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Stream: Metals & Mineral Processing & the Environment 
in Memory of Dr. Ram Rao  
Paper No.: 8356  
Paper Title: Reducing Water Management Risks Through Processing Changes  
Adrian Dance, SRK Consulting (Canada) Inc.; Chris Kennedy, SRK Consulting (Canada) Inc.; Soren Jensen, SRK Consulting 
(Canada) Inc.;  

Speakers’ List 
Version: May 1, 2014 
Page 58 of 104 
Traditionally, mineral processing plants are designed to achieve the highest recovery of valuable material with limited regard 
for the cost of managing waste products ? both the solids and water component. As an industry, we are confronting ever more 
stringent environmental standards and lower grade deposits requiring more intensive processing and the most profitable 
processing route can, in fact, lead to costly issues downstream. Issues or risks associated with waste management include 
water treatment as well as handling/storage of potentially acid generating material. The capital and operating costs of dealing 
with these issues are significant and should be considered as a consequence of plant design and optimisation. The authors of 
this paper are involved with a number of projects/operations where process operation changes offer opportunities for 
mitigating risks associated with water and waste management. Examples of these changes will be discussed along with the 
estimated benefits to the value of the project and reduction of long term environmental risks. Process changes include: the 
application of water treatment in-plant as opposed to dealing with the entire tailings management facility; the potential to 
reduce acid rock drainage through the preferential liberation or addition of carbonate minerals to the grinding process; and 
the application of alternative reagents to avoid issues and closure risks associated with adverse water chemistry.  
Paper No.: 8656  
Paper Title: Giant Mine Remediation - The First Phase  
Andres Quintero, Golder Associates Ltd., Canada; Sue Longo, Golder Associates Ltd., Canada; Darren Kennard, Golder 
Associates Ltd., Canada;  
Giant Mine is a closed gold mine located in Yellowknife, NWT that operated from 1948 until 2004. Due to Giant?s ore 
association with arsenopyryte, the process to extract gold generated high amounts of arsenic rich gas as a by-product. As of 
1951 several processes were put in place to capture most of this gas in the form of arsenic trioxide dust to be deposited in 
underground chambers. It is believed that approximately 237,000 tonnes of soluble arsenic dust is currently stored 
underground. Giant Mine is currently under care and maintenance by Aboriginal Affairs and Northern Development Canada 
(AANDC), which, in conjunction with the Government of the Northwest Territories, co-manage the Giant Mine Remediation 
Project. In order to protect human health, public safety and the environment Golder Associates Ltd. has begun work to 
stabilize Giant mine. This paper will discus Golder?s work within the Giant Mine Remediation Project framework specifically in 
the following areas: ? Open pit stabilization and closure ? Underground stabilization and closure designs ? Risk assessment for 
the site  
Paper No.: 8359  
Paper Title: Roasting, Fluidized Bed Separation and Hydrometallurgical Treatment of Waste Tantalum Capacitor to 
Recover Purified Tantalum Oxide  
Etsuro Shibata, IMRAM, Tohoku University; Kazumi Sato, IMRAM, Tohoku University; Takashi Nakamura, IMRAM, Tohoku 
University; Hirofumi Ohta, Mitsui Mining & Smelting Co., Ltd.; Hiroyuki Tokuichi, Mitsui Mining & Smelting Co., Ltd.;  
A physical separation technique of tantalum capacitors on waste print circuit boards is in a development phase in Japan. A 
tantalum capacitor consists of an exterior resin (epoxy resin) mixing with silica fillers and tantalum sintered compact. The 
tantalum sintered compact is impregnated with manganese dioxide (MnO2). In this study, we tried to develop the recovery 
process of tantalum oxide from tantalum capacitor by roasting, fluidized bed separation and hydrometallurgical treatments. 
Our purpose is to recover a tantalum oxide with high purity from waste tantalum capacitors. In this process, the exterior resin 
was selectively decomposed by the roasting without oxidation and pulverization of tantalum sintered compact at a proper 
temperature. Furthermore, the decomposed resin with silica filler on the surface of tantalum sintered compact was mostly 
removed by the fluidized bed separation. The surface of tantalum sintered compact was cleaned by the ultrasonic irradiation 
in acid solution to remove MnO2 paste and slightly remained Ag paste and silica filler. The impregnated MnO2 in tantalum 
sintered compact was leached as Mn(II) ion using acid solutions with the reducing effect of the tantalum metal to recover 
purified tantalum oxide.  
Paper No.: 8384  

Speakers’ List 
Version: May 1, 2014 
Page 59 of 104 
Paper Title: Competitive World Copper Concentrate Market and Implications for Japanese Copper Industry Chain  
Kenji Sawada, The University of Tokyo;  
Along with the expanding demand of copper concentarate in Asian countries, the custom-smelters have confronted with 
difficulties of low TC/RC. Now Japanese Copper Industry have 2 options; investment in mine development and/or recycling of 
copper scraps. The strategy of global mining companies will be analyzed, and implications for Japanese Copper Industry will 
be discussed from the viewpoint of sustainability of smelters in Japan.  
Paper No.: 8409  
Paper Title: Improvement of End-of-Life Electronic Products Recycling Process in JX Nippon Mining & Metals Group  
Kazuhito Nishikawa, ; Hifumi Nagai, ; Yoshitsugu Miyabayashi, ;  
JX Nippon Mining & Metals Group (hereinafter ?JX-Metals?) recovers valuable metals from End-of-Life electronic products 
(hereinafter ?EoL products?) economically and environment-benignly, based on the technologies that have been acquired in 
mining, smelting, and refining operations over the years. EoL products including electrical and electronic parts scrap contain 
halogens and hydrocarbons. When such materials are directly treated in the copper smelting process, the following problems 
occur: 1) Corrosion of equipment 2) Degradation of sulfuric acid 3) Abrasion of refractory As a countermeasure to these 
problems, JX-Metals has developed pretreatment processes such as incinerating and residue treating, and has realized the 
following improvements: 1) Removal of hydrocarbons by burning or decomposition in the incinerator 2) Transfer of halogens 
to the incinerator exhaust gas and subsequent removal into washing water 3) Fixation of fluorine into the slag By taking these 
improvements and combining the incinerating process with the melting process, we have made it possible to treat a large 
amount of EoL products efficiently in the copper smelting process. This report presents the pretreatment processes operated 
by JX-Metals and the attained improvements, focusing on the behaviors of halogens in the incinerating and melting processes.  
Paper No.: 8410  
Paper Title: New Trend of the Global Flow of Strategic Metals  
Kohmei Halada, NIMS;  
Current trend of the global flow of strategic metals are analyzed to discuss the strategy of the development of recycling 
technology and alternative technology. In many cases, each global flow of metal is changing from the trilateral structure of U.S., 
EU and Japan in the later 20th century into the convergence to China as the factory of the world. Scrap flows are also changing 
dynamically. A long term change of prices of metal has gotten changed since the entrance of this century. The estimation of 
metal consumption upto 2050, in which the author estimated that many kinds of metal will overshoot the reserve base line, is 
revised considering these change of current trends.  
Paper No.: 8411  
Paper Title: A Zero ? Waste Process for Copper Smelting Slags  
Igor Andres Wilkomirsky, University of Concepcion; Roberto Andres Parra, University of Concepcion; Eduardo Robinson 
Balladares, University of Concepcion; Jan Smit, Ecometales; Maria Paz Merino, ;  
A process to recover copper, molybdenum, zinc and iron (hematite) is being developed in which grinded slags (-65 mesh) are 
sulphated with SO3 at 300-350ºC to form iron, copper and zinc sulphates which are then decomposed at 700-750ºC to form 
hematite, copper and zinc sulphates and oxysulphates and iron molybdate. The SO3 generate is recirculated to the sulphation 
step. The calcine generated in the decomposition step is leached with 25 gpl acid at 50ºC to dissolve the copper, zinc and 
molybdenum for further conventional separation and recovery. The hematite residue, of intense red color, can be used as 
pigment, in the ceramic industry or as pellet feed. The fine crystaline silica remain in the hematite residue.  

Speakers’ List 
Version: May 1, 2014 
Page 60 of 104 
Paper No.: 8421  
Paper Title: Trends on Mercury Management in Gold Processing  
Noelene Ahern, Barrick Gold Corp.;  
Mercury is often present in gold ores and can be released during processing. In view of health and environmental concerns 
related to mercury, the mining industry takes leadership in the responsible management of mercury. This paper reviews 
various aspects of mercury management, including: an overview of mercury deportment in typical gold processing flowsheets; 
trends in mercury legislation impacting the international flow and management of mercury in the gold mining industry; and 
treatment, storage and disposal options for mercury and mercury containing materials.  
Paper No.: 8427  
Paper Title: Surface Chemical Evaluation of Common Gangue Phases in Rare Earth Mineral Flotation Processes in 
Response to the Addition of Oxalic Acid  
Saeed Chelgani, Surface science western; Brian Hart, Surface science western; Lucy Xia, Surface science western;  
In the flotation of Rare earth (RE) minerals, oxalic acid is reportedly acting both as a depressant and pH modifier. Testing has 
established the significance of oxalic acid in the flotation process however its specific role in the recovery or selectivity of REE 
or gangue minerals is not well understood. Pulp pH reduction trials with alternative acids have not shown the same effect on 
the RE mineral recovery or the depression of gangue phases. This work examines the effect of oxalic acid on the surface of 
gangue minerals (quartz, carbonate and hematite) in a series of conditioning tests. Gangue surface analyses by TOF-SIMS 
indicate that oxalic acid inhibits the transfer of secondary ions generated during the conditioning process from one mineral 
phase to another. In this regard, the oxalate ion acts to fix ions in solution through chelation and limit their participation in 
surface adsorption. The surface analyses also identified that the oxalic acid acts to clean mineral surfaces removing activators 
that may ultimately promote collector attachment and flotation. Analyses of micro-flotation stream products from tests 
performed with oxalic acid have shown an improvement in grade in response to oxalic acid addition.  
Paper No.: 8454  
Paper Title: The Process of Reducing Sulphide Oxidation Mining Wastes: From Stoichiometry to Bio-Geochemistry 
1991 to 2013  
Margarete Maria Kalin, Boojum Research Ltd; Carlos Januario Paulo, Boojum Research Ltd; William Neilson Wheeler, Boojum 
Research Ltd;  
Many researchers have tested the addition of various phosphatic materials, including Natural Phosphate Rock (NPR), to 
mining wastes. It was assumed that iron in the waste would form FePO4 precipitates, which would restrict oxygen access to 
pyrite surfaces and reduce leaching. Phosphate additions were based on stoichiometry (phosphate mass to sulphide content of 
waste). Although some interesting, positive results were obtained with NPR, most other additions ultimately failed and the 
approach was abandoned. In 1991, we started to experiment on tailings and waste rock outdoors with NPR, postulating that if 
chemo-lithotrophic microbes on the mineral surface accelerate oxidation, then heterotrophic (oxygen consuming) microbes 
would reduce the oxidation rate. Three independent research organizations also tested this hypothesis with very low NPR 
concentrations. All wastes with NPR produced effluents with low metal concentrations. In 2013, heterotrophs were identified 
and quantified as they grew on German lignite with NPR. Coal wastes without NPR produced no heterotrophs, no biofilms, and 
iron-laden effluents. Wastes with NPR produced iron-free effluents. These data conclusively showed that the oxygen inhibition 
was due to heterotrophic biofilms. We summarize the evolution of our understanding of the effects of NPR on the reduction of 
sulphide oxidation, covering 23 years of research documented in 19 publications.  
Paper No.: 8495  

Speakers’ List 
Version: May 1, 2014 
Page 61 of 104 
Paper Title: Coarse Size Pre-concentration of Low Grade Copper Ores by Dense Medium Separation  
Esau Arinaitwe, University of British Columbia; Yu Hou, University of British Columbia; Libin Tong, University of British 
Columbia; Bern Klein, University of British Columbia;  
A series of dense medium separation (DMS) tests were performed on four low-grade copper ores from Mount Polley mine in 
order to determine their amenability to pre-concentration. The tested ores contained disseminated sulphides, mostly 
chalcopyrite with low copper grades (0.15% ? 0.2%) and relatively high iron grades (4.76% ? 5.63%). The samples were 
screened into different size fractions ranging from 9.5 mm to 50.8 mm and DMS tests were performed on each size fraction at 
various separation densities. The pre-concentration efficiency at different size fractions and separation densities was 
evaluated in terms of metal upgrading and distribution. Mineralogical tests were also performed on selected DMS sink and 
float samples in order to understand the influence of mineralogy on the pre-concentration efficiency. The results showed that 
significant copper upgrading was achieved for intermediate size fractions only at the highest separation density tested. The 
copper recoveries generally increased with particle size at all separation densities. However, it was impossible to upgrade the 
copper content in the ores and achieve acceptable recoveries and mass rejections at the same time. The results obtained using 
iron assays showed clear trends of metal upgrading in the finer size fractions at all separation densities while the iron 
recoveries also increased with particle size. Overall, the results suggest that the optimum separation density and pre-
concentration efficiency is a function of particle size, and that the ore mineralization properties limit the performance of DMS 
as a pre-concentration technology for such low-grade disseminated ores.  
Paper No.: 8449  
Paper Title: Dissolution of Precious Metals Enhanced by Alloying with Less-noble Metals  
Hideaki Sasaki, Institute of Industrial Science, The University of Tokyo; Masafumi Maeda, Institute of Industrial Science, The 
University of Tokyo;  
Dissolution characteristics of metals vary significantly when they form alloys with other elements. Because hydrometallurgical 
processes are essential in separation and refining of non-ferrous metals, it is important to study behaviors of alloys in aqueous 
solutions. The authors have studied dissolution characteristics of precious metals in acid solutions using electrochemical 
measurement. When precious metals are alloyed with Zn, its dissolution is promoted by increase in surface area caused by 
preferential dissolution of Zn. The electrochemical study also revealed that precious metals dissolved from some alloys at 
unusually negative potentials. The underpotential dissolutions are explained by activations of precious metals by dealloying.  
Paper No.: 8029  
Paper Title: Effect of Waste Plastics Addition on the Reduction of Iron Oxide by Sawdust  
James Ransford Dankwah, University of Mines and Technology, Tarkwa, Ghana; Pramod Koshy, University of New South 
Wales, Sydney, Australia;  
This work investigates the effect of waste plastics addition on the reduction of iron oxide by sawdust. Composite pellets of iron 
oxide containing sawdust (SD), high density polyethylene (HDPE) and blends of SD/HDPE were fired under argon in a 
horizontal tube furnace at temperatures between 1300 and 1500 °C. Reduced samples were weighed after 10 minutes of 
reduction and the extent of reduction was calculated from measured oxygen contents of the compact. The results showed 
improved extent of reduction when SD was blended with HDPE. The highest extent of reduction was achieved at SD:HDPE 
ratio of 2:3.  
Paper No.: 8031  
Paper Title: Synthesis of Sulphur-free Metallic Iron from Iron Oxide using High-Sulphur Carbonaceous Materials as 
Reducing Agents  

Speakers’ List 
Version: May 1, 2014 
Page 62 of 104 
James Ransford Dankwah, University of Mines and Technology, Tarkwa, Ghana; Pramod Koshy, University of New South 
Wales, Sydney, Australia;  
This work investigates the potential feasibility of utilising high sulphur carbonaceous materials as reductants in ironmaking 
without transferring the sulphur into the reduced metal. Composite pellets of iron oxide containing end-of-life rubber tyre 
(RT), petroleum coke and blends of RT/coke and petroleum coke/high density polyethylene were heated under argon 
atmosphere in a horizontal tube furnace. Reduced pellets were analysed after 10 minutes of reduction for its sulphur content. 
The results showed that sulphur-free metallic iron can be successfully synthesized using RT and petroleum coke as reductants. 
The level of desulphurisation depends on the nature of blending of the carbonaceous materials.  
Paper No.: 8581  
Paper Title: Effect of Basicity on the TTT and CCT Diagram of Synthetic Slags  
Shaghayegh Esfahani, University of Toronto; Mansoor Barati, University of Toronto;  
Currently, substituting Portland cement with slag cement is one of the most desirable uses of slags. For this application, high 
cooling rates are required to form an amorphous slag. However, it is crucial to develop an ideal cooling path that prevents 
crystal formation and at the same time allows the recovery of high quality heat from slag efficiently. A modified SHTT (Single 
Hot Thermocouple Technique) was used to investigate crystallization behavior of slags, by plotting their TTT (Time- 
Temperature, Transformation) and CCT (Continuous Cooling Transformation) diagrams. Seven different slag compositions 
were prepared all containing CaO, SiO2, Al2O3, MgO with varying basicity (CaO/SiO2 =0.5-1.4). The results indicate with the 
increase of basicity, the TTT and CCT diagrams of glassy to crystalline transformation shift to the left. This agrees with the fact 
that with the increase of basicity, the number of non-bridging oxygen atoms to the number of tetrahydrally coordinated silicon 
atoms (NBO/T) in the Si-O network increases which in turn weakens the Si-O bonding. The weaker the Si-O bonds, the easier 
for the silicate structure to re-order and crystallize. These findings are not only interesting from fundamental point of view, 
they also lead to possible optimization of the slag chemistry for dictating its crystallization behavior, and expanding heat 
recovery options from slag.  
Paper No.: 8636  
Paper Title: Biotechnological recycling of precious and rare metals sourced from end-of-life products and electronics  
Kohshiro Tamaoki, Osaka Prefecture University; Norizoh Saitoh, Osaka Prefecture University; Toshiyuki Nomura, Osaka 
Prefecture University; Yasuhiro Konishi, Osaka Prefecture University;  
We have developed new recycling technologies, based upon an eco-friendly biotechnology, in order to extract precious and 
rare metals sourced from end-of-life products and electronics. Recently we have been focusing on the metal ion-reducing 
bacterium, Shewanella algae, that are able to reduce and deposit gold ions (Au(III)) or PGMs ions (Pd(II), Pt(IV) and Rh(III)) 
into metal nanoparticles at room temperature within 60 min. When processing the aqua regia leachate of printed circuit 
boards, the S. algae cells were able to rapidly and selectively collect gold ions under acidic conditions in the presence of heavy 
metal ions, proposing a new bio-recovery system for gold. This biotechnological procedure also has the potential to allow the 
recovery of PGMs from the leachate of automotive catalysts. The S. algae cells were able to successfully perform the complete 
reduction and deposition of the PGM ions. The ability to collect the PGM ions suggests that this represents a new process for 
the bio-recovery of PGMs from used automotive catalysts. Our proposed biological method enables the rapid and highly 
efficient recovery of precious and rare metals via separation and concentration utilizing microbial reactions at room 
Paper No.: 8264  
Paper Title: Gold Separation from Secondary Materials - A Review  
Shirin Zadeh, Memorial University;  

Speakers’ List 
Version: May 1, 2014 
Page 63 of 104 
Waste Electrical and Electronic Equipment (WEEE) is one of the most fast growing types of solid waste in the world containing 
precious metals especially gold. Gold processing and recovery from secondary materials especially WEEE have been under 
investigation for more than a decade now; however, a comprehensive review for lightening the future path is missing in the 
literature. The aim of this paper would be to discuss the recent advances in gold processing and recovery from secondary 
electronic materials and why it has not become practical yet. The role of pyrometallurgical and hydrometallurgical methods, 
their advantages and disadvantages will be discussed; however, the focus will be on Biosorption and recent advances.  
Paper No.: 8210  
Paper Title: Engineering Properties of Uranium Tailings from Northern Saskatchewan, Canada  
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