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Iran possesses very large copper resources, estimated to contain around 4-5% of the world's known copper inventory. There are several small private sector copper mining operating in the country, but Iran's copper industry is dominated by the state-owned National Iranian Copper Industries Company, which operates the world-class Sar-Cheshmeh open-pit Mine. This mine was developed in 1970s before the 1979 Islamic Revelation by the Atlantic Richfield Company (ARCO), the former Anaconda Copper Mining Company. Current Iran?s copper cathode production is about 250,000 mtpa and recently it is targeted to reach to 700.000 t by 2014. The required finance for this target is estimated US $2.25 -b, i.e. US $5000 for each tonne capacity. The copper content of the mineable reserves of the country is estimated about 19 Mt. It is not unlikely this amount increases in close future. Currently, almost 30 projects consist of mine, concentrator, smelter, refinery, acid plant, leaching, bio-leaching are underway. These projects are a golden opportunity for the local and foreign companies, but the recent sanctions are very challenging that all studied in this paper.

Jan 1, 2012

By John G. Kuhm

INTRODUCTION The goal of any development drilling program is the drilling of the exact number of holes necessary to adequately determine grade and dimensions of an orebody, no more and no less. This cost of development drilling represents a large part of the total development budget. Any technique which eliminates unnecessary drilling costs produces beneficial results, both to the company and to the person who can claim the savings. This high development cost factor has produced a quantity of research to develop techniques, for efficient control of drilling programs. Recent mining literature is full of articles describing methods for measuring and increasing the effectiveness of these expensive projects. The method described in this paper was developed during the latter part of a major development drilling project at the Christmas Mine of Inspiration Consolidated Copper Company in Gila County, Arizona. It was used to test the need for drilling individual holes but could be expanded to control an entire project. This technique was used at Christmas as a practical means for evaluating adequacy of drilling on an individual hole basis, and it was possible to eliminate several previously approved holes. Application of this method involves an evaluation of geological conditions present and a good bit of common sense. Projects involving large disseminated, rather homogeneous orebodies of the porphyry-copper type would be the most likely candidate for application of the technique. Discontinuous orebodies would not be amenable to this technique. The method is based on the measurement of the linear correlation between the spatial distribution of two sets of data. The Pearson product-moment correlation coefficient is used. This is a standard statistic commonly used to measure linear correlation between two sets of data. The statistical significance of the correlation coefficient at a 95% confidence level is the main criterion for controlling the project. For purposes of reference we will call our technique the "correlation method" in this paper.

Jan 1, 1971

By Christopher J. Bise

Traditionally, mine drainage systems have not received the high level of emphasis on careful engineering design which has been rendered to many of the other auxillary operations. This may be due, in part, to the situation-response approach toward dealing with an influx of water. When the installed system becomes inadequate, costly alterations to the pump, such as staging or speed increases, are considered expedient solutions. In order to rectify this situation, computer-aided solutions to mine drainage problems could represent an efficient alternative to the methods presently used. This paper will consider the application of microcomputer technology to mine drainage problems and will show how the relative economy and convenience of microcomputers can make them become valuable analytic tools at any mine site.

Jan 1, 1983

By R. R. Klimpel

The use of froth flotation as a means of separating and upgrading sulfide mineral concentrates is standard industrial practice throughout the world. Froth flotation is also widely recognized to be a very complex system having highly interactive and often self-compensating factors at work. Several summary articles have been recently published which discuss at length some of the important practical aspects of optimizing the use of existing commercial flotation reagents. Klimpel (1987). Klimpel and Hansen (1987a), Klimpel and Hansen (1987b), and Klimpel (1988). It is apparent from monitoring the industrial practice of sulfide mineral flotation over the last decade that considerable progress has been made in optimizing the operating aspects of flotation. For example, the availability of improved instrumentation and related computer devices, modified mechanical flotation cell designs, better reagent dosage control leading to less reagent usage per ton of ore, blending of feed ores, more attention to coarse and fine particle flotations, etc., are all examples of this progress.

Jan 1, 1988

The last decade has seen the use of powerful computerized Mine-Wide Monitoring (MWM) systems for detecting hazardous conditions in underground coal mines. Recently, the U.S. Bureau of Mines and Jim Walter Resources, Inc. (JWR) expanded the scope of MWM system to include ground control. Single-point extensometers were installed in each of 30 intersections along a tailgate entry. These instruments monitored the rate of roof sag, a sensitive indicator of roof instability. Data were collected by the mine's own computerized MWM system. The paper describes the successful integration of ground control instruments into MWM, the data reduction procedures, and the identification of several hazardous areas.

Jan 1, 1994

By Randy Ynchausti

ERIC GUTIERREZ, Knowledgescape: Our next speaker is Randy Ynchausti. He's the director of development, Knowledgescape systems division, of EIMCO Process Equip- ment Company. The title of Randy's talk is "An Expert Control System for Phosphate Beneficiation." RANDY YNCHAUSTI: System integration. How does the systems integrator survive when caught between plant engineers, plant management, and third-party engineering firms, and stay within the budget of the corporate goals? I'm not sure that anyone knows how to do all of that on one project. Results are critical when we talk about how systems integrators work with operating people, how the operating people want systems integrators to work with them, and how both groups work together so that at the end of a project, you have been provided with solutions that meet your needs and solve your problems at a fair price. How does the integrator's role change when working with different types of professionals, such as plant managers, plant engineers, engineering firms, or other system integrators? Finally, what is the dynamics of people working with machines and providing services and solving needs? The average number of employees per pound of copper processed has decreased significantly during the past 15 years. I would dare to generalize and say that the average number of employees per whatever unit of measure we have in whatever industry we work in has decreased over the last 15 years. From a system integrator's perspective, there are some clients who lack a bit of internal expertise as corporate downsizing occurs, and that's one reason why we go out to system integrators or third-party vendors and buy things from them to solve our problems. Downsizing really amounts to savings, but more than that, I think Brian expressed this and I agree with him, it also amounts to a cost. Unfortunately, most of us count the savings and none of us count the cost in that approach. It's easy to count the savings, which is one reason why we count it so quickly. Maybe that also accounts for why we set our pencils down so quickly after we get that dollar value. Maybe we should pick that pencil up every once in awhile and refigure the expense, the cost to us, and determine what we're going to pay during the next year or two or three in losing that expense, or that staff. A broad experience base accumulated over projects at various plants helps system integrators to provide services to clients. This experience enables the system integrator to

Jan 1, 1998

By R. D. Hansen

This paper discusses the influence of frother type and dosage on recovery/selectivity in coal/sulfide mineral flotation as a function of particle size. It is shown that different frother structures do exhibit quite different but consistent performance characteristics depending on the underlying particle size ranges involved as well as the dosage levels of both the frother and collector. The data presented on existing commercial frothers end some new special purpose experimental frothers is used to illustrate some general operator guidelines on proper frother selection and use.

Jan 1, 1985

By D. Mohapatra

Extraction of Al(III) from aqueous sulfuric acid solutions into organic Cyanex 272®-carbon tetrachloride systems was investigated from a multi-component mixture containing aluminum, cobalt and nickel. Al(III) extraction efficiency was quantitative with 1.0 M Cyanex 272® in two stages at an aqueous: organic (A:O) phase ratio of 1:1 and an equilibrium pH of 3.2. The stripping of Al(III) from the loaded organic (LO) with different acids indicated sulfuric acid to be the best stripping agent. More than 99% stripping of Al(III) from the LO was achieved using 2 M H2SO4 at an A:O phase ratio of 1:1 in a single stage. The stoichiometry of the extracted species of Al(III) was determined by the slope analysis method. The extraction reaction proceeded via the cation exchange mechanism and the extracted species was assumed to be AlA3?3HA, where HA refers to the dimeric and A the anionic form of the extractant, Cyanex 272®. The extraction of Al(III) was studied in the presence of various ions to ascertain the tolerance limit of individual ions.

Jan 1, 2008

By S. R. Clark

"INTRODUCTION Of all the natural resources being taxed by the needs of the modern world, perhaps the most important is the continually expanding demand for water resources. As water becomes scarcer, and increasingly important, new technologies are needed to find innovative ways to preserve this precious resource. In Chile, for example, the mining industry is investing billions of dollars to build desalination plants and pipelines; bringing ocean water as far as 200 kilometers inland to meet their demand and maintain operations. It is a full-blown crisis for that nation and a top priority for their government and economy. It has been reported that world water consumption will increase by 40 percent in the next 10 years, representing nearly exponential growth. In the U.S., as more and more communities continue to be built, more drain on the current water infrastructure is created. For 25 percent of people and operations that rely on water from aquifers, this source is being consumed at a rate that will create significant problems meeting the demand in as few as two generations.1 A PROACTIVE APPROACH When it comes to controlling dust at your operation, whether a landfill, a transfer station, a haul road or another ancillary area, what are the options? We know watering is not the answer, but at the same time, we need to prevent dust from flying to ensure a safe environment and keep our skies clear of pollution, for both regulatory requirements and neighbors. Creating a Dust Mitigation Program instead of looking to buy the first dust control product off the shelf is a first step to conserve water and, at the same time, maintain the operational demands and environmental standards for a given site. The program concept is straightforward enough. However, the process of effectively constructing and executing a program is quite involved. When undertaking a program, each manager needs to work with their team and their partners/vendors in analyzing the following elements: 1. Site Expectations—It is important to understand how to balance your internal standards with your regulatory requirements, as well as how to keep your neighbors satisfied. 2. Site Aggregate—Variations in native soil, such as clay content or gravel levels, greatly affect the approach that will yield the highest results. 3. Climate—Relative humidity and seasonal variations are critical to achieving predictable results through product choice, application frequency and timing. 4. Daily Traffic—The type and frequency of traffic is an essential variable for site management. 5. Environmental Responsibilities—If you have additional, specifically defined responsibilities, the approach to your site may vary. 6. Budget—While efficiency is the goal of any program, some sites will have more stringent restrictions than others. 7. Current Usage Rates—Document and understand where you’re starting from, both with water, supporting products, and maintenance so that effective measurement of results is possible."

Jan 1, 2018

By C. Bateman, F. Calizaya

"This study presents the results of three laboratory experiments on pressure balancing carried out at the University of Utah’s coal mine ventilation model. The model includes simulations of two working areas, one longwall mine gob, and a set of stoppings and seals. It also includes a pressure chamber between the longwall face and the gob. The model is ventilated by one main fan and one bleeder fan. A carbon dioxide injection system, equipped with flow control valves operated by a microprocessor, is used to pressurize the chamber and to maintain the pressure in the chamber slightly higher than that of the gob. During each experiment, fan pressures and stopping resistances were changed, the carbon dioxide injection rate was regulated, and the differential pressures across the stoppings were monitored so that the chamber pressure is always kept slightly higher than that the gob pressure. Result of these experiments are reported in this paper. INTRODUCTION Spontaneous combustion (Sponcom) is a safety hazard in underground coal mines. The history of coal mining in the US is replete with mine fires and explosions. Sponcpm accounts for approximately 17% of the total number of fires recorded in the U.S. since 1990. In the U.S., by law, worked out areas in coal mines must be either ventilated by a bleeder system or isolated by explosion proof seals. Experience has shown that seals are not airtight structures and that they allow some leakage of air into or out of the gob. In fact, seals “breathe in and breathe out” with changes in barometric pressure (Francart 1997, and Chalmers 2010). These changes in pressure affect not only the methane emission rate but also the ingress of oxygen to the gob, the lower the pressure behind seals is, the higher the ingress of oxygen. In mines ventilated by a U-tube exhaust system, the gob is often kept under negative pressure. Under these circumstances, an increase in barometric pressure may cause an influx of fresh air into the gob. This quantity may be sufficient to start self-heating of the coal, which can lead to spontaneous combustion. Depending on the coal characteristics and the ventilation conditions, self-heating of coal can start at temperatures as low as 35 ºC. If the heat is not removed it will increase the coal temperature leading to ignition and fire. The risk of Sponcom fires can be reduced by isolating the mine gob using rated seals, and implementing a suitable ventilation system. However, isolation seals are not airtight structures, thus some leakage of air is expected unless the pressure in the gob is neutralized. The alternative is to use a pressure balancing system. This requires a thorough knowledge of the ventilation system, the seal/stopping construction techniques, the airflow behavior in the gob area, and the gas build-up behind the seal line."

Jan 1, 2016

By O. M. Johnson

Barite and bentonite are the two principal components of drilling fluid systems used in the petroleum industry for oil and gas well drilling with rotary-type rigs. Approximately 87 percent of the world's annual production of barite is used in drilling applications. Of the worldwide production of bentonite, an estimated 30 percent is used. The drilling fluid, or drilling mud, to which barite and bentonite are added, performs five distinct functions: Lubrication-The liquid phase of the drilling mud lubricates the drill bit, preventing premature failure of the cutting edges and bearings. it also helps to soften the formation being drilled. Cuttings Removal-A mud system must be able to carry rock cuttings broken loose by the bit up to the surface where they can be removed by mechanical or chemical methods. The fluid's ability to perform this function depends upon maintaining a proper balance between the rate of circulation of the fluid and the colloidal properties required to entrain the cuttings in the mud to prevent their settling to the bottom of the hole. Hole Stability-The pressure exerted by the mud against the wall of the bore hole prevents the collapse of the uncased portions of the hole. Downhole Information-The fluid characteristics of the mud should be such that good cuttings samples, cores and electric logs may be obtained to help evaluate a well's productive zones and potential. Control Oil, Gas and Water Flows-It is essential that a drilling fluid offset any pressure from naturally occurring formation fluids in order to prevent a potentially wasteful and dangerous blowout.

Jan 1, 1980

By G. E. Wasson

Coal in most refuse ponds including those owned by Consolidation Coal Company can be recovered by froth flotation techniques. Laboratory studies show that the flotation conditions required for coal recovery varied greatly from pond to pond. The variables found to be most important for high coal recovery and low product ash were: a) the amount and type of flotation reagents and b) the degree of conditioning before flotation. Coal recovery at a rate of 0.504 kg/s (2 tons/hr) was demonstrated at a pond site employing a mobile froth flotation unit.

Jan 1, 1988

By Eckart Schneider

PROJECT The Walgautunnel is the heart of a new hydro scheme in Western Austria, which is supposed to go into operation in 1984. With it's length of 21,4 km, a bored diameter of 6,25 m and an internal operating pressure of 13,5 bar it will be the largest water conducting tunnel in Austria. Even compared with some of the country's world-famous highway tunnels like 'Tauern' or 'Arlberg' it has to be regarded as a major tunneling project. Owner is the Vorarlberger Illwerke AG, a power corpo¬ration founded in 1924. In the course of the past 6o years this company developed the 'Werksgruppe Obere Ill - Lünersee', consisting of 6 major power plants and 4 large reservoirs. The installed capacity is 1.114 MW in the generating and 529 MW in the pumping mode. The total power output amounts to 1.916 GWh. The water for power generation comes from the glaciers of the Silvrettagroup, as this corner of the Austrian Alps between Vorarlberg , Tyrol and Switzerland is called. The Walgauwerk utilises all the water accumulated by the existing schemes as well as the so far unused run-off water, passing by in the river Ill. The intake to the Walgau-Tunnel is situated right beside the lower reservoir of the recently completed pump-storage plant 'Rodund II' at an elevation of 64o m above sea level. Though the head is a mere 162 m, 1 billion m3 of water will generate 356 GWh per annum. The power-output of the two Francis turbines is 86 MW.

Jan 1, 1983

By Rolf Hindstroom

Outokumpu Mintec started development of the pressure filter in 1991, and the first unit was delivered to Tara Mines Ltd. Ireland in 1992. The filter replaced a conventional disc filter and a thermal dryer. The replacement of the thermal dryer has improved both environmental and working conditions. The filter is currently dewatering 80,000 tons per year of lead concentrate, producing a cake with less than 6 wt % residual moisture.

Jan 1, 1995

By D. Hodouin

The improvement of mineral processing data using material balance computer programs is nowadays a current practice in many plants, engineering companies or research centers. It now becomes more obvious that such programs should integrate new features such as the preprocessing of data, the estimation of less accessible process variables and an in-depth interpretation of: the computed results. A few solutions to these new problems are already available. The feasibility of a mass balance computation for instance can be examined by analyzing the degree of redundancy of the measurements prior to any data adjustment. New variables such as chemical analyses in particle size intervals or liquid phase composition can be included in a set of measurements. Finally, a sensitivity analysis can be used to analyze the reliability of the results, to detect eventual outliers or to redesign a sampling scheme. Some illustrations of these new developments are presented.

Jan 1, 1989

By Dieter Loh, Mathias Knoll, Florian Werres

When a new tunnelling project starts, it has been a vital tradition for decades to cast and erect master rings horizontally on a flat surface to demonstrate the compliance with dimensional tolerances. Some tenders ask for the erection of two or even three rings upon each other or repeated master ring erections at intervals throughout the project. Especially for large diameters, this is a challenging and risky task for the workforce in the segment factory. A truck-mounted crane is often necessary, and in some cases it can take up to a week to complete a master ring. The concept of virtual rings has the potential to replace this tradition by assembling master rings digitally instead of physically. This is based on a best-fit approach, considering the 3D coordinates from laser tracker measurements of segments or segment moulds. Building a virtual ring, a sub-millimeter accuracy can be achieved, the alignment of neighboring circumferential and ring joints observed, and the fit of bolt holes checked. The traditional method, on the other hand, is discussed controversially despite the significant amount of work and risks—particularly as the horizontal position of the ring and absence of gaskets do not simulate the reality in the excavated tunnel. This paper will highlight the technical aspects of virtual rings, as well as their pros and cons, illustrated by a case study from London Thames Tideway where a total of 30 physical master rings could be replaced by virtual rings.

Jun 13, 2023

By C. C. Jobes, J. J. Sammarco, D. L. Anderson

Computer-aided control of a mining machine places its operator in a safe, remote location, thus reducing health and safety risks. Sensing systems that provide machine position (xy coordinates) and heading (yaw) are extremely useful in aiding remote positioning of mining machines. The US Bureau of Mines (Bureau) developed two sensing systems for position and heading information: a scanning laser system based on the Lasernet sensor and a mechanical position and heading system based on linear-position transducers. The Bureau is also investigating a system from Honeywell, the modular azimuth and positioning system (MAPS), that employs ring-laser gyroscopes (RLGs). This paper presents a brief background and status of these sensing systems as applied to a continuous mining machine (CM). Included are field test results off each system operating in a room-and-pillar research section at a cooperating West Virginia mine.

Jan 1, 1993

By Y. K. Yen

The most serious problem for on-line coarse particle size measurement from a conveyor belt by image analysis is the overlap phenomenon that occurs between adjacent particles. A methodology is developed and described in this paper to estimate the sieve size distribution from the overlapped projected particle images as might be obtained from a conveyor belt. Two aspects of the overlap problem have been taken into consideration. First, several image processing algorithms were studied to find the most suitable technique to separate the projected overlapped particle images for narrow sized particles. These image segmentation algorithms include two-dimensional thresholding, edge detection and Watershed discrimination techniques. The other aspect of the overlap problem is related to the determination of the general kernel function for the partial particle images obtained from the projection of the overlapped particle bed. In this regard, a computer simulation technique was applied to mimic the overlapped particle bed for narrow sized particles, then the general kernel functions of the partial particle images were determined.

Jan 1, 1994

By James M. Neilson

In contrast to the rather generalized title of this paper, the subject of discussion will deal with two specific cases of sliding in glacial lake clays in northern Michigan. The slides in question occurred on lands owned by the Upper Peninsula Power Company a short distance south of Lake Superior. Slope failure problems have plagued the Company's operations for many years. It is hoped that this paper may provide some insight into the causes and possible mechanisms of clay slides in general as well as providing details of the two slides specifically cited. LOCATION The Upper Peninsula Power Company's Victoria facilities lie in section 29, T. 50 N., R. 39 W., in Ontonagon County, Michigan. The power site is situated on the West Branch of the Ontonagon River, approximately five miles southwest of the town of Rockland and only one mile to the southeast of the old mining location of Victoria. The area lies wholly within the Precambrian Shield and it is geologically similar to adjacent parts of Wisconsin, Minn¬esota, and Ontario. (Figure 1). THE VICTORIA HYDROELECTRIC SITE The Victoria hydroelectric power facilities were constructed in 1930 on a portion of the West Branch where meanders are conspicuously developed. The generating station is actually sited on an abandoned meander at a place where valley widening has occurred. Water is conducted from Victoria Dam through a 6000-foot, 10-foot diameter wood stove pipe - through a surge tank - and into the powerhouse where

Jan 1, 1971

By Magnus Ericsson

The unexpectedly quick recovery in world crude steel production in the second half of 2009 was due almost entirely to increased production in China that began in late 2008. Previous peaks in monthly production in China were matched by April 2009. The rest of the world had still not reached pre-crisis production rates by May 2010. Chinese production drives growth, but there has been some growth in most other larger crude steel producing countries as well, compared to production in 2009. If the production rate of the first four months of 2010 continues, the total output of crude steel in 2010 will be somewhere around 1,410 Mt (1.5 billion st), the same as in the record year of 2007.

Jan 1, 2010