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By Abdelaziz Baçaoui, Imane Aarab, Mohammed Derqaoui, Abdelrani Yaacoubi, Khalid El Amari, Abdelmoughit Abidi, Abderahman Etahiri

Numerous researchers have addressed the complexity of the direct flotation separation of apatite from low-grade phosphate ore. The majority of these studies were limited to the micro-flotation scale. In fact, there is no warranty that a reagent scheme that showed a direct flotation of apatite at a micro-flotation scale on pure minerals would automatically replicate the same expected results on the natural ore in the mechanical flotation cell and so was the case for the phosphate ore studied. The overall trend was concentrating apatite in the non-float product. This study aspired to thoroughly assess the flotation performance of this never-exploited low-grade sedimentary phosphate using design of experiments (DOE). Unveiling new insights on such a strategy twist, various parameters and operating conditions, namely, desliming, type of collector and depressant, reagents dosages, conditioning times, flotation time, and pH, were addressed by multiple-factor screening using asymmetrical fractional factorial design followed by statistical interpretations. The collectors tested were the sodium oleate and a fatty acid mixture (FAM). The depressants tested were sodium alginate (NaAL), corn starch, carboxymethylcellulose (CMC), and sodium silicate. The results of the multivariable analysis revealed that desliming, pH, collector dosage, and flotation time significantly influenced the flotation process. Desliming was beneficial for the yield, P2O5 recovery, and SiO2 removal; however, there was still a compromise between grade and recovery. A strongly alkaline pH value of 12 stood out from the whole range. P2O5, CO2, and SiO2 grades of the products and flotation recoveries were improved, except for P2O5 recovery, which was negatively affected. A collector dosage between 2000 and 3000 g/t increased the P2O5 grade and reduced CO2 grade and recovery, enhancing the apatite/carbonates separation. A flotation time of 15 min was significant for P2O5 grade and CO2 recovery, nevertheless, at the expense of yield and P2O5 recovery. The products having initial concentrates of 28.08% P2O5 with a recovery of 88.96% and 29.41% P2O5 with a recovery of 62.71% were obtained using 25 g/t of NaAL and 2000 g/t of the collector FAM and sodium oleate, respectively, at pH 12.

Jun 5, 2022

By J. Armanet

THREE MINING colleges are maintained in France; the École Nationale Supérieure des Mines, of Paris; École Nationale Supérieure des Mines, of Saint Etienne; and the École Supérieure de la Metallurgie et des Mines at Nancy. Besides graduates of these schools, a few graduates of the École Centrale des Arts et MIanufactures and of the École Polytechnique are employed as ]nine managers or engineers; however, most of the latter have taken a graduate course at one of the mining schools.

Jan 1, 1939

By J-N. Oyourou, R. McCrindle, C. J. S. Fourie

"Many mines in South Africa were inappropriately closed and left unattended during the last century. These old mines are potential sources of environmental pollution and may pose a health risk to local populations, since the surrounds contain elevated levels of toxic elements. Soil from the old Edendale lead mine property in Mamelodi Extension 11, east of Pretoria, which was suspected to be contaminated with lead, was analysed. The mine, which primarily extracted galena, was decommissioned in 1938. During this study, the old mine property and surrounds were screened for zinc and lead using a field-portable X-ray fluorescence (pXRF) spectrometer. The metal concentrations, which ranged from 18 to 7 300 mg/kg for zinc and from 50 to 21 000 mg/kg, for lead, were plotted together with the GPS coordinates to produce a concentration distribution map for lead and zinc. This map revealed three anomalies of unacceptably high concentrations, possibly corresponding to areas where ore had been piled or dumped to waste from the old mine. Thirty-six of the soil samples that were analysed by pXRF on site were selected and analysed in the laboratory using inductively coupled plasmaoptical emission spectrometry (ICP-OES) for verification purposes. The zinc and lead concentrations obtained from the two analytical methods were compared using linear regression analysis. Excellent correlation was obtained between the results from the two methods (r2 = 0.99 for zinc and r2 = 0.95 for lead). IntroductionEarly economic development in South Africa was based mainly on mining. However, these activities left a legacy of approximately 6 000 improperly closed mines scattered throughout the country (SAI, 2009; van Schie, 2012). Due to their proximity to settlements, these abandoned mines may pose a potential health risk to humans and an environmental hazard. Mining activities generate large amounts of waste, mostly in the form of overburden and process tailings, which often contain high concentrations of toxic elements. Bioavailable toxic elements can contaminate crops growing in the polluted area (Kala, 2010; Marwa, Meharg, and Rice, 2012) or eventually migrate and detrimentally affect the groundwater (Rösner and van Schalkwyk, 2000). Moreover, sulfides accumulated in mine waste generate acid minewater (Rösner and van Schalkwyk 2000). Unfortunately, owners of mines, closed before the promulgation of the Minerals Act more than twenty years ago (Act 50 of 1991), avoided the compulsory rehabilitation of the environment enforced by this legislation. Toxic elements, such as lead, which were confined within ores, may become exposed through mining and are therefore more easily mobilized within the environment. Elements essential to human and plant metabolism, such as zinc, when exposed by mining activities, may become hazardous due to elevated concentrations (Aslibekan and Moles, 2003; Wuana and Okiemen, 2011). Humans exposed to potentially toxic metals may experience harmful effects as discussed elsewhere (Nriagu and Pacynar, 1988; Wayne and Ming-Ho, 2005)."

Jan 1, 2019

By M. Ramulu, A. K. Chakraborty, P. B. Sahu, C. Bandopadhyay, P. B. Choudhury

Human response to blast induced vibration and air overpressure is an unsolved problem that accompanies excavation process in mining. Pre-assessment and understanding of annoyance due to production blasting is probably one of the most important aspects of a successful mining operation. Complaints arising due to unoptimised blasts lead to various critical situations that hamper production. Inspite, this important aspect has been covered by a limited number of researchers in the world and probably least in Indian context. Human response is a complex phenomenon and the sensitivity of individual also vary from person to person depending on various factors like age, sex, literacy, health and exposure to mining. With ever increasing demand of minerals, opencast mines are expected to approach habitats and thus mine management may witness increased response to blasting. Many developed countries have their own guidelines based on scientific analysis, addressing such environmental problems, where as there are a few studies available in India. This study introspects above phenomenon in tune with mining requirements by analysing direct human response. This paper is based on a case study regarding the human response to blast induced hazards in a Manganese mine situated in central India. Advanced techniques of Critical Path Method and Multiple Response Analyses have been used to unearth important inferences on the response of different crosssections of population residing about the mine to blast induced noise, ground vibration and air overpressure. Various inferences drawn may provide guidelines to the planners, environment or safety departments and blasting official for safe and environment friendly blast design.

Jan 1, 2004

By James K. Gowans

Polaris Mine, a Cominco Ltd. property located on Little Cornwallis Island, Northwest Territories, Canada, (Lat. 75°30'), is the world's most northerly base metal mine. Polaris Mine, which commenced operations in late 1981, is characterized by its unique process barge. The lead/zinc concentrator, powerhouse, shops, offices, dry and warehouse have all been incorporated on a 400 ft. long by 100 ft wide by 65 ft high barge. This process barge was constructed in Southern Canada, at Trois Rivieres, Quebec, then towed 3500 miles into its final resting place on the high arctic. This paper describes the unique design of the barge concentrator and deals with the start-up and continuing operation of the Polaris Concentrator.

Jan 1, 1984

By A. Esterhuizen, S. Essack, H. Joubert, N. Fowler

Tenova Pyromet has developed innovative technologies for copper smelting and electric slag cleaning furnaces. Based on client feedback and requirements, innovative designs have been developed to address key design areas and improve furnace reliability, operability and hygiene. These developments include the NovaLance™ lance system to prevent lance bending on top submerged lance furnaces, the SlagFlo™ slag tapping flow control device to better control bath levels and tapping rate for granulation, and an electrode seal for improved sealing directly onto the electrode casing to allow water-cooled electrode components to be located above the furnace roof. The potential application and benefits of these innovative designs are discussed. INTRODUCTION Tenova Pyromet has a long history in the engineering and supply of innovative electric furnace and related equipment for the base metals and platinum industries. Recently Tenova Pyromet has used its furnace equipment design experience to engineer innovative solutions for top submerged lance (TSL) furnaces, and potentially other furnace technologies. These equipment design solutions are developed to address specific operating challenges and operator requirements. Three of these innovative equipment developments are discussed in this paper. First the NovaLance™ lance technology to prevent lance bending during operation in TSL furnaces, such as used for primary copper smelting, is described. Lance bending has been identified as a significant problem for TSL furnace operators as it causes down time and affects furnace availability. The SlagFlo™ device to control the slag flow rate during tapping has been developed based on specific requirements in the mineral wool industry. The SlagFlo™ device can be used to control slag bath levels in primary smelting, converting and slag cleaning furnaces for base metals including copper. In addition, it can be remotely activated for the safe closing of slag tapholes located upstream from a water granulation system. Finally, Tenova Pyromet developed an electrode seal that seals directly onto an electrode surface. This is a special requirement related to base metals and platinum electric smelting and slag cleaning furnaces where furnace operators prefer to keep the water-cooled electrode equipment above the furnace roof. The seal can be used to seal directly onto the potentially hot and uneven surface of Söderberg, pre-baked and graphite electrodes.

Jan 1, 2019

By Jr. Frank Parrish

This report describes the performance of 17 selected water-injection projects producing from Pennsylvanian-and Permian-age reservoirs. Illustrations depict reservoir structure and thickness, and production and injection history. A selected bibliography of publications pertaining to area oil recovery and geology is included. Tabulations of field and reservoir data reveal marked differences in the projects. Increased oil recovery resulted from injecting water in most cases; however, seven projects recovered less oil than the operators anticipated. Oil recovery by water injection ranged from 0.2 to 262 bbl per acre ft, or 0.1 to 22.5 pct of the initial stock-tank oil in place. Major reasons suggested for poor performance include: (1) Adverse directional horizontal permeability, (2) channeling of injected water through fractures or zones of high permeability, and (3) lack of containment of injected water. One 330-foot-deep project is among the first successful shallow water-floods in north Texas. Another project is the first successful Canyon sand-stone waterflood reported in the area. Previous gas injection in two Cisco sandstone projects did not prevent the reservoirs from responding favorably to waterflooding.

Jan 1, 1965

By MAHESH SHRIWAS, CHRISTOPHER PRITCHARD

Ventilation monitoring and control in mines are becoming an integral part of day-to-day activity for maintaining the health and safety of miners. This paper evaluates potential real-time monitoring solutions for detecting and reducing diesel particulate matter (DPM), mine fires and dust in situ and examines the state-of-the-art use of ventilation monitoring and control in underground mines for detecting and reducing air contaminants to acceptable regulatory limits. In this study, relevant documents, including research papers, trade publications and manufacturer website information, are reviewed to identify research gaps. This paper also includes evaluations of contemporary sensors (airflow, gas, dust and silica), control system and software technologies, data transport systems, the Industrial Internet of Things (IIoT), ventilation network simulators and control devices to identify potential health and safety research gaps. Examples of some mines in Canada, Australia and the United States that have been using ventilation monitoring and controls are included as well. Overall, this review identifies multiple challenges and research gaps in applying mine monitoring and control systems that could be the focus of future research, offering potential improvements to miner safety and health and financial benefits.

By Z Li, Z Yan, T Htet, S Zhang

During the pyrometallurgical processes, a substantial quantity of high-temperature ironmaking and steelmaking slags, generated at temperatures ranging from 1400 to 1600°C, is wasted, as the heat contained in these slags is released into the environment during the tapping process without effective utilisation. On the other hand, a significant amount of energy is required to reheat the cold materials for the manufacturing of glass and mineral-wool, often necessitating the addition of high-silica materials to facilitate the production process. In this study, an innovative approach is presented to harness the heat present in molten metallurgical slags to directly produce new raw materials for glass and mineral-wool manufacturing while simultaneously reducing energy consumption and mitigating CO2 emissions. The theoretical amount of waste glass that can be effectively added in the process has been estimated via thermodynamic calculation. Experimental assessments were conducted to examine the impact of high-silica waste materials on the dissolution, melting and fluidity. Potential recipes for glass and mineral-wool manufacturing were suggested and an assessment of the energy savings, and reduction in CO2 emissions with manufacturing of glass and mineral-wool using this innovative approach were included. It was determined that the processes could lead to a reduction of over 26 kg of CO2 emissions per 100 kg of new material used, primarily due to the utilisation of heat from slag and the accelerated smelting process.

Aug 21, 2024

By E. W. GOODWIN, V. F. Parry, J. B. Goodman, L. D. Schmidt, J. D. Davis, A. C. Fieldner, W. S. Landers, J. L. ELDER

The Heliopore process is essentially an arrangement that uses the waste heat in the exhaust gas of an internal - combustion engine to carbonize coal (noncaking ) or lignite . The gases distilled from the coal furnish fuel for the internal - combustion engine , which drives an electric generator . Thus the main products of the plant are electricity and char . A flow diagram illustrating the principles of operation of the Heliopore process is given in figure 1. The primary equipment consists of a carbonizing retort , gas cooling and scrubbing equipment, a gas storage holder, and an engine to burn the gaseous carbonization products . Coal is charged into the top of the retort while the hot gases from the engine travel upward through special ducts in the retort countercurrent to the coal flow . The hot gases never come into direct contact with the coal . Char is discharged at the bottom of the retort and hot gases at the top . The gaseous products resulting from carbonization of the coal are drawn off by an exhauster through the condensing and scrubbing equipment to take out tar and liquor , then to a gas holder , and finally are burned in a gas engine . The gas engine drives an electric generator and the engine exhaust gases are returned to the retort to carbonize coal . The entire process was intended to be continuous and self - sustaining, and to use coal as the only fuel . The plant may be said to be a large - scale pilot plant in that , although it is of full commercial size , its main purpose is to provide data for the design of others of its type . The installation tested had a daily throughput of about 4 tons of coal . Figures 2 , 3 , and 4 picture some details of the plant and equipment used in the experimental testing . Further details of the equipment and engineering drawings of the castings are shown in figures 8 to 22 in the Appendix .

Dec 1, 1943

By Frederick C. Moore

This paper describes the original planning which actually resulted in the opening of a new aggregate plant located in central New York State. This plant, which is now named the Skaneateles Plant of The General Crushed Stone Company is unique in that the plant itself is a departure not only in design but in concept of operation from the normal aggregate plant the company has operated in the past. Whether or not the concepts which resulted in the Skaneateles Plant are economically feasible remain to be proven by the next few years of operation. By way of background data about our company which will help set the stage for this presentation, we currently operate seventeen stone quarries in the states of New York, Pennsylvania and Virginia. These quarries range in size from 200,000 tons per year to 1,500,000 tons per year with a total annual stone production of approximately 7,500,000 tons. We also produce about 1,250,000 tons of sand and gravel at six sand and gravel plants, 300,000 cubic yards of ready mix concrete, 1,500,000 tons of bituminous concrete, aglime and other minor construction materials. In many cases we are our own best customer consuming a large percentage of the total production of our own aggregates in our various ready mix and blacktop plants. Up to the concept of the Skaneateles Plant our operating facilities have been of the permanent type as opposed to the moveable or portable type plant. The steps involved in the case history of Skaneateles will begin with the basic economic requirements, market research, geologic surveys, land acquisition, zoning and financing and carry through to the final design and construction. We will attempt to show what some of the problems were, how we interpretted them and how we proceeded to solve them. The current results are apparent and can be analysed. The success of the total concepts of the Skaneateles Plant remains for future analysis.

Jan 1, 1968

A production drill rig at a site in Sweden was equipped with a monitoring system to estimate production statistics. Drill running times, drill hole depths, penetration rate, rotation speed, thrust, air percussive pressure and torque pressure were recorded for every 10 mm of hole length for a period of 5 months. Operational activities (rock penetration, tube handling, moving and set-up time) accounted for almost 62% of the time consumed, the remaining 38% being different types of stoppage. Drilling itself, as opposed to handling, took less than 24% of the total time. The results give an indication of how the overall drilling capacity can be increased and which activity should be emphasised. The impacts of automation, new developments and reorganisation on production can also be predicted. Average production was found to be around 100 m/day, but varied between 50 and 160 m/d. The company's specification for the drill rig, before purchase, was that an average production rate of 130 m/d be attained over two consecutive months of drilling - a rate which monitoring shows will not be achieved

Jun 19, 1905

By R. F. Droullard

The Bureau of Mines has used gross alpha and gross beta detectors to continuously measure radiation working levels for a number of years. During this time, improvements have been made in the design and performance of continuous working-level (CWL) detectors. This report discusses the improved designs and some of the operating principles and applications of CWL detectors in the measurement of radon daughter products in mines and dwellings.

Jan 1, 1985

"Hecla Limited has been investigating the potential benefits of using a Spendrup/Compact Filter Technic (CFT) diesel filtration system to remove diesel particulate matter (DPM) from the mine atmosphere to optimize use of the available air. The National Institute for Occupational Safety and Health (NIOSH) has evaluated the scrubber efficiency for dust and DPM which is to be presented in another report. This paper reports on a new mining application of a carbon particulate sensor’s ability to continuously monitor long-term mine DPM levels in conjunction with the scrubber evaluation. Magee Scientific is the manufacturer of the Aethalometer®, a continuous black carbon monitor which has been used extensively in worldwide ambient air quality monitoring networks. Two Aethalometers were used at the mine to assess their potential to continuously track underground DPM levels. In this first underground mine application, the Aethalometers were used to continually monitor black carbon (BC) in the intake and exhaust of the CFT scrubber system. Results showed that an off-the-shelf Model AE33 Aethalometer could continually track underground BC levels for extended periods of time over the course of the six-week trial. Data at the scrubber intake over 14 days of testing showed that DPM filtration would be required less than half of the time to maintain BC levels below 50 µg/m3. If the Aethalometer BC data output were “smart coupled” to control a 200-HP in-mine scrubber, significant electrical cost savings would be realized. INTRODUCTION Mine ventilation airflow quantities are calculated to maintain a safe and healthy environment for miners. Dilution of diesel particulate matter (DPM) is often a key factor used to determine the required quantities of ventilation air (Bugarski et al. 2011). DPM emissions and exposure levels are highly variable depending on mine schedules and activities (Janisko & Noll 2010); however, lacking technology to continuously monitor levels, mine ventilation systems are often over-designed in order to handle worst-case scenarios to ensure that DPM levels are maintained at or below regulatory limits. As mines go deeper it becomes more difficult to supply air, and the development of new shafts for air is not economically feasible (Basu et al. 2008). Cleaning and reuse of available air then becomes an attractive option to maintain good air quality."

Jan 1, 2016

By Y. M. Shneerson, E. E. Zhmarin, E. M. Vigdorchik

One of the Gipronickel Institute activities is research and development of customized leaching technologies. The work is performed in several steps. Leaching kinetics are studied on a lab-scale according to a special procedure. Experimental data are processed using mathematical models of batch and continuous processes. Reliability of kinetic data and preliminary calculations is verified experimentally in laboratory reactors of various capacities. If necessary, certain parameters of the mathematical model are adjusted after pilot plant tests in continuous mode ( 4-reactor train, each with 25 L capacity). The specified kinetic characteristics along with the mathematical model are used for further development of industrial leaching technology.

Jan 1, 2005

By D. S. Robertson

More than 700,000 feet of diamond drilling was completed in the Blind River area between 1953 and 1958. Much of this drilling was at depths which are still not usual in North America. However, as the tendency is to deeper holes, factual data from the Blind River operation may well provide information of value in future programs. Rates of drilling decreased with in-creasing depth, but uncommonly good rates (an average of over 50 feet per day over more than 4,000 feet of hole) were achieved with proper engineering and care. Costs varied as contractors and geologists became familiar with the area Hole deviation in the Blind River area was locally severe and control of the hole trace became a major problem. Careful surveying was necessary and found to be highly re-liable. It was found that control of the hole trace above 1,500 feet was much more difficult than at depths below 1,500 feet. This is explained by the mechanics of the drilling operation. Various methods of controlling hole deviation were attempted and,

Jan 1, 1962

By H. B. Humphrey

The solvents used most widely in industry may be divided into groups according to their chemical and toxicological properties. These groups, with representative members, follow: Petroleum distillates (aliphatic hydrocarbons) Examples: Gasoline, benzine, Stoddard's specification solvents. Alcohols, esters, ketones, ethers, and ether alcohols Examples: Denatured alcohol (ethyl alcohol to which various denaturants may be added), methanol (methyl alcohol), ethyl acetate, amyl acetate (banana oil), acetone.

Jan 1, 1956

By D. A. Rice

As part of its mission, the U.S. Bureau of Mines continues to develop technologies that will enable cost-effective compliance with environmental requirements. To this end, investigations to improve the kinetics of chalcopyrite dissolution by simultaneous grinding-leaching in ferric sulfate solution were conducted using the Bureau-designed turbo mill. The development of such a hydrometallurgical process would provide a nonpolluting alternative to conventional smelter technology. The effects of mill rotational speed and volume percent solids on the leaching time and energy required for copper extraction from chalcopyrite were evaluated. The results of this laboratory study have shown that the simultaneous grinding-leaching of chalcopyrite concentrate using the turbomill is technically feasible with essentially 100 pet extraction of copper being possible at 90° C. An optimal energy consumption of 1,153 kW?h/st of copper leached was found in batch testing with the mill operating at 400 rpm with a slurry containing 35 vol pet chalcopyrite. This energy consumption, while higher than other proposed leaching processes (about 600 kW?h/st), is of the same order of magnitude. Further refinement of the energy requirements would require additional testing using a continuous circuit. Leaching times of less than 1 h, for 80 pct copper extraction, are achievable using the turbomill grind-leach process.

Jan 1, 2010

By A Jafari, N Khalili, M Vahab, P Broumand

This paper presents the implementation of the eXtended Finite Element Method (XFEM) in the general-purpose commercial software package COMSOL Multiphysics for multi-field thermo-hydromechanical problems in discontinuous porous media. To this end, an exclusive enrichment strategy is proposed in compliance with the COMSOL modelling structure. COMSOL modules and physics interfaces are adopted to take account of the relevant physical processes involved in thermo-hydromechanical coupling analysis, namely: the mechanical deformation, fluid flow in porous media and heat transfer. The model preprocessing, level-set-updates, coupling of the relevant physics and postprocessing procedures are performed adopting a coherent utilisation of the COMSOL’s built-in features along with the COMSOL’s LiveLink for MATLAB functions. The capabilities and performance of the proposed approach are investigated by examining several multi-field thermo-hydro-mechanical simulations with reference to the block caving process in mines.

Nov 29, 2022

By Edward B. Cook

INTRODUCTION. THE installation of the Gayley Dry-Air process appealed specially to the management of the Warwick Iron & Steel Co., for the. reason that for fifteen years records had been kept at the works of the company, showing the amount of water entering the furnace in the form of aqueous vapor, and careful observations had been made of its effect upon the working of the furnace. Some years had proved much worse in their effect than others, on account, not only of excessive moisture, but also of great variation in the moisture from day to day, and sometimes within a few hours. It had been found impossible to. make a satisfactory percentage of high-silicon foundry-iron in summer, even on high fuel; and for some years the endeavor had been made so to arrange the sales that, during July and August, only a small percentage of the iron produced would be required to carry more than 2 per cent. of silicon. Our larger furnace, running on basic iron, year after year, produced in February a tonnage 20 per cent. higher than in August, on a much lower fuel-consumption, while, at the same time, the summer months were marked by ? messes," tuyeres closed by slips, and other irregularities, constituting serious additional business losses. It will be easily understood, therefore, that the records made at the Isabella furnace after the installation of the dry blast in 1904 possessed special interest, and were closely watched by us. On the basis of our own experience, we argued that if the moisture could be kept low, and also uniform, the cost of installation would be more than justified. The subject was brought before our Board of Directors in the fall of 1905; and in the spring of 1906 it was decided to install a plant of sufficient capacity to treat 70,000 cu. ft. of air per min., an amount

Nov 1, 1908