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This is what I term ... the graveyard end of any Conference. It's almost over. Those of you remaining are either all talked out or past the information overload stage. And some of the sensible? ones have left for more exciting field trips, or gone back to their work-site where they earn their daily crust, or headed off South to another Conference of interest to the Energy sector that is being held currently in Christchurch. But that's OK. I have a thick skin! And neither am I particularly Politically Correct! I am not a miner: I am not involved in the mining industry in a hands on way at all. I am not even an academic. I am not even too sure why I am here ... apart from the fact that I agreed to come! At various times in my life I have been a D istrict Councillor, Chairman of a Regional Council and even an MP. I am a supporter of responsible mining.  All of what I have to say is my own point of view rather than that of either the Coal Producers' Federation or the mining industry. That is not to say that we are often in agreement, but I thought I would clear that point right at the outset. And some of what I will talk about will not strictly be to the topic - it's hardly mind-bending riveting stuff. Well, is it? But obviously because you are still here you have some interest in the topic.

Jan 1, 1997

By W. G. Freeman

It is unlikely, as In the past, improvement in truck efficiency and capacity can fully offset the effects of inflation, fuel costs/shortages and ever increasing haul distances. There-fore, investigations of haulage systems less sensitive to these problems are warranted. Thus, this U.S.B.M. contract research study on alternative continuous haulage systems was prepared. This study identifies the physical, economic and technological parameters in the application of continuous haulage systems with special attention to under pit slope conveyors and skip hoisting systems. The evaluation data was gathered from extensive literature searches. European/North American mine visits, and industry comments. The study concludes that continuous underground haulage is a viable method within the proper geometric configuration.

Jan 1, 1978

By Steven Putt

Seismic While Drilling (SWD) is a newly developed technology in the mining industry. Improving upon Measurement While Drilling (MWD) systems, SWD measures mechanical properties of the rock at incremental depths down a blast hole at a much higher resolution. SWD is also immune to common failures and inconsistencies of MWD such as operator and drill specific variation. Seismic While Drilling records the velocity and elastic modulus of the rock with centimeter accuracy in real-time. These properties measured while drilling blastholes are then used as a proxy for density which can be used for: • High resolution geologic modeling • 3D ore control • Drill and blast optimization • Drill to mill tracking One of the distinct challenges with SWD systems is the sheer volume of information acquired. With thousands of measurements per blasthole, the data can be overwhelming for even an experienced engineer. To overcome this complex challenge, the latest cloud computing and analytics models have been simplifying and organizing the data. These newer technologies can amplify an engineer’s capability by delivering actionable insights into their drilling and blasting workflows. The paper presents new results from Datacloud during recent Seismic While Drilling trials in iron ore, metallurgical coal, and hard rock mines around the world. The measurements are compared with wireline geophysical logs, core data, drill cuttings, and conventional measurement while drilling (MWD) systems to validate the technology and show how the data can be used.

By C. Sarkar

Increased competition in today’s global economy has put mineral industry under excessive pressure to effectively manage production assets to generate business wealth. Capital intensive industry (CII) organizations are seeking ways to manage skill resources, internal processes, and organizational networks with a view to reduce the cost of ownership of assets and increase efficiency of operations and service. The emerging concept of Enterprise Asset Management(EAM) is a collection of business processes that allow CII with right focus on return on investment on assets, to make right decisions on planning, acquisition, maintenance, operation, rehabilitation, and disposal of assets. Information technology (IT) can drive significant returns if the infrastructure covers seamlessly all business processes and all systems, like geographic information system, maintenance management, investment management, laboratory information management, and supervisory control and data acquisition system. The simple approach to IT in the past with disconnected silos of technology, information, and business processes cannot deliver the expected benefits under the modern business environment. Identification of business and application component is a prerequisite for the development of an asset management system that links effectively disciplined processes having characteristics of agility, speed, and integration. This paper discusses various issues and outlines the steps for developing an asset management roadmap in an organizsation. It also presents major business and application components of the system. Keywords: Enterprise asset management, Business architecture, Business component, Application component, Asset ownership, Asset operations, Information technology, Capital Intensive industry

Jan 1, 2003

By R. H. Grau, S. B. Robertson, F. Garcia, A. C. Smith, T. P. Mucho

Researchers working for the National Institute for Occupational Safety and Health (NIOSH) at the Pittsburgh Research Laboratory are developing ways to protect the health of miners. Part of that effort is devoted to improving the air quality in underground stone mines by developing ventilation techniques that can be used in these types of operations. The air quality in these large opening nonmetal mines can be significantly improved by using diesel particulate matter (DPM) controls along with sufficient ventilation quantities to remove contaminants. Practical methods of ventilating these underground stone mines can be accomplished by using mine layouts that course and separate ventilation air through the use of stoppings. The design, construction, and maintenance of effective stoppings in large openings have been a real challenge to mine operators. Several different types of stoppings have and can be used for this application. The choice of stopping design, material used, and construction techniques should be dependent upon a number of factors such as the intended life and effectiveness desired.

By N. Paas

Diesel powered equipment has been operated in underground coal fir mare than 50 years. According to the Mine Safety and Health Administration (MSHA), there are approximately 3,000 diesel units operating in underground coal mines in the United States. This number is expected to reach 5,000 diesel units in 250 coal mines by the year 2000. Also, there are approximately 5,000 diesel units operating in metal/nonmetal mines such as trine, potash and salt mines: and more than 3,000 diesel units operating in Canada. This increased popularity of diesel powered equipment over trolley wire, electric trailing cable or battery powered equipment is because of improved safety, greater mobility, higher productivity and increased power of diesel equipment. The operation if diesel powered equipment is not without challenges. Diesel engines generate exhaust emissions, in particular carbon monoxide, oxides of nitrogen, sulfur dioxide, unburned hydrocarbons, and diesel particulate matter that must be maintained at safe levels. The chief method to control ambient exposure has been dilution by ventilation. A new concept to ensure continued safe ambient emissions levels from diesel equipment in underground mines is the EMISSIONS MANAGEMENT PROGRAM™. The program encompasses all factors that will influence diesel emissions. By ESTABLISHING low tailpipe emissions through technology, such as clean engines, clean fuel selection, exhaust aftertreatment devices and filtration of the exhaust gases via the Dry System ™, this program ensures that the baseline emissions are at their lowest technically feasible concentrations. The DST Dry System™ exhaust conditioner reduces DPM by over 98%, as demonstrated through laboratory research at the West Virginia University. Carbon monoxide and hydrocarbon emissions and odor are similarly reduced. MAINTAINING these low emissions requires an expanded training program for operators and mechanics, onboard feed-back devices and a maintenance program with special focus on events and faults that can alter emissions. Finally, an on-board emissions sampling system allows the mechanic to VERIFY emissions levels and help diagnose engine faults. If the tailpipe emissions fall outside an established limit for a particular equipment, corrective actions will be initiated.

Feb 24, 1997

By Y Xiao, C Lei, C Shu, W Wang, K Wang, J Deng

To investigate the effect on coal spontaneous combustion with high geo-temperature, an experimental apparatus was developed to measure characteristic parameters of two kinds of coal samples at different temperatures: one was 40°C (G coal sample) and the other was a rising temperature from room temperature (C coal sample). Based on the relationship between CO concentration and the temperature variation, a calculation model of the apparent activation energy of coal was established. The results indicated that the oxygen consumption rate, the generation rate of CO and CO2, and heat release intensity of G coal sample were higher than C coal sample. This trend was more and more obvious as the temperature increased. Furthermore, the apparent activation energy of G coal sample was lower than C coal sample, especially at low temperature stage, which demonstrated that the more the oxidation and exothermic reaction of G coal sample was enhanced, the less energy was required to break the barrier of oxidation reaction. Under the same condition, the speed of oxidation reaction was faster for the coal in the high geo-temperature environment, which was more liable to spontaneous combustion.CITATION:Lei, C, Deng, J, Xiao, Y, Shu, C, Wang, K and Wang, W, 2017. The effect of high geo-temperature environment on spontaneous combustion – an experimental study, in Proceedings Australian Mine Vent Conference 2017, pp 137–142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By A. Deepatana

Bioleaching of nickel laterite ores is based on the use of heterotrophic fungi organisms and their metabolites (organic acids) to dissolve nickel and cobalt from oxide minerals to form metal-organic complexes. Metal recovery from this process using an aminophosphonic acid based chelating resin (Purolite S950) was investigated as a function of metal concentrations, complexing agent including citric, dL-malic and lactic acids. Batch adsorptions were conducted using synthetic leachate solutions of nickel and cobalt with concentrations from 15 to 2000 mg/L prepared in 0.01 and 0.1 M organic acids. Adsorption equilibrium data were interpreted using the Langmuir, Freundlich and Dubinin-Kagner-Radushkevich (DKR) models. The results showed that equilibrium adsorption data for nickel-organic complexes followed the Freundlich model and those for cobalt agreed with the Langmuir model. It was observed that the maximum adsorption capacities of nickel and cobalt were 3.26 and 10.48 mg/g resins respectively. These were achieved in metal complexes prepared from 0.01 M lactic acid. Metal elution was conducted using 2 M nitric acid. High metal recoveries were achieved from low metal concentrations but were found to decrease with increasing metal concentration. The results suggest that effective recovery of nickel and cobalt from low concentration of metals, such as those generated from bioleaching operations, can be achieved suitably using chelating resins.

Jan 1, 2006

By Gustavo E. Armijo

This job was done in Morristown, NJ, with mono fluid system jet grouting for the construction of a new bank building. After the demolition of the existing two story structures, an excavation in loose sandy fill materials was necessary in order to reach the new structure basement level. Due to this jet grouting was selected as a medium to provide both excavation support and permanent underpinning, minimizing the adjacent building settlements. These two adjacent buildings were partially underpinned with a "gravity wall" made with 2 and 3 rows of secant vertical and inclined jet grout columns. Besides the classical jet grouting control methods, during the jet grouting execution, all the drilling and grouting parameters were recorded by a proprietary system called "Slogger". Additionally, after the jet grouting execution, an innovative result control technique was used by means of the application of the same parameter recording system. Some of the production columns were re-drilled and a comparison was made between the obtained drilling parameters and those obtained for the same age test columns. Under the referred existing conditions and in comparison with the conventional underpinning techniques, this project demonstrated that jet grouting, with proper execution and result control, can be faster than them and can maintain the building structural stability and act, at the same time, as a retention system minimizing the existing building settlements.

Jan 1, 2002

By Ray Brandon

The recent introduction of polymer geogrids for ground control purposes in underground mines allows mine operators more flexibility in choosing improved products for several applications. This is evidenced most clearly in longwall recovery operations. Since November, 1994, many mine operators have chosen Fortrac geogrid assemblies for the purpose of securing longwall recovery areas prior to shield removal. Fortrac is a lightweight, strong, and flexible polyester geogrid available in many strengths. Utilizing the "diamond" seaming method, different strengths of Fortrac geogrids are easily fastened together so stronger geogrids may be placed in the most critical areas and lighter geogrids in less critical areas.

Jan 1, 1996

By Juan Lizana

El presente trabajo describe el proceso del sistema de gestión estratégica en la mina San Rafael, Puno. En este sentido, la empresa como parte introductoria de sus operaciones, ha propuesto la solución integral, donde la herramienta principal son los índices de gestión por unidades estratégicas de negocio y los índices de gestión por unidad operativa, los mismos que permitirán evaluar el desempeño de su organización frente a sus metas, objetivos y responsabilidades. En este sentido, el establecimiento de este sistema busca crear una cultura en la organización, a través del seguimiento de cada uno de los índices, permitiendo a la alta gerencia y a los demás niveles ejecutivos de la empresa hacer control de gestión, así como una reducción de los costos operativos en el Área de Mina y mejoras en los resultados de voladura.

Sep 12, 2005

By W. Kracht

Frothers are surfactants used in floatation to aid generation of small bubbles. Studying events at the moment of bubble creation is a challenge because of the short time frame. This presentation introduces a novel acoustic approach. The technique has the resolution capable of detecting events that occur within 1-2 ms. The transition from coalescence to non-coalescence is tracked as a function of surfactant concentration and gas rate through the capillary. Results are given for some common flotation frothers and n-alcohols (C4-C8). A stress model is used to give a qualitative explanation to the observed action of frothers on coalescence prevention. Results for salt (sodium chloride) are included for comparison).

Jan 1, 2009

By C Simpson, J Market

The process of sampling blasthole cones utilising personnel to manually shovel material into sample bags is a long-standing industry accepted process. However, this method has several drawbacks, including the safety issues around having personnel performing manual sampling in a harsh environment and the variability involved in getting a human to repeatedly get a ‘shovel full of dirt’, and make it always representative. Geophysical blasthole sampling, or utilising a Downhole Assaying Tool (DHAT) has been tested and has now begun implementation at many iron ore sites throughout the Pilbara region, Western Australia. This method uses a geophysical tool to capture data within blastholes, and together with a semi-autonomous logging platform to minimise risks around manual handling, delivers a multielement proxy-assay which can be utilised by the mine geology team to accurately domain the orebodies. Logistically, the combination of a specially designed tool and semi-autonomous truck are the way forward for a safer and more data-robust blasthole sampling practice. The method utilises a neutrongenerating geophysical tool and linked elemental spectroscopy sensor, which measures the response of the material surrounding an open hole. This delivers results at submetre intervals. These results are then utilised, similar to blasthole sample results, to map out areas within the blast pattern that are ‘ore’, ‘waste’, or ‘other suitable grade’. This paper outlines a project that has been in ‘proof of concept’ at selected Fortescue sites over the last few years with testing of these tools carried out on reverse circulation (RC), diamond drill and blastholes. The method is now being implemented at operational hematite mine sites. Fundamentally, the method adds more than enough value to justify its implementation. The aim is that these learnings will enable the greater industry to adapt, implement and improve their mining practices. Ultimately, the outcome will be greater value in mining for the industry by having a larger volume of good quality data to make reliable decisions on material movements, minimising ore-loss and dilution, and maximising the value of our current and future orebodies.

Nov 8, 2021

By Martin Pratt

This paper is an overview of deep foundation engineering in Hong Kong past, present and future. The enormity of the subject compared with the space available makes brevity inevitable. Issues of construction and design are covered and some examples of recent challenging projects are given. The content is aimed at those with an interest in foundations generally, but with limited knowledge of the Hong Kong scene. Reference is made to informative publications for further reading on specific topics.

Jan 1, 2000

By M. E. Coleman, G. Money

Pneumatic Conveying and Process Injection Technologies have been implemented in the metals markets for the last 40 years and have considerably improved the productivity and the performance of many processes. There have been many steps forward in handling technology and this paper seeks to consider those now offered by Clyde Materials Handling who as an established customer-driven solutions provider has turned its attention to supporting the Metals Market. Clyde seeks to utilise its knowledge, expertise and technologies to transform the production processes of its customers, who operate in the ferrous and non-ferrous metals industries.

Jan 1, 2008

By Michael G. Zabetakis

Vaporization of a solvent into an airstream at temperatures above the flash point of the solvent is hazardous if vapor is liberated at a rate that is sufficient to produce a flammable mixture. In may operations, the formation of such a mixture is prevented by rapid diluton of the vapors with air. The minimum air requirements for the dilution process are determined by the composition of the lower limit mixture at the temperature and pressure of interest. Because limits of flammability cannot always be calculated with sufficient accuracy for a proposed operation, they .rust often be determined experimentally. The present Bureau of Mines investigation was prompted by an application in which the lower limits of flammability of a number of solvent mixtures were required over a range of temperatures at atmospheric pressure. These limits were to be used along with available solvent-vaporization-rate data to establish minimum airflow rates needed to prevent the formation of flammable mixtures in an industrial process. Lower limits of flammability were determined for a number of mixtures containing methyl ethyl ketone, tetrahydrofuran, toluene, ethyl alcohol, and ethyl acetate in dry air-at atmospheric pressure and temperatures between 16° and 200° C. The experimental values were found to be in good agreement at with those predicted by Le Chatelier's law; variations with temperature were in fair agreement with those predicted by a modified Burgess-Wheeler law.

Jan 1, 1962

By Elmer W. Pehrson

OPINION seems widely divergent as to where we stand with respect to future mineral supply. From some quarters we hear that the United States is about to become a "have-not" nation and about to experience the evil consequences such a situation would entail. Others claim that we are still a treasure house of stored-up mineral wealth, the surface of which barely has been scratched. The data to be presented here support the conclusion that neither of these viewpoints is correct and that we are far from exhaustion of those mineral resources that are basic to our industrial economy. However, exhaustion is well advanced in a number of important subsidiary minerals so that we can no longer drift along with the easy-going philosophy that the earth will provide. The time has come when we must recognize the true situation and do something about it.

Jan 1, 1945

By Allan E. Martin, George Glocker, C. E. Wood

"INTRODUCTION As part of a comprehensive investigation of the mechanism of defurization of iron and steel by slags, the Blast Furnace Studies Section, Metallurgical Division, Bureau of Mines, in cooperation with the Institute of Technology, University of Minnesota, has made a study of the forms in which sulfur occurs in blast-furnace slag. This report presents data on the three sulfides most important in iron smelting, namely, ferrous sulfide, manganous sulfide, and calcium sulfide. The tendency of these sulfides to form colloids in the molten slag was determined by an examination of quenched samples with an ultramicroscope.Vogt/ conducted experiments on sulfide silicate melts and examined synthetic blast-furnace slags in a partly crystallized condition. His conclusions were that FeS, CaS, and MnS, or isomorphous compounds, such as (FexCay)S and (MnxCaa)S, were precipitated from the melt, depending on the composition of the slag. In all specimens sulfides were visible and were spherical.Coloration of glass by sulfur also provides indirect information on the nature of sulfur in blast-furnace slags./ There seems to be a general agreement at present among the workers in the field of colored glasses that ferrous sulfide is a strong color producer. Colors that have been attributed to this compound include yellow, orange, brown, blue, and black. Apparently the ferrous sulfide is considered to be dissolved in these glasses. There is no indication that any of them have been examined for a colloidal phase.Lorenz 7/ investigated a single manganese slag in the glassy state and observed a Tyndall beam in an ultramicroscope. His conclusion was that either a manganese compound had precipitated in a finely divided condition or that metallic manganese had volatilized and penetrated into the slag as a vapor and thus formed colloidal particles."

Feb 1, 1941

By J. L. Collins

"Une recherche debutee en 1987 tente de cerner divers éléments ayant un impact sur la productivite miniére, de facon à améliorer la planification des operations souterraines. II a été possible de recueillir jusqu'à trente variables dans sept opérations minières differentes du Nord-Ouest québécois. Cette présentation rend compte de quelques résultats préliminaires obtenus à l’une d'entre elle. Entre autres, elle montre comment une association entre une analyse de régression multiple et un logiciel d'optimisation (OPTIMUL) peut servir à une application particulière de la planification d'une opération minière du Québec. Plus spécifiquement, la présentation montre comment une quantité appropriée de ANFO et de TOVEX peut maximiser la quantilé de minerai cassé, minimiser les couts de sautage ou encore minimiser les coûts d'explosifs par tonne de roche cassée, en se basant sur une série de contraintes réalistes provenant de la mine.ABSTRACTA study, underway since 1987, tries to evaluate factors affecting mines' productivity. Information has been collected from seven underground mines in Quebec and this paper shows preliminary results from one. In particular, it shows how a combination of multiple regression analysis, mathematical programming and a set of realistic mine constraints can be used for a particular application of mine planning. More specifically, the paper shows a parallel between maximizing production of tons of broken are, minimizing explosives costs or minimizing the costs of explosives per ton of broken are by an appropriate selection of ANFO and TOVEX quantity of explosives. Finally, the paper shows that minimizing the costs of explosives per ton of broken are is the best alternative to follow providing a special optimization program can be set up."

Jan 1, 1990

This paper evaluates the effect of longwall mining on a cluster of unconventional shale gas wells located in a district barrier pillar between a current longwall panel and the future panel north of the barrier pillar. A cluster of 19 unconventional shale gas wells have been drilled and 5 additional gas wells have been proposed in the barrier pillar. The closest gas well is 25.6 m (84 ft) to the current panel tailgate and 26.2 m (86 ft) to the tailgate of the future panel north of the barrier pillar. The rib-to-rib width of the barrier pillar is 57.9 m (190 ft). The distance between the two gas wells across the barrier pillar is 6.1 m (20 ft). The pillars in the current tailgate are on 22.9-m (75-ft) and 32.0-m (105-ft) centers, and the pillars in the tailgate of the panel north of the barrier will be on 22.9-m (75- ft) and 36.6-m (120-ft) centers. The two longwall panels adjacent to the barrier pillar are 475.5-m (1,560-ft) wide. The overburden depth at the shale gas well site is 321.6 m (1,055 ft). The wells have been installed in the barrier pillar, and the current district panel and subsequently the panel north of the barrier will be developed and retreated in the near future. The average min

Jan 7, 2020