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By D. Royston, D. Denlay

Pulp lifters are used to discharge ground pulp from non-overflow grinding mills. In straight-radial channel pulp lifters, discharge is often incomplete and back-flow down the pulp lifter can occur. Leading-curve channel pulp lifters can be used to ensure complete discharge, especially at high mill rotational speeds. The complex motion of solid materials in pulp lifters has been modelled mathematically for both straight-radial and curved pulp lifters in order to make comparisons between the two types. The model is supported by practical observations of the performance of curved pulp-lifters in a commercial 24ftSAG Mill as well as observations of the discharge from several commercial straight-radial pulp-lifter AG/SAG Mills.

Jan 1, 1999

By Alwyn Protheroe, Steve Smith, Herbert Jr. Gibson

In September of 2000, Cowin and Company, Inc., contracted with Paramont Coal Corporation to construct a large decline approximately 820 m (2,700 feet) in overall length at a grade of 8 degrees to the Lower Banner Coal Seam. This paper will discuss the methods used by the contractor and owner to overcome the unique problems required to construct this tunnel in a coal mine environment. The problems include, initial design considerations, equipment selection, ventilation, ground control, control of water in?ows, and placement of concrete.

Jan 1, 2003

By Dominigue Francois-Bongarcon

This paper presents a step by step vulgarized review of the applications of geostatistics to the estimation of the mineable, recoverable reserves of the Cinola gold deposit in British Columbia.

Jan 1, 1988

By C. J. Bise

Safety training requirements differ from mine to mine due to changes in the demographic characteristics of the workers or changes in job and organizational characteristics. Accordingly, a microcomputer-based procedure has been developed to assist mine trainers is determining if undesired worksite performances result from lack of knowledge or skill, which are trainable categories, or from categories that are considered to be non-trainable (such as equipment limitations or management procedures). A special effort was made to understand the psychology of worker behavior by analyzing worker reactions to various organizational and job characteristics.

Jan 1, 1995

By Trevor J. Smith, Kevork A. Chouzadjian, Rob S. Burns, Steve J. Roden, Michelle A. Spieth

Investigations were undertaken to improve the recovery of silver from CRA's Hidden Valley gold/silver deposit by the addition of calcium peroxide. The addition of 0.75 to 1.5 kg/mt of calcium peroxide improved silver extraction by 5 - 300 and reduced cyanide consumption by up to 30%. Gold extraction was also marginally improved in some of the tests. The results are of economic interest and plant trials will be initiated once operations are underway.

Jan 1, 1990

By Tad S. Golosinski

The paper presents the computing stream of the mining engineering curriculum at he Western Australian School of Mines (WASM), a branch of Curtin University of Technology. Learning to use computers begins during the first semester of the initial year of studies and culminates in the Mine Design Project done during the last semester of study. It covers all areas of computing which are judged to be of importance to the graduate.

Jan 1, 1996

By J. B. Rubinstein, V. J. Badenicov, S. T. Hall

A simulation technique of the flotation process and models for the solution of various problems are developed. A modular model of column flotation is constructed taking into account the kinetic relationship of the process and the hydrodynamic regime in the cell. Based on this, a technique of calculating the column parameters based on laboratory tests is developed (scaling-up), and applied for calcetest results is developed (scaling-up), and applied for calculating the design of commercial-scale columns.

Jan 1, 1996

By Lynn B. Hales, Randy A. Ynchausti, Robert W. Colby

Process control systems have evolved from single loop control to distributed control with computer based expert control strategies. The next step is to add adaptive control to the expert control strategies. An object-oriented intelligent adaptive optimization approach is defined and simulated results are presented.

Jan 1, 1995

By Maurice Deul

Limestone can be used effectively in treating acid mine water. Aside from a lower cost than for other treatment agents, limestone has the advantages of easy storage and effectiveness even when impure and in slack sizes. Limestone incorporated into waste piles in layers or as riprap can inhibit acid formation; limestone rubble packed in a mine entry offers promise in formation of a low-cost autogenous resilient seal.

Jan 1, 1974

By D. C. Panigrahi

The paper presents the application of Object Oriented Programming approach for the development of a network simulation model based on nodal pressure method using linearised flow equations. The convergence and computational efficiency of the algorithm have been investigated. Finally the paper re- ports the validation of this algorithm in actual field conditions.

Jan 1, 1996

By T. R. Ellis

The author is the leader of the Extractive Industries Task Force of the International Valuation Standards Committee. The Task Force has developed an Extractive Industries section for inclusion in the International Valuation Standards (IVS). The Extractive Industries Guidance Note provides comprehensive standards for valuation of all minerals and petroleum industry property types for all valuation/appraisal purposes. The document is scheduled for release as an exposure draft for public comment by December 2003, then it will be finalized for publication in the IVS in mid-2004. This paper discusses the content and philosophy of the Extractive Industries Guidance Note within the context of the framework of the IVS. It also discusses the international implications and implementation of this IVS addition.

Jan 1, 2004

By Loren G. Thompsen

The first high pressure grinding roll in a copper mine was commissioned at Cyprus Sierrita in July 1995. This grinding roll is the world's biggest operating unit. It has a roll diameter of 2.4 meters and a face width of 1.4 meters. It is driven by two, 2250 KW (3,000 HP) motors. This paper will discuss the development of the grinding roll at Cyprus Sierrita and what it has done for comminution of Sierrita ore. Maintenance and operating performance will be discussed as well as testwork including size reduction, power input, work index, and throughput.

Jan 1, 1997

By M. Mohammed, S. J. Jung

The prime criteria in the design of underground openings with complicated geological structures is ground control. Stability of underground openings for deep mines is critical because incorrect orientation or geometry of the shaft, stopes and accessways often results in the failure of openings due to high stress conditions. Current design procedures for complicated orientation and geometry of mines are rapidly becoming inadequate. In this study, the finite element method (ANSYS) has been used with optimization criteria to design safer, more stable underground openings.

Jan 1, 1995

By Dale R. Ralston, Roy E. Williams, Gerry V. Winter, George L. Bloomsburg

Jan 1, 1986

By K. J. Stanaway

Environmental pressures on waste disposal are forcing pigment producers to use feedstocks with higher Ti02 content and lower levels of trace elements. Despite this, 50% of the world's Ti02 comes from ilmenite concentrates with only 37% to 54% Ti02. An industry growth rate of 25% in the next 10 years, combined with trends to diminishing resources and lower mining grades for rutile (95% P02) and leucoxenized ilmenite (55% to 90% P02), means that unless new discoveries are made soon, the industry will become even more reliant on ilmenite.

Jan 1, 1995

By Jim Avraamides

The properties of activated carbon which are important for gold recovery applications include activity, capacity, wear resistance, particle size distribution and bulk density. There are experimental difficulties in attempting to simulate the plant environment in the laboratory in order to measure the above properties. However, standard tests can be set up to compare the characteristics of different carbons and to assist in monitoring the performance of carbon in CIP operations. These laboratory tests are critically evaluated and data are presented on the performance of carbon from a number of CIP plants.

Jan 1, 1989

By V. P. Keran, K. Leung

Two 32 foot x 14% foot, 6.4 MW autogenous mills have been installed in the Mount Isa Mines Copper Concentrator to replace the fine crushing plant, fine ore bin, rod mills and primary ball mills. This paper describes the reasons for the change, the rationale for the new circuit design and configuration, the design and scale-up processes used to size the mills, considerations for the installation of large mills inside an operating concentrator and some early operating data.

Jan 1, 1992

By M. Karmis

The Virginia Center for Coal and Energy Research is leading an interdisciplinary coalition to identify potential carbon sequestration sinks in unmineable coalseams as part of the U.S. Southeast Regional Carbon Sequestration Partnership. The Virginia Center for Coal and Energy Research and the Eastern Coal Council are leading education efforts for the project, as well as specific outreach efforts in Central Appalachia in order to develop a process for stakeholder education and engagement in sustainable energy.

Jan 1, 2007

By N. Powell, C. F. Spollen, B. A. Wills

A discussion of the practicalities of carrying out a material balance using simple nodal sensitivity analysis is given. The calculation of the errors involved is reviewed and the concept of co-variance examined through computer simulation. The use of co-variances in such calculations is shown to be practically insignificant. The method proves to be rapid and relatively accurate provided the circuit topology is correct.

Jan 1, 1991

By Earl F. Mathers

Few people would question that coal is king in the Campbell County, WY area. Other industries, such as oil production and ranching, also contribute significantly to the economic base, but coal mining and related industry development dominate. In recent years, Gillette has become the commercial hub of northeastern Wyoming. This development has been largely a response to the growth of the coal industry in Campbell County. Historically, Campbell County developed as a ranching area, a process that was aided by the passage of rail lines through the area, allowing early ranching interests to get their livestock to market. For decades, the Gillette-Campbell County area was predominantly a ranching area that experienced only incremental population growth.

Jan 1, 1994