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THE machine from which the following results were obtained makes one of a row of seven at work in the Junction North, Concentration Mill at Broken Hill, New South Wales. It consists essentially of a belt for dressing purposes, which travels round two 12-in drums situated at either end of a wooden frame. This frame is supported on wooden legs, and the whole is affixed to two iron castings, one on either side of the frame. A to-and-fro motion is obtained from an eccentric shaft, which, together with the stationary end of the supporting legs, is carried by the iron castings. A belt drive to the forward drum provides a constant rate of travel to the dressing belt.The top half of the dressing belt is supported on 3-in rollers spaced about 12-in centres along the frame of the vanner. A fairly thick dressing belt is used, and no trouble whatever is experienced from the formation of gutters between the rollers.These belts are 28 ft 4 in long, 4 ft wide, 3-16 in thick, and are made of two-ply 32-oz duck, with a coating of rubber on either side. The surface available for dressing is about 10 ft 6 in x 3 ft 8 in- ie, about 38'5 square feet. The machine is driven atthe rate of 245 i-in strokes per minute, while the dressing belt travels at 15 feet per minute...

Jan 1, 1909

By Jonathan Baggett, Nino Ripepi, Amin Abbasi, Richard Bishop, Juan Monsalve, John Hole

This work focuses on the operational and safety issues associated with karst voids in large opening underground mines. Issues include water inrush, structural instability, and engineering uncertainty in these environments. Coupled with the fracturing prevalent in folded sedimentary rocks, karst voids are complex and challenging ground-control risks. Traditional methods of predicting karst void locations, such as probe drilling, are impeded by the inconsistent spatial distribution and variable sizes of the features as reported by Li et al. (J Rock Mechan Geotech Eng:232–242, 2010) and Hassan et al. (Procedia Chem 19:737–742, 2016). Ground-penetrating radar (GPR) is a geophysical technique that transmits radio waves into a medium and subsequently detects reflected waves via a receiver. The travel time and energy of received signals are then processed and interpreted. The difference in conductivity and dielectric permittivity between limestone and open karst cavities causes strong reflections. GPR is frequently used as a geophysical surveying technique in several industries; however, there is a lack of published research on underground mining GPR applications as reported by Zhao et al. (2015a; Geophys J Int:62–71, 2015b) and Eskelinen and Pellinen (Constr Build Mater:888–898, 2018). The purpose of this work is to demonstrate the use of GPR in an underground stone mine and to discuss the importance of karst void detection ahead of mining.

By K Gordon

A methodology for assessment and remediation of acid mine drainage (AMD) developed at the Sullivan Mine in the West Coast Region has been applied to the closed Blackball Mine, Blackball, West Coast Region. AMD from the Blackball Mine has low pH, high acidity, and elevated levels of iron, aluminium, manganese, nickel, zinc and arsenic. The AMD flows at a variable rate (36 - 101 L/s) into adjacent Ford Creek, causing an increase in acidity and trace element concentrations in the creek. To test the effectiveness of treatment with a simple limestone-based treatment system, a column leaching experiment was conducted over a nine day period. The results show effective removal of acidity, reduction in the concentrations of iron, aluminium, manganese and zinc, and production of alkalinity. To determine if this treatment method reduces the toxicity of the AMD to aquatic invertebrates, a 96 hour ecotoxicity experiment was conducted. The results show a significant decrease in mortality in the treated AMD compared to untreated. The column experiment, in conjunction with the ecotoxicity work, suggest that a passive treatment system consisting of a limestone leaching bed and an open limestone channel may be sufficient to treat the AMD from the Blackball Mine. Further work, such as large-scale treatment trials, is recommended.

Jan 1, 2004

By B. Leong, H. Joubert

Keywords: Pyrometallurgy, furnace, auxiliary equipment, copper slag launders Pyromet has designed copper launders for tapping slag. What makes Pyromet?s launder design innovative and safe is that it does not have any cooling water channels underneath the launder runner, whilst achieving effective cooling of the runner. If matte burn-throughs were to occur through the launder runner, the risk of damaging water channels and the risk of explosions are reduced. In addition, since the cooling water channels are not harmed, the launder is easily repairable and reusable. Pyromet makes use of Finite Element Analysis to optimize the launder geometry to ensure that sufficient energy is removed from the centre of the launder. Factors considered during the launder design include the suitability of the geometry to the client?s needs, experience from existing installations, and ease of fabrication. Pyromet goes so far as to develop procedures for fabricators to ensure that fabrication issues do not compromise the functionality of the launder. When launder orders are received by Pyromet, the entire fabrication process and the functioning of the launders during operations are monitored to ensure that the launder designs are continuously improving with every installation.

Jan 1, 2006

By Christopher Jon Preston

This paper describes a type of ammonium nitrate (AN) produced in a patented experimental atomization/aerodynamic process. This AN exhibits outstanding properties for use as a main ingredient to a new family of AN-based commercial explosives. Micro-particle ammonium nitrate (MP-AN) is produced by atomizing either an 83% or 85% AN solution which has been doped with a two component surfactant NSol 1000 (NSol). NSol imparts some water-resistance as well as provides a means of increasing density and bulk strength. Increased detonation velocities, well in the range of emulsion explosives, can be achieved. The maximum manufacturing temperature is less than 100°C. The methodology has the potential of being environmentally friendly since any effluent can be recycled back into a make-up tank to be re-used by the closed loop method. The process has a small footprint.

Jan 1, 2015

By Gupta R. C

Direct reduction of iron ore by solid reducing agents have been studied extensively and summarised by several authors (Otsuka and Kunii, 1969; Abraham and Ghosh, 1979; Frauhan, 1977; Rao, 1971; Kawasaki, Sanscainte and Walsh, 1962; Ghosh, 1970; Rao, 1979). While studying the reduction behaviour, it is generally agreed that the reduction occurs via gaseous intermediate, generated by carbon gasification reaction which involves mass transfer, heat transfer nucleation and growth, etc through a) reduction reaction occurring at solid reductant, and b) reduction reaction occurring at solid iron oxides, thus making the overall reduction process very complex in terms of clearly defining the reduction kinetics of the system. In addition to this, practical difficulties like correctness of reaction temperature, (Seaton, Foster and Velasco, 1983) difficulties in isothermal temperature studies of reduction, difficulties in monitoring the reduction process while using gaseous reductants and separation of reduction by volatile matter from overall reduction process make the reduction kinetics more complex (Misra).

Jan 1, 1999

The key aspects of process metallurgy that distinguish platinum group metal (PGM) concentrate smelting from that of other base metal sulphide concentrates are presented. These differences include considerably higher input chrome and magnesia contents that directly raise the slag liquidus temperature and have the potential to increase accumulations of refractory spinels. Most importantly, the higher processing temperature required for PGM smelting and the resulting very high matte superheat lead to considerably more onerous smelting conditions than those typical of other smelting operations. This has presented challenges to furnace design and integrity, especially when coupled with the progressive intensification of smelting, involving doubling, and then redoubling, of furnace power inputs over the past 20 years. These power increases have been enabled by increasingly more advanced furnace cooling and structural technologies. Key technologies include strong constant-force spring-loaded bindings acting in three dimensions to minimize infiltration of superheated matte into brick joints, and robust well-cooled tapholes for reliably tapping the superheated matte. The result has been substantially improved productivity, and reduced smelting capital cost outlay per unit of production. A significant challenge, which was not anticipated, presented itself in the form of insidious corrosion of the furnace lining, and especially high-intensity copper cooling elements. Investigation of corrosion in related industries eventually identified chloride-accelerated sulphidation', and this term has been retained as it generically describes the most pertinent aspects of the accelerated low-temperature wear of copper coolers observed in PGM smelting. In addition to discussing the corrosion mechanism, this paper describes a number of solutions that were developed jointly by Anglo American Platinum and Hatch to address the copper corrosion problem. First, new monitoring technologies allowed furnaces to be operated more safely for a longer period of time. Second, a system for replacing corroded coolers from outside the furnace during a fast 'hot' shutdown minimized the impact on furnace operating factor and hearth life. Finally, a corrosion-resistant graphite-protected cooler design significantly improved furnace campaign life, and heralds a more lasting solution to cooler corrosion in PGM furnaces.

Jan 1, 2013

By Christopher J. Bise

INTRODUCTION The transportation of men, supplies, and mined material from an underground operation is the connecting link between the mine plant and the surface plant. Unless the mine is accessed by a drift or adit, some form of hoisting system is necessary for slopes or shafts. This chapter will deal with the selection of wire ropes and hoists, two of the most important consider¬ations when designing a hoisting system for an under¬ground mine. WIRE ROPES General A wire rope is designed to transmit forces longitudi¬nally along its axis. Wire rope is used in a variety of mining applications because of its flexibility, high ten¬sile strength, and dependability. Shaft hoisting ropes and principal slope haulage ropes are usually custom-¬built; however, proper rope selection for slushers, car spotters, etc. should not be overlooked. Wire ropes for shafts and slopes, since they represent the life line for the mines, should be of the very highest quality improved plow steel. This quality is necessary to deal with the conditions of loading, winding, vibration, abrasion, and corrosion. Tables I and 2 display the specifications for the typical wire ropes used for mine haulage applications. The 6 x 19-class haulage rope is used for most hoisting where abrasion is not critical. On the other hand, where abrasion is critical, such as a slope application, 6 X 7-class haulage ropes are preferred. For other mining applications, manufactur¬ers' handbooks should be consulted. Selection The selection of a wire rope for a mining situation consists of simply applying appropriate safety factors to a calculated maximum rope pull and comparing the result to the listed breaking strength of the rope under consideration. Table 3 can be used for determin¬ing the minimum factors of safety for wire ropes. To determine the maximum rope pull, the following quantities must be known: the rope weight in pounds (x), the conveyance weight in pounds (y), and the weight in pounds of the load in the conveyance (z). These values are used to calculate the load due to gravity, the load due to conveyance friction, and the load due to rope friction. When these loads are added together, as shown in Eq. 1, the maximum (static) rope pull (RPS) can be derived:

Jan 1, 1986

By Juliana Mesquita de Andrade

Em sistemas cerâmicos policristalinos as homojunções e heterojunções podem apresentar comportamento elétrico desde completamente ôhmico até com elevada característica retificadora, que no limite é a base do comportamento varistor, o qual é o dispositivo de proteção de sistemas e equipamentos eletro-eletrônicos contra sobretensões mais utilizado. Os óxidos de zinco (ZnO) e de estanho (SnO2) são, individualmente, base dos varistores com melhores comportamentos elétricos. Este trabalho, com base nas caracterizações estruturais por técnicas de microscopia eletrônica de varredura e análises termodilatométricas, e na caracterização elétrica e dielétrica, avalia as propriedades varistoras de cerâmicas à base do sistema misto ZnO-SnO2. Verifica-se a formação de um sistema polifásico apresentando homojunções e heterojunções com diferentes características morfológicas e graus de densificação, exibindo ainda comportamento eletrotérmico com predomínio de características varistoras em função da dopagem da matriz mista ZnO-SnO2. Os resultados obtidos evidenciam a tendência da formação de espinélio (Zn2SnO4) em presença de grãos de SnO2 e do estabelecimento de comportamento varistor (coeficiente de não-linearidade > 10), que pode ser aperfeiçoado por dopagem adicional e por tratamentos térmicos, principalmente quanto à redução da corrente de fuga e da ampliação e estabilização da região não-linear da curva tensão x corrente elétrica.

Aug 7, 2018

By Franklin M. Grynkewicz

The subject of bearing pile performance installed by vibratory hammers has been a matter of increasing study and continued controversy. A recent case study from a major bridge replacement project is discussed which provides encouraging data on the use of vibratory pile hammers as a primary means of pile installation and also presents the problems associated with its general acceptance. The bridge project case study foundations consisted of HP 14 x 89 pile sections, designed to develop capacity primarily in friction. Preliminary tip elevations were determined by traditional static analyses. Production pile installation was performed using an IHC S-70 Hydro-Hammer. Driving criteria and final production pile tip elevations were determined after preliminary indicator pile drive tests and static load test results at bridge pier cofferdam locations. Based on impact driven production pile performance, the Contractor wished to investigate vibratory driven piles as a means to accelerate construction schedule. Dynamic pile testing procedures were used as the primary measurement tool and test results were compared to the production pile drive records and prior static load tests. Field testing consisted of driving and monitoring with the PDA impact driven piles to the design tip elevation. Three vibratory driven piles were installed to the same tip elevation and immediately subjected to impact driving and dynamic testing to compare dynamic pile resistance. The results indicated that the site soil conditions were favorable for vibratory pile hammer installation. Recommendations and procedures for proceeding with vibratory hammer pile installation were presented to the Owner. These procedures included quality control in conformance with latest AASHTO recommendations. The Owner, in spite of the site specific data base and QA/QC procedures, would not accept vibratory pile hammer installation, due to the absence of precedence. It is concluded that for vibratory methods to become accepted a rational method of analysis, design and field QA/QC procedures requires development. In addition, the engineering community and Owners/Agencies must be more open to alternate methods of foundation construction. The continued development of dynamic methods of monitoring vibratory pile installation is considered to be key to the general acceptance of this installation procedure.

Jan 1, 1991

By Floyd D. Varley, C. M. K. Boldt

Toolbox training is often described as short, informal training conducted at a worksite by technically competent persons for the benefit of a work team. The key feature of toolbox training is the focus on a work team and what is important to that group in its workplace. Toolbox training conducted by peers can connect miners and establish the feeling that the hazard is a real threat to them. This feeling can bridge the gap between delivery of a safety message and behavioral changes that can prevent an accident. Toolbox training is a popular form of "maintenance" training that should not be used to teach a new skill. The 10- or 15-minute toolbox session is simply too short a time to teach or learn a new skill and test for skill development. However, the toolbox format is an excellent way to inform workers of changes in workplace rules, conditions, or hazards by bringing the discussion of change to the level of the work group and suggesting how a change will affect the way workers perform their jobs. Toolbox training should be structured to address a very specific hazard. That is, the hazard source should be identified and the effect of the hazard on the worker described. The temptation to discuss a safety subject in broad terms will result in an equally vague result. For instance, discussing "equipment guards" is inappropriate for a 15-minute training session. There simply is not enough time to cover all the hazards and their remedies. A more appropriate topic would be "placing guards on a conveyor return roller" or "hazards of cleaning a conveyor return roller." Each topic is concise enough to allow the trainer time to define a particular threat to the safety of miners and discuss ways to defend against that threat. The clearest way to a safe workplace is to identify hazards methodically and eliminate them. This cannot be done with sweeping, generalized training. Some best practices that will protect a worker from the hazard should be presented, and the hazard should be located at the specific worksite. Toolbox training is an opportunity for the work team to participate in learning and share experiences and knowledge, often through storytelling. Storytelling is an ancient form of passing along information in an entertaining way. It is entertaining because it draws the listener in with imagination and creativity. Stories told within work groups are a way for miners to exchange experiences in which they made mistakes that resulted in an accident or a near-miss and learned a valuable lesson. Thus, co-workers can learn from others without the pain or fear that accompanied the storyteller's learning path. To encourage these shared experiences, the people in the group must be comfortable with one another. Participation doesn't stop with listening to a near-miss story or informing the group of an unsafe work practice. Participation by sharing experiences, knowledge, and skills should lead toward action in changing the unsafe tool, practice, or machine (Wallerstein, 1992). This power to change is called empowerment. Empowered workers use toolbox training sessions to discuss a problem; direct their own knowledge, experience, and talents in the context of their work environment to solve the problem; and put into practice what they have learned by sharing (Baker, 1992). A worker is much more likely to implement changes they have contributed to creating than changes forced upon them. Toolbox training functions best when the group size is small (under 20) and composed of workers with similar job functions. While combining all workers on a shift or multiple shifts may be convenient, the level of participation will drop dramatically as group size increases and participants are less connected. Similarly, when the work group participants are from different job functions, keeping the materials relevant to the individual becomes more difficult. The role of management in the toolbox training system is to communicate among various groups so that all groups at a mine site are hearing the same message. In very small operations, combining work groups can be productive if the trainer can promote open discussions and lead the group to solutions that address the needs of all and not let one group or individual dominate the discussion. WHY USE NARRATIVE METHODS An effective communications tool is to use stories as a means of describing a hazard and its consequences. Historically, using stories to transfer knowledge between individuals of the same and different generations is well established. All good stories share the same elements required to communicate safety principles. Stories require a setting (the part of the workplace), a plot (the circumstances that lead to a hazard), the solution (best practices), the lesson (what can happen), and the result (what will be done to prevent the hazard) (Dennehy, 1999).

Jan 1, 2002

By Charles E. Wait

IT is said by some that the occurrence of a deposit of sulphide of antimony in Southwestern Arkansas has been known for fifteen or twenty years. Whether or not such is the case I am not prepared to say, but I am not able to find any record of such a discovery, or any analysis of antimony ore obtained from that section, published at so early a period. The present discoveries, that seem to be attracting some attention, date back to the winter of 1873-74. At that time a vein of ore was found by Mr. Robert Wolf, in honor of whom the vein was named, and still is called, "the Wolf lode." At the time of the discovery the ore was unknown to the prospector, and its composition was not thoroughly understood in that locality until samples were sent to several analytical chemists, who pronounced it sulphide of antimony-stibnite. Since the discovery of this ore there have been three mines opened, and a number of interesting minerals of the antimonial series have been found. I have had an unusually good opportunity to collect specimens from these mines; and it is owing to the constant inquiry concerning the character of these ores that I have collected for publication the results of quite a number of analyses, sufficient I trust to clearly point out their composition. This is one of the few localities in the United States where antimony ore is found in workable quantities; I say workable quantities, because two different shipments of ore have been made to English reduction works, and in both cases excellent returns were made. The discovery of these deposits will, it is hoped, give rise to a prosperous and remunerative industry at no distant day, and when fully developed they may yield ore in sufficient quantity to supply the regulus for the home demand, thus adding wealth not only to those interested, but also to the State of Arkansas. The three mines are situated in the northern part of Sevier County, and may be reached by the St. Louis, Iron Mountain and Southern Railway to Fulton, thence by wagon-road to Columbus, Nashville, Centre Point, and to the mines. During most seasons of the year the

Jan 1, 1880

By Haijian Shi, Drew Pizzo

This article focuses on the appropriate application of subsurface investigation methods for transmission structures, which are typically designed to resist lateral rather than vertical loads. Currently, the three methods used most often for the subsurface investigation of transmission structures in the field are the Standard Penetration Test (SPT), the Cone Penetration Test (CPT), and the Flat Dilatometer Test (DMT). Each of these methods has advantages and disadvantages, and each is more applicable to some scenarios than to others. To gain a better understanding of these test methods and the implications of using them for various kinds of applications, a comparison study was conducted in the field in Maryland, for three boring locations. Each boring location was explored using each of the three tests as stated. The results of the tests and lessons learned are presented and compared, and these comparisons show that the three test methods agree on the majority of the findings. The results from each test method were also used to derive key parameters such as the soil friction angle for given foundation designs considered in order to establish a clear basis for comparison. Recommendations for performing transmission structure subsurface investigations are made in order to optimize the use of each method and thereby optimizing subsequent foundation designs. INTRODUCTION For overhead transmission structures, the most important structural requirement for determining the foundation design differs from the requirement for other structures such as buildings and bridges in accord with the conditions the transmission structures will need to withstand. In addition to the ability to bear a given vertical load consistent with its use, the foundation must bear lateral loads arising from wind and other weather conditions. The foundation types used most often for overhead transmission monopole structures include concrete drilled pier, vibratory caisson, and direct embedment. In order to determine an appropriate and even an optimum foundation design for any given set of conditions, an appropriate subsurface investigation method or approach is needed. Currently, the standard penetration test (SPT), the cone penetration test (CPT), and the flat dilatometer test (DMT) are the three most commonly used subsurface investigation methods.

Jan 1, 2018

By Paloma Lazaro, Moe Momayez

Heat-related illnesses (HRI) are relatively common in both hot surface and underground mining operations. When workers are exposed to extreme heat or strenuous work in a hot environment, they become prone to heat stress. Heat strain is the result of the body’s response to external and internal heat stress. It is therefore vital for the conditions leading to heat strain be detected and treated in a timely manner. Heat-related illnesses are manifested by exhaustion and heat stroke. The predicted heat strain (PHS) [ISO 7933 (2004)] model has been developed to predict the health condition of the worker in terms of core body temperature and water loss. The PHS model tested in this study is based on eight physical parameters that are measured at different intervals during a work shift. They include air temperature, humidity, radiation, air velocity, metabolic rate, clothing insulation, posture, and acclimatization. The model predictions are then compared with a direct physiological measurement, such as core body temperature. We present the results of an extensive study that monitored and predicted body’s response to heat stress under different environmental and working conditions. The PHS model provided reliable results in most instances in comparison with other prediction methods currently in use in the field.

By B. P. Sereda

The properties, characteristics and phase structure of chamotte refractories produced with the usage of mullitecorund chamotte and caoline have been given. The comparison of new refractory C-45 obtained by us and refractory C-43 produced by traditional method has done. The physical-chemical properties of refractories is reviewed. The visual porosity, density and pore characteristics of given refractories was calculated. It is established that C-45 has the less gas permeability then C-45 that gives melting units more stability. The petrographical microstructures of refractories have been done. The main phase structures and their influence on refractories properties have been observed. It is established that refractories with mullitecorund chamotte adition has more advantages then refractories gained by traditional method and can be applied to melting units.

Jan 1, 2010

By Joel Darmstadter

The position of the coal industry in America’s fuel and power picture remains one of prime importance. Measured in Btu terms, the industry is the country’s leading energy producer and an important exporter. Foreign coal sales yield annual proceeds of about $4 billion. Coal’s one-fifth share of the nation’s energy consumption is nearly as high as that of natural gas. Coal is the electric utility sector’s principal fuel supplier. It accounts for about55% of the electricity generated at power stations.

Jan 1, 1999

By A. J. Wainwright

The Coffee Creek lode gold discoveries are located in the White Gold district (Dawson Range), west-central Yukon, 130 km south of Dawson City and 30 km south of the Golden Saddle gold deposit (Figure 1). Extensive structurally-controlled gold mineralization has been discovered during the 2010 and 2011 exploration drilling campaigns, highlighting this part of the Dawson Range as a significant emerging gold district. [ ] In this contribution we review the geological framework and describe the mineralization styles and metal signatures observed to date on the Coffee project. The main Coffee area is underlain by a 15 km by 4 km geochemical footprint, characterized by discrete linear gold-in-soil anomalies that correspond to various mineralized corridors. Of several mineralized areas tested in the past two drill seasons by diamond core and reverse-circulation (RC) drilling, we focus on the Supremo, Double Double, Latte and Kona zones; areas with the most information obtained from drilling thus far (Table 1; Figure 2).

Jan 1, 2012

By Thiago Pinto Silva

Este estudo teve como objetivo investigar o efeito da adição de minérios com diferentes comportamentos a alta temperatura (assimilação e penetração de fase líquida) nos indicadores de processo em uma sinterização piloto. Para isso, seis sinter feeds foram caracterizados e, em seguida, submetidos ao ensaio de sinterização, considerando diferentes misturas a sinterizar. Foi observado que a substituição parcial de um minério que possui grande capacidade de assimilação por aqueles que assimilam pouco o líquido formado no processo de sinterização, resultou em maior resistência mecânica do sínter. Essa propriedade pode também ser associada ao formato dos poros no sínter produto, que reflete na sua redutibilidade. Em termos de penetração de fase líquida, os resultados indicam relação direta com a resistência mecânica do sínter. Dessa forma, esses ensaios de caracterização, juntamente com os aspectos mineralógicos, químicos e granulométricos, permitem subsidiar a tomada de decisão para a substituição mais adequada de um minério na mistura a sinterizar.

Aug 16, 2017

By Rihab Guellala

In Tunisia, the Paleocene-Eocene series has an important socio-economic interest. It contains profitable oil and water accumulations. Moreover, it encompasses phosphate reserves. The present study uses seismic reflection prospection and borehole data for the reconstitution of the Paleocene-Eocene deposit structure in the Jerid area (southwestern Tunisia), a crucial step for the phosphate exploitation. Firstly, lithostratigraphic correlations incorporating water and petroleum wells were established according to different directions for a tentative approximation of the Paleocene- Eocene deposit geometry by following their lateral evolution. To give more details, seismic reflection profiles were interpreted in the second step. The Paleocene-Eocene formations were associated with their corresponding reflectors on the closest seismic profile using the relation of time and depth in petroleum wells. Analysis of lithostratigraphic correlations shows notable variations in the Paleocene-Eocene series thickness and depth. Seismic profile interpretation explains these variations by highlighting different buried tectonic features. The results confrontation reveals that the phosphatic deposit geometry in the Jerid area is mainly influenced by the (1) emergence of the Saharan platform and the Chott northern chain since the Late Cretaceous, (2) syn-sedimentary normal activity of E-W and NE-SW faults during the Paleocene-Eocene epoch, (3) reverse-reactivation of these faults, and (4) major Tortonian folding phase. This study can enormously enhance the Jerid area socio-economic development by presenting useful findings that may orientate the phosphate exploration.

Aug 15, 2021

By David Stephenson, Hugo Granados, Steven Klohn

"HudBay’s Constancia project is a copper molybdenum concentrator located in southern Peru. In 2010 Ausenco was contracted to perform a feasibility study optimization review which resulted in an improved design with significantly increased throughput capacity at a minimal increase in capital cost. Construction began in 2012 with commercial operation commencing in May 2015. This paper outlines the process plant design as well as describing the plant’s major equipment selections, start-up and early operations experiences.IntroductionHudBay Mineral’s Constancia project is located at 4200 meters above sea level (masl) in southern Peru, approximately 630 km south-east of Lima, Peru. The property can be accessed by road from Cusco, Peru, (approximately 110 km to the north), or from Arequipa, Peru (approximately 215 km to the south). Matarani, accessed via Arequipa, is the closest port.Constancia is located within the Yauri-Andahuaylas metallogenic belt. The region contains several large copper-gold-molybdenum porphyry deposits such as Antapaccay (by Glencore) and Los Chancas (by Grupo Mexico), and copper skarn deposits such as Tintaya (by Glencore) and Las Bambas (by MMG). Constancia’s ore reserves contain copper and molybdenum with trace amounts of gold and silver.Ore is mined by an open-pit operation. The process plant recovers copper and molybdenum concentrates, storing tailings in a conventional tailings management facility. Infrastructure at the site includes a grid power supply (via a 70 km overhead transmission line from Tintaya), water supply, workshops and an accommodation camp. Mine life is 22 years.Site construction works began in 2012 with first copper concentrate produced in late 2014. The project was executed for approximately 1.75B$USD.Ausenco’s design approach focussed on developing a capital efficient copper molybdenum concentrator. This paper outlines key features incorporated in the concentrator design, plant layout and equipment selection, as well as start-up experiences and early operational results."

Jan 1, 2016