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By Gilbert C. Robinson

Manufacturers of brick and tile are showing growing interest in the possibility of manufacture of a clay bonded block. The block would have the shape of concrete block, but would be made without the use of Portland cement, Instead, the block would be made' from mixtures' of an aggregate and the present raw materials of the brick industry. The finished units would weigh 20 to 30 pounds and meet the specifications for Grade A concrete block. The present status of the clay block development shows one manufacturer actually in production of these units$, two additional manufacturers are attempting production and many manufacturers are actively engaged in development work. At least four major research laboratories are engaged in the development program. There are several different processes available for clay block production. These processes differ primarily in the type of aggregate used or in the type of forming operation selected. I would like summarize these possible methods.

Jan 1, 1960

By F. C. Appleyard

A couple of miles southwest of the town of Saltville in the western tip of Virginia is a little village called Plasterco. Gypsum has been produced in this area since about the year 1815, being originally found as small outcrops at the surface. Production in the early days was very small, and the use of the mineral was limited to that of "land plaster" or ground gypsum which was spread on the land to sweeten the soil. In the late 1800's, a small calcining plant was constructed and the production of gypsum plaster began. About this same time, the surface rock was depleted and it became necessary to begin underground mining operations in order to maintain a continuous supply of raw material. The United States Gypsum Company became interested in this property in 1909, and has operated there ever since, having enlarged the calcining mill and built a plant for the manufacture of gypsum wall-board in the middle 1920's. Production of gypsum continues from underground' mining operations, and the present mine at Plasterco is now about 1,000 feet below the surface, making it the deepest gypsum mine' in the world.

Jan 1, 1965

By Ralph B. Hall

Examination of cored material from the Southern Extension of the Florida Phosphate District has indicated a decidedly complex and diverse sequence of phosphatic sedimentary units. The perfunctory logging techniques formerly used in the Central District are inadequate to properly describe the intricate geology of these sediments. Adequate geologic training and familiarity with the potential ramifications of his judgement are a necessity for the logging geologist. A combination descriptive-graphic logging model is proposed that utilizes a standardized sediment nomenclature system and descriptive symbols for type materials commonly found in these sediments. Justification for adoption of this or a similar logging model is discussed.

Jan 1, 1983

By William E. Mead

Although this paper has been entitled "Design of Embankments for Tailings Ponds and Waste Dumps," a better title might have been "Site Selection and Design Planning for Tailings Ponds and Waste Dumps," The procedures normally followed in performing the engineering calculations based upon the measured soil properties will not be detailed. Instead, we shall look at the subject in broader perspective which considers the environmental factors and the fundamental design principles. Disposal of waste materials left from the extraction and processing of mineral deposits has become, in recent years, an important engineering consideration for mine and mill operators. Land occupancy and land values almost everywhere are increasing at a rapid rate. So is the size of mine and mill waste dumps, thanks to our advancing technology in mineral beneficiation. Mining companies are being pressured to "clean up" their operations, both literally and in a safety hazard sense. Once, long ago, the miner could use any convenient location to get rid of his mine waste and mill tailings without being concerned over possible infringement on the rights and well-being of the public. Today, however, he must pay close attention to these matters if he wishes to avoid liability suits and the unfavorable reaction of civic groups as well as local and regional government. Most operators keenly sense their increased responsibility, not only because they are legally vulnerable, but because they realize the necessity for sharing space harmoniously with the rest of society.

Jan 1, 1967

By J. R. Koehler

Mining practices at the Sunnyside Mines, Sunnyside Coal Company, Sunnyside, UT, have been documented by U.S. Bureau of Mines researchers to preserve the extensive history of yield pillar-based longwall gateroad system evolution on the property. An overview of the historical mining conditions, practices, and innovations that resulted in the evolution of the two-entry yield pillar gateroad system currently employed at Sunnyside was developed from interviews of 30 long-time Sunnyside employees. Employing yielding chain pillars at Sunnyside virtually eliminates tailgate pillar bumps and contributes to reducing face bumps. Limiting the overall width of the gateroad system benefits bump control and especially, roof and floor stability.

Jan 1, 1994

By N. O. Lotter

The reliability of a set of flotation results is key to minimizing project risk, either at the commissioning of a concentrator or at the point of implementing an improvement to an existing concentrator operation. High-confidence flotation testing (HCFT) was developed for this purpose and is part of the list of technologies at various scales used by Xstrata Process Support (XPS) in addressing these projects. The methodology is based on two principles: one, to ensure that the ore sample is representative and has been well-blended and subsampled; two, to perform the flotation tests in sufficient numbers of replicates with appropriate quality controls, so as to improve the reproducibility of the test data. Across ten years of research on this methodology at Xstrata Process Support, Sudbury, several improvements to the HCFT method and complementary connections between sampling and quantitative mineralogy have been developed. Two case studies are reviewed. These show the capability of this system in both optimizing an existing concentrator operation and in serving a new mine scenario. Further work to improve the efficiency of this procedure has been identified. Key words: Flotation testing, Flotation

Jan 1, 2010

By J. R. Kadambi, C. Shingote, J. Furlan, R. Ke

"Hydrocyclone separators are widely used in various industrial applications in the oil and mining industries to sort, classify and separate solid particles or liquid droplets within liquid suspensions, which are considered to be multi-phase systems. Numerous valuable studies have been conducted in recent years to investigate the flow fields inside hydrocyclones. However, much of the information regarding the performance of cyclones in the literature has limitations, based in some part on the respective current-available theoretical models, and much of it cannot be considered as completely applicable to most real-world applications; many of the studies investigated the flow fields within extremely simplified hydraulic designs that are not representative of the complex geometries or large sizes which are typical in industry. Therefore, in this study, the two phase flow system inside the actual hydraulic geometry of a milling circuit hydrocyclone was explored with the aid of both computational and experimental techniques (Particle Image Velocimetry). In this study, the flow field with an air core has been investigated; in essence, the research was a two-phase problem, which caused some challenges on both the computational and experimental sides. Two turbulence models were used in the numerical calculations: the Reynolds Stress Model and Large Eddy Simulation. The computational studies are mainly focused on the prediction of the dimensions and shape of the air core. Different section planes of the hydrocyclone were selected as planes of interest and then were divided into several fields of view (FOV) for PIV measurements. Two dimensional experimental velocity vector maps were obtained in each of the fields of view. The computational results were validated globally using pressure and flow rate readings at the boundaries and locally by comparison to the PIV velocity vector maps and profiles. Keywords: Computational fluid dynamics (CFD); Hydrocyclone; Particle image velocimetry (PIV); Reynolds Stress Model (RSM); Large Eddy Simulation (LES). INTRODUCTION A hydrocyclone is a device used to separate a solid-liquid, liquid-liquid, solid-gas, or liquid-gas suspensions into at least two separate density or particle size components. Hence, the flow field of the hydrocyclone is generally considered a multi-phases flow system. Application of hydrocyclones have been used in numerous industries including oil, drilling, metal working, and mineral processing since 1891, when E. Bretney obtained the first patent for the predecessor design of all contemporary hydrocyclones. A modern hydrocyclone typically consists a cylindrical section at the top where the liquid is being fed tangentially, and a conical chamber attached to the bottom of the cylindrical section, as shown in Figure 1. The characteristics of the feed stream that is injected into the cylindrical chamber play a significant role in hydrocyclone operation. The inlet is tangential relative to the cylindrical chamber and hence causes a centripetal force in the flow field which is considered as the primary separation mechanism."

Jan 1, 2017

By T. W. Flemal

Good afternoon gentlemen. To begin, may I say ?thank you? to the AIME for the invitation to be here today to talk about my company's experience with shovel, truck, pocket, to car loading. The other author of this paper is here today. (Introduce John Sweet). Before we get to the details of this paper I want to tell you a little about Erie Mining Company. Erie Mining Company is located on the east end of the Mesabi Range in northern Minnesota and is engaged in the business of processing taconite rock into iron ore pellets. In 1970, the twelfth year of production, Erie will produce its rated capacity of 10.3 million tons of high grade iron ore pellets. The plant is the first of five iron ore pelletizing operations managed by Pickands Mather & Co. with a combined annual production capacity of 21 million tons. This plant began producing high grade iron ore pellets in 1957 placing it among the earliest of taconite production facilities in North America. Historically Pickands Mather & Co. had been a leading natural ore mine managing firm in the Great Lakes region for more than 70 years. Pickands Mather & Co. moved into the new field of taconite mining and processing with management and operational experience from the open pits and underground mines. We were to learn much of volume taconite handling requiring new equipment and new procedures. A trial and error period through the early years of taconite processing developed through the operation of an experimental sized preliminary plant near the present Erie Mining Company site.

Jan 1, 1970

By M. L. Wouden

The Bureau of Mines investigated pegmatite and granite formations at Copper Mountain, Fremont County, Wyoming, for recovery of tantalum and niobium. Sampling of surface exposures identified about 1.27 mega tonne of pegmatite resource material ranging between 0.02 and 0.04% Ta20, and 0.007% Hb20,. Beneficiation studies were conducted involving coarse-grained and fine grained pegmatite samples. Over 80% recovery of the coarse-grained tantalite was achieved in a concentrate averaging over 45% combined tantalum-niobium oxide. Lower concentrate grades and recoveries resulted from the treatment of fine-grained pegmatite.

Jan 1, 1991

By Y. C. Kim

An alternate development drilling strategy to the one currently in use at the nine was investigated using geostatistics for a portion of the pit. The study area consisted of 4,000' x 5,000' in plan and 1,080' in elevation. The massive orebody, the three-dimensional nature of the problem, and the location of ultimate pit limit in the study area all created some unique problems in devising the development drilling strategy, as compared to the two-dimensional tabular deposits such as coal deposits. Rather than using the confidence interval of the global reserve estimate as the main criterion for development drilling, the confidence interval of short and medium range mine planning blocks was used as the objective. Based on somewhat arbitrarily selected level of confidence, the results from this study showed that a total of 50 DDHs rather than the planned 62 DDHs is sufficient in the study area, if the selected confidence levels are acceptable to the management. This paper also emphasizes the importance of the particular objectives being used in development drilling and how they influence the "optimai" place- ment of the development drill holes.

Jan 1, 1981

The impact of smoothing on the definition of ore and waste boundaries using linear estimation and conditional simulation methods is discussed. The nature of transfer functions is examined including their ability to incorporate categorical data (e.g. a dominant lithology code). An Ore Block Optimization (OBO) transfer function is presented that provides a clear guide for the mining geologist. Advantages are seen in defining stockpile cut-off grades and meeting production targets such as maximizing head grade, maximizing ore tonnes or minimizing ore loss or dilution. Each of these scenarios impacts on mine profitability and grade control.

Jan 1, 1999

By E. R. Bauer

In response to the mandates in the MINER Act of 2006, the National Institute for Occupational Safety and Health (NIOSH) conducted refuge alternatives research that included characterizing the utility, practicality and survivability of refuge chambers and outby safe havens. NIOSH also prepared and delivered a report to Congress in late December 2007 that summarized the findings of the re-search, included recommendations concerning the design and performance specifications for refuge alternatives, and focused on specific information that could inform the regulatory process on refuge alternatives. This paper highlights NIOSH?s research and recommendations concerning refuge alternatives, survivability evaluations of refuge chambers and presents a brief review of the current deployment of refuge chambers in underground coal mines in the U.S. The research has lead to the conclusion that refuge alternatives have the potential for saving the lives of mine workers if they are part of a comprehensive escape and rescue plan and if appropriate training is provided.

Jan 1, 2009

By G. A. Campbell

This paper considers the international market trends of the rare earths and how they are strongly influenced by the by-product/co-product nature of their mining and processing. The two main economic minerals for the rare earths are bastnasite and monazite. Monazite is primarily a by-product of mining ilmenite and rutile and is affected by changes in these markets as well as the presence of thorium. Bastnasite is a by-product of mining iron ore in China and a stand-alone product in the USA. The paper will use conceptional relationships and empirical data to delineate the various by-products/co-products relationships and how they determine observed international market behavior.

Jan 1, 1996

By Mason L. Dicks

For many years The Hanna Mining Company has been investigating the flotation of the non-magnetic iron ores located in the Western Mesabi Range of Minnesota.1 During the 1950's a number of anionic iron procedures were evaluated and in the late 1950's and early 1960's the anionic silica floats and the cationic silica floats were tested with improved results.2 The cationic float became more attractive and effective by the use of the improved ether amines. About 1962 a desliming process by selective flocculation was developed by the U.S. Bureau of Hines at Minneapolis', Minnesota.3, 4, 5 This is a very efficient method of desliming and was first tried with the anionic silica float and then the more practical cationic silica float. In the mid 1960's The Hanna Research Laboratory began studies to optimize the selective flocculation process for our ores. This was followed by studies to optimize the cationic silica float after desliming by selective flocculation. This testwork was done on large, 500 to 1000 tonne bulk samples of oxidized taconite which were later successfully piloted at .68t/h (1500 Lbs. /hr.). A program was then begun to test the oxidized portions of numerous taconite drill holes to outline the ore bodies and develop mining plans. This paper will discuss our optimization results of both the selective flocculation and the cationic silica float as applied to our various ores. In addition the pilot plant studies and drill core testwork will be discussed.

Jan 1, 1978

By P. Munjal

"Usage of Supercritical CO2 in place of high pressure freshwater has proven to be a potential breakthrough in the technique of fracturing. Tapping of carbon footprints from feasible sources like industries can be used to manufacture Supercritical CO2 required for fracking. Supercritical CO2, being less viscous than water, creates complex and coherent micro-fractures which can connect many more natural fractures greatly, increasing maximally the fractures’ conductivity leading to an increment in production. The better clean-up property of Supercritical CO2 provides auxiliary benefits of immediate evaluation of fracture zones, usage of an optimized quantity of mesh proppant and elimination of the need of swabbing. Also, Coal has a stronger affinity for CO2 than for CH4. When CO2 is present, CH4 on coal is replaced by CO2. This also ensures rigorous recovery of gas from the coal beds. Use of Supercritical CO2 will obliterate many problems as the CO2 used for fracturing is either sequestered beneath the crust or is recovered at the surface and reused. Therefore, injecting CO2 into coalbeds achieves not only enhanced CBM recovery, but also greenhouse sequestration underground. INTRODUCTION Coalbed Methane At various times in the geologic past, earth had dense forests in low-lying wetland areas. Due to natural processes such as flooding, these forests were buried underneath the soil. As more and more soil deposited over them, these dead plant remains were compressed. As the process continued the plant matter was protected from biodegradation and oxidation, usually by mud or acidic water. Under high pressure and high temperature, dead vegetation was slowly converted to coal. The omnibus process of formation of coal, thus, comprises of conversion of dead plant matter into peat, followed by its conversion to lignite, then sub-bituminous coal, after that bituminous coal, and lastly anthracite. This process of enrichment of coal as it is progressively forced deeper into an ambience with higher temperature and pressure involves biological and geological processes that take place over a long period and is called coalification. During coalification, large amounts of methane-rich gas are generated and stored within the coal on internal surfaces; hence comes coalbed methane. Coalbed methane (CBM), a gas formed as part of the geological processes that are responsible for the generation of coal, is adsorbed into the solid matrix of the coal during its formation process. Coalbed methane is distinct from a typical sandstone or other conventional gas reservoirs, as the methane is adsorbed and not absorbed. The methane is in a near-liquid state, lining the inside of pores within the coal. The open fractures in the coal that result from the liberation of volatile materials (and subsequent contraction due to the liberation) from the coal due to the high temperature and pressure conditions encountered, called cleats, may also contain free gas or can be saturated with water."

Jan 1, 2015

By A. S. Azman

In collaboration with Kennametal Inc. and corry rubber corporation, the U.S. National Institute for Occupational Safety and Health (NIOSH) developed a drill bit isolator to address noise overexposures associated with roof bolting machines in underground coal mines. NIOSH laboratory studies confirmed that the drill bit isolator reduces noise during drilling. Field studies were needed to confirm that a noise reduction could be obtained under working conditions and that the device was sufficiently durable. This paper reports results of field tests of the device conducted at five underground coal mines. Noise reduction was assessed by comparing the operator?s noise exposure during drilling with and without the drill bit isolator. Durability was assessed by recording the number of holes and total feet drilled with each bit isolator until either the test period ended or the device failed. The results from these tests showed that the device is an effective noise control in a mine environment. The field-tested drill bit isolators provided a noise reduction of 3-5 db(A). Of nine devices tested for durability, five exceeded 610 m (2,000 ft) drilled and two exceeded 762 m (2,500 ft) drilled before failure. Durability issues found in the field tests led to final production optimizations that have resulted in a commercially available product for drilling with 35-mm- (1.3-in.-) diameter roof bits and hexagonal drill steels.

Jan 1, 2012

By Richard H. Johnson

White Pine Copper Company began operating a plant designed to recover copper matte particles from its discarded reverberatory furnace slags in April, 1972. Seasonal operation, generally the months of April through November, continued through October, 1974, shutting down due to feed exhaustion. White Pine reverberatory furnace slags contained economically recoverable amounts of copper for a variety of reasons. Among them: 1. White Pine concentrates yield extremely high matte grades (65+% Cu) and viscous slags. The viscous slags hinder matte settling causing matte "prill" entrapment in the slag 2. White Pine's total refined copper output is accomplished through fire refining requiring special techniques for impurity removal, especially small amounts of nickel introduced from purchased pyrite and chalcopyrite fluxes. These special techniques result in high-copper slags, refractory to smelting, being reintroduced into the reverberatory furnace. 3. Furnace bottom build-ups resulting in mechanical matte entrapment through the formation of "dams" hindering matte flow. 4. Occasional concentrate fluxing and furnace atmosphere control problems.

Jan 1, 1975

By Bronson Stringham

The close area! relationship of Cretaceous or later intrusive porphyries to larger hydrothermal deposits of Pb, Zn, Au, fig, Cu, Mo, Hg,, and U of similar age in the Basin Range Province, was statistically shown in a recent paper (Stringham1) During the past year this study has been expanded to cover p11 of the larger hydrothermal deposits of similar nature occurring in the entire western United States. The sandstone type uranium deposits of the Colorado Plateau and Wyoming have been excluded since considerable controversy exists regarding their origin. The close relationship between intrusives in general and hydrothermal ore deposits has long been-recognized, but the association involving intrusive porphyry only, was suggested in 1954 when Sales concluded that the formation of porphyry may be an intermediate stage of activity between the development of granitoid rock and certain types of copper deposits. However: he applied this concept to only a few copper deposits. The relationship appears to be true also for a great majority of the hydrothermal deposits of the other metals mentioned above of Cretaceous and later age, at least in the western United States. This situation then leads to the conclusion then when exploring for similar types of hydrothermal deposits of the metals considered one may feel reasonably sure that if an intrusive porphyry of considerable size is. not present he may be facing much greater risk of finding an ore body than if a prophyry were presents Since, there are many intrusive porphyritic rocks which do not seem to be associated with hydrothermal deposit, it is believed that some distinct value can come from the recognition of intrusive porphyry which might be barren as well as the intrusive prophyry which might be productive This paper deals with that problem.

Jan 1, 1960

By William G. Schultz

Sylvite of Canada, a wholly owned subsidiary of Hudson Bay Mining and Smelting Co., operates an 8000 TPD potash mine and refinery located nine miles North East of Rocanville, Saskatchewan. Prior to Hudson Bay's entry in 1968 into potash mining and refining, it was one of the more traditional and conservative Canadian Mining Companies whose principal business had been for many years a successful copper-zinc mining and smelting operation located at Flin Flon, Manitoba. The potash reserves being mined by Sylvite were acquired through the acquisition of Francana Oil and Gas. This acquisition was at the time when several major potash mines were being developed or had recently been brought into production in the Province. These mines are owned by either very substantial Canadian Mining Companies or Multi-National Mining Companies with considerable potash mining experience. At that time, it became very apparent because of the new mines coming into production, potash mining and refining would quickly become a very competitive industry. Because of long term considerations, Hudson Bay decided to proceed with the development of its potash reserves, recognizing the Mine and Refinery would have to be the most advanced available in order to successfully operate. This report deals with the mining operation at Sylvite and the degree of success Sylvite has achieved.

Jan 1, 1972

By M. D. Banghart

The Republic of South Africa is an outstanding example of the benefits to a new land by the application of individual enterprise, capital and know-how. While South Africa was colonized by European and Bantu people some 300 years ago, it was only 70 to 80 years agog when diamonds were discovered at Kimberley and gold on the Witswatersrand, that the mining, industrial and commercial potential of the country began to emerge. South Africa s national income rose from R1, 200 million in 1945 to over R4 billion in 1960 (1R = 10 shillings = $1.40 U. S.) The annual national income per head of population -- including all races -- is currently R254 (£127) This compares with £24 for India., £30 for Nigeria, and £50 for Ghana. Allowing for the increase in population, the increase in real income per head of population was about 40% during the past 15 years.

Jan 1, 1962