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By Kurt Westerlund

Cooling of hot sticky gases with solids in a circulating fluidized bed called FLUXFLOW is described. Fluxflow is used for gas streams from metallurgical reactors, e.g., Isasmelt copper in Australia and TBRC for lead in Sweden. The features and potential of this technology in metallurgy and waste treatment ie described. The FluxfLow la a new, cost efficient high availability solution to treat hot sticky gases that has made new gas handling and heat recovery flow sheets available to the process industry.

Jan 1, 1994

By T. Hayes

Track-type tractors remain one of the most cost-efficient stripping tools available to coal miners. Whether they are "sweetening up" a dragline operation with pre-benching or serving as the primary stripping tool, dozers can play an important role in driving down mining costs. This paper reviews the application zone of track-type tractors. In addition, it provides tips on site set-up, equipping of tractors, and machine operation which the audience can take home and apply.

Jan 1, 1996

By David C. Slack

In recent years public concern over the environment has grown enormously. A very aware populace has exerted pressure on its legislators to enact enforcement laws dealing with pollution. Among the different types of pollution, sulfur dioxide in the air is a large and readily identifiable constituent. Air pollution, according to the EPA, costs the U, S. billions annually with SO2 a major portion of this cost. Fossil fuel and oil fired power plants release better than 50% of the SO2 in the country. Thus great attention is being focused on the methods power plants are utilizing to control emissions. With a time schedule of compliance by early 1975, decisions are being made and systems chosen that will have to perform - and perform - and perform. Therefore, a large majority of the power plants are presently considering lime in the planning and operational phases of their stack gas desulfurization programs. The reasons for this are: Lime scrubbing has more development and pilot work completed than most other methods; the removal potentials are relatively high; the stoichiometric ratios are not excessive and, the process has relatively low capital and operating costs. Many pilot plant studies have been completed recently using lime and the first operational full scale lime scrubbing unit is now in the start-up phase at this time at Duquesne Light Company's Phillips Station here in Pittsburgh. Also, because of completed development work, the problem of solid waste disposal will also be tackled at this power station at the same time. There are various methods for the use of lime in scrubbing for S02, but for our purposes I would like to describe the cyclic wet lime process. This method called "Scrubber Addition of Lime" involves contacting the flue gas with a slurry of milk of lime.

Jan 1, 1973

By O. Schumacher

Guidelines for publication of information defining the amount and grade of resource material available in a deposit are well established in Australasia?s JORC Guidelines, Canada?s National Instrument 43-101 and similar documents in South Africa, Peru, Chile and elsewhere (Table 1). These guidelines provide standards to apply regarding the geologic and geostatistical basis for describing the level of confidence to be assumed for an estimate of the amount and grade of material. All of them provide for a strict distinction between material that has been demonstrated to be economically mineable and that which has not, and all of them provide terms such as ?resource? or ?exploration information? to be applied to data regarding material that has not been demonstrated to be economically mineable. It is not until an economic study has been completed that we are allowed to apply the powerful terms ?reserves? and ?ore? to our deposit material. Indeed, the application of these eye-catching labels immediately tells the reader that an economic study has been completed by a qualified person, and that the results of the study were positive. While extensive guidelines are established for describing the level of confidence in published geologic data, and the nature of the economic study that should be accomplished before using the terms ?reserves? or ?ore?, surprisingly little guidance is provided regarding the process to use, and the level of detail to attain, for estimating capital and operating costs for the study. The intent of this paper is to lay the groundwork for development of suitable guidelines for the cost estimating process. While the codes do not provide specific instructions for the cost estimate, they do provide numerous hints and clues to help determine the level of detail expected and the type of procedure to apply in preparing the estimate. This paper will first review the various codes to gain an insight into the thinking of the drafters of the codes regarding their unstated expectations for the cost estimating process. Based on this review, a series of guidelines are proposed for this purpose.

Feb 27, 2013

By James E. Breland

Society's growing concern over the number of deaths and serious injuries occurring in coal mines, coupled with a growing sentiment to develop and promulgate improved mandatory health or safety standards, was no doubt the basis for passage by Congress of the Federal Coal Mine Health and Safety Act of 1969, being Public Law 91-173 approved December 30, 1969. Even prior to passage of the Act, strong reaction was quick to arise concerning the effect of such legislation upon the coal mining industry. Initial response varied from mild forms of criticism to' the expressed fear of complete suspension of operations and mine closings. Primarily responsible for these early forms of skepticism were speculative or fanciful cost estimates which led operators to contemplate a less than prosperous existence. However, in spite of this unfavorable outlook, the majority of the operators have faced up to the situation and have been striving to comply with the Act and the regulations issued thereunder. While encouraging strides have been made toward implementation of the Act, it must be recognized that noticeable results have been attained only through many months of determined effort and, as anticipated, at quite heavy expense to the operator.

Jan 1, 1973

By Bruno C. Boik

INTRODUCTION Cost Management is the evaluation and control of project scope, budgets, and costs with the objective to minimize costs and maximize the benefits to be derived from the use of project resources in conformance with Criteria stipulated or approved by the Owner. In order of importance, Cost Management is one of the most prominent Project Management functions because of its impact on the financial success of the venture. Cost Control and Cost Accounting are essential parts of Cost Management. The principal objectives of Cost Control are to monitor project commitments and expenditures, and measure performance for the detection of variances from acceptable standards and from control budgets so that timely action can be initiated to minimize costs. Cost Control is evaluation of current costs and projection of future costs, rather than the reporting of actual costs. Cost Control is not Cost Accounting. The primary objectives of Cost Accounting are the determination, classification, analysis and reporting in useful detail of actual costs. Following are some considerations on Cost Management and Cost Control as practiced by Owners and Contractors of industrial projects, Mining and Metallurgical projects in particular. COST MANAGEMENT Functions Conforming with the requirements of Owner's Criteria, the principal Cost Management functions are to • evaluate estimates of project costs and establish budgets for a scope of work and schedule; conversely, evaluate the scope of work that can be executed most effectively within a budget and schedule. • promote investigations and comparative evaluations of alternate designs and plans to find the most cost effective way to execute a project and minimize its operating costs. • based on Cost Control and Cost Accounting input, evaluate and initiate appropriate actions to correct deviations from approved budgets. assess project economics, the effect of changes on project economics and, if necessary, revise Project Criteria to modify their impact on costs.

Jan 1, 1986

By B King

Processing expansion options and mining fleet purchases are major cost items that receive due focus in most cost management analyses. If these items are not needed, they can significantly reduce a project’s short-term capital spend and improve profitability and value to shareholders. When conditions change prior to purchasing equipment, the purchase may no longer represent the best decision for the project.This paper outlines a structured approach for making major cost decisions to improve the value of a project, determining which items should be kept and which should be eliminated.CITATION:King, B, 2014. Cost management optimisation, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 7–12 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By M. Z. Emad, S. Raza, K. Jalil, M. A. Raza, M. U. Khan, S. A. Saki

Dimension stone mining is Increasing because of growing demand from the building and construction industries. Diamond wire saw cutting is a popular dimension stone mining technique around the world. Estimation of the production cost for this method is critical for these operations. n this research a production cost model was developed for the mining of granite using a diamond wire saw. Cost and production data were collected from a granitic dolerite operation in Pakistan for a 4.5-year period, and analysed to identify the cost components. Fuel (34%), labour (15%), consumables (40%), and maintenance (5%) were found to be the four major cost components in this operation. A regression-based dimension stone production cost model incorporating statistically significant variables was developed. The data presented a strong correlation of production cost with fuel, labour, and consumables costs. Finally, a production cost model based on the consumption cost of diamond wire is presented. The model was verified using actual production cost data, which indicated 95% (R2 = 0.95) variance in the data between the predicted and actual production cost values. The model may help field engineers in computing their dimension stone operational cost during the cutting phase.

Nov 6, 2023

By D. W. Alexander

Mine fires, explosions, spontaneous heating and inundations are among the leading causes of catastrophes (unplanned, temporary sealing and recovery of major mines). Many reports are available that detail company efforts to re-establish mining operations and agency efforts to regulate away the causes, but the associated costs are rarely included. The increasing scale of coal operations concentrates earning potential and the financial risk of business interruption in fewer locations. Underground coal mine catastrophes are low probability, high loss events that happen nearly every year. This paper will present an evaluation of coal mine catastrophes from case studies.

Jan 1, 2003

By L. B. Rothfeld, R. L. Dolzani

This paper presents preliminary results of a US Bureau of Mines (USBM) study of potential costs of compliance with possible federal regulations for copper heap and dump leaching. The regulations could arise under amendments to the Resource Conservation and Recovery Act (RCRA) and/or the General Mining Law. Estimates are given for the cost of compliance with possible technology standards that would require the use of liners and closure caps regardless of terrain and underlying geology and hydrology. This cost is compared to the cost of compliance with 1992 state requirements for terrains typical of those found at existing copper leach sites in the southwestern United States. Incremental compliance costs are found to widely exceed screening criteria used by the US Environmental Protection Agency (EPA) to denote significant economic impact.

Jan 1, 1995

By L. B. Rothfeld

This paper presents preliminary results of a Bureau of Mines study of potential costs of compliance with the federal Resource Conservation and Recovery Act for copper heap and dump leaching. Specifically, estimates are given for the cost of compliance with possible technology standards that would require the use of liners and closure caps regardless of terrain and underlying geology and hydrology. This cost is compared to the co lit of compliance with present state requirements for terrain a typical of those found at existing copper leach sites in the Southwestern U.S.A. Incremental compliance costs are found to widely exceed screening criteria used by the Environmental Protection Agency to denote significant economic impact.

Jan 1, 1993

By L. B. Rothfeld

In anticipation of RCRA reauthorization and subsequent rulemakings, the Bureau of Mines is studying potential economic impacts of RCRA on mining. For U.S. copper heap and dump leaching operations in a variety of terrains, the cost of liners and closure caps to comply with RCRA Subtitle D ranges from $55 million to $158 million per site, or about $500,000 per hectare ($200,000 per acre). If RCRA technology requirements and financial assurance had been required on current operations, 27 to 100% of production from heap and dump leaching would have been non-competitive at market prices between $2,310 and $1,650 per metric ton ($1.047 and $0.75 per pound) copper. This result is based on an analysis that considers return on capital, corporate overhead, marketing, and freight costs as well as operating and maintenance costs at the mine. Over the same price range, economic analysis using the IMPLAN input-output model on one-or two-county regions indicates potential net job losses of about 570 to 2,700 jobs. Total economic output of those counties could be reduced by about $180 million to $360 million.

Jan 1, 1994

By Lebeau M., P. Duguay

"The cost of occupational injuries and diseases in the mining industry in Quebec was estimated for the period of 2010 to 2012. The method used takes into account the financial and human costs assumed by employers, workers, and the community. To better direct research and prevention toward issues with the most significant consequences, the results are presented in various ranking tables, which stakeholders might find useful.RÉSUMÉ Le coût des accidents du travail et des maladies professionnelles dans l’industrie minière au Québec a été estimé pour la période 2010-2012. La méthode utilisée prend en compte les coûts financiers et humains endossés par les employeurs, les travailleurs et la communauté. Afin de mieux orienter les recherches et la prévention vers les problèmes ayant les plus graves conséquences, les résultats sont présentés dans divers tableaux de classement, qui seront d’une grande utilité aux parties prenantes. INTRODUCTIONThe mining industry is much safer today than it was 30 or 40 years ago, mainly due to a more qualified workforce, the use of automated equipment, and a corporate culture more focused on occupational health and safety (OHS); however, the number and the severity of occupational injuries and diseases continue to make this industry one of the most hazardous. In the province of Quebec, the mining industry accounts for approximately 0.4% of paid workers but is the source of 4% of fatal work accidents. It is, therefore, important to continue the prevention efforts already underway in the mining industry.The difficult global economy, which has affected the mining industry in the last few years, is an opportunity to reaffirm that sound management of OHS can have a positive impact on companies’ productivity and profitability. Occupational injuries and diseases are costly for the companies concerned and for society as a whole. Reducing their occurrence makes it possible to reduce not only the size of workers’ compensation board contributions but also several other financial and human costs."

Jan 1, 2018

Whilst decisions to commit projects have traditionally been heavily influenced by hurdle rates for d.c.f. analysis, it is suggested that evaluation of competitors' costs may be a desirable additional tool.The MICAS system developed over the past four years is described. This computer system uses standard costs modified by District and Mine factors to allow estimation of individual mine costs. The data base contains more than 15,000 items of data and more than 6000 costs are calculated.Recent applications include use for competitive analysis, predictive analysis, statistical analysis, and comparative assessments with scopes ranging from a few mines to the whole Australian export industry. Some areas where care is necessary are outlined and potential further uses are discussed.

Jan 1, 1985

By Anderson Pereira

SORM 3plus (SORM = Superfast Optical Roughness Measurement) is a system enabling online measurement of roughness parameters during continuous strip processing. Increased requirements for new materials and more complex components call for ever increasing process safety. The roughness parameters are important quality features of uncoated and surface refined strips. The traditional method of measurement involves using a mechanical stylus based instrument. For this purpose the operator must stop the production line or samples are taken from the end of the coil and measurements are made offline in the lab. SORM 3plus, however, is a non-contact, online surface roughness measurement system that can be used for metallic and many non-metallic surfaces at strip speeds of up to 2400 m/min. The surface roughness data are stored in the system computer, displayed to the operator and if needed are fed into a higher-level network. The operator is alerted, if the limited values preset by him are exceeded or if any changes within the line will put at risk the production process. SORM 3plus calculates the roughness parameters as defined in the standards, such as the arithmetic average roughness (Ra) and the peak count (RPc).

Oct 8, 2019

By V. C. Lo

The major cost in comminution is energy consumption, which can be as high as 50 percent of the operating cost. Improvements in plant operations have resulted in up to a 15-percent reduction in energy usage (kwh/t). These improvements have been made through optimization of grinding efficiency and use of expert model-based control systems. Optimization involves the determination of the levels of the critical operating conditions that result in the most efficient breakage of ore in the mill. These optimal levels are identified through plant/laboratory testwork and computer simulation using advanced process models. Model-based expert control achieves the maximum performance from the grinding circuit by identifying the characteristics of the ore in the mill with an optimal on-line estimator. Using this information, the control system dynamically determines the operating point that will yield the optimal performance. Two industrial applications of grinding circuit optimization and model-based control are presented to demonstrate the power of this new technology.

Jan 1, 1995

By A. Anani

The goal of hot mix asphalt (HMA) design is optimal material blending to meet Superpave specifications. HMA cost minimization has being modeled as linear programing (LP) (Awuah-Offei et al 2011) and mixed integer LP problems (Brown et al, 2012) and solved with commercial software such as LINDO and CPLEX. Often these software, which are designed to solve general optimization problems, have licenses that cost thousands of dollars. The objective of this study is to develop a novel solution algorithm to the HMA optimization problem presented by Brown et al. (2012), which will negate the need for expensive commercial packages and is specific to this problem. This novel algorithm is based on the branch and bound algorithm for solving mixed integer problems. The algorithm is incorporated into a software package with an easy-to-use graphical user interface. The developed algorithm is validated using a real-life HMA problem. Using this solution algorithm will save companies thousands of dollars, otherwise used to purchase software licenses.

Feb 23, 2014

By Michael Drozd

The operation of an activated charcoal system has five separate unit operations. These unit operations have common points for CIP, CIL and CIS system, which vary widely in application. a. Absorption b. Desorption (Stripping) c. Acid Washing d. Reactivation e. Carbon Handling ( carbon transportation, sizing, de­watering, etc.) Cost optimization starts with the basic operating parameters (design philosophy) set down at the time of engineering design. This parameters undergo almost immediate change due to site specific ore requirements, throughput changes, operator requirements or reagent availability. Activated charcoal is sometimes viewed as simple, uncomplicated reagent that requires not optimization. To some extent, this statement is true, but under most circumstances, if the time necessary to optimize the use of activated charcoal is available, the effort is rewarded with significant savings. CPL-Carbon Link has embarked upon a program of supplying technical support with its activated charcoal. Several operation in the United States have under taken to have CPL-Carbon Link do an operational survey to determine if potential savings are possible. CPL-Carbon Link has offered to do these surveys for projects that are clients or simply would like to have CPL-Carbon Link review their operation. The information accumulated by CPL-Carbon Link is being used to attempt to fashion industry standards so that a common reference point came be establish for activated charcoal usage.

Jan 1, 2000

By Gavin A. Hunt

In order for mines to operate profitably throughout their life it is important to monitor and maximise ore recovery. A common problem facing many mines is the underestimation of clay type and its distribution in ore at the mine face, blast hole or in the ore stockpile. Too much clay entering the heap leach ore stream for example causes a dramatic reduction in heap leach efficacy and or increased leaching times. The end result is poor leaching performance and much reduced metal production. Poor clay identification and quantification is attributable to many factors, including costly and slow off-site mineral analysis techniques, such as XRD, XRF and petrology, the visual and subjective limitations of the core logging geologist and a lack of suitable low cost, high throughput mineral logging instruments. To get round these problems a new, non-contact, imaging spectrometer - the SpecCam - was developed by Spectra-Map Ltd, to allow high throughput identification and quantification of minerals from mineable material. Its novel imaging design can collect millions of data points (pixels) per day; each pixel contains spectral information that allows a wide variety of mineral types, including the smectite and illite clays, and phyllosilicates such as talc and kaolin, to be identified. Because all the ore can be imaged a much more reliable mineral log can be made. Hence, mapping changes in mineral composition - related to variations in phenocrysts, macrocrysts, veining or wall rock - is possible. Examples of SpecCam data from Goldfields Cerro Corona Porphyry stockpile and from Rio Tinto?s Argyle Diamond mine illustrate the mineral identification and quantification capabilities of the SpecCam. More importantly, for the first time very accurate % abundances for the different minerals can be obtained using an image-based modal count technique. The modular design of the camera, plus its extremely flexible high speed filter, mean that the SpecCam can be easily installed on different equipment, each one suited to different ore recovery problems. For example the SpecCam can be used on an automated portable logging frame to measure drill core, RC chips, hand samples or powder, or alternatively installed on a Geotek multi-sensor core logger for high-throughput, automated logging of drill or blast hole core using co-registered multi-sensor data. An exciting recent development has been the installation of the SpecCam on CommoDas ore sorting equipment, used around the world for 24 hour mill-feed monitoring and automatic ore sorting. Real-time ore sorting decisions can be made as material is monitored on a conveyor belt running at 3m s-1, from which the ore can be automatically sorted into high-grade, low-grade or waste streams for example. The three installation options for the SpecCam mean that most mineral analysis and automated core logging or ore monitoring needs can be met at the mine. For the first time rapid and automatic mineral identification and accurate quantification can be made. All of which allow the mine geologist or metallurgist to make important decisions about maximising the metal recovery process.

May 1, 2007

By Joseph A. Dos Santos

"The subject of this writing was first published in 1998 with the emphasis on the hardware cost comparison. Other costs, such as the required land area and spatial volume, were mentioned but not emphasized, as these were not deemed as important for new projects where the space was appropriated as required. During the last decade, these other costs have proven to be more than equal in importance. These costs are emphasized here through specific accounts of actual highangle conveyor installations that demonstrate the importance and the high-angle advantage An update on the progress in sandwich belt highangleconveyor technology is also provided.Origin and progress in sandwich belt conveyorsCover belts of the 1950s. Large volume, highangle conveying by “conveyors with cover belt, dates back to the early 1950s, when such systems were employed at the bucket wheel excavator boom conveyor in German lignite mines to increase the depth of cut without increasing the boom length. Various systems were developed, patented and built. These systems were not a lasting success for various reasons, which are noted by Rasper[1]. In his 1958 “Review of Cover Belt Systems,” Rasper summarizes the characteristics which are worth pursing and those that should be abandoned. The former are akin to good conveyor engineering. The sandwich belt conveyor model. The first sandwich belt conveyor model allowed calculation of the required hugging pressure to develop the bulk material’s internal friction and preclude material slideback. A modern, accurate version of the sandwich belt conveyor model is presented in Fig. 1. This model depicts accurately a derating of the material cross-section allowing an ample belt edge distance that can tolerate normal belt misalignment without material spillage. The calculations must thus recognize that only part of the hugging pressure is imparted onto the material with the remainder transferred belt edge to belt edge affecting a material seal. Mathematical development of the sandwich belt model is covered by Dos Santos and Frizzell in their 1983 article, “Evolution of Sandwich Belt High Angle Conveyors.”"

Sep 1, 2016