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Mining was the first economic activity carried out in Cuba, by the colonial conquerous, i.e. gold extraction from rivers and use of asphalt to calk their ships; however, due to different historic reasons only a limited development took place in this field during the colonial domination. During the republican period beginning early in this century, other interests lead to a larger scale exploitation of some known deposits. From the beginning of the century up to the triumph of the Revolution in 1959, not less than the following figures were extracted of some Cuban minerals: Refractory Chromium 3,300,000t Manganese 7,650,000 t Copper 9,000,000 t Iron 22,000,000 t Nickel 150,000 t (Ni oxide and sulphide These productions were practically directed to cover the demands of the U.S., industry and some-times these Cuban ores were almost the sole suppliers of the market.

Jan 1, 1978

By Lassi Klemettinen

For better understanding and maximal value utilization of the WEEE smelting process, the behavior and distribution of different trace elements must be known. In this study, the behavior of nickel as a trace element was studied in an equilibrium system with metallic copper—spinel saturated iron silicate slag (with 3 wt-% K2O)—iron aluminous spinel—gas. The experiments were conducted in alumina crucibles at 1300 °C, in oxygen pressure range of 10−10–10−5 atm. A time series of 15–60 min experiments was also conducted for investigating the formation rate of the primary spinel phase in the system. The results show that the distribution coefficient of nickel between metallic copper and liquid slag changes from approximately 70 to 0.4 along the increasing oxygen pressure range. In addition, a significant part of the nickel deports into the spinel phase. The spinel formation was investigated based on composition analysis results and visual observations from SEM-images.

By Mohamed Y. Bakr, Aly M. Abdel-Rehim

The present work is related with mechanical activation of processing of Egyptian wolframite by simultaneous ball-milling and pressure alkaline leaching, to improve the recovery of tungsten from wolframite. The results show a total recovery of tungsten from wolframite (97.8- 98.7%) by simultaneous ball–milling and alkaline leaching at temperature 175-200oC. It is concluded that processing of wolframite by simultaneous ball- milling and leaching is mechanically activated and accelerated as a result of the grinding action of steel balls that caused the immediate rupture by continuous removing the product layer of the reaction ( sodium tungstate and iron and manganese hydroxides ) from reacting particle surfaces. This leads to the exposing of fresh and activated wolframite particle surfaces to alkaline leach solution and consequently the acceleration of the reaction of wolframite leaching .The results of the kinetic study 0f alkaline processing of wolframite and its mechanical activation show that the system is under kinetic control.

Jan 1, 2015

By G. W. Toth

The coal mining cost models described in this paper represent a computerized estimating procedure for analyzing mining costs and requirements of proposed coal mining projects. Both surface and underground mining analyses can be conducted through the use of these models. These models were developed by the NUS Corporation for the Electric Power Research Institute (EPRI). The methodology design of the cost models follows a process engineering approach for determining mining requirements and costs similar to the logic typically employed in preliminary mine feasibility studies. All capital and operating costs associated with a new coal mining project are thereby estimated. The results of these analyses are then entered into a financial analysis framework which computes annual cash flow summaries, utilizing a profit and loss statement approach, to solve for either the coal value/ton (minimum required selling price) or the rate of return on equity for the project. The coal value/ton is also referred to as the economic cost of production (F .O . B. mine, including preparation).

Jan 1, 1980

By Wilfred Walker

Much is known of the geography of the Alpine orogeny because it has now ended and all geosynclines are in their terminal, cordilleran form. The principle of sea floor spreading, continental drift, and mantle cells has gained general acceptance, but the number and position of the cells, even during the Alpine orogeny, is controversial. The oceanographers have demonstrated the uprises and in this paper it is suggested that downflows are marked by island arcs in the oceans and geosynclines (now cordillera) in the continents, for a total of about a dozen cells. Major mineral deposits associated-with the Alpine downflows are porphyry copper, molybdenum, nickel, chrome, lead-zinc-silver, gold, mercury, tungsten, and tin. Amore precise environment is known for some of these metals, for example, nickel, chrome, and mercury in flysch (which flanks mantle downturns), Ten major orogenies have taken place from 3500 m.y. to the present, Their re¬construction and metallogenesis is the subject of a continuing study.

Jan 1, 1971

By F. R. Cattoir, R. E. Cumings

Columbium metal was electrorefined in a fused - salt electrolyte . Excellent results were obtained in lowering the impurity content in a 94 - percent columbium anode feed material to produce a 99.8- percent - pure metal . The reductions of the major impurities follow : Oxygen from 19,800 to 500 ppm , carbon from 9,700 to 25 ppm , iron from 9,200 to 630 ppm , nitrogen from 2,100 to 90 ppm , and silicon from 750 ppm to not detected . Columbium with a purity of 99.9 percent was produced from 99.5- and 99.8 - percent grades of columbium. The investigation was devoted to the evaluation of a fused - fluoride - salt electrolyte ( KF - NaF- K₂ CbF, ) for electrorefining columbium. The effects of the columbium concentration and the voltage upon the product's purity were investigated . The effect on the cathode current efficiency of ampere - hours of deposition and the formation of a dual valence state of the columbium was also investigated .

Jan 1, 1964

By Y. J. Wang

This paper deals with the application of linear programming to the solution of mine ventilation network problems which involve only the controlled splitting of air. An airway whose air quantity is to be controlled to a prescribed value is called a "fixed-quantity" airway. In a network where the fixed-quantity airways are increased in number and are distributed such that the air quantities for the remaining airways are uniquely determined by Kirchhoff's first law, the problem reduces to determining the head losses and locations for air regulators and fans. This is one of the network problems encountered most often in underground coal mines. By formulating Kirchhoff's second law as a set of linear constraints and the total air horsepower supplied by fans as a linear objective function which is to be minimized, the problem is analyzed through the technique of linear programming. Some important properties of the problem are discussed and examples are presented.

Jan 1, 1971

By M. Smit, N. C. J. Dempers, S. Lunkov, C. Saguru, J. Nel

A common method for the recovery of copper is by heap leaching, solvent extraction, and electrowinning. During solvent extraction, the solution is continuously recycled, and it is necessary to remove impurities that build up in the raffinate. For the process investigated in this study, the main impurities include Fe, Co, As, and Zn. Recovery of these impurities can provide economic benefits while adhering to legal and environmental constraints. Such impurities are often removed by precipitation utilizing a neutralizing agent, such as limestone or lime, but it is also possible to remove the impurities by sulfide precipitation. Sodium hydrosulfide (NaHS) is used to selectively precipitate copper, arsenic, and zinc from a solvent-extraction raffinate stream. The resulting sulfide precipitate is bagged and sent to a roaster for further treatment. The design of the sulfide precipitation was investigated to optimize the processing conditions (including temperature, pressure, and residence time), the materials of construction, and the toxicity and explosive nature of the hydrogen sulfide gas produced

Jan 1, 2023

By J. S. Edwards

The ISASMELT? process is recognized worldwide as a modem, flexible, environmentally-friendly and low capital cost smelting technology. Due to the inherent simplicity, and the advanced process control that has been developed, personnel become competent within weeks of being introduced to the ISASMELT? technology. This compares with the years required to become proficient with alternative technologies. Copper smelters in Australia, USA, India, China, Peru and Zambia have installed ISASMELT? technology under licence from Xstrata Technology. In the secondary copper business, plants in Belgium and Germany are processing copper and/or lead materials in ISASMELT? furnaces in a two stage process. In a single furnace smelting is followed by converting. Both plants have exceeded design capacities and are continuously improving their performance. The next evolutionary step for the technology is the implementation of the continuous copper converting process on a commercial scale. The present work describes the design status of the continuous converting process - ISACONVERT?.

Jan 1, 2007

By Tiago Seixas Bittencourt

Technological developments, associated with the constant worry about the environmental impacts arising from industrial activity, it has driven the development of technologies and practices for efficient fumes and particulates capture arising from the manufacturing processes of steel in steel plants in general. Currently, the electric steelshops in operation with Electric Arc Furnaces (EAF), seek parameterize/design dedusting systems able to retain most of the particulates generated during melting and refining of steel in FEA through configurations of equipment, technologies and parameters operation in order to equalize the antagonistic relationship between effective fumes capture and energy balance of the EAF. The present work gets as a fundamental premise to evaluate critically the possible different settings of the usual dust removal systems, as well as their respective classical parameterizations. The work main purpose is to establish a general rule evaluation technique for dedusting system considering the different modes of operation of an Electric Arc Furnace.

Jul 30, 2018

By B. K. Shibler, J. V. Batty, G. M. Potter, H. D. Snedden

"INTRODUCTION As a part of the investigations of strategic mineral deposits in the United States under the Strategic Minerals Act. Engineers of the Bureau of Mines examined and sampled numerous deposits pf fluoride ores in the Western States. Sample from those deposits that warranted further investigation were submitted to the Ore Dressing Section of the Salt Lake Station for metallurgical testing. This paper gives data summarizing the results obtained from laboratory studios of fluorite ores submitted from 12 deposits in Arizona, California, Idaho, Montana, Nevada and Wyomong. Only four of the Ores were found to be amenable to beneficiation for the production of acid-grade fluorspar concentrates with good recoveries. However, all of the samples were amenable to the production of concentrates meeting chemical specifications for metallurgical-grade spar.For the sake of clarity and convenience in presenting data, this report has been divided into six parts, each pertaining to metallurgical studies of fluorspar ores of a single State."

Nov 1, 1947

By Georg Unland, Thomas Wegner

"Different types of impact crushers use the physical effect of impact to crush rocks. The rocks can vary from soft to hard and from ductile to brittle but they should never be abrasive. Since the principles of impact crushing of larger rocks are hardly investigated these crushers are still sized rather by empirical than by scientific approaches.In order to investigate the principles of comminution by impact of large rocks a test rotor was developed and rocks of different dimensions were tested. The integrated measuring devices of the rotor enable the recording of impact forces and of absorbed impact energy with high resolution during the contact time.Since impact crushers stress the rock particles with a defined velocity the main crushing properties are gained as a function of the applied velocity and the particle size of the rock: likelihood of breakage, contact time, maximum crushing force, mass specific crushing work, surface related crushing ratio and crushed fragment shape distribution."

Jan 1, 2003

By R. K. Sinha, B. S. Choudhary, Desh Deepak, A. K. Mishra, Hemant Agrawal, Shankar Kumar

There are several methods (empirical, statistical, and machine learning tools) to calculate blast-induced ground vibration. Still, due to complications in the blasting procedure, under varying blasting loads and strata conditions, it is not easy to predict and simulate blast vibration precisely. Therefore, a study was conducted to simulate the field blast data in Ansys software using explicit dynamics. For this study, monitoring of ground vibration for 20 single hole blasts was carried out. The density of emulsion explosives was in the range of 0.9 to 1.15 g/cc. In the laboratory, rock properties were determined from the rock sample collected from the mine site before blasting. The in-hole velocity of detonation (VoD) and the density of the emulsion explosive were also determined. These parameters were used for numerical analysis to know the ground vibrations at specified points. The results of ground vibration predicted by the model are validated using field data.

By J. C. Agarwal

Most metals are produced from minerals containing one or more of the desired metals, some contaminating metals, silicate, oxides, carbonates, and sulfides. Therefore, in the production of metals, there is generally a gaseous effluent in pyrometallurgical processes and a liquid effluent in hydrometallurgical processes. There are also solid residues such as waste ore, tailings, dust, and slag, created by the metal recovery processes. There are two important distinctions between the effluents and the residues: I. Effluents ? gases and liquids ? affect the neighboring environment for miles from the point of emission, while residues affect only the soil on which they are stored or dumped. 2. The environmental and economic effects of effluents are known and felt essentially immediately. By contrast, the environmental effects of the residues may not be known for a long time. For these reasons, the economic impact and the potential corrective actions required are very different for effluents and residues.

Jan 1, 1992

By C. E. Jordan

The Tuscaloosa Metallurgy Research Center of the Bureau of Mines, U.S. Department of the Interior, is investigating the recovery of phosphate from beneficiation slime, as part of the Bureau's efforts to conserve mineral resources through increased use of wastes. Phosphate equivalent to about two-fifths of U.S. production is discarded annually in the wastes. Exploratory flotation tests on the plus 5-um fraction of a slime sample showed promise for a classification-flotation technique. Onsite classification tests at six phosphate washing plants were conducted with a two-stage hydro cyclone system designed to recover the plus 5-um material. The cyclone underflows contained 8.3 to 19.1 percent P2O5, and the recovery of the plus 5-um PZOS values ranged from 81 to 95 percent. The percent P2O5 recovery from the total slimes ranged from 38 to 47 percent. Batch-flotation studies are currently being conducted.

Jan 1, 1978

By Grant J. Goddard

"The Iron Ore Company of Canada (IOC) has been in operation for over 30 years. Today, and in the future, technology and its application will play an ever more critical role in the company’s business success.The Carol Mining and Concentrating (CMC) division of IOC is energetically applying technology today to enhance performance and results, and is aggressively exploring opportunities to apply technology to support improved business results in the future.A critical area of focus is the application of technology to maintenance management performance. CMC has taken a “back to basics” approach to the fundamentals of maintenance management in 1995 and 1996. In parallel, the mine is aggressively implementing its Vision 2000 maintenance integration plan. This plan is targeted at levering the energies applied to sound maintenance management fundamentals as the company moves to a fully condition based maintenance approach.This paper discusses some of the strategies, key technologies and objectives of theVision 2000 maintenance integration plan at the mining operations of IOC."

Jan 1, 1996

By J. W. Craig

CHROME ore, which is used in Canada in the production of ferro-alloys, in a variety of refractories, and indirectly in many chemical industries, is both commercially important and scientifically interesting. The sight of chromium metal is familiar to all of us in the home, the office, the automobile. Chromium is synonymous with armaments: it is understood to be one of several essential metals in tanks, which played an important role in the defeat of France in the spring of 1940. Chromium, in other forms, comes into our daily lives by way of paint and leather, of the familiar green ginger-ale and beer bottles, and more indirectly in every pound of steel produced in the .Dominion. Necessary to our civilization in peace and war, the ores of chromium occur in many corners of the earth. This paper attempts to describe the chemical constitution of chrome ores, their world distribution, and the various chrome products and their industrial applications in Canada.

Jan 1, 1940

By AIME AIME

THE Institute of Metals held a well rounded out symposium on the working of metals, distributed over two sessions. At the first session* four papers were presented, two dealing with the, cold working of metals and alloys and two with the hot working of non-ferrous alloys. The first paper by E. V. Crane, dealt with "Metal Working in Power Presses." Mr. Crane pointed out the empirical nature of engineering data available for use in calculating the probable stresses developed and power requirements, for the shearing, drawing, binding and other forming operations. He described the various operations, methods of determining stresses developed and presented data obtained. In the discussion C. F. Hammond took exception to Mr. Crane's objections to the rather too frequent. annealing operations in drawing of cartridge cases, pointing out that the material was-manufactured to meet specified structure and physical requirements, which could only be met by carefully controlled sequences of working and intermediate annealing operations.

Jan 1, 1931

By C R. Crook

A brief outline of production methods and processes is given to show how maintenance fits into the picture at this plant. The work force, and the tools needed to carry out this function, are then described. Preventive maintenance practices, scheduled annual shutdowns and routine check-downs are explained, especially as related to planning and to the materials and labour involved for a mini-mum downtime. A brief explanation of the materials, sup-plies and spare parts program, as well as the part played by the Stores Department in conjunction with the Maintenance Department, is given. Cost control and equipment expenditure indicators are explained. Some specific examples of maintenance jobs are described in order to show the flexibility of the program. S HERRITT GORDON Mines Limited has been in continuous production, except for the planned downtimes needed for expansion tie-ins, or the annual shutdown check-over periods, since the first shipment of nickel on a commercial basis in July of 1954.

Jan 1, 1964

By Ljiljana Solujic

The need for the removal of mercury from the precious metals extraction circuits may be influenced by process, environmental, as well as by occupational hazard reasons. In these circuits mercury is mainly present as cyanide complexes. The effectiveness of any stabilization method will be influenced by the high thermodynamic stability mercury-cyano species exhibit in an aqueous solution. In this study, we have investigated the utility of the trisodium salt of trimmercapto-s-triazine (TMT) for precipitation of mercury from the corresponding cyano-complexes. The influence of pH molar ratio of TMT to Hg, coagulant and flocculant additions, excess of free cyanide, as well as the presence of other metal-cyano species on the effectiveness of mercury precipitation were investigated in detail. Also, a "teal world" precious metals mill effluent initially containing ~7 ug/mL (ppm) of Hg was treated and A was found that greater than 99.8% of the mercury was removed from the solution as am insoluble Hg/TMT complex.

Jan 1, 1996