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By V. L. Eardley-Wilmot

Diatomite as prepared for the market is a fluffy, white powder, remarkably light in weight-it weighs only 10 to 15 pounds per cubic foot, or one-tenth as much as sand. Being extremely porous and inert, it is in large and increasing demand for insulation and filtration purposes, as general filler, and for many other uses. Structure Structurally, diatomite is quite different from any other known commercial material. It is composed of myriads of microscopically small, siliceous shells of diatoms which belong to a group of flowerless aquatic plants called algae. When these plants die, the siliceous remains sink to the bottom of the water and form beds of diatomite. Over 8,000 species of diatoms are known, named, and tabulated. The intricate scroll-work and patterns on many of these are one of the marvels of nature, and yet so small are they that from 40 to 70 million separate diatoms may be contained in one cubic inch of material. However, the size and shape of these diatoms, which vary greatly (compare Figures 5 and 6), have an important bearing on the commercial use of the diatomite. The diatoms in the majority of the known deposits are so typical of that deposit that, after a micro-examination, an expert can usually tell not only from what part of the world, but also from what particular deposit, the sample has come.

Jan 1, 1931

By H. N. Smith

IN 1944 the Congress passed the Synthetic Liquid Fuels Act that authorized the Secretary of the Interior, acting through the Federal Bureau of Mines, to conduct basic research and construct and operate demonstration plants to produce synthetic liquid fuels from coal, oil shale, and other substances. As a basis for the oil shale investigations to be undertaken in this country, the progress of foreign countries in developing and using oil shale as a source of liquid fuels was studied by the technical missions of the Federal Bureau of Mines. Oil shale mines, retorting plants, and refineries were visited; geological information on the nature and occurrence of the foreign oil shales was obtained; and samples of the oil shales were collected where possible. Samples collected by these missions or acquired by other means came from Australia, Brazil, Canada, France, Manchuria (China) , New Zealand, Scot-land, Spain, Sweden, Thailand, and Union of South Africa. These countries represent a large part of the locations where oil shale developments have taken place. The major omissions are the Estonian, German, and Russian developments.

Jan 1, 1959

By Orlando C. Gaspar

The textures of the ores, the fine mineral intergrowths, the complex distribution of the deleterious minor elements, and the low base metal contents in some ore types, pose many technological problems to the beneficiation of the volcanogenic massive sulphides occurring in the Iberian Pyrite Belt. In particular fine intergrowths of the base metal sulphides with pyrite impose extremely fine liberation sizes (Kao=15 to 25um). The mineralogical, textural and metallogenic studies have provided an understanding of the distribution of vertical and lateral metal zoning in the ore bodies. Mapping of the ore types, carried out by mine geologists, and the metal zoning patterns computed from data base have shown that ore types are distributed as ore lenses, and that vertical and lateral base metal zoning exists in several orebodies. Since ore processing efficiency is affected by ore textures, and because the same mineral often shows different textural features, a relationship between the textures of the feed ores and those of the middlings must be established for all ore types defined at the deposit scale. For supplying, on time, the information needed for the optimization of the concentration processes, empirical methods of determining the mineralogical and textural characteristics of the several ore types have been developed.

Jan 1, 1995

By J. Convey, S. L. Gertsman

"THE EXPANSION of steel capacity is seldom spectacular. It may be for this reason that the remarkable progress made in Canada has not been generally recognized. In 1950, Canada's output of steel ingots amounted to 3,270,000 tons ( l ), which is a ll8 per cent increase over the tonnage produced in 1939. It can therefore be readily seen that Canada's growth curve for steel production is climbing at a rate paralleling her growth as a nation. It is by no means •an exaggeration of its importance to consider the steel industry as the cornerstone in the economic structure of Canada's manufacturing activities. From the humble diaper pin to the giant members of massive bridges, fortifications, and other steel structures, steel accompanies us as a necessary and inescapable companion in our journey through life. The Age of Steel has a literal meaning, and refinements in the manufacture of the products of steel are adapting it to more and more varied uses as time passes.The integrated iron and steel works of Canada fall into two natural geographical divisions. One has its base on the Great Lakes and draws its supply of •coal and some of its ore from the United States. In this division lie the works of the Algoma Steel Corporation, at Sault Ste. Marie, at the junction point of lakes Huron, Superior, and Michigan; and the works of The Steel Company of Canada, at Hamilton, on lake Ontario."

Jan 1, 1952

By H. Chu

Selective Agglomeration experiments carried out to clean ultra-fine coal are examined. Effect of feed size, pulp density, coalescing agent dosage, and mixing intensity and duration on the kinetics of agglomeration are principally evaluated. A computer coded population balance model governing agglomerate size distribution and composition utilizing coalescence and breakage mechanisms is developed. Model calibration, verification and extension are analyzed.

Jan 1, 1987

By James W. Cameron

DESPITE the fact that, after oxygen and silicon, aluminum is the most abundant and widely distributed element in the earth's crust, it is, commercially, a modern metal. Attempts were made by Sir Humphrey Davy and other chemists to decompose alumina, the oxide, into its elements, but with unsatisfactory results, and it was not until 1827 that Wohler succeeded for the first time in isolating the metal in pure form. Some thirty years later, commercial production of aluminum was started in a plant near Alais, France, using a process developed by Deville which was a modification of that of Wohler. It was not, however, until around 1886 that possibilities of low-cost production were realized. Hall and Heroult discovered, independently, the now famous process for extraction of aluminum by the electrolysis of alumina (Al,O,) dissolved in fused cryolite. This discovery, with its subsequent effect in reducing the price of the metal, was perhaps the greatest single factor contributing to the remarkable growth of the aluminum industry. But only in the years following the Great War did aluminum begin to attain equal importance in many fields with other non-ferrous metals. Numerous factors, political and economic, in the past decade have had a profound effect on the industrial history of the metal. At present, systematic substitution of aluminum for other base-metals is proceeding at a rapid rate in such countries as Germany and Italy with a view towards 'economic self-sufficiency'. Quite naturally, ?the economic depression started extensive research and experiment in various industries in an attempt to improve efficiencies and lower costs. Partial answers have been found in the extended use of aluminum and its alloys. Even against the background of tremendous technological advance that has marked the past fifty years, the rise of the aluminum industry must necessarily stand out conspicuously.

Jan 1, 1939

By M. Pope

By 1950, packaged oil and gas fired boilers were on the market for capacities up to 30,000 lbs./hr. By 1962, capacities were up to 100,000 lbs./hr. and even higher when separate heat traps (economizers and air preheaters) were attached to the boiler packages. During this period, complete packaged coal fired boilers were developed into the 10-15,000 lbs./hr. range. Oil and gas fired plant designs became very compact, "basementless", and far: less costly than the coal fired plants of any capacity. Coal fired plants remained large and expensive, required field erection of boilers and required basements. With the spectacular strides made in automation, oil and gas plants became far less costly to operate, requiring only the part-time attendance of a single operator. Some advances were made in coal fired plants, but not to the degree attained by the fluid fuel competition.

Jan 1, 1965

By S. R. Rannels, D. E. Rannels

"I. IntroductionThe alveolar surface of the lung is covered by two populations of pneumocytes, type I and type II epithelium. The type I cell, which accounts for most of the alveolar surface area and provides a highly specialized barrier for gas exchange (Rannels et al., 1991), is poorly understood. Although approaches to type I cell purification have been discussed, they have not been applied widely because of the lack of phenotypic markers to monitor isolation procedures (Dobbs et al., 1988; Danto et al., 1992). In contrast, the type II cell has been studied extensively, largely because of the development of reliable procedures for its isolation and primary culture. Investigations based on the use of purified populations of cultured type II cells have provided convincing evidence to support a role for the pneumocytes both in the maintenance of normal lung function and in the response of the lung to injury (for review, see Rannels and Rannels, 1989).While type II cells can be isolated by a variety of approaches, the protocols used most commonly are modifications of the gradient method of Dobbs and Mason (1979) or of the panning method of Dobbs et al. (1986). Purification of the cells based on density gradient centrifugation is reliable and consistent, with yields of 30 to 40 X 106 type II cells per rat of 230 g body weight. Isolation procedures applied to a minimum of three to four rats provide the best results, as lower cell yields are common with the use of fewer animals. The protocol below is designed to obtain a maximal cell yield from the lungs of six rats.II. Materials and InstrumentationMaterialsCalbiochem: DNase I (Cat. No. 260912); Corning: culture flask, 75 cm2 #25115; Costar: culture plate, 24-well #3424; disposable serological pipette #4101; Elastin Products Inc: elastase #E-134; Falcon: cellulose nitrate membrane filter, 0.22 µm, #7105; conical tube, 50 ml, #2070; culture dish, 100 mm, #3003; culture plate, sixwell, #3046; Fisher: BaS04 , #B68-500; NaCl, #5271-3; NaHC03 , #5233-50; Fort Dodge Laboratories: pentobarbital, #1206-lE; Gibco: Dulbecco's minimal essential medium (DMEM), #430-1600EC; Hanks' balanced salt solution (HBSS), #310- 4185AG; Joklik's modified Eagle's medium (JMEM), #410-2300EC; HyClone Laboratories Inc: fetal calf serum (FCS ), # A-1115-L; I CN Biochemicals (Flow Labora tories): amphotericin B, #16-723-48; newborn calf serum (NCS), #29-121-54; try pan blue, # 19 5 5 32; Na/gene: Erlenmeyer flask, # 100-4116C; Pharmacia: Percoll, #17-0891-01; density marker beads, #17-0549-01; Sigma: gentam1cm sulfate, #G3632; penicillin/streptomycin, #P3539; trypsin inhibitor, #T9128; Tetko: HC- 160 nylon mesh, #3-160-53."

Dec 1, 1995

By E. C. W. Perryman

BEFORE describing the methods used for fabricating uranium into various shapes and sizes it is necessary to illustrate briefly the unusual conditions under which uranium has to operate when used as a fuel element in a reactor. During reactor operation, for every fission that occurs two atoms of intensely radioactive fission products are produced together with two or three neutrons. The neutrons that are ejected possess several m.e.v. of energy and when one of them strikes an atomic nucleus, that atom acquires up to 105 e.v. of kinetic energy. This is large enough to displace the atom from its lattice position and send it shooting through the crystal, displacing other atoms out of their lattice positions. The net result is that a large number of vacancies and interstitial atoms are formed within the crystal lattice which sometimes have profound effects on the physical and mechanical properties of the material in question.

Jan 1, 1957

This consolidated index covers all publications of the Institute for the years 1926 through 1935. The following list indicates subjects of volumes and gives numbers or abbreviations used to designate them. TRANSACTIONS VOLUME *G26. Petroleum Development and Technology in 1925 (Published in 1926). *G26. Petroleum Development and Technology in 1926. *E27. Institute of Metals Proceedings. 73. Nonferrous Metallurgy, Milling and Concentration, Nonmetallic Minerals, Institute of Metals and Iron and Steel. [ ]

Jan 1, 1936

By R. J. Sheets

"INTRODUCTION What is the primary responsibility for geo-engineers in mining? Early in my career, I was asked this question by an experienced engineer. After explaining some various tasks, I was informed that the main responsibility was to monitor. Although this proved true for many cases, I came to understand that monitoring is merely one means to achieve the primary responsibility of a geo-engineer – ensure the safety of all personnel. The potential for groundwater to impact stability allows this responsibility to be shared with hydrogeologists as well. Inherently, we monitor to identify risks; we analyze designs and develop models to mitigate risks; and we are provided opportunities to explain to supervisors the geo-risks to personnel and mine plans that will result from particular courses of action. A couple years ago, I took an opportunity to share experiences from the first several years of my career as a geotechnical engineer with junior geo-engineering staff within my company. The intent was to share situations that were a part of my development, so they could learn and understand their responsibility to the safety of all personnel. Similarly, the purpose of this paper will be to share these thoughts with new geo-engineers in the industry in order to help prepare them for the challenges they will face. WHAT IS OUR PURPOSE? A senior hydrogeologist shared an experience that occurred in their career. The experienced hydrogeologist had spent some time with the hydrogeology staff, most of them relatively new to the mining industry, to understand how they viewed, and carried out, what they perceived as their responsibility at an active mining operation. After a couple months of observing and mentoring, the senior hydrogeologist met with everyone and posed the question above. I am sure that most junior geo-engineers would start explaining different tasks or projects that they must complete. The list would include monitor groundwater levels, track slope movement, evaluate designs, build models, oversee drilling programs, etc. These individuals did as well their supervisor. After going around the room allowing each individual to answer, the experienced hydrogeologist provided them the real answer to the question: SAFETY. If you examine the root intent of nearly every responsibility geotechnical engineers and hydrogeologists have, it is to apply our professional skills to ensure the safety of our workforce. When the objective of safety from the geotechnical and hydrogeology disciplines is achieved, inherently accomplishing the mine plan should follow suit, or it should significantly minimize the impact by gravity or groundwater. The objective of a hydrogeologist is to ensure the soil or rock around an open pit or underground mine is dewatered; this specific objective will reduce pore pressures which could lead to a possible ground failure. They ensure a working bench/UG level is dry, so operations are not dealing with adverse conditions while mining. A geotechnical engineer is expected to use all available information and engineering judgement to provide design recommendations, so that the mine will not catastrophically fail. Additionally, they will implement the monitoring systems to identify hazards in advance in the event that the design is flawed and people need to be evacuated. We all know that safety is important to everyone; however, our particular set of technical skills play a significant role in ensuring the safety of a large portion of the global mining workforce."

Jan 1, 2018

By AIME AIME

ON THE occasion of the eightieth birthday of Captain Robert W. Hunt, the Iron and Steel Committee of the Institute, desiring to commemorate the great contributions made to the steel industry by Captain Hunt during his long career, conceived the idea of a Hunt Medal to be awarded annually by the Institute for meritorious contributions to the art of making steel. The project was received enthusiastically by all to whom it was proposed, especially by Captain Hunt's partners and employees who considered it their right, and asked for the privilege of -. - raising the necessary funds within their own circle. This was agreed to, and the Institute has received from them $7500 as an endowment fund to provide an annual award, and $1000 for the expenses of providing of medal.

Jan 1, 1920

Newcrest Mining Limited (NML) owns and manages the Ridgeway Gold Mine (RGM) located outside Orange in the state of New South Wales. RGM is a new underground sublevel caving (SLC) operation that is ramping up production to 4 Mtpa. The success of the SLC method at RGM is strongly influenced by production drill and blast practices. Distinguishing features of the Ridgeway SLC operation include choke blasting against broken rock, drawpoint brow preservation, loading of blastholes with different in-hole bulk emulsion densities, precharging of production rings and routine drawpoint fragmentation assessment. These areas are described in the context of RGMÆs required blasting objectives, production drilling and charging activities and innovative practices.

Jan 1, 2002

By R H. Knight

Production mine geology must be accurate and efficient in order to reduce risk and ensure that ore value and mining operation revenue are maximised. Present grade control practices are commonly based on outmoded and inaccurate 2D geological mapping techniques where spatial relationships are estimated by eye, sketched by hand and projected to arbitrary reference planes. The 3D mapping approach outlined in this paper integrates 3D photogrammetric imagery with implicit modelling techniques to enable more accurate grade control and reconciliation in underground mines. High-resolution stereo photographs are taken of daily ore development headings. Ore contacts are traced directly on a 2D face photo using a stylus and rugged tablet. Area-weighted face grades are estimated and calculated on mapped 2D face planes. In the office, a 3D photorealistic mesh is processed and georeferenced. 2D face mapping data is transformed into its actual 3D location and true 3D mine mapping is performed by digitising oriented 3D polylines representing ore contacts and other geological features directly onto the image surface. Three-dimensional spatial relationships are fixed, eliminating the projection error of traditional 2D methods. Ore envelope and waste solids are modelled within the closed, drift-round mesh. Volume-weighted ore envelope and round grades, as well as round volume and tonnage, are calculated. Ore/waste classifications, grade, tonnage and per cent dilution are quantified per round, visually assessed in 3D and reconciled with short- and long-term models on a daily basis. Updated geological continuity models provide geological guidance in development headings under geological control and accurate 3D structural and form-line mapping improves definition drilling and stope planning. Three-dimensional imagery provides a permanent detailed survey and geological record of mine workings that can be revisited virtually to reinterpret geological ore controls in light of new observations and insights. In addition images can be used to monitor daily production performance, create training scenarios for miners, engineers and geologists and prepare management presentations. This approach adds value to underground mines by improving the accuracy and efficiency of mine geology practices. The method is particularly effective in mines with visually distinct and geometrically complex orebodies, such as those in the Balmat zinc mine located in New York State, USA, which are used to illustrate the method.CITATION:Knight, R H, 2017. 3D mine mapping – improving grade control and reconciliation in underground mines using photogrammetric imagery and implicit modelling techniques, in Proceedings Tenth International Mining Geology Conference 2017, pp 203–212 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By J. W. Miller

This report deals with upgrading of the coal reserves of Raleigh County, VI. Va., to metallurgical standards. The data on samples herein correctly show the characteristics of the bed at the point where sampled and are used to indicate the general quality of the bed in the county. The principal results and conclusions are: 1. Raleigh County contains large reserves of high-quality, high-, medium-, and low-volatile coals. 2. The principal beds from which an increased amount of coal is expected to be mined in the future are: The Eagle, Powellton, No. 5 Block, Hernshaw, Fire Creek, and Pocahontas No.6.

Jan 1, 1954

By Claus G. Goetzel

SOME of the reactions and procedures upon which modern techniques in the production of metal powders are based were used for 2000 years by the ancients to reduce iron and other metals from their ores. Despite this, however, the art of powder metallurgy is relatively new and probably stems from the introduction of incandescent electric lamp filaments. Attempts to improve upon Edison's carbon filaments led to the production, in order. of metallic filaments of osmium. tantalum.. and finally of tungsten, which ha, replaced the others and is the commercial product of today. These metallic filaments were originally manufactured by the extrusion and sintering of a mixture of the metal or its oxide with a reducing agent which also served as a binder. Further progress in this direction was in the pressing of a small percentage of nickel with the tungsten. The sintering operation was carried out in an atmosphere of hydrogen, at a tem-

Jan 1, 1944

Physical model testing at Bergbauforschung is done in two rigs, a roadway rig and a longwall rig. The loading of such models, in scale relation to the con- ditions in the collieries provides valuable guidance to the probability and nature of failures, and thus to support requirements, in structural, roofbolts and self- auvancing supports. The success of such modelling when related to subsequent underground designs put to use suggests that such methods of investigation could be extended to pillar extraction problems also.

Jan 1, 1974

By A. S. Ibrado

The adsorption of silver on activated carbon from cyanide solutions was studied as a function of concentration, ionic strength and pH. In cyanide solutions, silver exists mainly as the linear Ag(CN)2 complex and adsorbs on activated carbon following the Freundlich isotherm. The uptake and rate of adsorption increase with the addition of KC1 and KNO3 but changes only slightly with pH. In contrast, the adsorption of Cu(I), Zn(II), Cd(II), and Hg(II) shows marked changes with pH, closely following the predominance profiles of their neutral and singly-charged cyano complexes. Clearly, multicharged negative complexes are repelled by the negatively-charged carbon surface. This sensitivity of activated carbon to the charge of the adsorbing species indicates that silver adsorbs as an anion, not chemically bound to the co-adsorbing counterions. For the same reason, activated carbon is selective to metals that form neutral and Singly-charged cyano complexes, namely gold and silver.

Jan 1, 1988

By Tuomas van der Meer, Jukka Tanninen, Annukka E. Mäkinen, Mika Martikainen, Laura M. Nevatalo

The mining industry consumes huge water volumes and the waste streams typically contain sulfate, which has caused problems to many operations around the world. Discharge of sulfate to fresh waters is being restricted as the sulfate load increases salinity and causes problems when sulfate is reduced to toxic H2S by natural bacteria. To reduce fresh water consumption, internal water recycling had become a necessity in metallurgical processes. However, the recycling causes accumulation of sulfate and other components in water, causing problems to process performance and increases scaling in piping and equipment. Few technically feasible water treatment processes exist in the market that can be applied to decrease sulfate concentration below gypsum saturation level: biological sulfate reduction, membrane separation, ion exchange, evaporation and chemical precipitation. Some of these technologies are effective for treating wastewater, but there is typically a highly concentrated sulfate fraction left requiring still further treatment. Outotec has developed a sulfate removal solution, Outotec Ettringite process, which allows flexible control of residual sulfate concentration, thereby opening doors for increased water recycle within processes and control of the sulfate in discharged waters. In this article the results and benefits of this novel process along with examples of operating costs are presented.

Jan 1, 2014

By C. B. Espag de Klerk, J. de Goede, M. Le Roux, Q. P. Campbell

"Excessive amounts of moisture in product coal can influence the efficiency of downstream utilization processes due to a decreased calorific value and handling problems. Stockpiles can be used to decrease the moisture content of coal by means of gravity drainage and evaporation. This paper is focused on the evaporation of moisture from a coal stockpile surface with the aim of investigating the effect of particle size on the rate of evaporation as well as the depth to which evaporation extends.It was observed that moisture initially evaporates at a higher rate from a stockpile consisting of fine particles (-6.7 mm) than from coarser particles (-13.2 mm +6.7 mm). This high rate of evaporation is restricted to the outer shell of the fine coal stockpile. However, for coarse coal, the porous nature increases the depth at which evaporation occurs. Evaporation of moisture was observed up to the fourth day of each experimental run, after which steady state was obtained. It was shown the water can evaporate from the surface into the body of the stockpile, depending on the coal particle size and void spacing. An experimental reclaim depth of 0.4 m was achieved after 4 days. IntroductionCoal stockpiles serve as surge capacity for downstream utilization processes and can also be used for moisture reduction by means of gravity drainage and evaporation. Excessive amounts of moisture in coal can cause handling problems and, most importantly, will decrease the calorific value, leading to inefficient combustion.Research has shown that evaporation by means of wind and solar action is considerably more effective than gravity drainage(Williams, D.J. 2006), but the effect is limited to a restricted depth from the exterior of the stockpile (Boyapati, E. and Oates, A. 1994; CSEM-UAE, 2010). The effectiveness of wind and solar action can be improved by orienting the stockpile perpendicular to the predominant wind direction, maximizing the surface area of the pile, and reclaiming the coal from the pile gradually in shallow cuts over a large area (Williams, D.J. 2006)."

Jan 1, 2016