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By M. M. Gilkey

This report on water requirements for the New Mexico mineral industry includes data on industrial operations closely related to mineral production. It contains general information concerning public water supplies at five principal cities and a short discussion of water needs for agriculture. Background data are presented regarding the geography, hydrography, and water laws of New Mexico, as well as precipitatton and evaporation characteristics of the State. Most of the information on source, quantity, distribution, cost, and treatment of water was obtained in interviews with company representatives. Water systems at 46 operations are illustrated by schematic waterflow diagrams. The study revealed that the New Mexico mineral industry in 1962 used about 16 billion gallons of new water and reused 152 billion gallons, a total usage of 168 billion gallons. Consumption amounted to 7.6 billion gallons. Of the 16 billion gallons of new water, 11.9 billion gallons was "self- supplied" from ground water sources, and 2.6 billion gallons was self supplied from surface sources. Approximately 1.5 billion gallons was purchased. Some of the water from company-owned wells is piped as far as 30 miles. Reported costs of the self-supplied new water range from 1 to 20 cents per 1,000 gallons and average 8 cents per 1,000 gallons for power and maintenance. Inadequacy of the supply of new water at many operations necessitates large-scale recirculation. Reported costs for recirculating water (power and maintenance) average 1.8 cents per 1,000 gallons. For the entire New Mexico mineral industry in 1962, the value of product was $42 per 1,000 gallons of new water intake and $88 per 1,000 gallons consumed. Analyses of 40 water samples, listed in the appendix, show the wide range in water quality at plants throughout the State. Projection of the 1962 water requirements of the mineral industry indicate that the total demand for new water will increase from the 16 billion gallons used in 1962 to 24 billion gallons in 1980, a 50 percent increase; and to 36 billion gallons in 2000, which is 125 percent more than the 1962 intake of new water.

Jan 1, 1965

By B Lumsden

During periods of high metal prices and strong metal demand tailings retreatment can be economic. Most tailings retreatment operations are technically challenging, low margin operations, because the easily recovered mineral has already been removed, therefore, process improvements can potentially yield large economic benefits. The Hellyer tailings dam was owned by Intec Ltd and contained 10.9 million tonnes grading 2.8 per cent zinc, 3.0 per cent lead, 88 g/t of silver, 0.16 per cent copper and 2.6 g/t gold. In November 2006 the Polymetals Group, as operator, restarted the Hellyer plant to retreat these tailings. Within a few months the operation had stabilised and Polymetals was meeting budgeted targets of throughput, metal recovery and concentrate quality. Polymetals and Intec then investigated methods that would improve the metallurgical result for this difficult to treat tailings. Since the tailings are fine-grained with 80 per cent <45 ¦m, magnetic aggregation of the paramagnetic sphalerite was evaluated. Magnetic aggregation of an oxidised tailings feed has not been tested before, nor had the technology been available when Hellyer ore was originally processed. Extensive statistical test work showed magnetic aggregation of the sphalerite fines in the zinc cleaner circuit increased total zinc recovery. The increase in the mean zinc recovery with magnetic conditioning was 3.63 per cent, at a statistical level of confidence of 97.8 per cent, and at the same mean zinc concentrate grade.

Jan 1, 2009

By R. H. Lynn, T. C. Craig

During the year 1933, in the Texas Panhandle, 113 oil wells were completed, adding 33,337 bbl. to the daily potential of the field. The field potential on Jan. 1, 1933, as determined by the Texas Railroad Commission, was 149,260 bbl., with a daily allowable production of 41,000 bbl. The potential was raised gradually, until on July 16, 1933, it reached 155,344 bbl. with a daily allowable of 55,000 bbl. This potential and allowable was maintained over a period from July 16, 1933, to Sept. 8, 1933, when the potential was reduced to 136,893, with a daily allowable of 43,727 bbl. Since Sept. 8, 1933, there has been a gradual increase, until on Jan. 1, 1934, the field potential reached 159,740 bbl. with a daily allowable of 42,000 bbl. Of this amount 26,429 bbl. arc "marginal oil" and 2682 bbl. are exempt on account of water. Deepening of Wells During the year 64 wells were deepened, increasing their total oil production 9631 bbl. per day. Of this amount the Gray County granite wash contributed 9256 bbl. from 57 wells. It has been found in many places that the granite wash carries an additional oil pay from 50 to 75 ft. below sea level. The majority of the wells that were .drilled during the early development in Gray County encountered their oil above sea level. When the wells producing from the upper horizon have become unprofit-

Jan 1, 1934

By A. C. Fieldner, W. A. Selvig

Information concerning the fusibility of coal ash has become of considerable value to the consumer of coal, mainly in connection with the troublesome formation of clinker resulting from the melting of the ash constituents of the burning coal. The growing interest in such data has led the Bureau of Mines to make a general survey of the "fusing" or "softening" temperatures of the ash from coals of the United States. It is hoped that this information when used together with the large number of coal analyses published 1 by the bureau will assist the consumer of coal in comparing different coals, and in selecting the coal best adapted for his purpose.

Jan 1, 1922

By BUREAU OF MINES

This report is submitted in accordance with the provisions of the Synthetic Liquid Fuels Act of April 5, 1944 (30 U.S C. 321-325, as amended), which require that: "The Secretary of the Interior shall render to Congress on or before the first day of January of each year a report on all operations under this Act." Owing to the broad scope of the content and the diversity of interests represented, the Annual Report for 1953 has been divided into two separate publications. Each has been published by the Bureau of Mines as a Report of Investigations, and the respective titles follow: R. I. 5043, Part I - 011 From Coal. R. I. 5044, Part II 011 From 011 Shale. - Identical in each report, the introduction summarizes research progress made in 1953 under the entire Synthetic Liquid Fuels program. A free copy of each of these publications may be obtained by a written request to the Bureau of Mines, Publications Distribution Section, 4800 Forbes Street, Pittsburgh 13, Pa. The R. I. number and title of the publication desired should be indicated.

Apr 1, 1954

By Jon K. Ahlness

The Bureau of Mines investigated technologies for testing the integrity of in situ leach mining wells, as required by environmental regulations. To test for leaks, inflatable packers were used to seal the well casing. Laboratory testing determined that the packers could contain a casing pressure up to 50 to 60 psi (345 to 414 kPa) less than the packer inflation pressure. Single-and double-packer configurations were successfully field-tested in 32 wells ranging from 500 to 530 ft (153 to 162 m) in depth. A rigid pipeline and a hoist truck were used to run the packers in and out of the wells for the double-packer tests, which averaged 2-1/4 h each. In an effort to decrease the time of the rigid-pipe double-packer test. a self-contained trailer-mounted test system was designed and built. It utilizes a winch and steel cable to run the packers in and out of the well and high-pressure nylon tubing for packer inflation. This system was successfully field-tested in eight wells averaging 650 ft (198 m) in depth and resulted in a time savings of 13 pct and an operator-hour reduction of 42 pct.

Jan 1, 1985

By Elio Ferreira

This report describes the design, and development work performed to reduce the volume and weight of the miners caplamp battery, as well as a headpiece with a swivel mechanism containing a halogen bulb with two filaments. Work was also conducted in the development of a maintenance free battery. The design concept is based on non-sintered Ni-Cd technology, with an energy density of 22 Wh/lb. The cap lamp system developed has been approved by the Mine Safety and Health Administration (MSHA) and can be manufactured for mine use.

Jan 1, 1988

By DEVY DYSON, Brian Hart, JOHN LANGHANS, Stamen Dimov, STEVE YOPPS

A recent Nevada Gold Mines research program focused on pressure oxidation pre-treatment of a Carlin-type double refractory ore from the Turquoise Ridge Mine. The research team found that both arsenian pyrite and carbonaceous matter were highly oxidized within an hour at 300 °C using a bench-top autoclave reactor and that the gold recovery from the residues after cyanide/carbon-in-leach approached the technical limit set by the amount of gold encapsulated by silicate minerals. Although the 60-min pre-treatment at 300 °C yields robust performance when treating a whole ore, copper additives can catalyze the oxidation rate of carbonaceous matter and reduce the residence time needed at elevated temperature. Certain gangue minerals are susceptible to dissolution in acidic solutions at 300 °C, and this may cause poor gold recovery. This recovery challenge is mitigated by keeping free acid in the discharge solution below a key threshold.

Jun 21, 2022

"The Archaean komatiite-associated nickel sulphide deposits at Kambalda, Western Australia, exhibit a number of stratigraphic features that are indicative of a strong volcanic control on ore localization, including (1) a restriction to specific basal cumulate metakomatiite host units, (2) confinement within distinctive synvolcanic embayments in the footwall and (3) variations in the internal structure and composition of overlying and adjacent barren metakomatiite flow's and the distribution of interflow metasediments with proximity to the ore zones.The high magnesium content of the host units (up to 45% MgO volatile-free) in comparison with that of aphyric or spinifex- textured lavas (16-32% MgO) has been considered previously to indicate either magmas/lavas rich in intratelluric olivine or selective accumulation of olivine phenocrysts. The marked linear trend of the oreshoots, basal host units, footwall embayments and the volcanic stratigraphic relationships have been used as evidence for local linear feeding fissures. Rare relict igneous olivine in some host units is, however, demonstrably not intratelluric, and there is no direct or indirect evidence of a proximal eruptive site (e.g. footwall feeders, pyroclastic breccias, ultramafic intrusives) at Kambalda such as at some other deposits of this type. Kambalda is interpreted as a distal rather than proximal volcanic environment.Emplacement of the komatiite sequence at Kambalda was probably controlled by the locations of a few specific eruptive sites relative to regional topographic gradients and influenced by the topography of the pre-existing volcanic surface. Olivine enrichment in the basal host units occurred by in-situ fractionation and cumulus crystallization of olivine during longitudinal lava flow within linear lava conduits, possibly centralized on depressions between non-overlapping footwall basalt flows. The distinctive stratigraphic relationships are attributed to localization of lava conduits along the volcanic pitchline, flanked by more slowly moving parts of the flows. There are analogies with the physical volcanology of Modern basaltic and Proterozoic komatiitic lava flows.A corollary of this model is that the lava conduits thermally eroded and assimilated sulphidic sediments, contributing additional sulphur to sulphur-saturated komatiites or possibly inducing sulphide separation in originally sulphur-undersaturated komatiites. The latter would account for the restriction of ores to linear cumulate komatiite host units (thermally active lava conduits) and the locally mutually exclusive, but stratigraphically equivalent, relationship between the ores and sulphidic metasediments at Kambalda."

Jan 1, 1984

By David R. Ziegler

The concept and facts concerning "threshold blast damage" are not considered "general knowledge". Perhaps because of a lack of knowledge, understanding, and experience of blasting effects, property owners and lay-persons may attribute a wide range of common cosmetic conditions to "blasting damage".

Jan 1, 1997

By D. Yuan, M. Sitter, S. St. Jean, M. Collins

The Ambatovy Joint Venture comprises an operating lateritic nickel mine, ore slurry pipeline, pressure acid leach plant and nickel refinery in Madagascar. The hydrometallurgical process selected by Sherritt for treatment of the Ambatovy ore is a long-term, sustainable approach to producing nickel. Sulphur, used to prepare hydrogen sulphide, which is used to produce mixed sulphide intermediate, is recovered in the refinery as ammonium sulphate fertilizer. Additional sulphur is used to generate sulphuric acid for treatment of the ore in the high pressure acid leach (HPAL) step; fossil fuel consumption is minimized by using the heat generated from the exothermic reaction between sulphur and oxygen in the acid plant to produce power and steam. Steam consumption is minimized by design of efficient flashing and preheat systems for HPAL, while the high temperature of the HPAL step serves to minimize acid consumption. Fossil fuel consumption by the operation as a whole is further minimized by locating the leach plant and refinery near the port of Toamasina and utilizing a 220 km slurry pipeline to transport ore from the mine to the leach plant. In addition, Ambatovy has demonstrated a strong commitment to sustainability programs such as the biodiversity management program at the mine and local procurement in Madagascar. In this paper, the hydrometallurgical process for nickel and cobalt recovery from Ambatovy ore is described, along with highlights of Ambatovy’s approach to sustainability in Madagascar.

Jan 1, 2015

By Luciano França Rocha

A medição online de umidade de finos de minério de ferro sempre foi uma informação muito desejada nas plantas de pelotização de minério de ferro. Controlar a umidade do pellet feed produzido pela unidade de filtragem além de possibilitar maximizar a produção deste setor da planta garante uma maior estabilidade no processo de pelotamento e de endurecimento. Para conseguir entregar esta medição à sala de controle, iniciamos um projeto utilizando a metodologia Design For Six Sigma para desenvolver uma forma de medição desta grandeza. Inicialmente foi feita uma revisão bibliográfica sobre o assunto. Posteriormente, foram realizadas visitas técnicas que eliminaram algumas possíveis tecnologias de medição. Finalmente, foram avaliadas as tecnologias de Absorção de RF e medição por um braço robótico para serem avaliadas. O primeiro teste industrial foi realizado com um medidor de absorção de RF que não apresentou bons resultados. A faixa de interesse de medição é muito estreita (9% a 11% de umidade). Esse fato exige uma boa precisão do equipamento para que a medida tomada do processo seja útil e sua incerteza não ocupe toda a faixa. Como nenhuma das tecnologias de medição online existentes no mercado se mostrou precisa suficiente para a aplicação, a alternativa foi utilizar um braço robótico para coletar, secar e medir a umidade através do método tradicional feito por um robô. Esta última alternativa se mostrou robusta e adequada ao controle de processo da unidade de filtragem, produzindo resultados confiáveis e precisos.

Jul 30, 2018

By YUSONG MIAO, DI WU, XIANRONG YAN, YIPING ZHANG, JIE LIN, KEBIN LI

Rock fragmentation size distribution is often used as an important index to account for the blasting effect because it directly affects the subsequent loading, transportation, and secondary crushing. Due to the mismatching of explosive and rock wave impedance, high boulder yield often occurs which affects the blasting effect. In this study, methods of measuring rock acoustic impedance, rock strength point loading, and detonation wave velocity have been used to obtain more accurate input parameters. Then, in the watershed image segmentation technique, the Gates-Gaudin-Schuhmann and Rosin-Rammler distribution functions have been used to analyze and quantitatively describe the rock fragmentation size distribution in the existing muck-pile. Finally, taking the rock properties, explosive performance, blasting parameters, and system characteristic variable into consideration, support vector machine (SVM) regression model has been analyzed on the learning and prediction of samples. The results show that SVM has a good prediction accuracy, high precision, and strong generalization ability. The optimized matching coefficient of rock and explosive wave impedance K ranges from 2.50 to 2.58 times. This study has developed a series of simple, accurate methods for rock properties analysis, detonation wave velocity measurement, and muck-pile model image processing, and a basis for predicting and evaluating rock fragmentation size distribution and optimizing the matching coefficient before carrying out a blasting operation.

Jan 22, 2021

By Howard P. Hamlin, John W. Sweeney

Shales , clays , and loess in Iowa were tested and evaluated to determine feasibility of producing lightweight aggregate by commercial rotary - kiln or sintering methods . Preliminary testing was conducted in a muffle furnace . Rotary - kiln tests were conducted in a 16 - inch by 14 - foot rotary kiln . Concrete cylinders and cubes were tested to determine qualities of the aggregate . Three samples made suitable lightweight aggregate by rotary - kiln methods and two by sintering .

Jan 1, 1964

By D K. Weatherley, G R. Ballantyne, S Ali, M Yahyaei, M S. Powell

This paper explores development of a novel ore characterisation method for the precise measurement of practical minimum comminution energy. A monolayer of particles with a narrow size distribution is broken using a precision rolls crusher (PRC); an ore characterisation device developed to overcome the shortcomings of conventional tests. For energy measurement, PRC uses two shaftmounted rotary torque transducers. These transducers acquire precise torque and angular speed data in response to the load applied to the rotating shafts during breakage events, which is converted into energy. The test progressively crushes feed particles down to final product size in many controlled breakage stages. The generation of fines in each breakage stage is then plotted as a function of input energy. The inverse of the gradient of this plot provides the size specific energy (SSE) in kWh/t of material generated below a predefined marker size; -75 μm in this case. The PRC has potential to evolve as a geometallurgical ore characterisation test—it is simple, fast, requires small sample mass (200–300 g), covers a wide feed particle size range (10 mm to 115 µm), and provides ideal SSE measurements that can be used for the calibration of on-site production equipment.

Aug 24, 2022

By G. H. Keith

The Bureau of Mines determined the mechanism(s) involved in observed anomalous changes in mechanical properties of vanadium-base alloys. Tensile properties of electrorefined and commercial-purity vanadium-base alloys containing up to 5 atomic percent molybdenum or titanium were measured between 77° and 673° K. Snoek oxygen and nitrogen peak heights were measured to determine the changes in dissolved interstitial content caused by increasing quantities of solute. In addition, changes in lattice parameter were followed wit: precision X-ray techniques. Softening, observed in alloys containing titanium, is explained by the formation of a second-phase titanium compound with oxygen or nitrogen. However, because of partitioning of titanium between compound formation and solid solution formation, about five times the stoichiometric amount was required for complete reaction. Addition of 1 percent titanium drastically lowered the strengthening due to strain aging, at 673° K, and 2 percent titanium essentially eliminated it. All alloys were ductile at 77° K. Variations in the tensile properties of the molybdenum-containing alloys are explained by variations in the amounts of interstitial impurities present. The molybdenum did not react with these impurities and had no effect on strengthening due to strain aging. Commercial-purity vanadium alloys containing more than 2 percent molybdenum were brittle at 77° K.

Jan 1, 1969

By B. W. Gandrud

The upper part of the Alabama deposits of crystalline graphite consists of an oxidized ore derived from the underlying unoxidized ore through prolonged Weathering. The degree of oxidation in different sections and at different depths within the bed is not uniform. The original ore is hard and blue-gray; the weathered product is soft and brown and is the only part that has been mined to any extent. Samples of both oxidized and unoxidized ores were obtained from two of the large graphite deposits of Clay County. Three additional samples of oxidized ore were obtained from different portions of a third property in the same region. In this report, ores 1 to 5 are of oxidized material and ores 6 and 7 of unoxidized.

Jan 1, 1934

By Nilufer Kursunoglu

Despite being crucial for meeting the world’s energy demands, coal mining operations present considerable health risks, especially when it comes to exposure to coal dust. Longwall coal mining, an advanced technique, has considerably enhanced production but made dust control more difficult. Due to its explosive nature, coal dust continues to be a serious and dangerous concern in the industry despite developments in safety technology. This study aims to comprehensively assess the risk of coal dust explosions by integrating fuzzy risk matrix and Pareto analysis methodologies, offering precise risk ratings for various root causes. A fuzzy risk matrix was developed to assign exact risk ratings to identified root causes. Additionally, a Pareto chart was used to identify the main reasons and suggest particular preventive measures. 17 significant causes were determined for underground coal mines based on the study’s methodology, and some preventive measures were suggested. In accordance with fuzzy risk rating values, root causes were divided into six categories. The root hazard with the highest risk rating was identified as ‘accumulation of inflammable gas/gases’. The proposed approach was used to examine incidents caused by coal dust explosions in Turkish coal mines in order to demonstrate the effectiveness of combining the fuzzy risk matrix and Pareto analysis for assessing coal dust explosions. This study gives not only a solid framework for risk assessment but also critical information for classifying the risks associated with coal mine dust explosions. The results highlight the critical necessity for proactive and preventive actions to reduce the hazards of coal dust explosions and protect the safety of mining workers.

Nov 16, 2023

By M. Z. Emad, M. U. Khan, A. ur Rehman

The use of stemming plugs in surface blasting is gaining popularity because of the environmental, technical, and economic advantages. Although previous studies have established the operational effectiveness of different types of stemming plugs, evaluations of the economic and ergonomic impacts are lacking, thereby hindering their application in many mining operations. Consequently, a significant proportion of mining operations end up performing less efficient blasts. We evaluated the effectiveness of three types of stemming plugs by conducting multiple full-scale production blasts. The results show that stemming plugs reduce the need for secondary blasting and increase blast performance. An economicanalysis showed that the incorporation of stemming plugs can reduce blasting costs significantly.

Jul 1, 2021

By J. K. Whyatt

Researchers at the U.S. Bureau of Mines collected and analyzed overcore measurements and other indicators of in situ stress characteristics at the Lucky Friday Mine, Mullan, ID. An analysis of these data revealed that significant local variations in in situ stress are present in this mine and that these variations existed prior to mining. High stresses were found to be associated with the most competent strata and a locked section of a fault. An estimate of the predominant stress field was developed for mine-wide modeling. The estimate shows that the greatest principal stress was oriented north of northwest. This information should provide a basis for mine-wide structural modeling of the Lucky Friday Mine and should generate important insights into localized stress conditions, which may significantly affect both local and mine-to-mine variations in seismicity induced by excavation.

Jan 1, 2010