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By Timothy J. Myers

Expansion and the economic growth in the southwestern region of Missouri necessitated the expansion of State Route 249 and the construction of a new interchange to provide service to the Joplin, Missouri area. The project is located above a former lead and zinc mine in Jasper County, Missouri and includes a five bridge interchange connecting State Route 249 and US Route 171. The variable subsurface conditions, both natural and manmade, prompted the design team to use ground improvement via grouting and small diameter micropiles to provide support for several of the bridge foundations on the project. The scope of work included mine shaft closures, 56,000 ft of overburden and rock drilling, 11,139 ft of micropiles, 524 cy of balanced/stabilized high mobility grouts, and over 8,700 cy of low mobility grout. The selection of the grout used was based on the actual subsurface conditions. Low mobility grout (LMG) was used in voided conditions and for closure of the mine shafts encountered during the excavation. High mobility grout (HMG) was used in fractured rock with the goal of improving the mechanical properties of the rock underneath the future bridge footings and controlling grout volumes during micropile installation. The split spacing method was utilized for both LMG and HMG holes. Geology of the project site subsurface consisted of extremely variable bedrock with strong to very strong limestone, chert, breccia, extremely weak shale, and weak to strong sandstone. Previous activities associated with the mining disturbance (such as partial filled vertical mine shafts, shallow and deep mine horizons, modified hydrology including artesian conditions) further complicates the site subsurface conditions. Real time monitoring and recording of all drilling and grouting parameters was conducted to assist in the evaluation of in-situ geological properties of the site in order to modify the ground improvement and micropile program as necessary. This paper will discuss the design and execution of the ground improvement and micropile program. The project is an excellent example of the use of multiple ground improvement and foundation support techniques combined with real time data analysis to provide a foundation support solution for a complex geological environment.

Jan 1, 2009

By Bruce Mathema, Steven Huynh, Terry Cheng, Gerry Gomez

"The use of PM40N, a specialty precious metals promoter in conjunction with a standard Xanthate based collector was extensively investigated in the flotation of a complex, silver-bearing, lead-zinc ore containing naturally occurring graphitic gangue. The ore, considered difficult to treat with conventional reagents, was tested at plant scale to determine the impact of the promoter on silver recovery, lead grade and also on the amount of zinc misplaced to the final lead concentrate.Initial laboratory-scale rougher flotation testing implied significant improvements in the recovery of silver and lead with a marginal amount of zinc displaced. Subsequent mini pilot flotation tests further revealed that a gain in selectivity and recovery could be achieved by adjusting PM40N promoter dosage and incorporating a cleaner flotation step, further improving rejection of sphalerite. Plant trials resulted in an improvement of 3% in Silver recovery coupled with a 2% increase in recovered lead whilst maintaining lead grade in the lead circuit.To date, the use of PM40N as a promoter has enabled the processing operation to significantly increase its plant economics. The partial replacement of the standard Xanthate based collector has also reduced the overall quantity of Xanthate required in the standard circuit by approximately 10% - which is a positive impact on the environment. It is envisaged that further optimization of plant parameters will favor stable operation and continue to boost revenues generated by subsequent improvements in silver metallurgy."

Jan 1, 2014

Cuspidine (3CaO?2SiO2?CaF2) is one of the most important compounds crystallized in mold flux films during casting in the continuous casting process of steel. The primary crystallization field of cuspidine has been experimentally developed in the CaO-SiOrCaF2-SiF4 system. The cuspidine-NaF binary and cuspidine-CaF2-NaF ternary systems have been also experimentally determined to study effects of addition of NaF on the primary field of cuspidine. In order to discuss its thermodynamic stability the standard Gibbs energy of formation of cuspidine has been determined by an electromotive force method using CaF2 as solid electrolyte and a transpiration method as follows: The chemical potential diagram and constituent activities for the CaO-Si02-CaF2 system have been evaluated based on the obtained thermodynamic data.

Jan 1, 2003

By W Russell

This is an account of Cominco's explosives development work spanning 20 years from the introduction of ANFO into underground operations through to the present day where the use of blasting agents and sophisticated detonation systems create improved safety and blasting efficiency.

Jan 1, 1982

By Andrew Torok

Activated bleaching clays, so called because of their ability to remove color bodies from bleach fats and oils, are produced from clays of bentonitic origin. Activation is achieved by subjecting these clays to physical or chemical alteration to increase selective sorption capacities (1) . The future of activated bleaching clays depends upon the ability of producers to recognize the new areas of applications which are arising, and their skill in developing sophisticated active clays to meet new and stringent requirements. The major portion of activated bentonites are produced for decolorization of oils. New techniques of activation will improve these clays for broader spectrum use. General properties expected to result from present activation methods are: 1. Modification of hydrophobic-hydrophilic properties and increased available surface area in non-aqueous systems, thereby improving sorption capacity and ability to remove color bodies from oils. The following additional properties will be expected from future activated clays: 2. High purity of the active clay with interfering impurities totally removed. 3. Increased selective sorption capacity in aqueous systems. 4. Selective chemical reactivity, such as oxidation or hydrolysis. This property is required for removing

Jan 1, 1971

By L. W. Kelly

The purpose of this paper is to describe several methods that have been employed in successfully recovering roof bolts in Indiana, Illinois, and western Kentucky coal mines, the States where successful roof-bolt recovery was started. As far as is known, the first bolts were recovered in a mine in western Kentucky in January or February 1951. In April 1951 a meeting was held at that mine to discuss the recovery of roof bolts. The meeting was attended by A. D. Sisk, former Chief, Kentucky Department of Mines and Minerals; and L. W. Kelly, Federal Bureau of Mines; and officials of the coal company. Inasmuch as roof bolting was in its infancy, the thinking regarding roof bolts at that time was on the problem of getting them in, not getting them out; consequently, the thought of recovering them was revolutionary. The subject was discussed at length from all angles, and it was finally agreed that, if certain safeguards were taken, no agency represented at the meeting would oppose the practice. That this decision was sound has been proved, as thou-sands of bolts have been recovered in the Middle West without a lost-time accident. Recovering roof bolts is a simple operation; consequently, no complicated equipment had to be designed or built for this purpose. However, about 5 years ago, officials of the Traux-Traer Coal Co. conceived the idea and constructed a mechanical device for recovering bolts that has been very successful and has been copied widely in this area. This device will be discussed in detail in part II of this paper.

Jan 1, 1958

By R. J. Pugh

The coagulation of dispersions of weakly magnetic oxide mineral ultrafines (such as natural hematite or chromite) in an external magnetic field can be described from inter-particle forces. Essentially, coagulation occurs when the short range London-van der Waals interactions and the long range magnetic forces outweigh the stabilizing electrical double layer repulsion. From the classical colloid chemistry theory, we have calculated the various components of the potential energy for different sized particles at a series of ionic strengths and magnetic field intensities. We have related this theoretical analysis to experimental studies where the magnetic field-induced coagulation of ultrafines of natural hematite and chromite in aqueous suspensions was investigated using a laboratory scale electromagnetic solenoid. The experimental results relate the coagulation process (as determined by magneto-sedimentation analysis) to the particle size, the slurry pH and the external magnetic field. In the magnetic fields, maximum coagulation occurred near the pH of zero point of charge (pHzpc) of the minerals (where the electrostatic double layer repulsion was reduced to a minimum) enabling the particles to enter the "primary minimum" energy sink. On the other hand, in cases where the electrostatic repulsion was not suppressed, then the long range magnetic forces enabled coagulation to occur in the "secondary minimum". This caused the formation of chains which appeared to be relatively stable during sedimentation.

Jan 1, 1993

By Chris M. Healey

"Abstract - Perhaps the single most significant variable in the evaluation of a mining project is the reserve estimate. Many parameters are considered when estimating reserves, among them geology. This paper examines the link between the quality of a reserve estimate and a good understanding of the geological controls for the deposit. A clear understanding of the geometry is essential to the accurate definition of the shape and size of the deposit. This includes the definition of any structural controls as well as the proper interpretation of the stratigraphy. Further when the distribution of grades is erratic and there is consequently a high nugget effect, there are significant problems in estimating the true grade of the deposit.Two Saskatchewan examples are presented, one with good knowledge of the controls and therefore good estimates of reserves, and the other with a poor understanding of the geology and resultant problems in deriving good estimates. In both cases the reserve estimates at various stages in the project development are compared to actual results from underground work. The first example is the Star Lake Mine where just about all the estimates were within 10% of the actual on both tonnage and grade. The Laurel Lake deposit is discussed to show how problems in interpreting the geological data make reserve estimation very difficult. Laurel Lake has the additional problem of erratic grade distribution."

Jan 1, 1992

By Carlos Herrera, Paulo Alcazar, Alex Conco, Fremy Flores

Las redes neuronales artificiales son un subconjunto del machine learning y están en el corazón de los algoritmos de Deep learning reflejando el comportamiento del cerebro humano, permitiendo así que las soluciones tecnológicas reconozcan patrones y resuelvan problemas comunes en los campos de la IA. Este modelo matemático es capaz de aprender a través de un aprendizaje supervisado de patrones de conocimiento. Se investigó una solución que involucra cuatro tipos de sistemas.

Sep 30, 2022

By Enrique Monge

Dado que a nivel universitario existen pocos laboratorios adecuados de Física y Química en el Perú, se ha desarrollado proyectos de laboratorios privados y plantas experimentales tanto en el campo analítico y metalúrgico que encauzen la industria minera por el sendero de la técnica más elemental. En ese sentido, el presente texto señala la importancia de los laboratorios de investigación para las industrias mineras y metalúrgicas a través de la Universidad Nacional de Ingeniería y el apoyo del Estado. El laboratorio está dividido en 6 secciones: Minería, preparación y concentración de minerales; metalurgia de minerales no Ferrosos; carbón; fierro y acero; metales y aleaciones.

Jan 1, 1959

By T. L. Joseph

The size and accessibility of the Minnesota manganiferous iron ore deposits make them attractive as a potential source of erromanganese, which is essential in the production of steel. For several years the Bureau of Mines has been conducting experiments to determine the feasibility of producing ferromanganese from these ores by a three-step process which involves (1) the smelting of the ores in the blast furnaoe to produce a high-phosphorus spiegel; (2) the treatment of the spiegel produced from step 1 in an electric or open-hearth furnace to separate the manganese from the phosphorus and the iron; and 3) the smelting of the high-manganese slag from step 2 to produce forromanganese. The details of the first two steps of the process and the results of tests with the experimental furnaces Lave been given in previous reports.5 The m$ or part of the experimental work on the second step has been conducted in a half-ton open-hearth furnace. Some preliminary tests showed, however, that the electric furnace has some distinct advantages over the open hearth for producing, from high-phosphorus spiegel, a slag containing from 45 to 55 per cent manganese and phosphorus and iron in amounts required for ferro-grade ore. The electric furnace tests described in this paper were made to get more information as to the possibilities of the electric furnace in connection with this problem and to study the fluxing effect of alumina on high-manganese slags. Herty, Conley, and Royer have reported' results of laboratory tests which showed that slags containing from 60 to 75 per cent MnO, from 8 to 10 per cent S102, and small amounts of CaO MgO, and FeO, were sufficiently fluid at 1,450° to 1,550° C. to pour readily if 12 to 14 per cent alumina was present. With a normal A1203 content resulting from the A1203 in the

Jan 1, 1931

By Walter G. Perkins

T SEEMS almost sheer presumption to attempt' to discuss Russia in its present chaotic political and economic condition, and were it not that at least two certain absolute factors are continuously at work, it would be impossible to' even approach the subject with any degree of intelligence. These are the inborn love of peace of the people and the national character of the cooperative movement. The love of peace inborn in the soul of every Russian, the desire to be left alone and to- live his life among his home village surroundings, is probably one of the two greatest factors that will make the continuance of the present conditions of civil war impossible. One army or the other may sweep up and down the country. but the Russian peasant will: remain in his own village if not literally darken out. This love of peace is evidenced by the fact that there is no country where personal safety is greater than in Russia in normal times. I have traveled in many isolated parts, carrying considerable sums of money and persolial equipment that; in itself, would be a fortune to any peasant, and have never even encountered a condition in which the most wildly imaginative person looking for adventure, 01: trouble, could muster up even a suspicion of fear. This statement applies also to Southern Siberia and Northern Turkestan, which are inhabitated by the nomadic tribes of Khirghese origin.

Jan 1, 1920

By J. W. Gregg, P. M. Dranchuk, D. L. Flock

"From preliminary investigations it has been observed that although evaporation losses may be estimated by comparing single values of certain physical properties of crude oils and their evaporation residues, such techniques possess little accuracy unless both the evaporation process and the variation of the property as a function of the process are completely known. The accuracy of estimation may be increased somewhat through the comparison of property mid-per-cent curves. Further increases in accuracy are possible if bottoms yield •curves rather than mid-percent curves are used. The use of both the mid-percent and bottoms yield curves however involves a prohibitive amount of effort in most cases. Examinations of distillation bottoms from Hempel type distillations carried to end points just short of the cracking point have indicated that these bottoms are not appreciably affected by the evaporation process. It was further observed that bottoms of identical API gravity, obtained from a crude oil and its evaporation residues behave as if they were pure components which were unaffected by evaporation. Based on these observations Hempel distillation bottoms of equal API gravity were obtained for a crude oil and its various evaporation residues from API gravity bottoms yield curves. The volume percent of these bottoms in the crude oil and its residues were used to calculate the evaporation losses suffered by the crude in order to yield the various residues. The results indicate that, although further refinements in technique are required, it is possible to calculate evaporation losses with an accept-able degree of accuracy through the use of this method."

Jan 1, 1960

By Mirian Mamani

Como resultado de la exploración por litio, hoy se conocen ocurrencias importantes (de hasta 3,000 ppm de litio) en la tobas de composición riolítica en la región de Puno, Perú. Para conocer el estado actual de las principales concentraciones de litio en rocas félsicas (granitos y riolitas), se ha compilado información geoquímica (>10,000 muestras) de varias fuentes en el territorio peruano. La distribución espacial y temporal de las concentraciones de litio muestra que los valores mayores a 300 ppm se encuentran en las rocas félsicas, riolitas del Oligoceno-Mioceno y monzogranitos del Triásico del trasarco, y también en los diques de sienitas nefelínicas (30-100 ppm); todas las cuales se ubican en la margen oeste de la franja de Sn, W, Mo. Los valores más altos (mayores a 600 ppm) corresponden a la región de Puno. Sin embargo, niveles de tobas retrabajadas del altiplano que fueron emitidos por las calderas volcánicas del trasarco y sedimentos que desembocan en el lago Titicaca muestran concentraciones de 100 a 400 ppm de litio. Además, las fuentes termales de Tacna y Moquegua contienen entre 10 y 50 ppm de litio, lo que indica que por debajo de los volcanes recientes existen sedimentos con litio. Finalmente, debe indicarse que el mayor potencial de litio (3,000 ppm) está relacionado con los minerales denominados como macusanitas.

Nov 30, 2018

"Desde 1950 en el Perú, el examen pre-ocupacional es un requisito para la inserción laboral dentro de la industria minera. Es por ello que la empresa se encargaba de la realización de la evaluación directamente. Posteriormente se designó dicha labor a un personal no facultativo, conllevando riesgos de salud futuros para el trabajador y por ende, a la producción de la empresa. En este sentido, el presente texto señala algunos de los aspectos de política preventiva de salubridad, donde sea el profesional médico, quien realice una promoción de salud y diagnóstico precoz de la enfermedad, protegiendo así la vitalidad del trabajador. Entre las principales funciones del personal médico a realizar tenemos: las contínuas visitas médicas al lugar del trabajador, desarrollar una permanente capacitación de actividades de higiene industrial, delimitar enfáticamente una orientación preventiva de su trabajo, etc. De otro lado, el trabajo muestra una descripción del formato médico (datos, historia ocupacional, antecedentes patológicos, sintomatología, examen clínico, inmunizaciones, clasificación de actitud) que debe considerar el examinador, para obtener un conocimiento conjunto del estado de salud del postulante y potencializar las capacidades del trabajador para la industria minera. De tal forma que se logra integrar en un solo documento médico, los resultados de los exámenes y se prescinde de la necesidad de contar con grandes archivos, facilitando el seguimiento de los casos."

Jul 20, 1957

By C. H. Tiernon

"This paper was' prepared to emphasize the part that coal washing tables can play in the development of many of the reserves of coking coals in Western Canada_ It covers a brief history of the development of the coal washing table through the present third-generation unit, which suspends from overhead steel beams and is driven by a counter-rotating gear mechanism. The design and operation of this unique table are covered in detail.An analysis of actual operating data is included, with explicit statistical breakdowns of the table products. The data used were actually produced by operating coal companies, and also produced by the United States Bureau of Mines while gathering data for a research investigation. Table feed capacity is discussed, as well as performance criteria and the parameters of relative table performance. Several typical table flowsheets are described, emphasizing the specific reasons for their use. The paper covers the past and present value of the table to the United States coal industry, and makes mention of the newest addition to the family of suspended, multiple-deck, counter-rotating, gear-driven, coal washing tables, the CONCENCO ""88"" Deister table."

Jan 1, 1973

By George C. Coupland

"THE PRELIMINARY EVALUATION of the orebodies was computerized for tonnages and grades on a 20- by 20-ft grid. The evaluation was based on drill-core intersections over 40-ft vertical projections coinciding with the proposed bench intervals, taking the deviations of the drill holes into account. The computer print-outs gave an ore distribution and evaluation bench by bench and indicated the areas of varying mineralization. The two orebodies have a combined length of 2,200 ft. and a maximum width of 600 ft. They strike almost due north, dip about 85 degrees east and rake to the north. The computer print-outs were used to design an open pit with an over-all waste to ore ratio of 2.58:1. At the outset, the waste to ore ratio was 4:1. The pit is tear-drop shaped, with the narrow end to the south, and at the surface is 2,600 ft long by 1,800 ft wide. Ramps are 100 ft wide, with a 10% grade. The south ramp is left-handed, starts at the southeast and will continue to the bottom of the pit. A second ramp on the west and north walls runs from surface to join the south ramp at 7 bench. This ramp will handle the total pit production when part of the south ramp, from 4 bench to surface, is lost due to the underground operation. Over-all wall slopes are 53 degrees, and are laid out to avoid prominent protuberances which could relax and become unstable and potentially dangerous (Fig. 1) ."

Jan 1, 1974

By Marvin E. Lane

Viburnum, located in the foothills of the Ozarks in south-east Missouri, is the site of a modern lead mining and milling operation. Two mines are currently producing a total of 5,000 tons per day and a third mine is in the final development stage, with full production scheduled for late this year (1964). These mines will supply the tonnage required to keep the Viburnum mill operating at a full capacity of 7,000 tons per day for many years. The efficient underground mining operation is completely trackless. Drill jumbos are used to break the ore in a room and pillar method of mining. Transloaders, or St. Joe shovels, and trucks do the loading and hauling. The Viburnum mill has a world-wide reputation as a most efficient operation. This is due to the extensive use of automatic process controls, and labour saving materials handling facilities. Introduction THE St. Joseph Lead Co., has operated lead mines in southeast Missouri for 100 years. These operations have been confined largely to the area called the

Jan 1, 1964

By H. E. Powell

This Bureau of Mines study describes two processes for recovering zinc, copper, silver, and iron from the magnetic fraction of a waste generated by the primary smelting of zinc in horizontal retort distillation furnaces. The laboratory-scale procedures include reduction melting to produce a high-copper iron and matte smelting to produce a copper-silver-iron matte and metallic iron. Zinc is fumed in each process and recovered as the oxide. Direct reduction melting yields a metallic iron high in copper and a small rich matte from the sulfur contained in the waste. The products of the second process are a matte containing essentially all of the silver, about 80 pct of the copper and 37 pet of the iron, and an iron-copper alloy containing all of the remaining copper. Extraction with metallic lead or sodium sulfate recovers essentially all of the copper from the molten high-copper iron and yields an acceptable foundry iron.

Jan 1, 1973

By G. W. Jones

In the course of experiments on the stabilization of acetylene gas by addition of other gases, notably hydrocarbons such as methane, propane, and butane, it was observed that large quantities of carbon black are produced during the explosion of acetylene or mixtures of acetylene with the, above hydrocarbons, the added hydrocarbon being essentially decomposed into hydrogen and carbon. It is known that in the complete absence of air acetylene explodes upon application of an intense ignition source at pressure above 5.9 p.s.i. gage. The same is true of mixtures of hydrocarbons and acetylene. However, the pressures necessary for explosion are considerably higher in the case of these mixtures and depend on the amount of added hydrocarbon. The present report contains data on gaseous products and the physical characteristics of the carbon black formed by explosion at elevated pressures of various mixtures of acetylene and hydrocarbons as well as other gases, such as hydrogen, helium, nitrogen, and carbon dioxide.

Jan 1, 1950