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By D. G. Chedgy

This article presents a novel design, called the Climax High Capacity Processor (HCP), for pre-combustion cleaning of coal. This design is particularly suitable for the plant capacities of 400 -660 TPH. The HCP is different from the conventional designs with an equivalent throughput in three major aspects: 1) the use of one large capacity HM cyclone to separate coarse and intermediate raw coal in a single circuit; 2) the elimination of the conventional secondary magnetics recovery system by use of the high efficiency Climax magnetic separators; 3) the use of "single line" piping with a minimum requirement of ancillary devices. In comparison with conventional designs with similar capacity, the HCP plant costs much less in capital investment, operation and maintenance.

Jan 1, 1997

By J. E. McMenamin, R. B. Hall

"With the emphasis in the past decade on larger and more efficient equipment for open-pit operations, the Normandie mine of the Asbestos Corporation has followed the trend, switching from the smaller type of percussion drills to down-the-hole rigs. One 5 Y2 -in. percussion drill is still in use, but is limited to a ""smooth blasting"" role or to the control of the slope on final benches.In keeping with the times, an attempt was made to eliminate, as much as possible, the use of high explosives and to maximize the percentage of ammonium nitrate -fuel oil mixture. As the concentration of ground water increased with increased mining depths, small pumps were initially employed for the dewatering of boreholes. This proved unsuccessful, and a hole-blowing rig was built and a conversion to plastic liners made. The acquisition of a bulk-mix AN-FO truck has permitted the changeover from an AN premix to an ammonium nitrate prill -fuel oil combination at the borehole."

Jan 1, 1966

By V. M. Mankov, O. V. Zamyatin

"Fine free gold at a size of minus 250-100 µm can be effectively recovered from mineral materials (buried clay placers, saprolites, gold-bearing aggregates, technogenic sands etc.), or MM, using some developed and implemented in practice cost-effective basic technological schemes of MM processing at every stage: exploration, main concentration processes, upgrading of gravity concentrates etc. Such technologies are based on mineral materials composition, different content of fine gold mass fractions, and include improved two-stage sluicing technology, jigging technology, advanced technology and integrated technology. The main operation principle of the given technologies is gravity concentration. They provide recovery of fine gold of any size from MM, including gold finer than 100 µm, using concentration systems and plants with a capacity of 1-2 and up to 100-200 m3 per hour. Selection of a cost-effective technology depends on its technical and economic viability regarding to mineral material composition, optimum performance and concentration rate. The developed technologies of mineral materials concentration establish a balance between technological, technical and economic factors, and ensure profitable development of deposits containing free gold and characterized by a complex composition of concentrating material. Free gold recovery with these systems increases by 2.0-2.5 times for gold particles at a size of minus 250+100 µm and 10-30 times for gold particles of minus 100 µm, compared to conventional sluicing systems. The Irgiredmet Institute has developed and supplies primary concentrate washing machines for upgrading gravity concentrates of up to 100 mm in size, with a capacity of 1.0-5.0 m3/h, fitted with various production equipment including pyro- and hydrometallurgical systems. Additionally, the Irgiredmet Institute develops and manufactures systems of mechanized processing of geological and technological samples (UOMP; registered design certificate No.27505, Russia) designed for complete recovery of free gold in the process of geological samples handling and decreasing of a human factor influence. A system includes a package of technologically associated disintegration, classification and concentration equipment with some “know-how” elements that provide effective recovery of fine gold at the exploration stage. A number of Irgiredmet’s patented technologies and systems (patents of the Russian Federation) have no equivalents in the field of mineral processing and provide designing of technologically practical and cost-effective flowsheets that offer higher recovery of gold of different sizes (fine gold), at every stage of processing of mineral materials including basic concentration processes, upgrading and exploration etc."

Jan 1, 2018

By T. P. Meloy

Oily and particulate befouled waste water discharges are a common industrial problem. Removing these water bourn emulsions from process discharges become increasingly important for both recycled and discharge water streams. Low cost, efficient and easily maintained systems are important. This paper evaluates design factor of such a water cleaning system -a trough filter. This is a continually operating filter that removes oil droplets by wires that wet the oil droplets.

Jan 1, 1994

By Michael Leslie Connor

The paper point out the services of the london metal exchanged on the mining.The investigation is divided at two parts: the tradings sessions and dealing and delivery dates. As well as, the london metal exchanged serves the world metal trade at large in three ways: a daily market price, a physical market and the insurance against market fluctuations.

Nov 20, 1969

By C. R. Tinsley

In maybe the world's first in a mine project financing, a US $55 million Rehabilitation Indemnity was given on behalf of the banks in a US $250 million loan to develop the Ranger uranium mine, Northern Territory, Australia. The basis of the financing was an estimate of removal of the tailings and replacement into the pit. The Indemnity was amortized by a sinking fund from the mine's revenues. Such a concept could be valuable for mineral developments in sensitive areas or jurisdictions such as British Columbia or Alaska.

Jan 1, 1992

By Thomas R. Hightower

The Thunderbird plant was erected in Sullivan County in Indiana during 1958-1959. It was first put in operation in March of 1959. At the present time the source of the raw coal is from the Indiana No. 6 seam. The underground operation at present consists of two continuous mining units and two conventional units. The underground is all belt haulage and the first unit with which this paper is concerned is the slope belt. It is a 48-inch-wide inclined belt with 980-foot centers and a lift of 275 feet. The belt is powered with a 350 H, P, motor and has a rated capacity of 600 Tons per Hour. The belt is equipped with a Merrick Scale Company Weightometer, The raw coal moves from the belt to a 6'x12' extra heavy Allis-Chalmers Ripl-Flo equipped with 6" round-hole screens. The over product of the screen is fed into a 10'x20' long McNally- Pittsburg rotary breaker equipped with 4-l/2" round-hole screens. The oversize rock is discharged into a bin that is emptied with a refuse truck. The through-product of the breaker, along with the through-product of the Ripl-Flo, passes either directly to the McNally Giant washbox or to a 36" belt that transports it to a 1000-ton storage bin,' The change from either to the washbox or to the storage bin is made by use of a motorized gate controlled by the plant operator,

Jan 1, 1961

By L. Gutierrez, S. Gering, C. Calderon-Arteaga

"INTRODUCTION Drill and blast (DnB) represents the most important, and sometimes the most costly processes in a mine.. The cost of drilling and blasting operations greatly contributes to the “high cost trends of the overall mining operations” (Afum B. O. and Temeng V. A. 2015). The use of available information to improve the DnB processes can be the difference between a highly expensive process and an optimized one. Mining operations have access to several types of data sets and key information from a wide variety of different systems. This information is normally used to improve, evaluate and apply processes for drilling and blasting. This may include different types of data from the different stages of the process (before, during, and after the drilling and blasting operations), such as hole locations (planned and actual), penetration rates, drill operators, fragmentation (expected and resulting), explosive (design and usage), geology, vibration, and others. This information can be used on its own or combined for further analysis to reduce costs, improve safety, and evaluate results. Fortunately, due to advances in mining software, drill and blast engineers can exploit this data and create reports to evaluate results and improve the DnB process. However, as users start combining information from multiple datasets and establishing standard operating procedures for reporting this data across multiple sites, it becomes valuable to create auditable, automated, and sustainable processes for handling the information. In many cases the task of aggregating and standardizing the data formats has already been completed and is available to consumers via the Enterprise Data Warehouse (EDW). A data warehouse team extracts data from the source systems and transforms it so that it is meaningful for decision support (Barbara H. Wixom, Hugh J. Watson, 2007). Our initial implementation plan for the DnB solution included using data stored at the sites; however we learned early on in the process that much of the work for aggregating and supplying the required data was already completed. The goal for this case study is two-fold: to show how information can be used to make decisions and improve processes, highlighting the value of using an EDW for managing Drill&Blast information; and to discuss how technical challenges encountered during the implementations were resolved. This paper is targeted at users that want to better manage their DnB data or try to set up standardized workflows for using this information. This case study will discuss the process of implementing a DnB workflow at multiple sites within Freeport McMoRan Inc (FMI) using both data at the sites and information available using the EDW. The paper will begin with an overview of the project. The discussion will then describe how DnB processes were used to set up daily workflows in order to provide information for evaluating process and making decisions. The final section will discuss some of the technical challenges and how they were solved, as well as possible next steps for further improving the workflow."

Jan 1, 2017

By A. J. Pearce

MOST mines have a model of some kind to illustrate either geological structure, mining operation, or some special condition or feature of the property. The type used depends on the particular feature or use for which it is intended. At Dome Mines we have developed an interesting and practical application of the horizontal-type model. This model shows the workings of each level horizon plotted on glass. These glass panes are set in frames which, in turn, rest on drawers equipped with rollers which can be pulled out as desired into a light chamber. The features of this model are its rigid steel construction and that any desired number of level plans can be pulled out, eliminating any other interference from other levels. Figures 1 and 2 are photographs of the model cabinet and show its construction and general features. The cabinet is of steel construction with the following overall dimensions: width, 6 ft. 5 in.; depth, 6 ft. 7 in.; height, 5 ft. 2 in. When not in use it can be completely closed-in, making the cabinet practically dustproof. There are 30 drawers, one for each of the 29 levels and one for the surface. The glass in each drawer is divided into two panes, 36 in. by 36 in., of flatdrawn double-diamond 'lustraglass' with about l/32 in. between adjacent edges. The panes are held rigidly in the frames, which are lined with felt strips, and may be adjusted by set screws, four of which on each drawer are shown in Figures 1 and 2. The level workings, on a scale of 1 inch equals 100 feet, are traced in ivory black Windsor & Newtons artist oil paint. Co-ordinate lines are shown in crimson lake, and main geological contacts are shown in their respective colours. Figure 3 is a photograph looking down on one of the levels. The lighting consists of 14 30-watt fluorescent bulbs, with reflectors, under frosted glass. These lamps are much more satisfactory when operated by 60-cycle rather than 25-cycle and, as we had available nearby a source of direct current, this was used. The electrical unit consists of a rotary converter from d.c. to 60-cycle. This arrangement gives perfect lighting, allowing most colours to be easily distinguished. Figure 1 was photographed using this source of light, Figure 2 using an outside floodlight.

Jan 1, 1945

By D. Greene

Close integration of mine planning and operation is a long-sought goal. Success is achieved in varying degrees depending upon mine complexity, size, and sophistication, but too often is more limited than desired. Despite tremendous strides in the development of computer-aided mine planning, digital plans usually must still be converted to error-prone paper maps and physical ground surveys for actual excavation and reclamation. However, advances in GPS, operator displays, and mobile computers now enable equipment operators to work directly from on-board digital plans. CAES offers reduced survey costs, faster field transition time and improved excavation accuracy coupled with faster, more informed decision making regarding key mining operations.

Jan 1, 1997

By B. H. Weber

"Industry generally has become noise-conscious and is realizing that damage to the human ear is expected to become more costly than any other compensation. Noise control has been recognized as a necessity and, fifteen years ago, in co-operation among different countries, inter-national organizations were set up to co-ordinate measures against dangerous noise and the development of silencing devices began. Rock drills for underground operations were particularly scrutinized because of the explosive nature of the noise developing from air escaping from exhaust. This paper describes the results and the present stage of development in the reduction and control of noise on rock drills, with special application to their use in mines."

Jan 1, 1970

By R. Conor, O&apos

Wastewater treatment systems, both industrial and municipal, produce large quantities of sludge which require disposal. Sludge disposal poses significant environmental liabilities, logistical problems, and economic burdens. Minergy Corporation has developed and implemented several new technologies for the recycling of such high volume wastes as sludge, ash, and foundry sand. These technologies perform mineral recovery from the waste material, converting them into construction material and industrial feed stocks which are inert, marketable products. With a continuously operating processing system installed at the waste source, these technologies reduce handling, eliminate downstream liabilities, and reduce disposal costs.

Jan 1, 1999

By Drew Sinha

Success of the environmentally benign semiconductor manufacturing depends on the cost-effective integration of the principles of reduce, recover, reuse and recycle from source material to final product disposal. Increasing demand combined with current shortage of polysilicon provided unique opportunities to recover the silicon waste, caused by various defects, in wafer manufacturing process. Current practices relating to recovery and reuse of waste silicon produced, from crystal growth process to finally polished and epitaxially deposited silicon wafer, at Mitsubishi Silicon America is presented. Future plan to recycle the process generated silicon fines produced during the intermediate steps of the wafer manufacturing process such as grinding, slicing, lapping and polishing is also discussed.

Jan 1, 1998

By A Golsby

Both primary and secondary ventilation is important in underground mining. Secondary ventilation refers to the provision of ventilation to development ends, stopes and services facilities, which constitute secondary circuits tapped off the primary circuit or main through flow of air.An unbalanced primary and secondary combination can cause re-circulation, which is inefficient and potentially hazardous. These inefficiencies extend into operational and other considerations, such as power.Most cost justification analysis covers capital and physical consumables. These analyses are often not comprehensive or holistic. This case study is an example of ‘how to holistically justify’ a secondary ventilation circuit and optimise it to meet all stakeholder needs.This paper particularly addresses the following:how to account for all stakeholders in a secondary ventilation cost justificationthe secondary ventilation componentsthe cost justification outcomes and how to measure themsome of the sensitivitiesthe stakeholdershow to present the justification to meet the stakeholder needssecondary ventilation cost justification.CITATION:Golsby, A, 2015. Secondary ventilation as a value proposition – a case study, in Proceedings The Australian Mine Ventilation Conference, pp 49–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By Carlo Sampaio, Moacir Veras, Aaron Young, Carlo Petter

"Three major challenges for the mining industry are the minimization of energy use, water consumption and environmental impact. Therefore, any technique that reduces milling waste, decreases water usage and shrinks impact during mine life must be considered a major innovation in mining.To these ends, one of the most impactful developments in mining within the last 10 years has been the expanded use of high technology sensors to create preconcentrations of mine ore (Jönsson, 2014). The most common sensors used are charge-coupled device (CCD) cameras, that allow through a red, green and blue (RGB) coloring system, the separation of minerals with different colors, tones and, in many cases, with differences in brightness.More recently, the development and use of dual energy X-ray transmission (DE-XRT) to enable the separation by atomic density of the constituent minerals within a given rock has become a reality. Within this work, a rapid bibliographical review of the CCD and DE-XRT methods and examples of their usage within mining and the industrial minerals sector are presented.Sensor-based sorting in miningAutomation within mining is one of the industry’s current goals. Sensors of various kinds have been used as steps toward automation in recent years, from improving the safety and productivity of haul trucks through the use of cameras and global positioning satellites (GPS), to the divination of slope failures. Just as with other mining areas, sorting has improved dramatically and made great steps toward automation in recent years (Wotruba et al., 2014).Sensor-based sorting (SBS) uses spectromatic sensors to identify intrinsic characteristics of particles and separates them by either mechanical or pneumatic means into different product streams (Wotruba et al., 2014). SBS can be used with great effectiveness to improve gravimetric beneficiation through the selective separation or preconcentration of run of mine ores (ROM)."

Jan 1, 2015

By J. Lorengo, C. H. Bucknam

"Standardization of the Inductively Coupled Plasma Mass Spectrometry (ICPMS) method for gold in cyanide solutions was undertaken to provide a more sensitive method to quantify the gold content than the atomic absorption method standardized in 1994 (E1600). The gold concentration range covered is from 0.001 mg/L Au - 0.3 mg/L Au (0.00005 toz/t Au – 0.009 toz/t Au). Interlaboratory testing was carried out with the assistance of the American Society of Testing and Materials (ASTM) International on two committees to determine the within laboratory and between laboratory reproducibility. Three barren solutions from metallurgical operations were measured in triplicate to satisfy statistical requirements for Committee E1 on Analytical Chemistry of Metals, Ores and Related Materials. A synthetically prepared matrix representing the metallurgical processing solutions was used to prepare Youden pairs to satisfy the requirements of Committee D19 on Water. Results of the standardization program are presented. INTRODUCTION Analysis of process solutions for gold concentration requires accurate and sensitive analytical methods in order to manage process control and metallurgical accounting. Flame atomic absorption spectrophotometry (FAAS) has been the work horse of the assay lab for this duty for decades. In 1994 the FAAS standard method was approved by the American Society for Testing and Materials (ASTM) (1). Six process solutions were collected and preserved by measuring the pH and adjusting to greater than pH 10, if necessary. Duplicate solutions were provided to eight laboratories in random order for analysis by FAAS covering the gold concentration range of 0.19 µg/mL (0.006 toz/t.) to 10.7 µg/mL (0.312 toz/t). A high precision method was used, which involved bracketing the sample with the higher and lower standards nearest to its concentration repeating readings three times and averaging the results. The optimum precision for the FAAS gold method was found to be at the 1.00 µg/mL (0.029 toz/t) and lower scope limit 0.3 µg/mL (0.009 toz/t) gold concentration. Since tailings solutions typically have concentrations below the lower scope limit, use of ICPMS was developed at Newmont USA Limited (Newmont) to assay the lower range solutions."

Jan 1, 2016

By R. T. Swinderman

"Virtually every article you read on safety has a statement to the effect: “It’s obvious that safety pays”. If it is so obvious, why is it so hard to answer these questions? • How does the Maintenance or Operations Manager convince the Plant Manager to spend money from the annual budget for safety improvements? • How does the Plant Manager influence Corporate to prioritize safety improvements? • How does an engineering firm persuade the owner to spend more on design and equipment up front to reduce risk? There are many cultural and structural reasons why it is so difficult to prove the obvious. In my opinion the main culprits are: the almost universally used ‘Low Bid’ process, variations in reporting incident statistics between industries and countries, and, the Generally Accepted Accounting procedures (GAAP) [or International Financial Reporting Standards (IFRS)]. Conventional wisdom is it’s smart not to spend more than you need to meet the minimum regulations and maximize production. But buying on price alone often harms people, degrades the environment, and reduces the company’s bottom line. How can this be? You met the minimum safety requirements and saved money by buying on price. Don’t those savings go right to the bottom line? When you buy on price you get minimum quality, minimum compliance and are often backed corner with no reasonable options to rectify the problems that arise from buying on price instead of buying on long term life cycle cost. Culturally few companies actually ‘walk the talk’. It is trendy to have giant billboards at plant entrances proclaiming world class compliance with quality and safety standards. Annual reports are embellished with safety slogans and sustainability statements. Behind the front gates and the glossy annual reports the message is clear: produce or be replaced. Only a few companies go beyond the window dressing and actually endorse, from the top down, continuously improving their safety culture. Those that do embrace safety, show significant performance advantages over their competition that are reflected in their safety, productivity and environmental records and, ultimately their financial statements and share price. Current accounting (and reward) systems make it unlikely financial managers will accept non-conventional approaches to justifying expenditures on safety because they are driven to report “hard” numbers that can be documented and are within the “GAAP or IFRS Rules.” But in reality, accountants quantify soft or intangible costs all the time in their financial statements. Justifying safety investments is greatly enhanced by quantifying what most financial managers would call intangible costs. Government agencies have no problem assigning intangible costs to justify regulations to improve safety. How many times have you heard that the regulation is justified because the cost to industry is X while the benefit to the society is 2 or 3X? How can they say that without including intangible costs? We find it hard to believe these government claims of benefits to society because we have been trained to think about saving hard direct costs to justify investments."

Jan 1, 2017

By H. -P. Behrendt

Muldenhiütten Recycling und Umwelttechnik GmbH is a lead smelter with a very long tradition. The first reference to the existence of smelters on this site is given by a document of inheritance dated 1318. Originally run as a primary lead smelter, which was supplied with ores from the Freiberg mining district and from overseas, it was required to change it over to secondary raw materials due the abandonment of mining in the Freiberg area in 1968. Today, Muldenhüitten Recycling und Umwelttechnik GmbH has two production lines; lead production from secondary lead and waste incineration, which are closely connected and gain advantage from each other. Installations, improved technologies, and the highly skilled personnel have contributed to satisfy all demands for a production concerning quality and environment.

Jan 1, 2000

By L. Bloom

In 1996, lack of confidence in assaying methods and sample handling affected companies as diverse as Bre-X and Timbuktu. Both share prices and the ability to raise financing are impacted when the quality of assay data is suspect. Overseas projects are subject to enhanced scrutiny when local facilities are used that are unfamiliar to brokers, financing agencies and banks. Quality control systems can be -implemented but there are associated costs. These costs should reflect the risk to the mining company, investors and financiers and the size of the proposed investment. In this regard, assay control call is considered a form of insurance to enhance the value of an exploration or mining project.

Jan 1, 1997

By Toshia Ishii, Jun Kubota, Noriko Kubo

"For steel continuous castings, it is essential to control molten steel velocity at the meniscus, since the velocity is closely related to surface defects on the resultant products. Argon gas is supplied with molten steel into the mold through the submerged entry nozzle to prevent nozzle clogging. In this study, to investigate the influence of argon gas on molten steel flow, a numerical simulation was carried out by a two-phase model. Simulation results indicate that as argon gas bubbles ascend near the nozzle by their buoyancy, they induce the molten steel flow with them and resulted a meniscus molten steel flow from the nozzle to the narrow face of the mold. This flow direction is opposite to the case without argon gas. The calculated data are compared with the experimental data. The comparison shows generally good agreement between the measured and the calculated data. IntroductionIn a steelmaking process, molten steel carried by a ladle is first fed into a buffer vessel called tundish. From the tundish, it is then fed into a continuous casting mold. Molten steel solidifies gradually in the mold (the primary cooling zone) forming a solidified shell. As the solidified shell is just thick enough to support the molten steel at the mold exit, it is withdrawn through the mold by pinch rolls. It is progressively thicken as it is further cooled with water sprays in the secondary cooling zone. At the end of guide roll zone, completely solidified steel is cut into desirable lengths. Schematic view of a typical continuous casting is shown in Figure 1."

Jan 1, 1999