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By I. E. Teymenson, L. A. Bakhvalov

Irrational usage of mineral commodities leads to depletion of natural resources and various ecological violations in natural environment. Fulfilment of a number of measures and strategic decisions by given problems requires a correct forecast of trends of social-economic systems. For solving the task of long-term forecasting special procedures, considering Kondratyev’s big cycles of world conjuncture, have been embedded into algorithms of unknown parameters identification and recovering of factors of different countries mineral resources production and consumption models. In the paper the classification of long cycles types, existing forecasting algorithms on the basis of Kondratyev’s ‘long waves’ or ‘K-waves’ and the modified algorithm, developed by us, which allows to reduce time and financial expenses and to improve the forecast quality, are presented. Furthermore, the article includes several forecasts of mining branch corrected models factors, received by us, permitting complex prognosis of economic and social development of different scale and control level systems. In the paper workability of proposed forecasting algorithms on the base of ‘K-waves’ and adequacy of created models to researched processes are proved.

Jan 1, 2003

In this paper, geostatistical techniques are applied to forecast the annual copper price in the short and medium terms (from one to five years ahead). These techniques allow the incorporation of monthly and multivariate information in the analysis and provide more accurate results than traditional approaches, especially as far as the one-year forecast is concerned. A second advantage of geostatistics stems from its ability to assess the uncertainty associated with the unknown future prices, thanks to estimation variances or confidence intervals, depending on the technique used. Such an assessment has a crucial importance in decision-making, from both macroeconomic and microeconomic points of view

Sep 1, 2004

By A. Cabañas

"In this paper, geostatistical techniques are applied to forecast the annual copper price in the short and medium terms (from one to five years ahead). These techniques allow the incorporation of monthly and multivariate information in the analysis and provide more accurate results than traditional approaches, especially as far as the one-year forecast is concerned.A second advantage of geostatistics stems from its ability to assess the uncertainty associated with the unknown future prices, thanks to estimation variances or confidence intervals, depending on the technique used. Such an assessment has a crucial importance in decision-making, from both macroeconomic and microeconomic points of view. IntroductionThe copper price traded in the London Metal Exchange is a relevant parameter for defining macroeconomic policies of producing countries like Chile. It is also a key factor for the mining companies, since fluctuations in the sell price affect the expected financial flows. Due to the amount of money involved in decision-making, it is necessary to have accurate forecasts of the future copper prices and to quantify the uncertainty associated with such prices.This paper focuses on the annual copper price estimation in the short and medium terms, i.e., from one to five years into the future. Henceforth, the word “estimation” will be used as a synonym of “forecast,” according to the geostatistical jargon (Matheron, 1989).Two main approaches, based either on statistics or econometrics, are currently used to forecast commodity prices, but both of them are not very accurate when applied to copper. First, the main methods are briefly reviewed, then the geostatistical formalism will be presented. So far, the latter approach hardly has been used to estimate commodity prices, although it may reconcile both statistics and econometrics via (1) the use of a stochastic approach and (2) the handling of ancillary variables related to the copper market. Another advantage of geostatistical techniques is the ability not only to forecast the copper price, but also to measure the uncertainty associated with it."

Jan 1, 2004

By Jonathan S. Jackson, Bayne B. McMillan, W. Joseph Schlitt

Various dump leach models have been developed by Kennecott, and these are reviewed with an eye toward production forecasting. Some of the models have been bated on first principles, utilizing the chemistry and physics of dump leaching. While providing considerable insight into the leaching process, these have proved to be too cumbersome for use in estimating production. Other models have been based on a declining leach rate for a single block of waste. These permit good short-term projections of solution grades and production, but are inflexible with regard to changes in mining parameters because the trends are based only on historical data. Therefore, a simple and flexible computer model has been developed to aid in leach production forecasting and to provide a tool for assessing the impact of different mining plans on leaching. This program, LEACH, is based on annualized blocks of waste; input parameters are described and examples of its use are given.

Jan 1, 1980

By J. L. Hoover

The goal of the drill bit consumption study was to develop an equation(s) based on various components that affect bit drill wear and use the equation(s) to estimate the consumption of bits during production drilling. Drill bit data from various geographic locations were compiled and used to develop linear regression equations using the Microsoft Excel Software. Multiple drill bit consumption equations were developed and statistical analysis was used to verify the accuracy of those equations. The equations will allow mining companies to more accurately forecast drill bit consumption when evaluating new mine properties. This capability becomes increasingly beneficial to forecasting as the cost of consumables increases.

Jan 1, 2012

By J. L. Hoover, P. W. Conrad, J. Downey, S. Parrow, S. Rosenthal

The goal of the drill bit consumption study was to develop an equation(s) based on various components that affect drill bit wear and use that equation(s) to estimate the consumption of bits during production drilling. Drill bit data from various geographic locations were compiled and used to develop linear regression equations using the Microsoft Excel software package. Multiple drill bit consumption equations were developed and statistical analysis was used to verify the accuracy of those equations. The equations will allow mining companies to more accurately forecast drill bit consumption when evaluating new mine properties. This capability becomes increasingly beneficial to forecasting as the cost of consumables increases.

Jan 1, 2012

Forecasting, particularly when applied to meaningful issues, is known irreverently as 'futurology'. There is quite a range of opinion ext.ant in the world when mineral resources are looked at. The opinions range from the doomsday view that there will be acute shortages of all essential commodities, to the optimistic outlook that new 'discoveries will prevent any possibility of shortages. The environment is, as yet, only studied locally and quite parochially; surprisingly there is little integration when considering the spatial atmosphere, the seas in depth and the earth's crust.

Jan 1, 1981

By C. Ozgen Karacan, William P. Diamond

In This Chapter [Measuring the gas content of coal Predicting gas emissions based on geologic and coal reservoir property data Determining the gas storage capacity of coalbeds and other gas-bearing strata Methane drainage borehole monitoring to forecast the remaining gas-in-place and the influence on mine emissions Forecasting gas emissions during mining as a function of mining parameters and Gas emission prediction based on numerical simulation] This chapter provides guidelines for determining the gas content of coalbeds, estimating the gas-in-place, and predicting gas flow and emissions before and during coal mining operations. The techniques are discussed briefly in the following sections. However, detailed information on the techniques is provided in the cited references. INTRODUCTION Coalbed methane, if not properly controlled in the underground mine environment, is a safety concern due to the potential risk for an explosion. This is a particular problem during longwall mining, where the high rate and volume of coal extraction can result in the release of large amounts of methane from the mined coalbed and other adjacent gas-bearing strata. The variability and potential hazards of these sometimes unexpectedly high gas flows provide the impetus to develop methods to predict methane emissions into the underground workplace. A forecast of the volume of gas that might be released during coal mining is helpful for designing ventilation systems and for implementing optimum methane drainage strategies to help mitigate expected gas emission problems. A complete assessment of the need for methane drainage prior to mine development generally requires both an empirical and a theoretical approach. If there are active mines in the general area with similar geologic conditions and coal characteristics, a review of gas problems in those mines provides an initial insight into the level of gas emissions to be expected at a new location. In addition, relatively simple methods exist to determine the in situ gas content (volume of gas per unit weight of coal) of the coalbeds in a particular mining area, as well as the gas-in-place (volume of gas in the coalbed(s) within a defined geographic area).

Jan 6, 2006

By C. Özgen Karacan

Gob gas ventholes (GGV) are used to control methane inflows into a longwall operation by capturing it within the overlying fractured strata before it enters the work environment. Thus, it is important to understand the effects of various factors, such as drilling parameters, location of borehole, applied vacuum by exhausters and mining/panel parameters in order to be able to evaluate the performance of GGVs and to predict their effectiveness in controlling methane emissions. However, a practical model for this purpose currently does not exist. In this paper, we analyzed the total gas flow rates and methane percentages from 10 GGVs located on three adjacent panels operated in Pittsburgh coalbed in Southwestern Pennsylvania section of Northern Appalachian basin. The ventholes were drilled from different surface elevations and were located at varying distances from the start-up ends of the panels and from the tailgate entries. Exhauster pressures, casing diameters, location of longwall face and mining rates and production data were also recorded. These data were incorporated into a multilayer-perceptron (MLP) type artificial neural network (ANN) to model venthole production. The results showed that the two-hidden layer model predicted total production and the methane content of the GGVs with more than 90% accuracy. The ANN model was further used to conduct sensitivity analyses about the mean of the input variables to determine the effect of each input variable on the predicted production performance of GGVs.

Jan 1, 2009

By J. Cygankiewicz

Efficient prevention of mine fires is impossible without predicting the self heating processes in the given geological and mining conditions. The respective forecasting method is presented in this paper based on the following assumptions: - factor deciding on fire hazard in the underground workings is the process of heating of coal from the primary rock temperature to the critical temperature when the heating rate growth rapidly - another important factor is the fire incubation time defined as time needed to achieve the critical temperature. This time is determined by balance of heat and mass in the heated coal - contact of crushed coal with oxygen in air cause some exothermic processes as : physical and chemical sorption of oxygen , oxidation reaction and evaporation of humidity Heated coal transfers its thermal energy to the environment by conductivity to the rocks and by convection to the flowing gases. The heating is possible if thermal energy generated from coal is greater then the share transferred to the environment. The paper presents the laboratory method of measurement of heat generation in adiabatic conditions. Also the mathematical model with examples of computation enabling to forecast the self heating process of crushed coal is presented.

Jan 1, 2003

By P. M. Solozhenkin, O. I. Ibragimova, I. P. Solozhenkin

Molecular models of complexes of poorly studied bismuth, gold, and arsenic mineral clusters and reagents were created for use in collector activity forecasting using Chem Bio 3D and ChemOffice2005, with optimization by MM2. The density functional theory approach was used to determine HOMO, LUMO, SOMO, and total energies, atomic charges, and s, p, d- populations for various compounds. The structure-based virtual screening (SBVS) and docking technique was proposed to reduce the vast number of compounds to a more manageable number for selection of potential flotation candidates. The prognosis of collector activity evaluation (PCAE) strategy was proposed as a consistent approach to estimate the interaction between a collector and a mineral cluster as the difference between the total energy and sum of cluster energy and collector energy to search the analogue of butyl xanthate. The negative relationship between PCAE and flotability was shown. The combinations of dialkylamino sulfhydryl collectors can be considered as prospective reagents for gold-bearing sulfide ore flotation. These results were confirmed by experimental data in ore flotation. The increase in recovery of gold and bismuth with the aid of a combination of reagents has been established and additional cyanidation of tailings has been avoided.

Jan 1, 2016

By Nick D. Rose

Outline ?Background ?History of inverse-velocity for failure prediction ?Methodolog ?Case Histories ?Three case examples of predicted slopefailure to actual date of occurrence ?One case example of mitigated slope failure using inverse-velocity to forecast failure time and schedule remedial measures ?Conclusions

May 1, 2006

By John L. Edwards, Anthony T. Iannacchione

There has been a persistent need to forecast roof falls so that miner’s exposure to hazardous underground environments can be minimized. Several monitoring techniques have been developed and are used today with varying levels of acceptance in the mining industry. This paper examines the potential for monitoring microseismic emissions activity as a means of forecasting roof falls. The use of this activity to forecast roof falls has drawn only limited attention, resulting in a lack of published field performance data. This deficiency is being partially addressed by analyzing data obtained during longwall mining at Moonee Colliery in 1998. The Moonee data base contains a wealth of information concerning roof fall forecast parameters and the seismic alarm criteria used to develop these forecasts. Four seismic alarm criteria were developed and used by Moonee with varying degrees of success. Roof falls were forecasted 73% of the time with average forecast times of 54 minutes. Ninety percent of the predicted roof falls had a warning time, i.e., the time between warning and roof fall event, of greater than 1 minute. The fraction of forecasted roof falls decayed logarithmically as a function of warning time, until only 20% of events were predicted more than 100 minutes prior to roof falls. False alarms occurred in 50% of the warnings. Many of the false alarms were quickly followed by a cessation in mining which could have temporarily halted the on-going failure process. If mining had continued immediately after the false alarms, a roof fall may have occurred soon after. The microseismic activity collected from Moonee Colliery demonstrates that techniques to forecast roof rock instabilities in underground mines are possible.

By S. K. Oraee

Most management decisions at all levels of the organization are as directly or indirectly depends on the circumstance of future. With regard to predict the future events in the process of decision-making plays a main role, therefore, forecasting is very important for every organizations and institutions. There is a variety of methods to predict time series. In general, these techniques can be divided as following: statistical, artificial intelligence and analytical techniques. Two of the most common methods for time series prediction is autoregressive integrated moving average (ARIMA) and artificial neural network (ANN) methods, these methods are the subset of statistical and artificial intelligence techniques respectively. In this paper, a hybrid model of ARIMA and ANN models are employed to predict the number of fatal injuries in the USA underground coal mines. This research showed the result of hybrid model is better than split model.

Jan 1, 2011

By Steve Kral

Competition from foreign coal producers could displace as much as 9 Mt/a (10 million stpy) of US coal bound for power plants located near waterways. But, according to a Maryland-based coal consultant, it could be worse. Theoretically, about 52 Mt (57 million st) of domestic coal could be vulnerable to imports by 1990, said Forrest Hill, of Hill & Associates of Annapolis. Hill was speaking to about 150 coal industry executives and experts at the third annual Coal Marketing Strategies Conference in November. Most were at the Denver, CO conference to pick up tips on how to sell coal in an oversupplied market. Imports threaten domestic markets Of the 200 utilities studied by Hill and his staff, 119 are situated near major waterways, he said. However, most of those waterways are not equipped to handle coal from the shipping lanes. Good news for US coal producers. But don't breathe too easily. Foreign coal still poses a major threat to domestic markets, Hill continued. The strength of the US dollar is an obvious factor. But easy access to US utilities located on waterways combined with low rates for ocean vessels give foreign producers another edge. And foreign mines are typically low cost producers. For example, Hill said Colombia's huge Cerrejon mine can deliver coal to an Illinois power plant for $47.87/t ($43.39 per st). That compares to $52.85/t ($47.95 per st) from a Kentucky coal mine. Also, Colombian coal producers can generate a cash flow even if the coal sells for $27.50/t ($25 per st). The main competition US producers face from abroad, as Hill sees it, comes from Australia, Canada, Colombia, Poland, South Africa, and, perhaps, from Venezuela. Domestic producers, however, do have some things going for them. Most US coal buyers, Hill said, "are not wild about the idea of buying foreign coal." A 10% price advantage or pressure from public utility commissions would be needed to force some of them to buy foreign coal, he said. Some of the utilities contacted said they would not commit to more than one-third of their stockpiles to a foreign source. Another advantage for US producers is that they have room in their long-term contracts to cut prices and still maintain a profit, Hill said. Railroads, too, have high profit margins written into their rate structures. They are also aware of the import threat. Therefore, they may reduce their rates accordingly to keep their markets. Marketing's role The energy price shocks of 1972 and 1976 caused major adjustments in world economics. Coal was no exception. High oil prices caused many utilities to look at less expensive coal. As the market improved, coal prices began to respond, said R. Gale Daniel, of Anaconda Minerals Co. But clean air legislation and the strengthening dollar caused havoc in the coal markets, he said. The price of oil crashed, taking with it predictions of record coal use. The result is an oversupply of coal that has led to price cutting. Now, coal marketing must be recognized in its "true leadership role," Daniel said. Marketing people must know when to use spot sales to balance production objectives and maintain cost-effective-

Jan 1, 1986

The theme of this conference is æRediscover OtagoÆ. In order to ensure the development and exploitation of mineral discoveries in New Zealand, considerable capital will be required, particularly from overseas. This paper briefly reviews the Government's foreign investment policies and procedures and highlights some trends.

Jan 1, 1992

By Samuel Lasky

WITH the movement of American capital into foreign investment, a new field of specialization for the American mining engineer is gradually opening a field hitherto entered almost wholly by chance and without full appreciation of its possibilities. Our age has been fitly called the "Age of Specialization." The special application of one's knowledge and ability to a definite and restricted branch of .his profession is purely a modern condition. Any profession, or branch of a profession or, industry, in which the problems may be segregated into definite types, calls for specializa-tion. Modern industry demands efficiency and that, reduction and ultimate annihilation of waste. Effort and time wasted by workers' on a problem with which they are not familiar is as flagrant a waste of money -the final standard-as any waste of materials. One of the subdivisions of mining engineering which is beginning to be recognized is of engineers who are clearly conversant with the particular and peculiar problems obtaining under foreign operating conditions. The need is as yet obscured, however, by the domestic prosperity of our American mining industry. The opportunity here lies more with the American engineer than with other nationals. The foreign en-gineer now in that service is not there through a realiza-tion of the special opportunities that exist, but through necessity, whereas, with the American engineer, more especially ,the recent graduate or those who will soon graduate, this is a new field to be entered wholly by choice. As a matter of fact, many engineering students will find it necessary to seek foreign service if they wish to remain in mining. Although the scope of the domes-tic industry is tremendous and there are many positions open to the junior engineer, there are not enough for the great number of graduates turned out yearly from our, mining schools. Educators tell us that less than 40 per cent. of the students in engineering schools gradu-ate; and of these but a minority continue in engineering. Even this minority is too great for our domestic. In-dustry, and although the young engineer realizes that condition after a few years he rarely seeks foreign work. A. perusal of the directory of the American Institute of Mining Engineers indicates that, but about one-half of one per cent of the Junior Associates are in positions outside of North America. Granting that most of them are still in school, the figure is surpris-ingly small.

Jan 1, 1927

By Faruk Oksuz, Phillip L. Covell, Martin Doll

A series of difficult ground conditions causing high groundwater inflows and hazardous gas intrusion abruptly halted the construction of a 6.4-meter (21-foot) finished diameter and 1,890 meters (6,200 feet) long tunnel planned to serve as a 4-millioncubic meters (1-billion gallon) per day capacity river outfall for treated wastewater. Some 808-meters (2,650-feet) section of the constructed tunnel, TBM, and all other tunneling equipment were completely flooded with hydrogen sulfide laden artesian groundwater. The subsequent pumping and tunnel recovery efforts were unsuccessful and the tunnel was abandoned. In the end, the construction contract was terminated and options to redesign and reconstruct the project were re-evaluated to maximize the use of already constructed tunnel facilities such as the construction access and inter-mediate shafts and six outfall diffuser shafts in the river.

Jan 1, 2007

By N. A. Barcza

This publication records the proceedings of the Tenth International Ferroalloys Congress, INFACON X, and the third INFACON hosted in South Africa. The Proceedings of the previous two South African congresses in 1974 and 1992 serve, as this volume does, as a valuable record of the papers presented at these important events. This publication comes at a time in South Africa?s democratic development where the theme ?Transformation Through Technology? is very appropriate. The ferroalloy industry has played an increasingly significant role in transformation and black economic empowerment in South Africa, particularly through the advancement and sharing of technology. INFACON X plays an important role in this process, and the stakeholders and organisers of this Congress are thankful for the opportunity to hold this event at this time of transformation in our country. The world of ferroalloys, as well as that of the steel and stainless steel industries, has continued to change rapidly. Recent innovations, better use of resources, increased awareness of environmental issues and ongoing efforts to improve occupational health and safety are among the topics addressed at INFACON X and in these Proceedings. The theme of ?Transformation Through Technology? has been chosen to reflect the regional and global developments in the ferroalloy industry, and the crucial role that technology plays. The Proceedings of INFACON X, the first Congress in Southern Africa of the new millenium, represent a milestone in the technical developments in this major global industry. It contains almost eighty papers in twenty Sessions, from authors in twenty countries, covering raw materials, reductants, energy, electrodes, refractories, furnace design, post taphole services, modelling, simulation, control, sensors, fundamental issues and the applications of ferroalloys as related topics. The major ferroalloys, namely ferrochromium and ferromanganese, are covered extensively in many interesting papers. This comes as no surprise, since South Africa is the leading producer of ferrochromium and also plays a major role in the supply of manganese ore and alloys. Papers on ferronickel, silicon and ferrosilicon ensure that all the large-volume ferroalloys are addressed. These Proceedings of refereed papers of high quality will serve the ferroalloy industry for many years to come, as has been the case with previous INFACON events. For the first time in the history of INFACON, the Proceedings will be available both in bound and in a searchable electronic CD-ROM format. We appreciate the time and effort that the authors and referees have devoted to making this publication a really valuable document. Their contributions are recorded for posterity and reflect the advancements they and their colleagues have made to benefit the ferroalloy industry. Without these ongoing improvements, the industry would stagnate and not fulfil its role in the advancement of mankind. All papers included in these Proceedings were peer-reviewed by at least two referees. About 130 referees were sourced internationally to fulfill this function, and their valuable technical and editing inputs are gratefully acknowledged. Finally, I would like to thank the Technical Programme and Publication committees, led by Dr. Lloyd Nelson and Dr. Noël Machingawuta respectively. Without the tireless efforts of these individuals and their Committee members, the technical programme and these Proceedings would not have been the success they certainly are.

Jan 1, 2004

Pyrometallurgy has played a very important role in southern Africa for at least four centuries. It continues to do so, and recent years have seen many exciting developments in pyrometallurgical technology. The wonderfully diverse rich mineral deposits in this area of the world have provided some unique opportunities for industrial processes to be established. The ?Southern African Pyrometallurgy 2006? conference was set up to showcase southern African pyrometallurgical operations, and to provide a forum for the exchange of ideas between people working at various types of smelters. Papers have been obtained from a wide variety of pyrometallurgical plants in southern Africa. These descriptions of plant operations (as well as some history, and highlights of current work) will provide useful reference information for some time to come. Contributions are also included from universities, research organizations, and engineering companies, so that the full spectrum of pyrometallurgical activities can be covered. The plant descriptions will be published on a website, where they can be updated as and when required, with the eventual goal of having a description of every smelter in the region. The conference venue was selected to be the 'Cradle of Humankind' world heritage area, about 40 km from Johannesburg. Not only does this keep the conference within easy reach of the city and yet far enough out into the countryside to allow people to focus on the conference, it is also within easy reach of many pyrometallurgical plants. There is a particular significance to the choice of location, in that the Swartkrans area close to the Sterkfontein Caves is the site of the earliest evidence of the deliberate controlled use of fire by human beings (about 1.3 million years ago), and this is obviously a necessary precursor to pyrometallurgy. The area also lends itself to a very wide range of outdoor, social, and cultural activities to supplement the technical content of the programme. It is hoped that activities such as a hot air balloon safari and visits to the world-renowned Sterkfontein Caves and Wonder Cave will help to make the conference a memorable one for those able to attend. I trust that the ongoing value of the papers and presentations will make all the hard work of the many contributors most worthwhile.

Jan 1, 2006