Search Documents

By D. Loy LeRoy

As we are all aware, the impacts of the 1977 Surface Mining Act and the implementing OSM Regulations require application of new, as well as existing, equipment and technologies. Our firm recently completed (June, 1979) a study for the Department of Energy titled "Analysis of the Impact of Public Law 95-87 on Mining Performance." The objective of the study was to analyze the impact of the Act and its regulations on mining performance in order to provide recommendations to alleviate the impacts identified, including identification of research needs. This paper presents some of the highlights of that report: projected cost increases; additional equipment needed for compliance; review of methods currently practiced or those which can be modified; and will focus particulary on equipment and technology applications.

Jan 1, 1980

Mineral processing plant operators are faced with the necessity to choose between many different possibilities for plant improvement. Only a few such possibilities, however, can be tested on the industrial site. Steady-state simulators make it possible to assess the effects of several different flowsheet modifications in a few days, thus helping the process engineer to make his choice implement the solution that seems the most appropriate and check it. The example described here is the crushing and grinding circuit of the Shila Gold Mine, jointly owned by CEDIMIN SA and BUENAVENTURA SA, in Peru. Several possible modifications for the purpose of increasing capacity have been simulated and the results assessed in terms of technical quality, investment costs and energy consumption. The best solution indicated by the USIM PAC simulator was implemented and gave a 20% increase in capacity with a pay-back time of two months.

Jan 1, 1993

By O. Ozcan

Oleic acid has been almost invariably used in the flotation of siliceous fluorite ores. The performance of oleic acid, however, deteriorates with carbonaceous fluorite ores. Oleoyl sarcosine developed recently has been found to produce results superior over oleic acid with ores containing high calcite contents. While the mechanism of oleate adsorption is usually considered as chemisorption involving calcium oleate formation on both calcite and fluorite, no mechanism has been so far proposed to explain the adsorption mechanism of oleoyl sarcosine. In this study, the selectivity of oleoyl sarcosine, as inferred from flotation, zeta potential and infrared measurements, is ascribed to the interaction of fluorine ion to the nitrogen via hydrogen bonding.

Jan 1, 1994

By D. J. DeLeo

In recent years the hue and cry of American industry concerning the pressure of foreign competition on the domestic marketplace has become all too familiar to most of us, as we are all well aware, the steel industry has not been exempted from this pressure, reduced production levels, work force cutbacks, and in some extreme cases, plant closings and company liquidations have resulted, new regulations governing imports and quotas have been enacted, foreign trade agreements reached, and more strict regulation enforcement practices undertaken, despite these, and other measures, the impact of aggressive foreign competition has not lessened, the concensus of numerous management consultants is that in order to successfully cope with these problems we must draw on all available technology to provide the tools which will enable us to enhance our management effectiveness, one area requiring particularly close attention in any mining operation is that of managing critical resources - namely time, energy and equipment in a fast and efficient manner, In mining, with critical resources deployed over a large geographical area, any degree of success involved with resource management is dependent upon knowing the current status of all work related activities, if we, as mine operators, are to be more successful in this area, additional tools are a necessity and modern technology has provided a multitude of new options from which to choose.

Jan 1, 1985

By K. H. Singh

The addition of new data and corrections can be made under the control of a simple editing session. All programs for this system are written in FORTRAN and executabe "MACROS".. After the addition of new data, the whole file Is reinitialized to update the binary file and cross-reference tables. Updating the binary file involves rerunning the initializing program. The creation of graphic plots like cross sections and plan views is menu-driven from a terminal and very user-friendly. Small files containing not more than 10,000 entries (survey and assay points) are suitable for this setup, particularly for computers with less than 2 Megabytes of real and virtual memory. The largest file processed contained 35,000 lines of survey and assay information and required 4 megabytes of virtual memory. Working with this size file slows down the time for the creation of plots and cross sections. Another independent system is more akin to a financial type of data base. It was installed in one Anaconda mine as part of the operation's inventory, warehouse, day-pay payroll, and purchasing data bases. It is a highly hardware-dependent system, in particular, IBM's CICS/VS (Customer Information Control System/Virtual Storage). This is a true relational data base that optimizes storage requirements, supports online inquiry, update, data entry, and data security. While this system has been tested and proven in accounting applications, it requires programming expertice in PL/I and other CICS utility programs. It is well suited for huge data bases (like the 35,000 lines of data), but cumbersome for small engineering files.

Jan 1, 1985

By F. Calizaya

This study summarizes the ventilation requirements for a highly mechanized P.T.Freeport Indonesia's underground mine operation in Irian Jaya, Indonesia. The Deep Ore Zone (DOZ) is a copper-gold deposit being developed underneath the current Intermediate Ore Zone (IOZ) mine. One of company's current plans is to prepare this mine for a steady oreflow of 25,000 tpd by year 2003. This study includes the estimation of airflow requirements for various mining activities, the design of major intakes and returns, the determination of airway resistances and specifications of fan duties. It also includes the results of air pressure/quantity measurements in existing airways and the standards stated by the current Indonesian mining law.

Jan 1, 1998

By J. Y. Hwang

Processing of fine mineral particles in a slurry is a difficult problem. Methods to make fine particles magnetic have been developed recently and may offer a solution to this problem. Particles of nonmagnetic materials can be selectively rendered magnetic through surface interactions with magnetic reagents. When adsorption occurs, the magnetic susceptibility of the material is increased. Magnetic enhancement at several orders of magnitude can be achieved. Selectivity of the adsorption can be controlled by the functional groups of magnetic reagents and various surface interaction mechanisms. This approach allows a new degree of freedom for the processing of fine mineral particles, even with conventional magnetic means. Separation of valuable minerals and filtration of slimes from tailing ponds and recirculated water are examples of the applications. Basic principles of this technology are discussed in this study.

Jan 1, 1992

By John Dean

"Pumping backfilling medium used to fill in holes and caverns in mines is challenging. The often viscous, high solids materials are extremely abrasive and can destroy pumping systems in a matter of days. While a number of options are available, using a progressing cavity pump can often be the best solution. High pressure and capacity capabilities, coupled with low wear rates, ensures reliable cost effective operation.Thickened slurry backfilling for underground/excavation mining applicationsVoids and caverns develop as a result of mining operations penetrating deep into the earth seeking natural resources. After extracting all the ore from a mine, operators need to fill in these voids to preserve the integrity of the mine structure. They do this by pumping in a backfill medium. Each mine uses a different mix of components for backfilling, depending upon the mine’s specific structural requirements and environmental concerns, particularly water requirements. Most backfill mixes contain cement, or another cement-like substance, that acts as a binder to hold the backfill medium together. This is combined with tailings (unused rocks and waste from processing and/or extraction), and may also include chemicals or other binders to increase the material’s strength.Backfill pumping challengesPumping the backfilling medium can be a significant undertaking. This process involves transporting very viscous and high solid materials; the mix may contain 60-80 percent solids. These backfill slurries are extremely abrasive and the viscous material can wreak havoc with pumping systems. The material’s paste-like consistency presents problems for standard centrifugal pumps often used in other mining applications.Added complexity is posed when trying to achieve the required pressure, which depends upon how far away the material has to be pumped. It is not difficult to meet the pressure requirements if mixing the backfill material close to the area to be filled. However, pumping from extreme distances can be problematic — a great deal of pressure is required to transport the material from the mixing area to a distant backfilling site. Ideally, operators should be as close as possible to where they are filling, so they can use a smaller pump with lower power requirements."

Dec 1, 2018

By K. H. McDaniel

An interactive mine ventilation simulation software program (WIPPVENT) was developed at the Waste Isolation Pilot Plant (WIPP). The WIPP is a U.S. Department of Energy (DOE) research and development project located near Carlsbad, New Mexico. The facility is designed to provide a permanent, safe underground disposal of U.S. defense generated transuranic waste in bedded salt. In addition to its regular functions, the underground ventilation system is engineered to prevent the uncontrolled spread of radioactive materials in the unlikely event of a release. To enhance the operability system, Westinghouse Electric Corporation has developed an interactive mine ventilation simulation software program (WIPPVENT). While WIPPVENT includes most of the functions of the commercially available simulation program VNETPC (copyright © 1991 Mine Ventilation Services, Inc.), the user interface has been completely rewritten as a Windows ® application and screen graphics have been added. WIPPVENT is designed to interact with the WIPP ventilation monitoring systems through the site wide Central Monitoring System.

Jan 1, 1996

By Circe Verba, Scott Montross, Jon Yang

This work is a first-order study to assess the suitability of an organic acid lixiviant to extract rare earth elements (REE) from coal preparation fines refuse sourced from a Pennsylvania mine with a total REE of ~ 300 ppm. The extraction of REE using an organic acid, in this case 0.1Mcitric acid and 0.5Mtrisodium citrate solution, is compared against 0.5M(NH4)2SO4, 1MHCl, 1.2MH2SO4, and 0.5Methylenediaminetetraacetic acid (EDTA). Ashing the coal waste material prior to leaching tests with the citrate solution nominally improved REE extraction. Buffered citrate solution recovered 7% of the total REE in the as-received Isabella Fines as compared to 11% in ashed samples, whereas (NH4)2SO4 extracted 5–6%, respectively. EDTA recovered up to 33%of the total REE, most likely due to the higher coordination chelate bond. Mineral acids, however, outperformed the organic acids on ashed material (16–52%REE recovery), suggesting that organic acids may not be a suitable competitive option for REE extraction from these types of feedstocks.

Jun 15, 2021

By A. W. Dickerson

Following on from many years of research aimed at improving the effectiveness of truck haulage operations in mines operated by BHP Minerals, BHP Research developed a concept for an Innovative Large Mining Truck, (ILMT) which has the potential to significantly improve the cost effectiveness of rear dump mining trucks. The ILMT concept reduces the empty vehicle weight dramatically, greatly reduces unequal rear tyre loading and improves ride and handling characteristics. The concept has been taken to the "proof of concept" prototype truck stage with the cooperative efforts of BHP Coal, BHP Research, Liebherr Mining Truck, Inc., Liebherr-Australia and Birrana Engineering. Testing of the prototype truck commenced at a coal mine in Queensland, Australia during May 1996. Preliminary results from the testing program are very encouraging. Expectations are being met and in some cases exceeded.

Jan 1, 1997

By C. L. Lin

A PC image-based on-line coarse particle size analyzer has been developed to measure particle size distributions under plant situations where overlapped particles are being transported on a moving belt conveyor. Although previous testing had shown satisfactory performance of this image-based system for separated particle size measurements (the non-overlapped case), it was necessary to modify original algorithms in order to solve the overlap problem and make the system suitable for plant operations. On-site testing has been conducted at a large copper concentrator in the southwestern U.S. for further investigation of the overlap problem.

Jan 1, 1995

By Lloyd B. Underwood

In the event of a sudden nuclear attack upon the United States, it is imperative that vital command and control centers have a high probability of survival. One such vital facility is the North American Air Defense Command Combat Operations Center at Colorado Springs, Colorado. Known briefly as NOW, this installation when completed will be housed in large chambers excavated out of granite beneath the eastern slope of Cheyenne Mountain (Figure 1). The NORAD COC, a U. S. Air Force sponsored project, will serve as the primary collection and evaluation center for data concerning unknown aircraft, missiles, or space vehicles, which might bring destruction to North America. The data will be fed into high-speed computers and electronic equipment from outpost sources - radar, ballistic missile early warning stations and picket ships throughout the world. Electronically controlled display boards will make it possible to evaluate the tracking data instantaneously and to take appropriate defensive action1.

Jan 1, 1965

By A. D. Wunderlich

Providing a safe & secure environment for your employees and other company assets is absolutely necessary in our litigeous society. Security hardware is no different than computers or other technical equipment, in that new equipment is developed each year that makes older equipment obsolete. This presentation will help to explain how your existing security system and security procedures can be updated to meet industry standards without the expenditure of a great deal of money. If you are concerned about potential security problems and how to address these problems, this presentation is a must.

Jan 1, 1995

Overland conveyor belts that exhibit tracking problems under loaded and unloaded conditions can be tested to' determine the root cause of the mistracking. Moveable conveyors are more prone to mistracking due to structure alignment requirements. In addition, belting quality, splice straightness and carcass condition has a dramatic effect on the performance of a belt in relation to tracking. Methods are discussed that are proven to reduce belt mistracking and improve the operational reliability of the conveyor system.

Jan 1, 1995

This paper summarizes the process development behind the design of three different types of paste fill plants at operating Canadian hard rock mines. Each application has a unique paste backfill mix and process which utilizes the materials economically available to the mine site. The different plants produce paste fill composed of base metal tailings, a blend of recovered disposal pond tailings fines and alluvial sand, gold ore tailings, and a blend of gold ore tailings and alluvial sand. This work has led to the joint development by Inco and GL&V Ontario of the compaction storage mechanism for the de-watering of mill tailings to a paste consistency.

Jan 1, 1994

By F. Stanley, A. Noble, G. Luttrell

"The supply chain for coal-fired power stations involve a multi-stage network of mining units, preparation plants, blending facilities and transportation systems. Attempts to optimize the supply chain have historically been difficult due to the lack of communication/coordination between the various groups involved in coal production, transportation and utilization. In light of this issue, a new approach for globally optimizing the coal supply chain called Micro-Price Optimization has been developed to simplify the optimization problem and to provide coal producers with fundamental insight needed to improve the profitability of their operations. This fundamental concept assigns unit values to each particles (or groups of particles) passing through production units. Optimization occurs whenever the maximum tonnage of positive value particles are recovered and passed to market, while the minimum tonnage of negative value particles are recovered. Elements considered by the concept include factors such as target boiler cost/efficiency, waste disposal costs, coal quality parameters, emission penalties, transportation charges, or other quantifiable impact factors. This article reviews the basis for the micro-price concept and provides a detailed industrial case study involving the determination of optimum coal qualities that need to be supplied by mine operators to feed a coal-fired power station. INTRODUCTION The performance of coal preparation plants have long been known to play an important role in determining the overall profitability of mining operations. This significance is due to the fact that the misplacement of just 1 ton/hr of clean coal to reject resulting from poor plant performance can represent nearly $300,000 per year in lost revenues for a mine producing a steam market coal (i.e., 1 ton/hr x $50/ton x 6,000 hr/yr = $300,000/yr). This loss can be even more pronounced, occasionally approaching $1 million per year for each 1 ton/hr of misplaced clean coal, for operations producing high-quality coking coal products sold into the premium metallurgical market (i.e., 1 ton/hr x $150/ton x 6,000 hr/yr = $900,000/yr). Detailed economic studies indicate that improvements in plant yield resulting from increases in organic efficiency have one of the largest overall impacts on mine revenue when compared to other cost centers within the mining operation. One of the first studies to show this important financial impact was reported by Norton-Hambleton Consultants (Norton, 1979). Their study indicated that an unfavorable change in plant efficiency was second only to coal transportation in terms of its impact on profitability, while an unfavorable change in the cost of underground mining was a distance third. This longstanding realization has continued to provide a strong financial incentive for coal producers to optimize the separation efficiency of their coal processing and blending operations."

Jan 1, 2015

By L. J. Vincze

The program of study of pellet binder materials was begun by the ORF in 1963 to examine various Canadian materials as substitutes for bentonite which is imported in large tonnages (199,270 tons in 1969) from the U.S.A. for Canadian pellet plant operations. Most of the raw bentonite used in Canada originates in Wyoming, North Dakota and more recently Greece, resulting in relatively high transportation costs to pellet producers. Some Canadian bentonites available in Western Canada (Alberta) can be beneficiated for uses as pellet binders but could not compete in cost with U.S. sources due to the cost of beneficiation and the higher rail transport charges to Eastern Canada. It is difficult to find a substitute for bentonite, and many materials have been investigated by research groups but, so far, no economic substitute is in use. However, some success is apparent in studies of low cost materials such as clays, sea weed, peat moss and low grade coal, The work done by the ORF over several years has covered systematic test¬ing of Ontario clays, lignite, some types of tree bark, waste sulphite liquors of various kinds, and peat moss as binders for iron ore pellets. The major effort has been concentrated on peat moss and has included a study of the influence of different additives. Since analysis of peat moss for humic acid is difficult and time consuming, a certain amount of time was devoted to development of improved methods, the most useful of which was a spectrophotometric method based on extraction of peat by sodium pyrophosphate for determination of humic substances. In the present paper, only the most recent work concerning the use of peat moss with suitable additives is discussed in detail, since it is the most conclusive and best documented portion of the program.

Jan 1, 1971

By B. A. Wills

Much research effort has been spent in attempting to reduce the high energy costs in grinding, but relatively little in developing methods to enhance the liberation of the minerals from each other. This paper presents some ideas on the nature and role of grain boundaries in mineral assemblies, and their influence on the propagation of cracks through the rock. It is argued that if the mechanisms of fracture are more clearly understood, crack propagation may be controlled in such a way that intergranular fracture dominates breakage, producing less fines and a higher degree of liberation.

Jan 1, 1995

By Frank C. Di Luzio

REMARKS BY FRANK C. DI LUZIO, ASSISTANT SECRETARY OF THE INTERIOR FOR WATER POLLUTION CONTROL, BEFORE THE ANNUAL MEETING OF THE AMERICAN INSTITUTE OF MINING ENGINEERS, NEW YORK CITY, FEBRUARY 25-29, 1968 POLLUTION PROBLEMS AFTER MUNICIPAL-INDUSTRIAL WASTE CONTROL I am happy to have this opportunity to discuss pollution problems related to the mining industry and the role of mining engineers in protecting our environment. Technological Power and Pollution of the Environment The increasing power of technology to destroy and disrupt the natural environment and the ecological systems upon which life depends has reduced man's margin for error in the use of this power. We must act, therefore, to deter and prevent the occurrence of future ecological disasters such as that caused on the British and French coasts by the sunken oil tanker, the TORREY CANYON, the Clinch River fish kill which occurred when a dam broke and released coal ash from a power plant operation, or that which threatened on the Clark Fork River in Montana when a strike at the Anaconda Copper Company threatened to shut down pollution control activities, thereby endangering fish and plant life on the Clark Fork River with copper waste. In the past, pollution of the environment has tended to be slow. But now, the increased power of technology to damage nature, the loss of in¬sulating space and the compression of time--all reduce our margin for error and the cushion which space and time once provided for our mistakes.

Jan 1, 1968