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By O. G. Olvera, E. Asselin, D. Rival

Particle concentration distributions in a leaching tank have been estimated using a novel experimental approach that takes advantage of the galvanic interactions that occur between pyrite (FeS2) particles and a Pt electrode. The collision of FeS2 particles with Pt changes the open circuit potential measured with the electrode due to galvanic interactions. To discern particle collisions with the Pt electrode from experimental noise a simple analytical procedure was first adopted although the use of techniques involving frequency domain analysis is also briefly presented and discussed. Although this method is still under development, it is simple to implement and can yield valuable information regarding the hydrodynamic behavior of solid particles in stirred tanks in very short times. Finally, the advantages and drawbacks of the technique are discussed.

Jan 1, 2014

By Andreas Gaich

COMBINED 3D IMAGES _ Highly detailed 3D geometry _ Identification of fine fractures together with a general impression of the situation _ Dealing with unfavourable outcrop geometries

May 1, 2009

By F. Calizaya, S. Bhattacharyya

"This study presents the results of a set of sound level measurements carried out in three underground mines where auxiliary fans are used regularly. Sound levels as high as 100 dB(A) by the workings and 115 dB(A) by the fans were measured in these mines. These levels are quite high even for intermittent noise. Ventilation layouts and best practices used to overcome potential problems related to overexposure to fan noise in underground hard-rock mines are presented here. Factors such as fan type, rotational speed, and silencer-duct arrangements and their effects on noise attenuation are discussed. INTRODUCTION Auxiliary fans are used in hard-rock mines extensively. They are used to ventilate development headings, crusher rooms, conveyor transfer points, and underground shops. They are also used in developing long tunnels and ramps. Depending on the flow requirements and space restrictions, single or double stage axial fans with rigid or flexible ducts are used. Usually, they are high pressure (3.75 kPa) fans with flow rates ranging from 7.1 m3/s to 30 m3/s. The input power varies from 15 kW to 113 kW (Mutama, 2004; O’Connor, 2008). Typically, a 113 kW fan can produce sound levels as high a 113 dB(A) (Howes, 2005). Silencers are often omitted for cost reduction purposes or when used, they are not well maintained. Furthermore, silencers provide limited attenuation depending on their length and type. Typically, the sound attenuation ranges from 10 dB(A) for a 1 × D silencer to 14 dB(A) for a 2 × D silencer, where D is the fan diameter. In a mine, the silencer is subject to wear and tear, especially when the silencer is used in harsh environments. The interior lining can get clogged and the acoustic fill can get covered by dust and diesel soot, thus reducing the silencer performance. Periodic cleaning of the interior casing can increase the attenuation capacity of a silencer by 6 to 9 dB(A) (Dabson & Acuña, 2017). However, this requires a special silencer design in which the inner cartridge can be removed, the sound absorbing material replaced, the inner casing cleaned and the whole set retrofitted. A number of techniques can be used to reduce auxiliary fan noise in underground mines. These range from selecting the right fan for the job to installing adequate silencers. The choice depends on the air quantity requirement at the working place, cross-sectional area of the opening, duct diameter, fan type (axial or centrifugal) and local restrictions. Auxiliary ventilation layouts and best practices used to overcome potential problems related to overexposure to fan noise in underground hard rock mines are presented here. Factors such as fan type, rotational speed, duct diameter, and silencer-duct arrangements and their effects on noise attenuation are discussed."

Jan 1, 2019

By Gobbs C., J. Lam

"The Eagle East project, accessed from the existing and operating Eagle Mine in the Upper Peninsula of Michigan, is an underground base metal project currently in execution by Lundin. This paper will provide an update on several aspects of ventilation including use of a twin-decline access, innovative airflow crossover arrangement and construction ventilation methodology. Integration into existing mine ventilation systems including construction methodology will also be covered. Performance benchmarks and lessons learned are discussed across these topics.INTRODUCTIONLundin has owned and operated the Eagle Mine since 2013. This hard rock underground mine is located in the upper peninsula of Michigan, USA. High-grade nickel ore is mined using sublevel open stoping mining methods and trucked to surface via haul ramp. The mine, having been in production for four years, is nearing the completion of the initial orebody. A satellite orebody 2,000 meters East of the current workings and approximately 900 meters below surface, was identified that could extend operations until 2023. In 2016, Lundin approved the Eagle East project and construction began in 2017 (Lundin Mining Corporation, 2017).Due to proximity to the existing mine, Eagle East will be both accessed and serviced from the existing Eagle Mine. Ventilation at the Eagle Mine uses two fresh air intakes with direct fired combustion heaters; one at the mine portal feeding fresh air into the ramp and one at a fresh air raise located near the Eagle deposit. The primary ventilation circuit is powered on the exhaust air side, with two 700 hp exhaust fans located at a single return air raise. Underground, fresh air is distributed through the main access decline and fresh air raise (FAR) to the production levels and controlled with mechanical regulators on the exhaust side. The exhaust air is collected through return air raises with a collector/transfer drift on 250 Level and then to the surface through a return air raise (RAR)."

Jan 1, 2019

By K. Esmaieli

The Synthetic Rock Mass (SRM) approach has the potential to capture the mechanical behavior of large rock samples. In order for the method to be used with confidence it is necessary to gain a good understanding of the factors that influences its analysis. This paper reports on a series of numerical experiments, based on field data from a large underground mine, to investigate the influence of intact rock mass strength of a constructed (SRM). A jointed rock mass defined by three fracture sets was simulated by a Discrete Fracture Network (DFN) model. The generated fracture network was subsequently embedded into six different intact rock samples, simulated by a bonded particle model in PFC3D, generating six SRM samples. Each intact rock sample was 7 m × 7 m × 14 m and assigned different mechanical properties. The first intact rock sample was assigned a uniaxial compressive strength of 205 MPa and an elastic modulus of 104 GPa with the UCS and elastic modulus values of the other samples downgraded by 10% until the weakest sample had a UCS value of 121 MPa and an elastic modulus value of 61 GPa. All SRM samples were loaded under uniaxial compression to obtain the complete stress strain curve. It was observed that the compressive strength of the rock mass samples decreased by 10% following the same trend as the rock material strength. However, the elastic modulus of the rock mass samples decreased non-linearly with reduction of the elastic modulus of the rock material. The Poisson's ratio of rock mass samples does not change with decrease of rock material properties. For the post-peak behaviour the results show that both the brittleness index and the residual strength of rock mass samples decreased as the rock material properties degrades.

Aug 1, 2013

By M. H. ElMaghraby

This paper describes the development and validation of a strategy for vibration-based online detection of faults in a particular class of machinery commonly found in industry. This machinery is defined by two basic characteristics that preclude it from the application of standard online condition monitoring approaches. The first characteristic is that the machine is in a constant state of transient operation, thus making it difficult to differentiate between changes in transducer measurements that are due to variable duty and those that are due to machine malfunction or fault. The second characteristic is the fact that the machinery involves multiple sub systems that are subject to identical and simultaneous loading, operating environments and duty cycles. An example of such machinery is a system of multiple hydraulic pumps driving a common load. The monitoring strategy presented here employs an anomaly detection scheme together with methods of signal processing and feature extraction that exploit the parallel duty arrangements of this equipment. Preliminary data is collected from a pair or motor-gearbox assemblies used in a material haulage system in the mining industry. Testing and validation was performed on a mechatronic test bench with both healthy and faulted components. Experiments were carried out to investigate how various configurations of the system were able to detect different types of faults. The results indicate that this approach is effective and merits further investigation.

May 1, 2013

By D. R. Murray

"In 2017, Nutrien Allan Potash remediated a portion of the concrete liner in the production shaft. A set of underslung work platforms and collection boxes were used in conjunction with hydraulic splitters, jackleg drills and hand chippers to excavate and remove the broken concrete. New concrete was placed with the original pressure relief design, using a shaft slip form. Shortly after excavating, it was found that the estimated breaking rate and amount of original concrete in-situ was under estimated. Fifteen feet of excavated concrete (2719cu.ft) and ten feet (of replaced concrete was completed on April 28, 2017, and operation of the production shaft was returned to mine operations. During February 2019, Nutrien Allan Potash began remediation of a portion of the concrete liner in the service shaft. The project is different than the 2017 project, as the remediation has occurred during normal running operations and occurred only on night shift. Rather than hydraulic splitters and hand chippers, the new method includes a concrete saw and mechanical excavator from a working platform. The selected method is based on the lessons learned from the 2017 project in the production shaft. The service shaft project was scheduled to be completed in July, 2019. INTRODUCTION Nutrien Allan Potash is located approximated 75 km east of the city of Saskatoon, Saskatchewan, Canada. There are currently two shafts at Nutrien Allan Potash: the Production Shaft and the Service Shaft, transporting people and material from surface to a depth of 3,335 ft. The Production Shaft was completed in 1967, with one section of grey cast iron tubbing installed in the Blairmore formation between the 1605 and 2037 ft Levels. A second set of cast iron tubbing was installed in the Duperow formation between 2203 and 2463 ft Levels in 1999. The remainder of the concrete as of todays standards is designed as a pressure relief liner. The Service Shaft was completed in 1968, with one section of grey cast iron tubbing installed in the Blairmore formation between the 1600 and 2048 ft Levels. A second set of cast iron tubbing was installed in 1981, with 169 ft installed through the Duperow formation. The remainder of the concrete as of todays standards is designed as a pressure relief liner. PRODUCTION SHAFT REMEDIATION During the second quarter of 2015, the Mine Engineering team were notified of an area of concern in the production shaft. The shaft specialists of Golder Associates Ltd (Golder, formerly Alan Auld Canada) were contacted to complete an inspection of the production shaft liner with emphasis on the area of concern. Based on the inspection and documentation review, it was determined that the concrete at the 2804 foot elevation had been broken out for some time and was retained with #8 rebar bolts with resin encapsulation. The broken concrete was encroaching on the clearance to the conveyance."

Jan 1, 2019

By M. S. Moats, C. M. Campbell

Samples of a high impurity (90.05 wt. % Cu, 4076 ppm Pb, 1939 ppm As and 635 ppm Bi) commercial copper anode were characterized and then electrorefined in a laboratory scale cell. Anode inclusions were examined using backscatter mode scanning electron microscopy and energy dispersive spectroscopy. Hundreds of inclusions were measured for size, morphology and composition. Commonly found inclusions were copper oxide (Cu2O), complex oxides (Cu-Pb-Bi-As-O) and copper selenides/tellurides. The weight percent of lead and arsenic increased with increasing inclusion size up to 4- 5 microns. During electrorefining, starter sheet ductility was negatively impacted by thiourea addition. The importance of arsenic (V) concentration on the electrolyte concentration of bismuth was observed. INTRODUCTION Copper electrorefining is a commercial process used to produce the majority of the world’s refined copper. During this process, impure copper anodes are dissolved electrolytically, and high purity copper is deposited on cathodes. As the anodes dissolve, the impurities either accumulate in the electrolyte or report to solids that form on anodes surfaces or at the bottom of the refining cell. These solids are called slimes. Slimes contain precious metals and are collected for further processing. Slimes are also an important outlet for problem impurities such as lead, antimony and bismuth. The electrorefining process is operated in such a way to encourage the deportment of these elements to the slimes. Impurities in copper anodes have been studied extensively by Chen and Dutrizac (1990, 1993 and 2005). The most common impurities found in modern copper anodes include: Ag, As, Au, Bi, Fe, Ni, O, Pb, Sb, Se, Sn and Te. Impure copper anodes are produced by pyrometallurgical methods and have purities ranging from 97.7–99.7% Cu (Moats et al., 2019). The composition ranges of commercial copper anodes from the 2019 worldwide tankhouse survey are given in Table 1. The concentrations of anode impurities vary widely dependent on the source material and prior processing steps. Based on the work of Chen and Dutrizac, both gold and silver are predominantly found in solid solution within the copper grains while a minor amount of Ag can be found in Cu2(Se/Te) inclusions. Nickel is entirely soluble within the copper grains up to anode compositions of 2500–3000 ppm Ni; above which NiO and kupferglimmer phases are formed (Chen & Dutrizac, 1990). As, Bi, Pb and Sb are found in solid solution within copper and within oxide inclusions typically found along grain boundaries. Oxides are formed due to the presence of 0.13-0.18 wt. % O (Chen & Dutrizac, 1990). This is because during solidification of the cast anodes, impurities are enriched in the liquid phase as the copper grains nucleate and grow. The inclusions form from the last liquid to freeze, which is typically along grain boundaries (Wenzl & Filzwieser, 2007; Wenzl, Filzwieser, Mori & Pesl, 2008).

Jan 1, 2019

By J. H. Gray

"IntroductionIn 1980, Fording Coal Limited started conceptual planning studies which led to major changes in the long-range mining plan at their Fording River Operations. These new plans have been completed and are now in operation.To assist personnel in a timely completion of this major revision to the long-range plan, existing in-house drill hole data base and scheduling systems were used and a computerized Mine Modelling and Planning System was purchased. With these tools, plan s were developed which led to completion of initial access to the peak of Eagle Mountain and the start of mining operations in March 1983. As mining area s open up and new geo logical data is obtained, detailed plan s are being extended and revised.With the geology and mine plan s on line, this work can now be done with less effort and plans ca n be adapted to provide flexibility in mining operations. Changes in market conditions can be accommodated by moving mining operations into different seams for different coal types. The computer systems are used to revise pit designs and schedules accordingly."

Jan 1, 1986

By L. B. Kilius

The composite cathode system based on Ce0.9Gdo.1O2_,5 electrolyte with a painted cathode was used for an intermediate temperature (500-700°C) solid oxide fuel cell. This cathode system was chosen due to its excellent thermal expansion match to the electrolyte, its relatively high conductivity (115 S cm-1 at 700°C), and its low activation energy for oxygen reduction (99 kJ/mol). It was found that the decrease of sintering temperature of the composite cathode system produces a significant decrease in charge transfer resistances to a level of 0.25 SI cm2. The conductivity measurements of porous samples produced values between 40 and 88 S/cm for porosities of 30-40%.

Jan 1, 2005

By F. Chevarin

The reaction of O2 with the carbon anode is considered as the main parasitic chemical reaction affecting Hall-Heroult process anodes. The current study aims at investigating the influence of the microstructure of baked anode on its overconsumption. Samples were removed from different positions of an industrial anode. Density, porosity, Lc and BET specific surface area were measured. The anode reactivity was evaluated based on the weight losses for the samples resulting from the reaction of anode with air at 550°C after 7h. The essential parameters determined to control the air reactivity are closed porosity, Lc and pores with a pore entrance radius of 1.5, 8.5 and 12 p.m. The knowledge of effects of these parameters allows better understanding of the reactivity of anodes and consequently reduction of their overconsumption in electrolysis bath.

Jan 1, 2011

By Carrasco .. P. J. A., R. Parada, I. Saavedra, F. Parada, R. Parra, E. Balladares

In most of the smelters, the management of flue dust has a double objective: the control of minor elements in the anodes and the management of volatiles compounds that can cause contamination due to fugitive gas emissions. This is a special concern when high content of Va elements (As, Sb & Bi) are present in concentrates. We present the results of the experimental study to prove the principle of a novel process that recovers, via volatilization, the As, Sb and Bi in the flue dust as gaseous sulfides, due to a previous sulfidization. In the case of as control any further classical treatment for its stabilization is possible from the gas. The clean calcine can be returned to the smelter avoiding any concentration of these minor elements in the circuit. This process is now tested at pilot scale and shows better indices on carbon footprint than the classical hydrometallurgical process for flue dust.

Jan 1, 2011

By Arsenio Enriquez, Adrian Deneys, Ryan Walton, Jenny Esker

NOx emissions at the Rio-Tinto Kennecott Copper (RTKC) smelter, near Salt Lake City, Utah, are regulated to a compliance emission limit at the Main Stack of 15.9 kg/hr on an annual rolling average. The paper discusses RTKC efforts and improvements, particularly related to the anode furnace operations, since the Smelter modernization in 1995 to comply with the air quality approval limit. This includes replacement of gaseous ammonia to Steam-Gas Refining (SGR) system during the copper reduction stage, upgrade anode furnace oxygen-fuel burner from Praxair’s Stabilized Jet (S-J) to Jet Lance (J-L) technology, development and implementation of operational best practices and continuing to investigate and evaluate NOx control technology and strategy in the industry. In early 2016, changes to Praxair J-L Burner technology on both anode furnaces, utilizing wider lance spacing, was adopted and further improved NOx emission levels well below the compliance limit. INTRODUCTION Since the establishment of the Clear Air Act in 1970, the Environmental Protection Agency (EPA) has been regulating emissions of nitrogen oxides (NOx) to reduce impact on public health and the environment (USEPA, CAA, USEPA, NAAQS). As a requirement of the Clean Air Act, the EPA evaluates the standards for NOx and criteria pollutants on a periodic basis and as a result, standards have been revised and ultimately reduced over time (USEPA, CAA, USEPA, NAAQS, UDAQ, SIP). To remain competitive with changing regulations and in conjunction with Rio Tinto environmental standards for continuous improvement, the RTKC smelter has been motivated to research and implement NOx control strategies. NOx health and environment impacts NOx refers to a group of seven compounds including the most common, nitrogen dioxide (NO2). (USEPA, NO2). The EPA enforces both short-term (1-hr average) and long-term (annual average) standards for NO2 to protect against associated respiratory system impacts. Short-term exposure of elevated NO2 concentrations can aggravate respiratory diseases and lead to symptoms such as coughing, wheezing or difficulty breathing while longer exposures may contribute to the development of asthma and potentially increase susceptibility to respiratory infections. (USEPA, NO2) Additionally, NOx is necessary in the formation of ozone and particulate matter less than 2.5 microns (PM2.5). Ozone concentrations can negatively impact lung function and in some cases, contribute to chronic obstructive pulmonary disease. (USEPA, Ozone) The particles associated with PM2.5 can reduce lung capacity and aggravate heart conditions. (USEPA, PM2.5) For all NOx related pollutants, children and the elderly are generally at greater risk for the health effects. (USEPA, NO2, USEPA, Ozone, USEPA, PM2.5)

Jan 1, 2019

By M. I. Abbas, M. A. Shahin, M. S. Ahmed

"The influence of annealing of galvanized steel (galvannealing) on its corrosion kinetics in a saturated solution of Ca (OH)2 has been studied by means of the polarization resistance method.Galvannealing heat treatment was carried out at 450°C and 550°C for varying times. Annealing at 450°C for 24 hr or at 550°C for 5 hr showed the highest corrosion potential (Ecorr) ~= - 400 m V/ SCE as well as, the lowest corrosion current density (icorr ~= 3 mA.cm-2, while Ecorr and icorr of the unheated specimens were ~= - 1400m V/SCE and == 20 mA.cm-2, respectively.Polarization curves were also obtained for the as-received galvanized specimens together with the galvannealed ones.INTRODUCTIONHeat treatment of galvanized steel (i.e . galvannealing) is carried out at a temperature range of 450°C to 550°C for a time sufficient to convert the free zinc coating to an alloyed one consisting of layers of iron-zinc intermetallic compounds. Table I is a review of the properties of the Fe-Zn intermetallicphases while Figure I is a reproduction - of the Fe-Zn equilibrium phase diagram taken from Hansen.Several authors have studied the formation of intermetallic phases through the interdiffusion of Zn/Fe couples. Their results confirmed the stability of intermetallic phases that could be shown up on the outer surface as a result of galvannealing of galvanized steel.Bernick and Sievertv"" investigated the processing of galvan nealed steel. They found that the galvannealed coating with the best forming qualities consisted of a mixture of Zeta phase and Eta phase."

Jan 1, 1989

By E. Haccuria

Due to the growing share of electrical cars, the use of lithium ion batteries significantly increased. Recycling of these batteries is essential to safely dispose hazardous materials as well as to recover valuables (Cu, Ni, Co, etc.). In order to optimise the recycling process, accurate information is required on the slag phase equilibria for battery smelting. The slag is a multi-component system containing alumina from the battery cases, silica and lime from fluxes, and manganese and lithium from the electrode materials. The present study accurately determined the phase equilibria in the "MnO"-Al2O3-SiO2 sub-ternary system at metal alloy saturation. Particular attention was given to the accuracy and reliability of the final results by highlighting the different reaction pathways, mass transfer- and reaction mechanisms taking place in the system during experiments. This attention enabled improved experimental methodology and measurements. Based on the present study, further measurements will be undertaken in the quaternary "MnO"-Al2O3-CaO-SiO2 system at low "MnO" concentrations, which closely represents the future recycling industrial slags.

Jan 1, 2014

By Olivia Gamache

When working in remote and extreme environments, projects are faced with new challenges for engineering and project execution. This is heightened when also working in countries with a developing environmental regulatory framework, small skilled workforce available for recruitment, and minimal infrastructure such as power, roads, and water. There is an increasing realization that social and environmental aspects need to be built into project execution. Giving proper attention to these issues during project development and execution, and maximizing opportunities is an ongoing challenge.

May 1, 2013

By L. G. Bergh

The experience developing a supervisory control and information systems in a SX pilot plant is presented. The plant is located at the Process Control Laboratory, Santa Maria University, in Chile. In this work, the problem of controlling this process is discussed and related literature is briefly reviewed. Then, an innovative control scheme organized in three levels, local, hydrodynamic, and metallurgical supervisory controls is presented in an architecture including field controllers, PLC, and PC networks. Operating decisions in the metallurgical supervisory control are taken with incomplete information from on-stream analyzers. The control proposed is based on metal and acid concentration predictions of intermediate and exiting streams through the use of dynamic and static models and flow rates and input concentration measurements. Preliminary results are presented. The main objectives are to develop and test intelligent techniques in a hybrid system, and to study measurement and supervisory control problems. It is expected to produce reliable results that will contribute to improve the efficiency of this emerging and important process.

Jan 1, 2007

By Kevin Bell

About Beltek Inc. For more than a decade Beltek, Inc. has been working with national and international organizations to harness and deliver solutions which gain real ebusiness advantages in today's world. Our objectives are to partner with our customers to achieve maximum results, while reducing costs. At Beltek, we provide a commitment to you and your organization's needs. Whether that be delivered by ensuring our services and products are state of the art or by providing a level of personalized service, which makes you feel like the center of attention, Beltek is about adding value to every job we work on. The individuals who work at Beltek quickly become your friends because we share your passion and enthusiasm for the business we are in. That's why every person is a leader in his or her respective fields. Having these individuals as apart of our business ensures you get the best out of our equipment, receive the very latest in advise, problem solving and support. We also pride ourselves on our ability to remain flexible at all times because we know deadlines and schedules can change quickly, so we always go the extra mile to deliver exactly what you need.

May 1, 2004

By D. Shishin

Continuous integrated experimental and thermodynamic modelling work is conducted in Pyrometallurgy Innovation Center (PYROSEARCH). The target is to develop a tool, which is capable to predict the compositions of phases, phase equilibria and enthalpy balance for pyrometallugical processes with higher accuracy. All these can be achieved by thermodynamic calculations based on Gibbs energy minimization algorithm. Recent developments made it possible to predict important factors, such as the chemical solubility of Cu in slag as a function of matte grade, temperature, P(SO2), Fe/SiO2 ratio in slag, wt% Al2O3, CaO and MgO in slag. In industrial practice, it is not only chemical solubility, but the overall amount of slag, which affects the recovery of copper and other valuable metals. It will also impact the energy balance. The presence of solids in the slag matrix influences the physical entrainment of matte in slag. Oxygen enrichment which is sometimes used to control the temperature of the furnace, may also affect the volatilization of minor elements into the gas phase. Same is true if additional fuel is used to compensate for heat balance. In other words, all key process parameters mentioned above are interrelated. Present study demonstrates the ways thermodynamic modelling can be used to link those process parameters on the example of copper smelting. INTRODUCTION Research methodology involving integrated thermodynamic modelling and experimental approach has been recently reported by the authors (Shishin, Hayes, & Jak, 2018 Shishin, Hidayat, Jak, Decterov, & Belov, 2016). Present paper reviews the updates and discusses challenges in the development of a large self- consistent thermodynamic database. The database covers the Al-Ca-Cu-Fe-Mg-O-Pb-S-Si-Zn-(Ag, As, Au, Bi, Ni, Sb, Sn) chemical system. The database works in the environment of FactSage software Bale et al., 2016 and related family of products: ChemApp (Petersen & Hack, 2007), ChemSheet and SimuSage. A list of phases, and thermodynamic models is shown in Table 1. For the copper industry, most important phases are Gas, Slag, Spinel and Liquid matte/metal/speiss. Black-colored elements represent the base system, elements in green can be considered as slag modifiers (slagging elements), and elements in red are minor. Ni is highlighted because it was included recently, in 2019, and currently under development. In addition to copper, the database covers the conditions typical for lead and zinc pyrometallurgical extraction. It is developed in consistency with the experimental results for high concentrations of Pb and Zn. Examples of applications in the present study include the thermodynamic analysis of fluxing for an agitated copper reactor to show the effect of Fe/SiO2, and calculations of copper slag cleaning using reductant.

Jan 1, 2019

Proper water and thermal management is essential for obtaining high performance of Proton Exchange Membrane Fuel Cells (PEMFCs). A steady, two-dimensional water and thermal management model was developed, aiming at considering pressure drop, open circuit voltage variation with stack temperature, water vapor effects on membrane conductivity, which made the model physically more reasonable and more suitable for various operating conditions. The model could predict the distributions of a series of important parameters along the flow channel, and thus the effects of various operating and design parameters on the fuel cell performance could be investigated easily by numerical trial-and-error method. The modeling results compared well with the available experimental results from the literatures. The results also showed that the humidification is crucial for the performance of PEMFCs. The model could be a very useful engineering tool for the optimization of PEMFCs.

Jan 1, 2005