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By B. Cavender

Mining managers trying to rapidly reduce production costs tend to implement a traditional set of topdown managerial practices: reductions in production volume, employee layoffs, renegotiation of supplier contracts, cancellation of employee training, restrictions on travel, reductions in office supplies, and so forth. While these practices do reduce costs, the benefits are often limited in both magnitude and duration, and the workforce is usually left demoralized. Successful cost-cutters take a different approach. They make the continuous reduction of costs a priority for all members of the organization, whether managers or workers. The culture of these firms emphasizes the commitment, voluntarily given, of individuals and work groups to this goal. Cost-cutting practices often reject all of the traditional methods mentioned above, but are far more numerous, innovative and successful. This culture of cost reduction is the result of a set of leadership competencies that establish direction for the organization, align the organization's various constituencies with this direction, and motivate and inspire the organization. Cost reduction then becomes a routine task rather than a heroic achievement.

Jan 1, 2002

By Tony Walsh

Australian Stock Exchange Limited (ASX) -ASX is ranked 9th in the Morgan Stanley Capital International (MSCI) Index – only 2.02% of that Index. -1520 companies – 400+ mining & mining exploration. -Over 50% of Australians own shares in ASX listed co.s -Disclosure standards play a vital part in providing investors with confidence, thereby building depth and liquidity in the market.

Jan 1, 2003

By Beverly Cramp

In 1995, mining engineer Alain Gachet thought about using Earth-observation satellite imagery to search for precious minerals. The latest radar Earth-observation satellite, Canada’s RADARSAT-1, had just been successfully launched at the time, creating new opportunities for commercial applications. Gachet was working in Congo Brazzaville as an oil executive and general secretary of Elf Congo for the French national oil company Elf Aquitaine. He understood that the RADARSAT-1 launch promised new and cost-effective sources of data for mineral and oil exploration. “It was early 1996 before I ordered my firstRADARSAT-1 satellite images,” said Gachet. “I was first struck by the quantity of information delivered by the radar images. Linear structures and faults were clearly defined and subtle topographic features were tremendously enhanced,” he said. “It was ‘tree top geology,’ but this kind of information appeared to be key for finding new gold seams.”

Jan 1, 2003

By Randal J. Barnes

In, any open pit mine the ability to make accurate production estimations for the shovel-truck system is an important asset. This is true in an operating mine wishing to estimate production under a set of system modifications (i.e. more trucks, fewer loaders, change in roads, etc.), as well as in the pre- mining planning stages of a property. Many different methods have been proposed for solving this problem; some of the methods rely heavily on "rules of thumb" while others are highly mathematical and require access to a high speed digital computer. Analysis of shovel-truck systems with the use of simulation models is a widely accepted technique within the industry. Through the use of such models it is possible to account for much of the inherent variability of the system and thus produce meaningful results. However, simulation studies are expensive. Formulation and setup of the actual simulation model requires a significant commitment of time and energy. In addition, the cost of the necessary computer runs is often of considerable magnitude.

Jan 1, 1979

By Donald E. Dickie

At Sifto Canada's Goderich salt mine near Goderich, Ontario, the stress control method of mining was introduced to overcome increasing roof failure problems. After successful testing, the conventional room-and-pillar mining method was converted entirely to the stress control method. This conversion has successfully stabilized the ground, increasing the extracton ratio from 38% to 50%. At the same time, it reduced the ground control and rehabilitation cost by more than 80%. The success of the conversion is due to the quantitative technique of mine analysis that was developed to ensure that the conversion was safe and reliable. A finite element model of the ground was constructed to predict and validate the safety of the stress controlled mine opening. A system of in situ stress-property measurement instruments was developed to obtain input data for the computer model as well as to evaluate its output quantitatively with regard to time and location. History of roof problems Severe roof safety problems have been encountered at Goderich Mine since it opened in 1959. These problems continued into the 1980s. Following excavation, the roof strata started to deteriorate by slabbing. Even after roof rehabilitation, deterioration continued to progressively higher roof elevations, requiring repeated rehabilitation. The operational impact of these roof failures was severe, ranging from a considerable safety hazard to major production interruptions.

Jan 1, 1993

By Carlos A. Jaramillo, Seng Hing Ngu

"The Murum Hydroelectric Project is a 944-MW development consisting of a 145 meter high RCC dam, two 2660 meter long, 9 meter excavated diameter upper pressure tunnels, surge shafts, two 950 meter long 7 even meter OD penstock tunnels and a surface powerhouse. The project is located in the eastern section of the State of Sarawak, Malaysia, about 200 kilometer from Bintulu, in the Rajang Fold-Thrust Belt, an Upper Cretaceous to Upper Eocene fold and thrust belt that extends under most of Sarawak. The Belaga Formation consists of a thick sequence of deep marine sediments currently appearing as steeply dipping strata of thin to thick bedded, fine to medium grained sandstone interbedded with argillaceous rocks, resulting on a “Flysch” type geologic environment. The project pressure tunnels were excavated perpendicularly to these strata resulting on frequent change on rock conditions and behavior, and required rock support. This paper describes the characterization of the rock mass, design of rock support, and incidents during construction. Particularly interesting were convergence issues in Tunnel 1 resulting from Tunnel 2 excavation. INTRODUCTION The Murum Hydroelectric Project is located in the eastern section of the State of Sarawak, Malaysia, about 200 kilometers from Bintulu, and upstream of the Bakun Hydroelectric Project. The project consists of a 145 meter high RCC dam, a 50 meter high intake tower, two nine meter OD and 2660 meter long upper pressure tunnels, two nine meter OD and 175 meter long vertical shafts, two 25 meter diameter and 80 meter deep surge tanks, two seven meter OD and 950 meter long penstock tunnels and four seven meter OD and 50 meter long branch tunnels, two 8 meter diameter to 3.4 meter diameter and 1400 meter long penstocks installed within the shafts, penstock tunnels and branch tunnels ending in a powerhouse with 944 MW installed capacity. LAYOUT OF THE WATERWAY TUNNELS The two waterways tunnels are basically parallel as shown in Figure 1, with each tunnel supplying water to two units in the powerhouse. The tunnels start separated 25 meters center to center, but 250 meter from the intake the separation increases to 35 meters. The tunnels are lined with reinforced concrete until they reach the surge shafts and steel lined from there to the powerhouse. The tunnel profile is shown in Figure 2."

Jan 1, 2016

By G. L. Barthauer

It is a distinct privilege to have the opportunity of addressing this group today. Although I, myself, am not a mining engineer, I have always had profound admiration and respect for those of you who each day live and work according to the tenets of Murphy's Law. Murphy, as some of you may know, was an Irish philosopher whose sole contribution to his field was the observation, "In the mining industry, if anything can possibly go wrong, it will!" You have heard this afternoon a variety of papers, touching on or describing in some detail imminent problems which presently face the coal industry. Many of these problems show no signs of diminishing. Actually, there is good reason to believe that they will intensify as governing bodies pass additional enabling legislation and regulatory agencies adopt more stringent "Rules and Regulations". In many cases, these groups are seemingly oblivious or indifferent to either cost factors or technical problems involved in achieving the desired goals.

Jan 1, 1967

By Ahmed M. Yousif, Walid M. Abdellah, Galal M. Abdel Wahab, Amal E. Mubark

The present work is concerned with selective dissolution of niobium from Gabal El Faliq concentrate sample by using fluoridefree process. The chemical analysis of concentrate sample revealed the presence of high amount of ZrO2, Nb2O5, Re2O3, and HfO2 assaying 33.6, 1.99, 4.8, and 1.2%w/w respectively. Several economic minerals including zircon, samarskite, fergusonite, and xenotimewere recorded in the studied sample. About 98%of Nb content was selectively dissolved at the optimumconditions of 1:2 concentrate sample: KOH weight ratio, 2.5 h fusion time, and fusion temperature of 550 °C. Organic solvent extraction process using Aliquat 336S in xylene was effectively used for preparing pure Nb2O5 (98.95%).

Oct 22, 2019

By Ronald C. Severson

Crystals of native gold occur in placer-type deposits. Gold, as a pure metal, is the most malleable metal known; therefore, delicate gold crystal forms should not survive mechanical transport and concentration processes involved in placer formation. To test the hypothesis that the crystalline gold is currently forming in place, two active gold-placer operations and an unmineralized background area in Alaska were examined. At these sites, rock outcrops, soil profiles, and native vegetation were sampled. At one sampling site, the soil was panned and yielded crystalline gold, as well as the more common rounded nuggets. The plants and soils were analyzed for their major, minor, and trace-element contents, especially gold. Two procedures, one a simple demineralized water leach and the other a partial digestion with acetic acid and hydrogen peroxide, were also used to extract gold and various anions from soils. The water-extractable gold ranged from <0.02 to 15.0 ppb Au in the extracting solution. This represents as much as a 104 enrichment in gold over average river water. This extractable gold is probably available to the native vegetation. Gold concentrations in the unashed dry plants from the two placer sites ranged between 0.4 and 106 ppb compared to a background range of <1 to <4 ppb Au. The presence of dissolved organic matter in the soils is thought to be responsible for the dissolution, transportation, and precipitation of gold in these placer soils, and this process is presently active in these soil profiles.

Jan 1, 2013

By J. R. Nawrot

Reclamation of potentially acid producing coal processing waste requires a 4-foot cover, and/or treatment to allow vegetation establishment. If not planned properly, soil covering alone does not prevent refuse acidification or formation of acid seeps. Adequate neutralization enhancement prior to soil covering can maintain an alkaline environment in the soil refuse interface and prevent acidification. Direct vegetation establishment using only limestone amendment (without soil cover) can successfully reclaim aged and weathered fine (Blurry) and coarse (gob) refuse if adequate neutralization treatment is provided for the oxidized surface zone. Acid seeps, representing an "after-the-fact" verification of an imbalance of acid-base equilibrium may also be corrected using upslope alkaline recharge techniques. Concentrated alkaline recharge pools have been constructed above previously soil covered acid gob at the Peabody Will Scarlet Mine to abate acid seeps. Preliminary monitoring results (1989-1992) from a concentrated alkaline recharge pool demonstration project in the Pit 4 area of the Will Scarlet Mine have documented a 50 to 80 percent reduction in acidity in the principal recharge pool groundwater zone. A 22% reduction in acidity has occurred in the primary seeps located downslope from the alkaline recharge pools. The initial improvements in water quality are seen as a positive indication that groundwater acidity will decrease further and amelioration of the acid seep will continue.

Jan 1, 1993

By Kot F. Unrug

When reading different studies discussing trends in coal mining, it appears that a substantial expansion of output by the year 2000 is predicted, even in the most pessimistic forecasts. Depletion of shallow, easy-to-mine deposits is only a matter of time, and the future average mining depth will increase. The proportion of slope to shaft mines operated during the next decades will change in favor of the shaft mines. Since an increasing amount of shafts in new nine developments seems to be inevitable, it appears appropriate to focus more attention on shaft design criteria. Some valuable papers have recently been published (1) that emphasize geotechnical aspects of shaft design. In the discussion that follows some other aspects of design criteria will be evaluated.

Jan 1, 1984

By M. T. Long

The Crestmore Limestone Mine of Riverside Cement Company in Riverside, California is situated within 1.6 km of the Santa Ana River. It is an alluvium covered deposit with a massive quartz manzonite intrustion separating the upper and lower limestone beds which dip from 30° to 50°. The highly fractured upper bed contacting the Santa Ana alluvium contains many unique water inflow problems which vary, from multiple high pressure 19 liters per minute inflows up to 3,000 liters per minute to 11,000 liters per minute inflows-contacted by development mining in April 1983. A case history of the successful grouting of these inflows and the continual grouting procedures in advance of present mining with empirical&apos; results are discussed.

Jan 1, 1984

By John Davis Morgan

The uncertain world conditions of the present time require that the United States be prepared to meet: a. all-out nuclear war with attack on the United States b. limited wars (anything smaller than (a.) c. political, economic, and/or psychological warfare. Our present position as a major world power derives in large measure from our free institutions and our great industrial productivity, and our productivity in turn depends on an ever-continuing flow of raw materials from the earth - metals, minerals, fuels, and agricultural products. The United States, with only about 6% of the world&apos;s population, uses from one-third to two-thirds of the world&apos;s annual supplies of &apos;most metals and minerals. The United States strategic materials stockpiling program is designed to enhance our national security posture: as stated in the preamble of the Stock Piling Act, to decrease and prevent wherever possible a dangerous and costly dependence of the United States upon foreign nations for supplies of strategic and critical materials in times of national emergency. In times past, the Good Lord himself has ordered some stockpiling. The Book of Genesis in the Bible tells how Pharaoh of Egypt was directed to set aside one-fifth of the produce of the land in each of the seven good years to meet the needs of the seven bad years that were to follow: this would be a stockpile of about two years? normal use. Our cultural heritage often reminds us of the wisdom of stockpiling, as in the case of the stories about the provident squirrels that gather their nuts in an orderly manner in the f all to prepare for the winter&apos;s cold. And the old proverb about a bird in the hand being worth two in the bush points out clearly the value of something that is directly at hand.

Jan 1, 1960

By Xiang He, Xinzhong Wang, Ning Li, Bao Cao, Hongyang Bai, Zhigang Du

Revealing the periodic fracture pattern of the main roof and the key influencing factors of the support resistance is crucial for strata control and support selection of the shallow buried working face with large mining height. Based on the cantilever beam theory, an improved step rock beam model, and the measured strata pressure data of the 12,401 working face in Shangwan Mine, the mine pressure behavior law of the shallow buried with a large mining height working face was analyzed. The results show that both ratio of maximum principal stress to load (σ1/q) and ratio of maximum shear stress to load (τmax/q) inside the main roof increase with increasing periodic advancing distance, while the ratio of maximum shear stress to maximum principal stress (K) is the opposite, indicating that the increase rate of σ1/q is higher than that of τmax/q. K is less than 1 when the periodic advancing distance exceeds 8 m, indicating that the periodic fracture of the main roof will be dominated by tensile failure. Support resistance increases with increasing immediate roof thickness, main roof thickness, periodic fracture step distance of the main roof, and mining height, and decreases nonlinearly with increasing friction coefficient of periodic fracture rock block hinge surface. The main roof thickness, the periodic fracture distance of main roof, and the friction coefficient of the hinge surface of the periodic fracture rock block are the key factors influencing the support resistance. The advance breaking of the main roof and increasing the friction coefficient of the hinged surface of the main roof can reduce the support resistance of the working face. The support resistance of the 12,401 working face in Shangwan Mine presents an arch distribution characteristic. The average periodic weighting step interval, average support resistance, and dynamic load coefficient are 15.6 m, 17,552 kN, and 1.3, respectively. Finally, the rationality and validity of the model are verified by comparing the measured and theoretical values of the support resistance in the 12,401 working face of Shangwan Mine and other shallow coal seams with large mining height.

Apr 22, 2024

By K. C. Carriere

INTRODUCTION The purpose of this paper is to introduce the reader to basic control strategies for solid/liquid separation in mineral processing and to indicate some of the implementation difficulties to be encountered, without becoming overly involved in details of process, equipment or software. It is assumed that the reader has some familiarity with control systems and with dewatering processes, since exploration of these topics would require considerably more length. The paper is organized into three parts: first a general discussion on the need for control of dewatering processes and of the general criteria involved, next a more detailed elaboration on control strategies for the various unit operations, and finally a case study showing a specific approach towards such a project. Motivation & Objectives The justification for implementing any control system in an industrial plant is to improve operations and thereby to increase profitability. Without this motivation, the system will likely be perceived as unnecessary and will decline into disuse, an expensive and troublesome monument to someone&apos;s ill-conceived ideas. However, when a control strategy is correctly conceived, implemented and integrated into operations, it can provide significant advantages in operating ease and efficiency, and a handsome return on investment. In general terms, the objectives in establishing a control system are: • stabilization of process disturbances maintenance of product quality • maximization of throughput • dearer definition of process • protection of personnel and equipment A successful control strategy must address at least some of the above criteria. However, the most important requirement is a commitment on the part of plant personnel and management to start up, operate and maintain the system, and to upgrade it to reflect current process status and operational philosophy. Process Applications In this paper, control strategies will be explored for the most common methods of dewatering of mineral pulps. These unit operations include: drying, centrifuging, filtering and sedimentation. While the first three are important, they do not tend to be as complex as sedimentation, and thus will not be as exhaustively treated. Sedimentation is very widely applied, not

Jan 1, 1986

This paper reports on the behavior of mercury and its compounds during the thiosulfate leaching and recovery of gold. Thiosulfate solutions are shown to dissolve Hg0 and Hg2Cl2 to a similar extent as cyanide, but the leaching of HgS is significantly slower in thiosulfate solutions compared to cyanide. Hence, the use of thiosulfate may be an option for treating ores containing high levels of cinnabar, especially since the legislation concerning the discharge or sale of mercury is becoming more restrictive. The deportment of mercury during gold thiosulfate loading and recovery using a strongly basic anion-exchange resin was also studied. Although the mercury thiosulfate complex loads on the resin, the adsorption is weaker than for gold, with an equilibrium constant between gold and mercury of 51. Resin loaded with gold, mercury and copper was pre-eluted with thiosulfate (to remove copper) and eluted with a chloride and sulfite eluant. The majority of the mercury is eluted by the eluant and, hence, its deportment closely follows gold and the eluate would need to be treated to remove either mercury dur-ing or prior to gold electrowinning.

Jan 1, 2010

By Richard W. Amerman

The final cost and quality of a project employing equipment, labor, and materials is dependent upon the expediency and extent to which each of these parameters are used. An ideal solution then, would be one in which three solvable equations were given for each particular situation. The equipment, labor, and materials could then be solved for, and the perfect job would result. In reality, however, the ideal and most economical solution is seldom attainable by solving three given equations. Therefore, knowledge, experience, and sometimes guesswork must be relied upon when correlating equipment, labor, and materials. Drilling and blasting, in particular, is one operation which normally involves more uncertainty than other operations. It is also an operation in which the outcome is extremely critical for two reasons. First, the cost of the operation that follows drilling and blasting is dependent upon how well the material is fragmented. Second, once the drilling and blasting has taken place, it is impossible to return to the area, without considerable expense, and correct any mistakes that might have been made. Therefore, what is desired is a method by which drilling and blasting operations can be performed yielding optimum results at the lowest cost; this can best be accomplished by having the relationships between equipment, labor, and materials prior to their use. For obtaining best results, the selection of these three relationships must be based on knowledge, experience, and as little guesswork and uncertainty as possible.

Jan 1, 1969

By Kang-Hyun Lee, In-Mo Lee, Byung-Kyu Kim, Parkm Jinho, Seoung-Won Lee

"In this study, the TBM Resistivity Prediction (TRP) system is developed for predicting the location, thickness, permittivity ratio and electrical conductivity of anomalous zones ahead of tunnel face using the measured resistivity of the ground. The applicability of the developed system was verified by performing field tests at a construction site in which an EPB-shield TBM is used for tunnelling work. In the first field test, it was found that the rock around the tunnel face had the same resistivity and permittivity with the rock ahead of the tunnel face indicating no anomaly ahead of the tunnel face. In the second test, a stronger zone 5-m thick was predicted ahead of the tunnel face based on lower permittivity than that of the rock around the tunnel face. The ground condition assessed by the newly developed TRP system matched well with that either predicted from geophysical exploration or directly obtained from drilling boreholes or from daily observed muck conditions. INTRODUCTION During tunneling work, the emergence of unpredicted zones of relatively weaker or stronger ground can lead to delays in construction work or an increase of construction cost. Predicting anomalous zones ahead of tunnel face in advance can thus prevent time and economic loss. For these reasons, various methods to predict the ground condition ahead of the tunnel face have been studied and developed. Prediction methods using various kinds of equipment include tunnel seismic prediction, ground penetrating radar, electromagnetic surveys based on electronic antennas, and electrical resistivity surveys conducted by analyzing electric currents in the ground ahead of the tunnel face (Ryu et al. 2008). However, most of the prediction methods are only applicable to conventional tunneling job sites, which feature free access to the tunnel face. In mechanized tunneling projects, accessibility to the tunnel face is very limited because the tunnel face is occupied by the TBM."

Jan 1, 2016

By PDF

The adsorption of ethoxylated sulfonates and nonionics of the same ethoxylation number?on a low-ash coal has been studied. The surfactant adsorption has been investigated as a function of concentration, pH, temperature and ionic strength for three homologues. Zeta potential of coal particles and surface tension of supernatants has been concurrently determined to eludicate the orientation of sudactant molecules on the coal surface as well as the mechanism of adsorption process. The adsorption data are utilized to calculate thermodynamic parameters such as the free energy of adsorption and isoteric heats of adsorption.

Jan 1, 1988

By Paul Culvenor, Brad Gyngell

Ensuring effective management of contractual processes is essential for maintaining profitability and operational efficiency in mining. However, due to limited capacity and resources, sites often struggle to manage these processes effectively, leading to oversights and financial losses. Recent advancements in Artificial Intelligence (AI) offer promising solutions to these challenges. Large Language Models (LLMs), like those powering ChatGPT, now enable machines to understand unstructured data like contracts. These can therefore be applied to address these challenges by taking some of the heavy lifting off of humans. In this paper, we analyze a real-world case study of the application of LLM tools for preventing a $400k contractual issue on an underground gold mine in Western Australia. We provide a gap analysis of the failure modes in existing processes that led to the issue. We then describe the application of LLM tools to flag it early and facilitate a collaborative solution between the operator and the supplier. This includes a comparative analysis of base case vs LLM case to evaluate the impact on project cost and time. Finally, we discuss how the integration of AI can foster improved relationships between clients and contractors across a broad range of potential contractual applications, allowing the time required for collaborative and proactive problem solving.

Feb 1, 2025