmag are known to be interested in seeking options. Naturally, there is now renewed interest from several parties in the idled 50,000 tpa DBM/10,000 CCM Jormag facility, Jordan, and the commercially undeveloped Zhargat project, Saudi Arabia. Elsewhere, there will no doubt be suitors for stakes in SMZ, in Slovakia, and Magnohrom, in Serbia, whose respective ownerships are on the block. THE ?CHINA FACTOR? The ?China factor? has been key to magnesia?s market change, and has significantly influenced prices and availability of material to global markets. Resources & production China hosts the largest share of the world?s magnesite deposits, accounting for 26% or 3,319m. tonnes of predominantly sparry magnesite (followed by North Korea, 24%, and Russia, 22%; Wilson 2008). China accounts for 44% of total world magnesite mined (19m. tonnes in 2007) and 50% of the total world magnesia produced (8.2m. tonnes CCM, DBM, FM; Wilson 2008). Russia follows China at 13% of magnesia supply, illustrating China?s dominance of magnesia production. Apart from one producer in Shandong province, central eastern China, the country?s magnesite resources and production are concentrated around the cities of Haicheng and Dashiqiao in Liaoning province, north-east China. Although there are also producers in the Xiuyan district of south-east Liaoning, the Haicheng-Dashiqiao Magnesite Belt hosts the majority of producers. In total these may number 200-300 of large,

Jan 1, 2009

By Heine Kenworthy

In 1930 the Shenandoah-Dives Mining Co. near Silverton, Colo., put into operation a newly erected, 300-ton selective flotation plant to mill complex ores from its nearby mine. The operation was a steady producer and was enlarged to treat 600 to 800 tons a day. In 1942 the company opened and started milling an area in the mine containing semioxidized ore. The valuable mineral. Content of this ore was considerably higher than in the straight sulfide ore previously handled alone. The mixture of clean sulfide and semi-oxidized ore was difficult to treat; consequently tailing losses, especially with respect to lead, were high. A. few years later, in order to study the possibilities, of obtaining higher recoveries by a modification of the mill flow sheet, a 1,200-pound sample of mill feed, taken over a period of several days by the company, was submitted to the Mississippi Valley Experiment Station for testing. Although this sample proved to contain more than twice as much lead as the average yearly mill feed, the same problem of recovering the oxidized values were present.

Jan 1, 1948

By Laurence G. Trudell

A geologic framework for interpreting stratigraphic and geographic variations of the Green River Formation in the Piceance Creek Basin is developed from lithologic data accumulated by the Bureau of Mines from oil-shale coreholes. From detailed Bureau of Mines descriptions of samples from nine coreholes and supplementary lithologic data from seven additional sampled sections, three cross sections were constructed along lines transecting the basin. Plotted as lithologic columns with corresponding oil yields and resistivity logs, the sampled sections are correlated on a time-stratigraphic basis. Distribution and correlation of nahcolite and halite zones are shown, and the approximate base of leaching of these saline minerals is indicated. General lithologic characteristics of members and zones are discussed and interpreted. Large-scale lithologic logs illustrate the nine Bureau of Mines core descriptions, and the complete description of Bureau of Mines-Atomic Energy Commission Colorado Corehole No. 1 is included in an appendix. The time-correlated cross sections provide a necessary framework for understanding the depositional history of the Green River Formation and will facilitate evaluation of oil shale and other mineral resources in the Piceance Creek Basin.

Jan 1, 1970

By F. Heivilin

Little did I know, in 1977, that when the A. P. Green Refractories Raw Material Manager showed me 5-6 burlap bags with samples of calcined high alumina bauxite in their testing lab that this was the start of China moving to be the number one user and producer of calcined refractory bauxite. According to Ted Dickson in his August 2008 Industrial Minerals article China produced about 4 million tons of calcined bauxite in 2007 using 2 million tons themselves. They imposed an export limitation of 970,000 tons in 2007 and 940,000 tons in 2008. A 10% growth will take up the difference between exports and production in 4 years. Two of these years are gone. It will take only 4 more years to eliminate the export quota in home use. Then they will be importing unless they increase production. Guyana was exporting over a half million tons in 1975 and sold less than 70,000 tons in 2002. Basai Metals Group bought Guyana?s deposits and is rose to 250,000 tons in 2007 and expects to produce 280,000 tons in 2008. PRICES According to the USGS Prices dropped from $172/per ton for Guyana calcines in 1980 just after the start of Chinese production to $122 in 1985. Guyana prices averaged around $120/ton from 1985 to 2005. China?s price dropped as low as $45/ton in 1995 undercutting Guyana and making it virtually impossible for anyone to get into the market. The price suddenly escalated to $550/ton FOB China in the summer of 2008 when China actually cut its exports in half. The price dropped in the fall as orders dropped. This is a four to five fold price increase. Is this a shortage of bauxite or a monopoly? Australia dropped out of the market in 2008 and Surinam, controlled by Alcoa, is not participating right now. Will these two come back in to make up the difference? Will the price hold up so they can make a profit? [ ] The low prices have undoubtedly affected the prices of the 60 and 79% alumina bauxite which can hold down the quantity of 80% plus calcined refractory needed in the world market. China is starting to upgrade lower quality bauxite up to 90% alumina. With high prices kaolin alteration to high alumina comes into play. The calcined bauxite is also used for proponents, Brown fused alumina, and abrasive grades which compete with Refractories. These and the tightness of supplies needed for metallurgical will hold prices up. TONNAGE China is the number one supplier and consumer of high alumina calcined bauxite in the world. Basai Metals Group Guyana (BMGG) is owned and controlled by Basai Minerals Group of China. This appears to be the second largest supplier. Australia has dropped production and Brazil is just starting to expand. It appears China is going to replace some of exports caused by the Export License 940,000 ton maximum in 2008 by raising Guyana?s (BMGG) production of calcined refractory grade bauxite. Companies exceeded restriction in 2007. Fines have been imposed for 2008. In August 2008 they appear on line to meet the 2008 quota. After August prices have dropped off as orders dropped due to the recession. Guyana was the largest producer in 1975 with 769,000 tons which decreased to less than 79,000 tons in 2002. The U. S. is a small part of the world production. I have used the United States charts to represent world imports because I have little data on what other countries import and pay FOB for their bauxite. China started exporting calcined 80% plus refractory bauxite to the United States in 1979 with 24,000 tons. By 1985 they were the number one importer with 169,000 tons. Guyana who had been number one in shipments to the United States gradually decreased to 36,000 tons in 2006. Guyana has been purchased by China BMGG and will increase there production to over 200,000 tons in 2009. Australia shut down production in 2008 and Surinam has elected to not send any Calcined bauxite to the United States. Imports to the United States from 1978 to present are as follows: [ ] Refractories are important because they affect 96% of the GNP. During the cold war we had stockpiles of 80% refractory grade bauxite

Jan 1, 2009

By S M. Stewart

Building and Maintaining Community Relationships   In mining terms, the town of Waihi is distinctive with the Martha mine situated right in the heart of the town. MarthaÆs central location and other mining activity nearby means there is an increased community focus on the happenings at the mine and the effects and impacts of mining. While WaihiÆs proximity to the mine is unique, all mines have a community context that they operate within.   Issues of proximity simply heighten awareness and emphasise the need for building and maintaining good community relationships. In the three years we have been working alongside the Waihi community, we have worked together with concerned and supportive residents, representatives of Newmont Waihi Gold and representatives of Hauraki District Council, to develop a collaborative framework for addressing the economic, social, environmental, cultural and spiritual wellbeing of the people of Waihi. This could not have occurred without the genuine commitment of all participants.   This collaborative focus has resulted in some tangible progress in Waihi which, in part, stems from people taking an interest in the town because the town is taking an interest in itself. As we have worked and learned within the process of building and maintaining a collaborative and sustainable community environment, we have tried to adhere to a philosophy and a set of basic principles. We believe that this approach, combined with a teachable skill set, helped to create the opportunity to develop a truly collaborative community environment which continues to grow. Our paper will describe this philosophy, these principles and the skill set that we have applied.   The application of the process in Waihi has resulted in a series of outcomes unique to Waihi. These outcomes include formation of the Waihi Community Vision committee, the Vision Waihi Trust and the subgroups set up to further the interests of particular groups, for the collective benefit of all the community.   Based on our experience of other situations, and on the way the Waihi process has developed, we believe that the identified principles and skills can be transported and used in other cultures and contexts. While the resultant outcomes may differ, the underlying principles will still apply. Progress will come from creating a sustainable environment within which the community (including residents, industry and regulatory authority) can determine its own internal relationships and the vibrant growing sense it has of itself.

Jan 1, 2006