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By D Cai, E Baafi

Various enabling technologies and systems have recently been introduced in the mining industry. Such systems include miner-bolters with concurrent cutting and bolting, employment of two shuttle cars, adoption of self drilling bolts and utilisation of continuous haulage or monorail systems. The paper discusses how Flexsim discrete event simulation models were used to assess how these proposed mining systems can best be used to achieve and sustain high roadway development rates of 10 m per operating hour for 20 h/day.

Sep 26, 2011

By Kenneth N. Han

The authors investigate the use of froth flotation to remove carbonaceous material from Carlin gold ore. They also study the effect of type and concentration of various oils as flotation collectors and of sodium silicate as the dispersion agent on the overall recovery of carbonaceous material. And they examine other variables affecting froth flotation efficiency, including particle size, pH of the solution and temperature. Han and Chen also investigate the effect of reduction and oxidation of carbonaceous material on froth flotation efficiency. This investigation showed that aromatic type oil was the most effective collector. And the authors also found that oxidized carbonaceous material was difficult to float unless the oxidized portion was subject to reduction before flotation.

Jan 1, 1990

By Nico Sutmoller, Rich Palladino

Underground voids present a unique geotechnical engineering challenge. This paper will address materials and transportation mediums that are typically used for backfilling underground voids with native material. After reviewing traditional backfill and transportation methods, this paper will explore the advancing technology of foam transportation and the advantages of using this technology for transporting fill materials into underground voids to backfill them with Liquid-Sand. The paper will also review the benefits that Liquid-Sand brings to these applications and highlight specific case studies in which foam transportation has proven effective and provided cost-effective, environmental benefits.

Feb 1, 2025

By John Magyar

Special foamed cements were used to stabilize and secure caving ground in a newly-reamed 12.5-ft diameter underground ventilation raise. Two zones of very poor Rock Mass Rating (RMR) material were encountered during reaming of a ventilation raise at Placer Dome's Turquoise Ridge Mime in Northern Nevada These zones caved to large cavities, continued failing, and could not be safely secured using standard rock bolting, wire mesh, and shotcrete procedures. In stable sections of the raise, the ground control plan called for the contractor to install 8-ft and 124 length resin grouted No. 7 Dywidag bolts, chain-link fence mesh and shotcrete. This work was conducted on three decks installed on the raise bore reamer. The first of the caved areas was approximately 1,500 cubic yards in volume and extended out to 40 ft beyond the wall of the raise. Placer Dome considered several options for structural fill to repair the area including pumped shotcrete, concrete, and placing and grouting aggregate. A safe, cost effective, and expedient method of stabilizing the raise with foaming grout and bolted liner plate was selected and successfully executed. The special fast-setting, foaming cement grouts used were Tekfoam and Tekseal® manufactured by Minova. The raise was quickly placed in service. Factors considered in selecting the foaming grout are discussed.

Jan 1, 2005

By S. C. Lamey, P. A. Hesbach

This study evaluated the use of regionally produced coal combustion products to neutralize and remove metals from acid mine drainage (AMD). Synthetic AMD mixtures were treated with a number of fly ashes and fluidized bed combustion (FBC) ashes. All of the ashes reduced the volume of the sludge produced and gave a faster settling rate than the sludge produced by treatment with lime. Faster settling allows greater throughput rates. In addition, the FBC ashes, which generally contain alkaline components used for sulfur capture, completely neutralized the acidity and, if desired, raised the pH above 10. The fly ashes, on the other hand, reduced the final volume of sludge but required additional neutralizing agents to attain a pH >5. The pH of the AMD can be taken to above 10 to insure complete removal of manganese, or it can be taken to a more neutral pH of 7 or 8 to allow for the safe introduction of the aqueous phase into ponds or streams. The process combines two industrial waste products to reduce the disposal volume of one of the waste products and to produce an environmentally safe aqueous discharge.

Jan 1, 2002

By P. J. Poirier, J. A. Meech, H. Raabe

"An Expert System has been implemented to assist operators in applying knowledge about froth conditions in the control of the flotation circuit at Highland Valley Copper. For some time, the personnel at Highland Valley Copper have recognized that froth type is a useful indicator of good operating conditions. However, the operating strategy based on froth type recognition is an ad-hoc skill in which different operators use a variety of terms, features and procedures to identify and solve problems. The first phase of this project developed an on-line consultative system to advise and tutor so that the diffuse expertise could be rationalized and consolidated into a standardized format.The second phase has brought this knowledge into a real-time environment to advise the operators on the floor in identifying froth types and troubleshooting corrective action. This paper describes the steps taken to acquire the knowledge, to design the required system features and to implement the real-time version of this system.INTRODUCTIONThe use of expert systems in the mineral industry has been gaining popularity in recent years. Minnova Inc, Les Mines Selbaie, Wabush Mines, Potash Corporation of Saskatchewan are just a few examples of Canadian mining companies that use expert systems to monitor or control their plants. Applications in the field of flotation include Brenda Mines (Edwards, 1992), Mt Isa Mines Ltd (Lacouture et al, 1991), Outokumpu (Karhu, 1989) and Kidd Creek (Burrows et al., 1989).Expert systems are defined as ""computer systems that apply reasoning methodologies on knowledge in a specific domain in order to render advice or recommendations much like a human expert"" (Turban, 1988). The main areas of application are diagnosis, training, process monitoring and control, and design. There are basically two main types of expert systems: Consultative systems, which are off-line applications in diagnosis and design, and on-line realtime systems, used for supervisory process control and real-time advising."

Jan 1, 1993

During 1991 - 1993 the author interviewed approximately thirty senior managers of varying responsibilities in either the engineering, construction or operation of a heavy industrial facility. The purpose of the exercise was to determine the factors driving a deterioration of the working relationship between the engineering and the operating company following practical completion of a major project. From the research a number of conclusions have been drawn as to the root cause of the deteriorating relationship. For this paper we are drawing on this initial research and our ongoing experience of solving problems of this nature to present some fundamentals that can be used to break the breakdown maintenance cycle.

Jan 1, 1998

By Tanveer Jahir

With increasing energy costs and mounting government pressure to adopt low emission, green sources of energy, it has become imperative to develop long-term sustainable underground infrastructures that exhibit low power consumption. Underground mining environments are mandated to have ventilation systems in place to replace polluted air with clean air. Continuously running air ventilation systems have proven to be an expensive solution for this requirement. Ventilation-on-demand (VOD) is a cost effective method for not only reducing energy consumption and greenhouse gasses, but also ensuring the safety and well-being of the miners beneath the surface. VOD is achieved by monitoring the air quality in target areas of the mine, and based on variables such as the number of personnel in the area, the number of emission-emitting vehicles, the air leakage around doors and entrances, dust levels, and other key environmental details, the speed and angles of the fan blades are adjusted to increase or decrease the volume of air flow. For over 40 years, Conspec Controls has been developing systems capable of VOD through the use of controllers, gas monitors and personnel/vehicle tracking equipment, providing inexpensive, reliable solutions for underground ventilation.

May 1, 2011

By Li Rongxing

A general regular solution model put forward in this paper defines a general interaction parameter that includes both composition and temperature dependence. On the basis of this model, analytic express of solution excess properties was obtained by least square fit using the composition and temperature relations in binary alloy phase diagram. After some solution excess properties analytic expresses of correlated binary alloy system obtained, the analytic express of ternary alloy system could be obtained by superposition of general geometrical model. The ternary alloy system Pb-Sn-Zn has been predicted in terms of this method and the result was very in agreement with actual measured value.

Jan 1, 2006

By Valentine Chanturiya1

We have developed a classification of geochemical barriers according to their origin, i.e. natural and artificial, and according to methods and areas of application. There has been an examination of the interaction between different classes of geochemical barriers with sulfate solutions containing nickel, copper and iron. As natural barriers, carbonates (calcite and dolomites) were used. For artificial barriers, a mixture of serpentine and carbonatite, thermo-activated copper-nickel dressing tailings, and a magnesium-containing sorbent based on brucite was used. Keywords: geochemical barriers, physical-chemical geotechnologies, treatment of natural and waste water, recovery of nonferrous metals

Sep 1, 2012

The La Colosa, Colombia porphyry gold deposit is currently in the pre-feasibility stage. This large deposit has many types of gold mineralization: native gold, electrum, and tellurides. These variations in the gold mineralization lead to variability in the gold recovery. The final process flowsheet may include gravity concentration with cyanide leaching. Metallurgical testwork is utilized to identify the zones of ore that may be problematic to recover. To help select the samples that represent the fluctuating variability zones, geometallurgical models are constructed using mineralogy and geology data. These zones are then wireframed and compared to the geological and structural models for spatial correlation. Samples for the variability testwork will be selected from these different zones to identify and analyse the effect the different gold mineralization types have on the recovery. By using geometallurgy to aid in the sample selection for metallurgical testwork, the variability in the ore body can be understood and constrained to aid in process optimization.

Feb 27, 2013

By D Olwagen, C Stanton, J Gerber

From December 2013 to February 2014 the Southern Middleback Ranges magnetite concentrator went through a successful optimisation process that included the installation of extra grinding power to treat a wider range of ore types. After the initial improvements, sampling surveys were conducted to identify the mineral deportment through the concentrator. Samples collected during the survey were analysed using X-ray fluorescence, quantitative X-ray diffraction and QEMSCAN™ to cross-validate the analysis. Certain streams were also put through a laboratory-scale Davis Tube Recovery washing process to produce clean concentrates for analysis. The QEMSCAN™ analysis identified various metallurgical characteristics (mineral association, particle sizes, grain sizes, particle densities, etc) and these were evaluated for each separation and comminution stage to both understand the processes involved and identify opportunities for improvement. Key findings from the investigation indicated the importance of understanding the elemental deportment of target elements throughout the various minerals. The standard practice of tracking iron deportment through assay provided misleading results on losses to tail through the plant. The investigation provided insight into both wanted and unwanted minerals and the efficiency of each separation stage. The efficiencies of separation are critical due to their impact on downstream capacity, and the investigation provided insight into where opportunities exist to extract more benefit. The findings of the geometallurgical analysis have been implemented on the concentrator, and improvements in the rejection of non-magnetic minerals have been seen.CITATION:Gerber, J, Stanton, C and Olwagen, D, 2015. Using geometallurgy during process optimisation activities at the Southern Middleback Ranges magnetite concentrator, in Proceedings Iron Ore 2015, pp 561–566 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By C. B. Clemmens

Accurately predicting ground control conditions before mining requires a comprehensive exploration approach including photogeologic mapping (satellite and low altitude), delta modeling and, particularly, geophysical logging. In situ properties, density; strength indices; grain size; clay content; and aquifer location, can be estimated with this inexpensive technique. Geophysical measurements can be spot-checked by field or laboratory tests on core samples and by hydrologic (pressure) testing. Each phase of drilling should be accompanied by refinement of the delta model, facilitated by log signatures. Measured properties can then be projected into geologically similar areas. A properly planned program will delineate both the "worst-case" and normal support conditions. Suspect areas can be avoided by mine layout and the mine plan can contain support contingencies for anticipated trouble spots.

Jan 1, 1985

By William P. Walsh

In December 1983 the author undertook an investigation in east Texas which was organized to learn the feasibility of applying geophysical techniques over shallow lignite deposits. The work embraced experimental high resolution seismic reflection and offset Wenner resisitivity sounds over three 4 to 4 mile test sections. This site also was sponsored by Woodward-Clyde Consultants (WCC) and a consortium headed by North American Coal Corporation. The principal objective of this investigation was to learn whether the aforementioned geophysical techniques could be applied over shallow lignite deposits (i.e. located at approximately 100' to 300' in depth) and consequently provide structural and stratigraphic information useful for resource and reserve characterization. A secondary objective was to determine if these same techniques could disclose the nature of the overburden and the distribution of ground water therein.

Jan 1, 1985

By William P. Walsh

In December 1983 the author undertook an investigation in east Texas which was organized to learn the feasibility of applying geophysical techniques over shallow lignite deposits. The work embraced experimental high resolution seismic reflection and offset Wenner resisitivity sounds over three 1/4 to 1/2 mile test sections. This site also was sponsored by Woodward-Clyde Consultants (WCC) and a consortium headed by North American Coal Corporation. The principal objective of this investigation was to learn whether the aforementioned geophysical techniques could be applied over shallow lignite deposits (i.e. located at approximately 100' to 300' in depth) and consequently provide structural and stratigraphic information useful for resource and reserve characterization. A secondary objective was to determine if these same techniques could disclose the nature of the overburden and the distribution of ground water therein.

Jan 1, 1986

By Anshumali Gangwar

This paper outlines the chance constrained binary integer program developed by the author in his doctoral dissertation at Columbia University, New York, 1973. The optimum planning of a mining program involves the determination of a production schedule which maximizes the net present value of the mining property. The actual mining process has an inherent stochastic and discrete nature. In particular, the demand for the mined product and the grade of the mineralized material in the ore are the two most important stochastic mining variables. The decision to mine or not to mine any block of a mining property is a binary integer variable. This paper outlines the formulation of pit production scheduling problem as a chance constrained binary integer program. The deterministic equivalents of these chance constraints are nonlinear in binary variables which have subsequently been linearized. The planned objective is to meet with a stipulated high degree of reliability, all the random demands as they materialize with a random supply of the commodity being marketed as determined by the eventuating random grade values of the exposed ore blocks and the mining system's production constraints such that the discounted total production costs over the entire planning horizon are minimized or the profits maximized. The emerging surface of the mine in each scheduling period is determined by the values taken by the binary decision variable associated with each block of material in each scheduling period.

Jan 1, 1982

By T. D. Murphy

In the fall of 1988 it became evident that the accuracy of sulfur forecasts for Monterey Coal's No.1 Mine needed to be improved. In addition, it became necessary to predict if any individual train shipments during a month would exceed a contract sulfur limit. The challenge was to develop a forecasting process that would take into account the variability of the coal in the ground as well as the difference between laboratory and preparation plant sulfur reduction efficiency, and the effects of mining coal with multiple units. This paper describes how geostatistics and simulation techniques were used to meet this challenge.

Jan 1, 1992

By Kelly D, Moore C

The Golden Mile, which has been mined continuously for the past 100 years by both underground and more recently open pit methods, occupies an area of 1.2 km by 4 km adjacent to the city of Kalgoorlie Boulder in Western Australia (Figure 1). Large-scale open pit mining at the Kalgoorlie Consolidated Gold Mines (KCGM) Fimiston operations is currently extracting 7.8 million tonnes of oxide and sulphide ore for a total production of 522 000 oz per annum. The effectiveness of grade estimation techniques at KCGM has been examined with reference to existing 10 m bench sample data from all operating areas within the Eastern Lode System of the Main and North pits. The aim of the study was to recommend practical parameters for grade control estimation. The review included comprehensive variography and comparison of nonparametric estimation methods (Joumel, 1983) such as indicator kriging and probability kriging with ordinary kriging, leading to the development of improved grade control parameters and procedures for both daily quality control and short term mine planning. This paper reviews the geological, statistical, geostatistical, mining and modelling features studied in order to present KCGM's Mining Department with recommendations for improving grade control.

Jan 1, 1994

Stringent controls now placed on the quality of coal make it important to be able to predict not only the tonnage and the grade of the coal in situ, but also the recovery factory and average grade after the coal has been washed. The established techniques of linear geostatistics (ordinary kriging) can be used to estimate the total tonnage and the grade of the coal in situ, but more sophisticated techniques are required for predicting the characteristics of washed coal. Two approaches are currently being investigated at Fontainebleau. One involves a parametric model of the washability curves and disjunctive kriging. This is described in Armstrong (1980(a) and (b)). The other is similar to the service variable approach used for estimating recoverable uranium reserves. The method is described in this paper.

Jan 1, 1985

By Margaret Armstrong

The increasing cost of developing new mines and the need to mine more marginal deposits have led mining companies to use more sophisticated estimation methods such as kriging. But until recently, coal mining companies have shown little or no interest in these techniques. However, the stringent quality controls which are now placed on coal have led to a surge in interest in improved estimation methods. This can be seen from the -, number of research projects by private companies and governmental agencies on the application of geostatistics to coal reserve estimation. At present, most of these programs are centered on the problem of estimating the tonnage and the average grade (i.e. ash percent, sulphur content, calorific value, etc.) of the coal in-situ. See, for example, Sabourin (1975), Woods (1976, 1979), Pauncz and Nixon (1979) and Armstrong (1980). These studies show that the established techniques of linear geostatistics can be applied successfully to coal deposits. The study by Woods is particularly interesting because he had access to the actual production figures as well as the initial sample data from the no 2 seam in the Greenside Colliery owned by the Anglo-American Corporation. He showed that the estimates obtained by kriging were consistently closer to the actual production figures than those given by three other estimation methods. This confirms the superiority of kriging as a method of estimating block values for coal. Another advantage of geostatistics is that it can be used to determine the optimal spacing between drill holes. An example of this is given by Armstrong for the coking coal deposit in the Bowen Basin, Australia.

Jan 1, 1981