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By H. B. Jensen

STUDY of the thermal-solution process was begun by treating crushed oil shale in a small autoclave at temperatures of 700° to 950° F. The effect of temperature, reaction time, type of solvent, and richness of shale upon the amount of organic matter that was removed from the oil shale was thus determined. Following this orientation work a semicontinuous, bench-scale apparatus was built so that heated solvent could be pumped through a bed of shale under elevated pressure, thus removing the converted organic matter from the spent shale. After some operating experience had been gained, a continuous unit was constructed. This permitted treating a slurry of shale oil and pulverized oil shale at about 300 p. s. i. and temperatures of 750° to 850° F. for various retention times. Considerable cracking and polymerization of the shale oil were found to take place during the process. In an attempt to prevent this, a study was made of extraction of the shale in batch-type autoclaves under high partial pressures of hydrogen at total gas pressures of as much as 4,300 p. s. i. at 850° F. The thermal-solution process was found to convert over 90 percent of the organic matter in oil shale to oil and gas. The highest yields of gas and oil obtained without hydrogen pressure were equivalent to 119 weight-percent of those obtained from the same shale by Fischer assay. With a high partial pressure of hydrogen, yields equivalent to 126 weight-percent of Fischer assay were obtained. However, the oil produced by thermal solution has a higher boiling range than that obtained by other retorting methods, particularly so if the thermal-solution process is used without a high partial pressure of hydrogen. Nondistillable oil (all benzene-soluble material that would not distill under 2 mm. Hg absolute pressure without cracking) equivalent to over 100 percent of the organic matter in the shale was obtained without hydrogen pressure in the system. When the process was carried out under hydrogen pressure, the yield of nondistillable oil amounted to 60 to 70 weight-percent of the organic matter. Part of this heavy material is formed partly by polymerization and condensation of the shale-oil solvent used. These reactions, as well as cracking of the solvent to form gas and a carbonaceous deposit on the shale, are unfavorable features of the process.

Jan 1, 1953

By J. Baz-Dresch

A custom-designed shotcrete system, consisting of an 8-m3 (10-yd3) transit mixer and a shotcrete spray boom carrier, is used bya 2-man crew to transport and place up to 25 m3 (32 yd3) of steel-fiber reinforced, dry, silica fume shotcrete per II-hour shift. Shotcrete is custom blended by a local supplier and delivered predampened. Mix design and quality control is performed with a computer program that develops and graphs a properly balanced mix based upon the materials sieve analyses.

Jan 1, 1991

By J. Armanet

THREE MINING colleges are maintained in France; the École Nationale Supérieure des Mines, of Paris; École Nationale Supérieure des Mines, of Saint Etienne; and the École Supérieure de la Metallurgie et des Mines at Nancy. Besides graduates of these schools, a few graduates of the École Centrale des Arts et MIanufactures and of the École Polytechnique are employed as ]nine managers or engineers; however, most of the latter have taken a graduate course at one of the mining schools.

Jan 1, 1939

By Sherwin F. Kelly

"THE TITLE I have chosen is certainly not one of those self-explanatory ones. I shall endeavour to make its significance clear during my remarks but, in the hope of minimizing that inevitable exodus which follows a good lunch such as this, I am going to withhold the final key to its meaning until the very last sentence of this talk.Some explanation is due at the beginning, however, so for those of you unfamiliar with Spanish I will explain that casa means house, or home. The casa about which I am going to talk necessitates a wide .and generous interpretation of the word, because I am using it to indicate principally that portion of the North American continent which is the home, in the western hemisphere, of British and American ideals of justice and freedom, the dignity of the individual and his right to exercise private initiative .and engage in private enterprise. In a wider sense, I am including the entire western hemisphere, which may yet stand as the last bulwark of political and industrial democracy.As for the treasures of which I am about to speak, may I remind you that there are no• material treasures but those derived from the earth, and they are derived by one of two processes, -mining and farming. These two fundamental industries are the basis, and the sole material basis, of our welfare, our wealth, our very existence. From farming, whether it be farming of the land. or farming of the sea, we obtain the food to keep us alive, healthy and able to work."

Jan 1, 1955

By R. L. Miller

"Why should we care about diesel quality amidst the complexity of mining for minerals? Mining companies use a large amount of diesel fuel in their worldwide operations, both for moving ore from the mine to the processing mills or transportation hubs, and to generate power for onsite processing. This creates a large carbon footprint and poses both environmental risk with the production of emissions, and public perception of how those companies do their business as stewards of the environment while incurring a huge fuel expenditure. To improve diesel quality and create incremental value and greater environmental stewardship, the opportunity is broken down into several segments: 1. Mining industry diesel consumption 2. Fuel quality issues 3. Impacts on operations, economics, and emissions 4. Potential solutions 5. How improved fuel quality saves fuel expenditures 6. Economics of improved fuel quality 7. Recommended testing process 8. Fuel quality analysis checklist MINING INDUSTRY DIESEL CONSUMPTION The average grade of mined Australian ore bodies has halved, while the waste removed to access the minerals has more than doubled over the last 30 years, thus increasing energy consumption by 70%, (http://eex.gov.au/industry-sectors/mining/). Energy consumption and intensity in mining and mineral processing is rising at around 6% per annum. The mining industry is a huge consumer of diesel fuel worldwide, and the SRS Rocco Report of 4 August 2014 gives a better picture of recent trends. To better understand the reasons to reduce both fuel costs and consumption, we need to compare metrics on the amount of diesel consumed per each ounce of gold produced over the last decade. The rate of diesel consumption in gallons per each ounce of gold produced for the top five worldwide gold producers has doubled in the last 8 years from 12.7 gallons per ounce in 2005 to 25.8 in 2013 as shown in Figure 1 below.This is caused by 1) lower ore grades requiring more hauls to get same amount of finished gold product, and 2) haul trucks moving ore from deeper sources in open pit and underground mines. For one large multi-national gold mining company, the 2005 waste rock / production ratio was 52 metric tons/gold ounce; by 2013 that ratio had grown to 113 metric tons/gold ounce per the same SRSrocco 4 August 2014 report. Using the metrics above, the top 5 gold miners used over 591 million gallons of diesel fuel in 2013. The cost of diesel in dollars per ounce of gold has increased from $30.48 in 2005 to $101.14 in 2013, an annual appreciation of 16.2% as shown in Figure 2 below."

Jan 1, 2017

By H. O. HOPMAN

(Canal Zone Meeting, November, 1910.) I. INTRODUCTION. THE substance of this paper was prepared for the Seventh International Congress of Applied Chemistry, held in London, May, 1909, under the title, Some Developments in Blast-Roasting. In the absence of the author, a -short abstract of the paper was read, and the abstract only will appear in the proceedings of the congress. The present paper has been partly rewritten and considerably enlarged by information gained since the original was prepared ; also some illustrations have been added. Blast-roasting' is a generic term for the process of forcing air through finely-divided. metallic sulphide with the object of roasting and agglomerating in a single operation. At first the process was confined to a galena-concentrate ; lime, limestone, or gypsum was added, to serve both as a diluent to keep separate the particles of galena that they might be thoroughly oxidized, and as a flux that the partly-roasted ore might be agglomerated by the formation of some slag. Later it was extended to treat other metallic sulphides. The leading processes were the Huntington-Heberlein and the Savelsberg of Europe, and the Carmichael-Bradford of Australia. In the United States and Canada, the Huntington-Heberlein process has found application in some instances with galena-concentrates, for which it was originally intended; but this class of ore is not often treated alone, hence the process has had to be modified to suit conditions. The Savelsberg process has been transplanted to this country in about its original form. The Carmichael-Bradford is not used at present. The changes called for in the Huntington-Heberlein process to adapt it to the class of lead-bearing ores usually smelted have been the 1 A. S. Dwight, Engineering and Mining Journal, vol. lxxxv., No. 13, p. 649 (Mar. 28, 1908).

Jun 1, 1910

By Roberto de Moraes

Lunar construction faces unique challenges arising from the nature of regolith and megaregolith. Unlike terrestrial soils shaped by weathering, lunar regolith is composed of angular, poorly sorted particles produced by impacts, with bulk Density, strength, and trafficability varying sharply with depth and terrain. Boulder fields, floaters, and talus aprons add further complexity, disrupting excavation and mobility. Apollo missions documented these conditions through drive-tube samples, trenching, penetrometer data, trafficability tests, and seismic profiling, but the results remained as datasets rather than a unifying classification. This paper introduces the LRC (Lunar Regolith Classification) Framework and the Overconsolidation Ratio applied for the Moon (OCR*), the first contractor-ready system to organize Apollo-derived trends into excavation demand zones (L1–L5). LRC is explicitly a classification, not a stratigraphy: depth ranges are indicative and require in-situ verification before use. Each zone is defined by bulk density and strength ranges, field proxies (bootprints, trench stability, auger torque, seismic contrasts), and corresponding excavation implications. Worked examples from Apollo 15 (mare), Apollo 16 (highlands), and Apollo 17 (pyroclastics and talus) demonstrate how observed data translate into LRC zones. These cases show that LRC captures both systematic depth trends and sharp local heterogeneity. The framework standardizes excavation planning for landing pads, haul roads, berms, foundations, and tunneling trials, while converting floaters from hazards into resources. LRC thus provides a common language for lunar construction. Rooted in Apollo evidence but designed for Artemis verification, it is proposed as a living standard; a reference framework to guide site preparation, excavation, and risk management in the next phase of lunar development.

Feb 22, 2026

By J. C. Kingston

Introduction The sliding-form method of erecting concrete structures was first devised and used in the early part of this century by the Sante Fe Railroad Company for the erection of a grain elevator at Santa Fe, New Mexico. A somewhat related principle has been employed for a number of years in shaft lining work and, to our knowledge, was perfected in Butte, Montana, but until the building of the concrete headframe at the Jeffrey mine of the Canadian Johns-Manville Company, Ltd., at Asbestos, Que., the method, as applied to surface structures, was quite foreign to the mining industry in Canada. The current shortage and cost of structural steel shapes has no doubt contributed more than any other single factor to the investigations that have led to the use of reinforced concrete as a headframe building material. Mining men in western Quebec and northern Ontario have shown a great deal of interest in the design and construction of the headframe at the East Sullivan mine in Bourlamaque township, Que., and we have had many queries regarding the methods used and, in particular, for an explanation of the sliding-form principle. This article is written in an attempt to set forth the conditions which were to be met; to explain the construction methods used, and to discuss the economy of concrete headframes as compared with the conventional steel structures with which the mining fraternity is familiar.

Jan 1, 1949

By H. L. Riley

This report describes the methods and equipment used by the Watauga Stone Co. to drill and blast limestone in a two-level quarry, and to crush, screen, blend, and load this stone. Power requirements per ton of stone produced are reported. The personnel requirements for individual phases of the operation are tabulated in man-hours per ton of stone produced.

Jan 1, 1963

By Gurubasayya Swamy

This paper presents the performance study of sag mill in the processing of gold ore. Deterioting ore grade and high demand of metals has tremendously influenced the SAG mills. Today?s high capacity Semi-autogenous grinding (SAG) mills expand vast amounts of energy and in doing so consume tons of shell liners and steel balls, while processing ore. Semi-autogenous (SAG) mill performance is influenced by ball charge, feed properties, shell, grate, and pulp lifter design. In the performance study of SAG mill, based on the results obtained it can be observed that SAG mill performed better at feed size +4 inch and grinding media consumption 0.90kg/mt. In the present study the effect of crusher bypass on SAG mill performance, an immediate drop of throughput ranging from 10-20tph is observed. Keywords: sag mill, pulp lifters, grinding media, energy, consumption, throughput

Sep 1, 2012

By Ben Habermann

"The object of the work described in this paper was to increase the understanding of the relation that capillary pressure of a rock, hydro-dynamics, and accumulation of oil in stratigraphie traps have to one an-other. The hydrodynamic oil-water tilt equation is derived by considering the two vector gradients involved: (1) buoyancy of oil in water and (2) hydraulic gradient.Recent theories show the necessity for oil to have a continuons phase in the reservoir rock in order to mi-grate; this fact applies to hydro-static as well as to hydrodynamic conditions. Hydrostatically, the displacement pressure of the rock deter-mines the amount of oil that can be trapped behind a permeability barrier. If the buoyancy of oil in water exceeds the displacement pressure, oil will migrate up-dip; an oil trap will be formed where displacement pressure is greater.In stratigraphie traps the pressure drop caused by moving water is positive when its direction is down-dip, helping accumulation; and it is negative when its direction is up-dip, forcing the oil into the tighter section of the reservoir. Theoretically, pro-vided we have data such as: (1) the displacement pressure of an up-dip permeability pinchout, (2) density difference between the oil and water in place, and (3) the direction and magnitude of the hydrodynamic gradient (if any), the possible extent of a stratigraphie oil accumulation down-dip can be predicted.To test the above theory sample cores from three wells in the Denver Basin were analyzed and the oil column that could be held under hydro-static conditions was calculated. After the hydrodynamic influence was considered, the results were compared with actual field data.The significant fact shown by this investigation is that the calculated oil column in one reservoir very closely approximates the actual extent of the oil column in a well. Also in accordance with the theory, the capillary pressure caused by the buoyancy of the oil column exceeded the measured displacement pressure on core samples from another productive field. For very tight shaly sand and questionable oil shows, the interpretation of data is very critical, as shown by experiments on core samples from a third field."

Jan 1, 1960

By Christian Maguire

Tunnel contracts in New York have in recent years had few bidders with the bids received being much higher than anticipated. Since 9/11, security has become a key issue in planning key infrastructure projects in New York. This is especially true in the case of large water supply tunnels. Striking the right balance between cost and security was the major factor in determining the best configurationfor the Kensico-City Tunnel. This paper outlines the efforts made to determine realistic probable bid costs for the tunnel contracts, and the innovative approaches taken to deal with security issues.

By Kiyoshi Shibata

A new assessment model has been proposed for metal production and its recycling system. The model consists of three processes, smelting of ore, cascading and upgrading of metal scrap. The present approach is to assess the total energy consumption of the system, by introducing two equations for describing the relationships between critical impurity content and the mass of production or scrap recycling. The total energy consumption in the system can be described as a function of recycling rate and performance of the upgrading process. The present model suggests that the impurity removal efficiency and yield in the upgrading process are essential to reduce the energy consumption in the systems. Especially, such points should be explicitly controlled in recycling of aluminum. The potential capability of this model was also discussed by obtaining several quantitative information required for the process design and the operational control of beneficial recycling of metals.

Jan 1, 1998

By M. A. Reyes, L. Yan

Heat and humidity buildup within refuge alternatives (RAs) may expose occupants to physiological hazards such as heat stress. The Mine Safety and Health Administration (MSHA) regulations require RAs in underground coal mines to provide a life-sustaining environment for miners trapped underground when escape is impossible. RAs are required to sustain life for 96 h while maintaining an apparent temperature (AT) below 95 °F (35 °C). The National Institute for Occupational Safety and Health (NIOSH) tested a 10-person tent-type RA, a 23-person tent-type RA, and a 6-person metal-type RA in its underground coal mine facilities to investigate the thermal environment over a 96-h period. The test results showed that mine air and mine strata temperatures surrounding an RA occupied by simulated miners (SMs) increased over the 96-h test period. The test results suggest that RA manufacturers should consider this increase in temperatures when calculating and evaluating RA components during surface and laboratory tests. The findings can equip stakeholders with additional considerations for calculating the interior heat and humidity temperature profiles for occupied RAs not tested in situ

Nov 22, 2019

By R M. Arellano, D M. W Harney, M Makhuvha

Mineral resource and ore reserve estimates are founded on two sources of data: tonnage and grade. The tonnage is a product of volume and density; both of which are estimates. Density impacts numerous operational factors, which include, but are not limited to, mine design, mine planning, equipment selection and operational performance. Hence, density is a significant parameter and its determination requires similar care as the measurement of grade. Selecting an appropriate method to determine density, and ensuring its rigorous application, thus reduces risk and can improve operational performance, which in turn increases profit margin.Different Anglo American sites use a variety of practices and protocols to determine density, which is highly dependent on the physical characteristics of the orebody, local conditions and historical practices. Also, individual sites sometimes execute the same method in a slightly different way, which may also affect the outcome of the measurements. In order to gain a better understanding of how density is determined at Anglo American projects and operations, a review of these techniques was undertaken. The objective of the study was to identify and share good practices across the company, as well as to look for improvement opportunities, where applicable. Ten different methods of measuring density, applied to nine different commodities, were identified and described. An additional technique was recently developed by Anglo American Technical Solutions. The core pycnometer is a large gas displacement pycnometer capable of measuring density at high accuracy on full pieces of intact core.This paper provides an overview of methods used to determine density within the Anglo American Group, including quality control and quality assurance aspects. It is not the purpose of this paper to identify a preferred method, but to highlight the importance of choosing the best suited practice for a project or mine site. In addition, a case study comparing two different density determination methods applied to the same rock samples from the Los Bronces Copper mine was undertaken and the results of that study are presented here.Selecting the most appropriate method to determine density and comparing results from two or more techniques against each other, together with other suitable quality control procedures, is considered to be of utmost importance for all mining operations and exploration projects.CITATION:Makhuvha, M, Arellano, R M and Harney, D M W, 2014. Determination of bulk density in Anglo American plc, methods and impacts, with a case study from Los Bronces Mine, in Proceedings Ninth International Mining Geology Conference 2014 , pp 85–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By W. T. Westbrook

This Bureau of Mines report contains methods for analyzing iron are for total iron, ferrous iron, metallic iron, silica, manganese, aluminum, calcium, magnesium, phosphorus, titanium, carbon, sulfur, moisture loss, and ignition loss by wet chemical methods. Some are modifications of standard umpire methods; others have been developed by the Bureau of Mines to provide a com-bination of speed and accuracy. They are suitable for a high volume of samples and/or control situations, and for situations in which instrumental results must be verified. These methods have been used to analyze taconites, native ores, some foreign ores, and metallurgical products.

Jan 1, 1975

By Ricardo Oliveira Gallart de Menezes, Claudio Gerheim Porto, Reiner Neumann

This study presents the results of the mineralogical characterization of Ti-Zr ore from the Jiboia deposit, located in the municipality of Brejo Grande, Sergipe State, Brazil. The goal is to identify the main Ti, Zr, and REE carrier phases in the different particle size fractions in order to subsidize the development of a cost-effective processing route for the production of heavy minerals concentrate. The mineral resources are estimated at 31.5Mt @ 3.5% of total heavy minerals (THM) for the Jiboia Ti-Zr deposit, of which 5 Mt @ 3.39% THM were classified as measured and indicated. The mineralogy of the heavy mineral concentrate recalculated to 100% is represented by 22% pseudorutile, 20% ilmenite, 15% zircon, 5% rutile, 2% monazite, and 36% gangue. The ore minerals are preferably concentrated in the 150 × 53-μm granulometric fractions, which represents 80% of the THM and only 27% of the ROM (Run-of-Mine) ore. Therefore, by cutting the ore to 150 μm, it is possible to discard 73% of the ROM mass and recover 80% of the THM, including 100% of the zircon and monazite which are the most valuable minerals present in the heavy mineral concentrate. The global recovery of THM starts to decline rapidly in the fractions finer than 106 μm and the mass disposal (tailing) does not follow in the same proportion. Higher zircon contents in the concentrates of the fractions finer than 150 μm imply a significantly lower recovery of heavy minerals like ilmenite, pseudorutile, and rutile that make the fractions coarser than 150 μm.

Jan 9, 2024

By Patty Simpson, Sarah Benson

In an effort to improve consistency across the nuclear industry, over the past 10 years the Canadian Standards Association has developed a series of standards related to environmental management at Class 1 nuclear facilities and uranium mines and mills. Canadian uranium mines have been required by the Canadian Nuclear Safety Commission to align their existing monitoring programs with these standards. Orano’s McClean Lake Operation’s monitoring program, which was originally presented in the Environmental Impact Statement in 1991, has evolved through regulatory change, new scientific understanding, additional projects, and experience into a comprehensive set of monitoring requirements for effluent, groundwater, air emissions, and the receiving environment. The exercise of aligning the existing practices with the standards provided an opportunity to review and rationalize the entire program. To document the process the original “Environmental Monitoring Program Design Document” was restructured and developed as both a repository for historical information and monitoring rationalization, and also to be a living document describing on-going studies and supplementary work that are outside of the regular environmental monitoring program and may justify future changes to the program.

Jan 1, 2020

By Bao Xiancheng

Jinlong's copper flash smelting process started up in April 1997. In the early days of production, lots of equipment and process problems were encountered. But, through continuous improvements in equipment and operation, the designed productivity was reached two years later and the smelting operation has been greatly upgraded since then. After more than 4 yew of production, we have made great achievements, such as increasing the flash furnace availability, significant improvements in operation control, optimization of concentrate burner's structure and operation, and smooth operation of the whole smelter. This paper outlines Jinlong's operational achievements made after commissioning, and discusses problems that were encountered and their countermeasures. Operational experience is also summarized

Jan 1, 2002

By J. Peterson

A review of blast designs and improved blasting practices at the Ekati??Diamond Mine is presented along with the results of three blast-monitoring experiments. Blast monitoring was undertaken to investigate blast damage mechanisms in the mine's well jointed rock mass. Rock mass damage caused by production, pre-shear and wall control blasts was measured. Ekati??uses 270mm holes for production blasting, and 165mm holes loaded with a decoupled charge for pre-shearing. The production blasts are loaded with bulk emulsion / ANFO blends. The mine plan involves using 30m double benches. A 30m high pre-shear is drilled and blasted prior to the production blasting that is done with sequential 15m benches. This paper summarizes the monitoring equipment and data gathered to date.

May 1, 2001