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By C. Van Den Heuvel, C. B. Van Buuren

BIOX® has been successfully demonstrated over the past 2 decades for the recovery of gold from refractory sulphide concentrates. To date 12 successful BIOX® plants have been installed in 8 countries spanning 4 continents with the 13th installation currently nearing completion in the Philippines. In 2010 BIOMIN introduced the ASTER™ process for improved water balances in commercial BIOX® applications by supporting tightening environmental legislation on water usage and availability in both arid and tropical regions. Previously, a common challenge for BIOX® plants was the inability to recycle thiocyanate containing water due to the low tolerance of the organisms. ASTER™, a biological thiocyanate and cyanide destruction process, renders a non-toxic solution for re-use in BIOX®. Two commercial ASTER™ plants are in operation with the 3rd ASTER™ plant under construction in the Philippines. A 3rd BIOMIN technology, specifically developed for double refractory ores is available for implementation. The HiTeCC process has shown considerable success on ores where competition from disseminated carbon has rendered ineffective gold recoveries. Through HiTeCC, gold is desorbed from the carbonaceous matter by manipulating the ionic strength and temperature of conventionally treated CIL product. One Australian commercial plant utilises HiTeCC while a 2nd installation is set for commissioning 4th Quarter 2014. BIOMIN’s premier solutions for refractory gold processing are described herein.

Jan 1, 2014

By C. Moreland

Fluidized low-temperature carbonization of coal, a recent development, offers a possibility of reducing fuel costs of coal-burning electric ?generating plants. The Research Council of Alberta have built a pilot plant and are conducting a programme to -develop a carbomzation plant for Alberta sub-bituminous coals which will produce char suitable for use as a .boiler fuel, and tar of a potentially high value as a ?chemical raw material. The economies of the process as a whole, and the value of the tar, have yet to be assessed.

Jan 1, 1958

By M Russ, J Gediga

This paper shows an economic feasible approach to implement greenhouse gas (GHG) reduction measures into the mining and metallurgy industry (MMI). The goal to improve energy consumption is directly linked to the reduction of GHG emissions in the MMI. A baseline scenario of the considered reference system and of the respective reference year has to be designed and analysed. In a second step an analysis of the same operation using the best available technology (BAT) processes is carried out to generate a basis for a benchmark system. The identified gaps will be reported and the potential GHG emission reductions will be put into relation to the investment, running cost and generated carbon credits of the new process technologies to be implemented. This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap decision-making for implementing new technology into the companyÆs business operations. The GHG reduction roadmap is developed using the marginal abatement curve approach.

Jan 1, 2009

By Jafar Safarian, Leiv Kolbeinsen, Stian Seim, Hossein Salehi

The present work aims to investigate the link between the oxidation and reduction of a weathered ilmenite concentrate in terms of phase transitions, microstructural changes, and element distribution. An ilmenite concentrate sample was pelletized and fired at 1000 °C in air, and as a result, the pellets were oxidized. The oxidized pellets were reduced by hydrogen gas at 1000 °C, which yielded almost complete metallization of the iron content of the pellets. The ore and the pellets were characterized in each step by XRD and SEM techniques, and distribution of elements and phases were investigated. Ilmenite, pseudorutile, and rutile were the main phases detected in the ilmenite concentrate sample, and depending on the weathering degree of the particles, different fractions of the phases were identified in their microstructure. It was found that irregular rutile grains dispersed in a pseudobrookite matrix is the morphology of the oxidized ilmenite phase. However, increasing microcracks and porosities were the only microstructural changes in the pseudorutile phase after oxidation in air. Studying the specific types of the ore particles and their oxidized and reduced forms indicated that the phase distribution in the ilmenite ore particles dictates the phase distribution in the oxidized and reduced ones. Results show that the morphology of the reduced particles includes a titanium (III) oxide matrix in which reduced iron globules are dispersed.

Feb 8, 2021

United Engineering Trustees, Inc. GEORGE D. BARRON ARTHUR S. DWIGHT R. M. ROOSEVELT The Engineering Foundation H. C. BELLINGER E. DEGOLYER J. V. N. DORR

Jan 1, 1932

By J. E. Spurr

"Zinc Industry in BelgiumBy March F. Chase, Consulting Metallurgist, Bureau of MinesBelgium for many years was the principal spelter producing country of the world. Gradually its production was surpassed by that of Germany, and Germany in turn lost first place by the production in the 77ti.tad States. For the ten years previous to 1914, 21.6 per cent of the world's spelter was produced in Belgium. Of this production approximately 40 per cent was exported. A large percentage of the balance was rolled and of the shoots thus produced a considerable quantity was also exported.From an economic standpoint even before the war, the Belgian industry was in a unique, if not praoarious, position. Dependent upon foreign countries for ore and foreign markets for sale of products, smeltor was at a distinct disadvantage when compared with some of those of other localities. These disadvantages were partly offset by cheap coal and labor and by whatever there is of value in experience and what we may term for want of a better expression smelting tradition. However intangible this latter may be, it did have and has today an influence on commercial operations.One must not overlook the effect it will have on the revival of the industry. It may not be the determining factor but the fact that for so many years this industry flourished in Belgium, and played such an important role in the industrial life of the country will decide many operators to attempt to re-establish their operations.In 1913 the Belgian spelter plants produced 204,220 long tons of spelter or approximately 20 per cent of the world's production. During this year 500,000 to of ore were treated. The actual value of all of the products derived from treating sine ore amounted to 225 million frames."

May 1, 1919

By Manoj Khandelwal, Bright Akuinor Tsidi, Newton Amegbey, Daniel Mireku‑Gyimah

One of the ambient effects of production blasting is flyrock. To effectively manage flyrock throw distance in mining, there is the necessity to successfully envisage blasting output without sacrificing the hazardous impact of flyrock which may result in fatality and operational shutdown. For flyrock throw distance prediction, velocity of detonation (VOD) and charge per bank cubic meter (CPBCM) are not usually included. This paper focuses on the use of support vector machine (SVM) regression to ascertain the impact of VOD and CPBCM on flyrock throw predictions. The machine learning models were linear support vector machine (LSVM), quadratic Gaussian support vector machine (QGSVM), fine Gaussian support vector machine (FGSVM), medium Gaussian support vector machine (MGSVM), and cubic Gaussian support vector machine (CGSVM). The outcome indicates that FGSVM was the most sensitive with a 4% improvement when VOD and CPBCM were included. As a result, the LSVM model provides a suitable AI competitive alternative tool for flyrock throw prediction in mining operations by incorporating VOD and CPBCM.

Feb 10, 2024

By Wallace W. Key

This report concerns types, quantities, specifications, and uses of non-metallic minerals as a basis for improving their supply, conservation, and utilization. Supply-demand details concerning mineral fillers, rooting granules, and roofing rock used in asphalt are incorporated in this report, along with highlights on production and sales of rooting, floor tile, and other related asphalt products of California. Comparable data for the United States are included. Although large quantities of commercially prepared mineral fillers are used in asphalt for paving and related applications in other States, addition of commercial fillers for these uses rarely is required in California because of the natural tines available. On the other hand, California manufacturers of asphalt products other than having utilize about 300,000 tons of asbestos, diatomite, limestone, mica, soapstone, and other nonmetallic minerals as filler, mainly for reeling and flooring. Also about 500,000 tons of roofing, granules is produced in California, most of which goes into roofing manufacture in California. In addition. A significantly large and growing tonnage of relatively coarse mineral aggregates Ire used on low-angle, built-up, asphalt roofs to produce in attractive surface and offer protection against the clements. Clearly ill minerals used in asphalt products manufactured in California come from local sources, except asbestos and mica--and there are indications that local deposits of those commodities could be utilized in some use categories.

Jan 1, 1966

By H. S. Sichel

"The valuation of diamond ferous deposits depends on (i) the density distribution, (ii) the size distribution of stones and (iii) the selling price structure prevailing at a particular time.In the density distribution the stochastic variable is defined as the Dumber of individual stones found per sample unit irrespective of the stone size. The density distribution is discrete and allows for barren sample units.As diamonds often occur in clusters, a Poisson mixture distribution is derived which is entirely new, as existing discrete distributions cannot represent the stone number frequencies found in nature.For the sizes of diamonds, which are measured by weight, a new compound logarithmic normal distribution is developed.Combination of (i), (H) and (iii) leads to a meaningful appraisal of diamond ferous ground expressed in monetary value per production unit of mining.Finally, confidence limits are calculated which allow for inference from sampling to recovery."

Jan 1, 2014

By W. H. Oppelt

Converting small-particle lignite to a stable, storable fuel of relatively high heating value was investigated. The fuel was prepared by thermal pretreatment of the lignite in an 8-inch i. d. rotary-drum retort, then the pretreated material was pelletized in an experimental 15-inch-i. d. rotary-drum pelletizer. Pelletizing tests were made with both starch and bituminous binders. During the first phase of the project, the quantity, composition, and heating value of products from the thermal processing of Kincaid lignite from Burke County, N. Dak., in an B-inch i. d. rotary-drum retort were investigated at a series of temperatures from 250° to 950° F. to establish optimum conditions for preparing feed material for pelletizing. To determine the response to thermal treatment of different lignites, 5 other lignites from Divide, McLean, Mercer, and Stark Counties, N. Dak., and 1 lignite from Saskatchewan, Canada, were processed at 700° F.

Jan 1, 1958

By S. Razi

Injection luminescence of single crystals of rare-earth-activated CdS was investigated. Crystals of CdS:Nd, CdS:Er, and CdS:Yb, grown by the vapor transport technique, were suitably etched and hetero-junctions of Cu2S-CdS were fabricated on one side of the CdS substrate by chemical reaction. The device was then heated to 200°C in an inert atmosphere for 5 min. Static V-I measurements show that at low voltages (V < 1 v) the current is controlled by the junction, while at higher voltages the bulk Properties of the CdS substrate effectively control the current. Because of the large thicknesses no negative resistance was found. Reverse breakdown voltage varied from 5 v, for junctions that were not heat-treated, to 100 v, for diodes that received the proper heat treatment. The rectification ratio, measured in the range of 2 to 10 v, varied from 300 to 3000. Capacitance- voltage measurements indicate a weak dependence of the junction capacity on applied voltage. The capacity was found to increase appreciably with room light illumination. The variation of capacitance with frequency is indicative of a p+-i-n structure. An open-circuit voltage of 0.4 v was measured under an illumination of 100 mw per sq cm. Under forward bias, the bluish-green edge emission characteristic of CdS was observed. No sharp rare earth emission line was observed, which is in contrast to our results using ZnS:Tb, where, under high-voltage excitation, the rare earth emission was dominat over the lattice emission. The absence of rare earth emission implies that either the nature of the rare earth ion is different at the het-erojunction than in the bulk or the probability of energy transfer to the rare earth ion is small. RARE earth elements are playing an increasingly important role in the Synthesis of materials for a variety of purposes, e.g., solid-state lasers, color television screens, and so forth. Interesting systems result when wide-band-gap photoconducting lattices are activated with rare earths. A study of the lumines-

Jan 1, 1969

By Haydn H. Murray

Kaolin is defined and described as an industrial mineral. In addition the types of deposits -primary and secondary are defined and the genesis of kaolin from feldspars and other minerals discussed. The major deposits of the world found in the United States, Great Britain, Brazil, and Czechoslovakia are described along with many of the minor kaolin deposits. Four areas which have very large deposits of kaolin could, with technological breakthroughs to reduce viscosity significantly, become important factors in supplying the world markets which are increasing year by year.

Jan 1, 1977

By Knut H. Hubert

The GRATE-KILN System plant at Svappavaara, Sweden, was constructed for LKAB by Allis-Chalmers under a turnkey contract and commissioned in 1969. The plant was designed to produce iron ore pellets from magnetite concentrate at 6100 mtpd using imported fuel oil. It represented the state of the art for plants of its type at the time. Fuel rated capacity was attained within one week of start-up. Product quality, power usage, fuel consumption and machine wear were within warranty limits during sustained production thereafter. As operator skills improved and gas handling system reserve capability was utilized, the plant frequently produced acceptable product at up to 115% of design capacity. During the period 1969 to 1976, market demands increased for high-quality pellets while energy costs rose steadily. At the same time, important advances in the design of GRATE-KILN Systems were being made in other plants constructed by Allis-Chalmers.

Jan 1, 1980

By R. K. Guthrie, H. B. Hill

"INTRODUCTION The Rodessa oil field in Marion and Cass Counties, Tex., Miller County, Ark., and Caddo Parish, La., was discovered in August 1930, when a well drilled to a depth of 5,506 feet in Caddo Parish, close to the surface trace of the Rodessa fault, produced gas in commercial quantities. During the next 5 years 21 gas wells were drilled, and a large reserve of natural gas was developed in the high part of the Rodessa structure underlying the Massive Anhydrite member of the Glen Rose formation.In July 1935 oil was discovered on the flank of the structure when a well drilled to 6,048 feet also in Caddo Parish, was completed as an oil well. The discovery of oil in the Rodessa structure initiated art intensive development program of more than usual interest to geologists, engineers, and operators in the petroleum and natural-gas industry. The complex nature of the different reservoirs, the large volume of ""free"" gas under high pressures and temperatures in the upper part of the reservoirs, and the high gas:oil ratios of some of the wells during the early production of oil presented many problems the solution of which taxed the ingenuity of those responsible for the development and exploitation of the Rodessa field.Early waste of gas and resultant dissipation of reservoir energy led to State intervention, which brought about effective regulation of the quantity of gas blown to the air. Oil production from wells producing more than 2.000 cubic feet of gas per barrel of oil was restricted, and oil allowables generally were based equally upon acreage and upon reservoir pressures. Consequently, oil-production statistics of the field are closely associated with gas:oil ratios and reservoir pressures.The primary object of this report is to present factual and statistical data on well performance in the Rodessa field and to show established trends under certain operating methods and practices in high-pressure gaseous reservoirs, which have been carefully developed and outlined by modern technique and exploited under close engineering supervision.The large size of the Rodessa field, it’s fairly well defined gas caps, and a somewhat definite water table in a part- of the oil- and gas-producing region are of special interest and importance in a study of the fluid and energy relationships in reservoirs. Consequently, the results of much of the authors' work in collecting and compiling date are presented in the form of tables, maps and cross sections to show the relative thicknesses of the different oil-and gas-producing members and their permeability and porosity relationships, and, when possible, the variations in stratigraphy are exhibited in cross sections. Results of a detailed analysis of cores from a number of wells also are presented in tabular and graphic form."

Aug 1, 1943

By Edgar Bain

SUMMARY THE results of an enquiry into the structural nature of some 70 iron alloys containing both nickel and chromium over a considerable range of concentration &apos;are briefly described in this paper. This study is a part of a comprehensive program of investigation into alloys involving chromium in progress at the Union Carbide and Carbon Research Laboratories. All the compositions studied contained carbon in amount comparable to commercial alloys.

Jan 3, 1927

By Gene Baker

A new Safety Library Publication (SLP), SLP-27, which is titled “Security in Manufacturing, Transportation, Storage and Use of Commercial Explosives” was recently released by the Institute of Makers of Explosives (IME). SLP-27 makes recommendations for both general security and enhanced security at explosives sites when security risk levels, declared by the Department of Homeland Security (DHS) using its Advisory System, have temporarily increased.

Jan 1, 2006

By Josh B. Taggart

Some twenty to twenty-five years ago we saw the beginning of mechanization in our coal mines, It has now progressed to the point Chat as instruments of production the pick and shovel are things of the past, They had to give way to better and more efficient methods--so mechanization, followed by and combined with automation, has become common-place in our mines. Our coal could not keep its competitive position without this progress Without it our industry could not look to the future with any degress of confidence. Today we lock back and see cases of regained and salvaged markets. We see better coal products being produced at decreasing costs. We see better utilization of manpower and a stronger, more confident industry, Our hats arc off to those mining men, equipment manufacturers, labor leaders, and others who had the foresight to work toward these ends and the ability to bring them about.

Jan 1, 1962

By John B. Hastings

THE reconnaissance of the Goldfield mining-district, described in this paper, was made in May and June, 1905, and, though this time was too short for a complete report, the work accomplished may serve as a basis for more thorough future research. Dr. Berkey has examined the rocks collected by myself, and I am using his classifications. As a result of further field-work, and Dr. Berkey&apos;s examination of the rocks, this paper is an elaboration and correction of my views expressed in the Gold-field Sun, May 12, 1905. The sketch-map, Fig. 1, illustrates the geology of the Goldfield mining-district. Goldfield is an eruptive complex, consisting of alaskite (binary granite), hornblende-andesite, hornblende-dacite, rhyolite, pyroxene-andesite, pyroxene-dacite (sometimes containing, a small quantity of olivine), quartz-felsite, olivine-pyroxene-ande¬site, and basalt. Considering this list to be arranged in the order of eruption, the age-sequence of the rocks conforms to Richthofen&apos;s law, formulated in 1868. From his observations in Europe and America, propylite, andesite, trachyte, rhyolite and basalt, occurring together, succeed one another. In a general way, the medium and more acidic rocks precede the most asic-a result supposed by some to have arisen from their relative position beneath the surface, and due to a rude stratification by gravity in the original cooling magma during the older history of the earth, or to the same differentiation occurring during a quiescent (molten ?) period preceding eruption, being aided by the ease with which acidic rocks, mixed with water vapors, become fusible. In effect, the more basic and less re-

Mar 1, 1906

By R. S. Dean

As set forth in the decision of the Trail Smelter Arbitral Tribunal, dated April 16, 1938 This Tribunal is constituted under and its powers are derived from and limited by the convention between the United States of America and the Dominion of Canada signed at Ottawa, April 15, 1935, duly ratified by the two parties and ratification exchanged at Ottawa, August 3, 1935 (hereinafter termed "the Convention") . . . The duty imposed upon the Tribunal by the Convention was to "finally decide" the following questions: (1) Whether damage caused by the Trail Smelter in the State of Washington has occurred since the first day of January 1932, and, if so, what indemnity should be paid therefor? (2) In the event of the answer to the first part of the preceding Question being in the affirmative, whether the Trail Smelter should be required to refrain from causing damage in the State of Washington in the future and, if so, to what extent? (3) In the light of the answer to the preceding Question, what measures or regime, if any, should be adopted or maintained by the Trail Smelter? (4) What indemnity or compensation, if any, should be paid on account of any decision or decisions rendered by the Tribunal pursuant to the next two preceding Questions? In this decision reported to the Government of the United States of America and to the Government of the Dominion of Canada, the Tribunal answered the first question in its entirety and reserved decision on the other three questions in accordance with the following extract from their decision

Jan 1, 1944

By Joseph M. Kurtak

The Bureau of Mines conducted a four year (1985-1988) mineral assessment of the Juneau Mining District in southeast Alaska as part of its ongoing statewide mining district evaluation program. Following an extensive literature search, the Bureau investigated mines, prospects, and mineral occurrences in the area. This report describes the results of Bureau work in the Eagle River area of the Juneau gold belt; a component of the Juneau Mining District comprising 87,000 acres between the Mendenhall Glacier and Berners Bay. Gold and silver have been the only metals having significant production from the area and occur mainly in quartz stringer and fissure type veins hosted by phyllites, greenschists, greenstones, altered diorite dikes and quartz diorite gneiss. Gold also occurs in several small placer deposits. Approximately 21,100 oz of gold and nearly 9,000 oz of silver were produced over a 60 year period. Currently, the only mining activity consists of some exploration and minor placer gold production. Inferred and indicated lode gold resources having mineral development potential total approximately 796,000 tons with a weighted average grade of 0.22 oz/ton gold.

Jan 1, 2011