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By A. M. L. Cushing, S. Kelebek

Presently, adsorption is one of the effective methods of removing toxic contaminants from waste waters. The contaminants from metal mining industrial operations include an effluent water containing various types of heavy metal species at concentrations beyond the maximum allowable limits, which are 0.5 ppm and 0.3 ppm for nickel and copper species, respectively. Adsorption behavior of copper ions pre-chelated with diethylenetriamine (DETA) and triethylenetetramine (TETA) onto natural bentonite and peat has been investigated. Both natural bentonite and peat was found to be capable of removing these copper-polyamine complexes from aqueous solutions relevant to process water effluents. However, the adsorption capacity of bentonite was significantly higher than that of peat. Two models were used to study the adsorption kinetics: a pseudo-first-order rate expression and a pseudo-second-order rate expression. For both adsorbents, the data conformed best to the pseudo-second-order rate expression. Representation of the experimental data through adsorption models was also investigated. Out of the four cases considered, namely, Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms, it was found that for both bentonite and peat, the copper polyamine adsorption data conformed best to the Dubinin-Radushkevich adsorption model. The Langmuir model also represents the bentonite-copper polyamine adsorption system reasonably well as the second best case, suggesting that the amount adsorbed on bentonite might be a monolayer with strong affinity.

Jan 1, 2015

By M. A. Halim, V. I. Lakshmanan, Z. Jankovic

An innovative mixed-chloride process for the separation of iron from lateritic ore is described. The separation of Fe(III) from leach liquor is an important process step for the recovery of nickel and cobalt. The patented process of Process Research ORTECH Inc. uses a lixiviant containing hydrochloric acid (HCl) and magnesium chloride (MgCl2) for the leaching of lateritic ores/concentrates followed by the selective solvent extraction step of Fe(III) over other value metals such as Ni and Co. The use of MgCl2 increases the activity of the hydrogen ion in the lixiviant, which reduces the consumption of HCl in the leaching stage and enhances the formation of HFeCl4-, thereby increasing the solvent extraction efficiency of Fe(III) with ketone. The process produces high purity iron oxide (Fe2O3) and regenerates HCl by the pyrohydrolysis of the FeCl3 rich pregnant strip solution. The developed process flowsheet is in closed loop, economically attractive and environmentally friendly.

Jan 1, 2015

By Alessandro Navarra, Amir Arash Rafiei, Kristian Waters

Mathematical programming (MP) is fundamental to systems engineering and operations management, but has not been widely adopted by mineral processors. The current paper presents an interdisciplinary approach, using MP to incorporate basic notions of mass balancing into an optimization framework. The optimization is typically related to economic profitability. Two- and three-product formulas are extended to give formal descriptions of alternate modes of operation, and a global representation of the concentrator. At this global level, the framework may assist plant managers to make tactical decisions based on incoming feed data. The MP framework is demonstrated through sample calculations describing a lead-zinc concentrator.

Jan 1, 2015

By Y. Tanaka, M. Maeda, S. Suzuki, C. Tokoro, T. Kato, K. Muto

Boron (B) co-precipitation was investigated with ettringite to establish a cost efficient method of removing B from acid mine drainage. For 25 mg/L of B solution, most appropriate pH for B removal was pH 11.5. The most appropriate amount of reagent for B removal within Japanese effluent standard (10 mg/L) was B:Al:Ca:SO4 = 1:3:9:4.5, which corresponds to the composition of Ettringite (Al:Ca:SO4 = 2:6:3). The effect of silicate, carbonate and temperature on efficiency of B removal is important as groundwater and hot spring water are often contaminated. When silicate and carbonate are present, more Al and Ca salts are needed for B removal since some aluminum and calcium precipitate with silicate and carbonate as kaolinite and calcium carbonate. These precipitates do not contribute much to B removal. As the temperature raised, the most appropriate pH for B removal decreased. B removal became less efficient as monosulfate precipitated more rapidly as ettringite.

Jan 1, 2015

By C. McLachlan, J. R. Donald

"Positioned at the forefront of the seafloor minerals industry, DeepGreen Resources is on track to becoming a leading producer of base and strategic metals obtained from vast high-grade seafloor polymetallic nodule deposits. DeepGreen believes the seafloor minerals industry is an opportunity for developing a more environmentally and societally attractive way to produce cleaner base and strategic metals. Polymetallic nodules contain nickel, manganese, copper, cobalt and other base and strategic metals. Polymetallic nodules represent an exceptional multi-metal-bearing resource, and no current metallurgical operation or flowsheet exists that can recover the primary metallic values while managing the distinct mineralogy. DeepGreen Resources is developing a new process to maximize the business outcomes consistent with the highest environmental standards, including targeting a near zero waste facility. The present paper discusses the history, context and driving forces of polymetallic nodule project development. An overview of DeepGreen?s Nauru Ocean Resources Inc. (NORI) project is presented along with a literature review of polymetallic nodule processing and the on-shore project development scope and plan at DeepGreen Resources is outlined.INTRODUCTION AND CONTEXT Polymetallic Nodules in the Clarion-Clipperton Zone Containing nickel, cobalt, copper and manganese, polymetallic nodules occur in most oceans of the world. The nodules lie on the seafloor sediment. The largest deposit in terms of nodule abundance and metal concentration occurs in the Clarion-Clipperton Zone (CCZ) on vast abyssal plains at a depth of 4,000 to 6,000 metres. The CCZ is located almost entirely in international waters as presented in Figure 1. It has been estimated that the CCZ contains (International Seabed Authority, 2010): •,>21 billion tonnes of nodules; •,>270 million tonnes of nickel; •,>6 billion tonnes of manganese; •,>234 million tonnes of copper; •,>46 million tonnes of cobalt. There are several active hypotheses for the mechanism of formation of the nodules including precipitation, hydrothermal decomposition of basaltic debris, and involvement of microorganisms. Nodules require a nucleus to start forming, which could be a piece of pumice, a shark tooth, old nodule piece, basalt debris or even microfossils like radiolaria and foraminifera. Nodules form concentrically with layers of iron and manganese hydroxides around a core. Although composed mainly of Mn, Fe, silicates and hydroxides, it is the significant content of Ni, Cu, Co, Zn and Rare Earth Elements (REE) that is generating the economic interest in harvesting these deposits. Nodules vary in size from micro-nodules to about 20 cm, the common size being two to eight centimeters. A typical polymetallic nodule and polished cross-section is presented in Figure 2."

Jan 1, 2017

By G. Guiglionda, A. Deschamps, F. De Geuser, M. Langille, B. J. Diak

"Increased demand for light-weighting in passenger vehicles has created a need for strong, light, ductile materials to be used in body-in-white applications. The AA6xxx-series of aluminum alloys are suitable candidates meeting most requirements but can fall short of the formability demands of designers, necessitating an understanding of what controls the formability in this alloy series. This work examines the effect of copper alloying in AA6xxx on the pre-ageing and natural ageing responses of the microstructure and mechanical properties. The changes in microstructure observed by differential scanning calorimetry and hardness testing are related to the work-hardening and strain-rate sensitivity parameters for these alloys measured by tensile testing. An observed asymmetry in the measured strain-rate sensitivity associated with increasing versus decreasing strain rate changes suggests that a different mechanism operates for the two conditions. It is postulated how this asymmetry in strain-rate sensitivity will impact the necking and ductility behaviour of these alloys.INTRODUCTION The widespread use of AA6xxx series alloys in the form of sheets has provided the need for a more thorough understanding of the complex interactions between composition, processing, resulting microstructure and ultimately, the mechanical properties of the alloys. Conventional industrial practices involve the production of rolled AA6xxx sheet (typically 1 mm thick) to be used for body-in-white (BIW) applications for auto body panels (Hirsch, 2004, 2014). The final metallurgical step prior to the shipment of these panels to manufacturers involves a solution heat treatment (SHT) reverting the ageing products of the alloys into solid solution and the product is then shipped to the customer. During this shipping time and while sheets are waiting to be used, the natural ageing (NA) process occurs whereby the strength of the alloys increases resulting in reduced formability. This can result in a product that is unable to meet the formability demands of the automotive manufacturer. As a result, industry has moved towards performing pre-ageing (PA) treatments to prolong the “shelf-life” of the material prior to it having insufficient formability. Once formed into BIW panels, the parts are then painted and subsequently undergo the paint curing heat treatment which consists of a short period of time at medium temperature, typically 20 minutes at 170–190°C. This short artificial ageing (AA) treatment, known as the paint bake (PB), provides additional strength and improved dent resistance for the material, but reduced formability. The PB result is strongly dependent on the PA treatment performed prior to the forming operation. Furthermore, the addition of copper (Cu) to a base Al-Mg-Si composition is known to increase the alloy’s strength. The goal of this work is to study the effect of Cu on strength, strain hardening, and strain-rate sensitivity (SRS) of these alloys, to understand the strength-formability compromise, for two separate heat treatment schedules; one including and one excluding the PA treatment, both followed by NA."

Jan 1, 2018

By Michel Ruel

Most plants do not track how their systems perform. Optimization is the easiest way to benefit from your control systems. We suggest an approach in four phases. The first phase is to assess all equipment to determine the performances for instruments, valves, variable speed drives, and other equipment. The second phase is to remediate instrumentation problems, including the ones pertaining to valves, variable speed drives, analyzers, transmitters. When equipment is in order, loops are put back in automatic mode. If a loop oscillates, use standard default values for this type of loop. The third phase consists in validating the control strategies, properly configuring the systems (control system, programs and parameters, HMI, alarms), and then tuning the loops and control strategies. The fourth phase consists in analyzing the process and expected performances in order to optimize the control loops and control strategies. If performance is not sufficient, a decision tree will be presented to determine the right approach: advanced regulatory control, model predictive control, or fuzzy logic control. Once all steps have been completed, control performance monitoring software is used to sustain the results and pinpoint equipment or loops not performing as stated. Alarm management and rationalization could also be performed after auditing the alarm system, if needed. Examples from plants will be used to demonstrate how this step-by-step method is applied and produces results. INTRODUCTION Maximizing what you already have is the best investment to remain competitive. This article aims to show the benefits of a systematic approach using modern tools to improve plant performance. We at BBA suggest dividing the work in four phases, and a subsequent phase can begin when the previous one has progressed: Assess, Remediate, Stabilize, Optimize, or add advanced control. This approach has been successfully applied to several sites. Examples and illustrations from these plants demonstrate how this step-by-step method is applied and produces results. Under the BBA method, there are four questions to answer before proceeding to the next step. For each control strategy, you should ask the following questions: Assessment: Does it work? Remediation: Do you use it? Stabilization: Is it stable? Optimization: Does it perform? Do you need advanced control?

Jan 1, 2019

By V Dolmage

In 1957 and 1958, ten topographically suitable damsites were investigated along the Peace river between Finlay Forks and Hudson Hope, B.C. Of these, three were eliminated after a reconnaissance survey indicated that the geology was unsuitable for the 650-ft.-high dam contemplated. ?After extensive drilling, five other sites were deemed unfeasible because of geological factors and, in 1959, the two remaining sites were designated as being suitable, one for the high dam and the other for a low dam downstream. The sites are located in the Peace River canyon, on the west and the south? side of Portage mountain, west of Hudson Hope. The site for the large dam, the Portage Mountain dam, has since been investigated by surface mapping, thousands of feet of diamond drilling, a seismic survey, laboratory rock tests and on-site grouting tests in order to establish the possible effect on the dam of all facets of the foundation rocks. Three diversion tunnels, 50 ft. in diameter and 2,200 feet in length, have been driven through massive sandstone and shale, and an intake cut, 500 ft. in length, 200 feet in width and 200 feet in depth, has also been excavated in rock.

Jan 1, 1963

By K. Esmaieli

ABSTRACT We conducted a series of numerical experiments to investigate the influence of rock mass foliation on impact-induced damage on ore pass walls. The 2D Particle Flow Code was used to simulate three distinct rock masses surrounding an ore pass, characterized by foliation angles of 60°, 90°, and 120° (clockwise from horizontal). Subsequently, we projected a rock fragment against the ore pass walls at a constant impact angle and velocity. The resulting damage increase

Jan 1, 2014

By F. Henríquez, V. Iriarte, L. Vinnett, J. Yianatos, F. Díaz

Metallurgical characterizations of the collective (Cu/Mo) and selective flotation plants were carried out in Minera Los Pelambres, Chile. The selective plant allows the valuable minerals of Cu and Mo to be separated. The evaluation involved two surveys consisting of metallurgical sampling as well as residence time distribution (RTD) measurements to determine load distribution. The RTD data were obtained in real-time by means of the radioactive tracer technique. In addition, metallurgical data was reconciled and supported by effective residence times. In the collective plant, a performance comparison of parallel rougher circuits was carried out, which included a bank of six mechanical cells of 250 m3 and banks of nine mechanical cells of 130 m3. In the selective plant, the Cu and Mo evolution along the plant was evaluated. The results in the selective plant allowed for performance evaluation of mechanical and pneumatic cells in primary flotation. In both plants, mineral losses were evaluated and their relationship with circuit configuration (cell types and circuit layout) was determined. The metallurgical characterization was a powerful tool to evaluate circuit performance and to detect improvement opportunities at industrial scale.

Jan 1, 2015

By Henrik Saxén, Mikko Helle

The operation of hot stoves used for preheating the blast in the ironmaking blast furnace has a strong effect on the consumption of reductants, economic performance of and CO2 emissions from the steelmaking site. Generally, it is recommended to maintain as high blast temperature as possible, because this minimizes the rate of reductants in the blast furnace. The blast temperature is affected in a complex way by the time periods of heating and cooling of the stoves, and by the amount of gas combusted in the stoves. Furthermore, as the hot stoves show degraded performance with age, it is a non-trivial task to select optimal operation parameters for the stoves. The paper addresses this computationally by applying a one-dimensional heat-transfer model of the hot stoves for optimization of the performance of the system. The complexity and strong coupling of the decision variables is demonstrated by numerical examples, where the blast temperature is maximized under different constraints.

Jan 1, 2015

By William C. Martin

"Consolidated Sudbury Basin Mines Limited owns two mines, 4 miles apart, near the southwest end of Sudbury Basin. The Errington mine lies close to the north boundary of Creighton Township and about 18 miles by car from Sudbury. The Vermilion Lake mine is in Fairbank Township, on the south side of Vermilion Lake.The first discovery of base-metal mineralization within Sudbury basin was made by James Stobie in 1897 at Stobie Falls on the Vermilion River, half a mile west of the Errington mine. A few years later Alphonse Oilier made a discovery of massive pyrite with base-metal sulphides near the west end of the present Errington workings.No work of consequence was done on these discoveries until 1924, when Joseph Errington acquired options on a large acreage of ground which was later taken over by the Treadwell Yukon Company Limited. After considerable diamond drilling this company sank No. 1 shaft in 1926. In the next three years, a large amount of underground development was done, a pilot mill was constructed and operated for two years. All operations ceased in 1931 with the fall in metal prices. While in operation the pilot mill treated 186,172 tons of ore the average grade of which was 1·07 per cent copper; 1 10 per cent lead; 4·60 per cent zinc; 0·03 ounces gold; and 1 70 ounces silver.Up to the time of closing in 193 l there had been completed at the mine 26, 790 feet of lateral work and 75,500 feet of surface and underground diamond drilling. The company records, however, showed no figures on ore reserves, except broken ore in stopes amounting to about 60,000 tons. A study of the plans, prior to reopening the mine in 1952, showed 1,450 lineal feet of ore (at 1952 prices) opened up by drifting on the 300-foot and 500- foot levels. It is clear that no comprehensive picture of the structure was had at this time. The orebodies were considered to be very irregular pods scattered through masses of quartzite-carbonate in a sheared zone about 800 feet wide. In some way the ore was believed to be related to the tuff-slate contact zone. With this picture it was impossible to make a reasonable ore estimate or even gauge the tonnage potentialities with any feeling of reliability."

Jan 1, 1949

By L. Callele, C. DiGiovanni, L. Li, R. Driver

"Hot-dip galvanizing is a common procedure used to protect structural steels from corrosive environments. However, in a construction project involving welded structural steel platforms by a Canadian steel structures company, numerous connections were found with large cracks in the welded corner joints and T-joints after galvanizing. Historically, in other similar projects by the same industry partner, cracking did not occur making this an unforeseen and new phenomenon. The project explored the mechanical properties of the base material, the thermal stresses induced by the hot-dip galvanizing, and the fracture surface of the cracks. A key feature to note, the fracture surface showed intergranular cracking with no plastic deformation. Lab testing showed the base material exhibited intergranular brittle behavior when heated and fractured at the galvanizing temperature. The transition to a brittle fracture mode is due to temper embrittlement and the segregation of elements in the grain boundaries.INTRODUCTION Galvanization is a common practice for protecting steel structures from the corrosive environment. Hot-dip galvanizing is the most common approach to bonding the zinc layer to the steel, and it is highly cost effective. In the case of welded structures, it is common to do the hot-dip galvanizing process after welding. This is so the protective layer can be applied to the structure as a whole and over the welds. In a recent construction project carried out in industry, a steel frame platform structure measuring approximately 3 m x 7 m was galvanized after welding fabrication. The structure was built of CSA G40.21 350W and CSA G40.20/G40.21 300W plain carbon steels and welded using a metal core arc welding process for the flanges and a flux core arc welding process for the webs of the beams. Due to their size, the platforms underwent a double-dip galvanizing process meaning half of the structures were submerged in the molten zinc path while the other half was exposed to the ambient air. This was repeated for the remaining side. Shortly after the galvanizing process was completed, numerous large cracks were found in the welded joints. Given there was no history of weld cracks after galvanizing in previous similar frames that were double dipped, this failure posed a new and curious problem."

Jan 1, 2017

An Attractive Investment ?Near term low cost and secure PGM producer ?restricted supply legislated demand ?strong pipeline of resource development ?Building Canada?s largest undeveloped PGM-Cu resource ?All work (resource, reserves, DFS, EA) is NI43-101 compliant ?Strong balance sheet: over $8 m in cash with no debt

May 1, 2010

By Farzad Khodabakhshi, Adrian P. Gerlich

"Multi-pass friction stir processing (FSP) was performed to fabricate a new Al-Mg-Graphene nanocomposite. Microstructural developments and distribution of graphene were studied by using electron backscattering diffraction (EBSD) and transmission electron microscopy (TEM) analysis. In the stirred zone (SZ), grain structure was refined down to about 2 µm attributing to the operative dynamic restoration mechanisms and the locking effect of graphene phase. As a result, the yield strength of Al-Mg alloy was improved more than two times due to incorporation of graphene nano-sheets. Also, the indentation hardness resistance of nanocomposite was increased up to ~60%.INTRODUCTION Aluminum-matrix nanocomposites have garnered significant in recent years due to their superior performance and potential advantages for several industrial applications including the automotive and aerospace sectors. Among various reinforcing nano-materials, carbon-based structures featuring sp2 or sp3 hybridization bonds have been found to offer considerably improved physical and mechanical properties. Such carbon allotropes form at micro- and nano-scales including; graphite, carbon nano-tube (CNT), nano-fiber, and graphene. The potential of two-dimensional (2D) carbon materials was introduced in 2004, with the development of graphene as an alternate 2D allotropic form of the carbon structure with a honey-comb lattice at the atomic-scale. It has been shown that it is currently among the strongest materials ever tested with an intrinsic tensile strength of 130 GPa and Young’s modulus of 1000 GPa, and also offers unique thermal and electrical properties.To fabricate metal-matrix nanocomposites reinforced by graphene nano-sheets with typical metallurgical processing techniques, some attempts have been reported in the literature for various solid-state techniques including; hot rolling, mechanical alloying, and friction stir processing (FSP) of pre-cast plates or surface dispersed graphene oxides. The main challenge in those methods was to facilitate the considerable high temperature and pressure for attaining a uniform dispersion of the nano-sheets during the consolidation process. In most cases, significant difficulties have been reported in obtaining a uniform dispersion of graphene within the metal matrix. Among various techniques for production of metal-matrix nanocomposites, FSP has attracted significant attention as a method of surface modification since it was first reported by Mishra et al. In this process, a non-consumable rotating tool is plunged into the surface of material for the aim of microstructure modification. Extreme material plasticity is induced without melting as a result of friction between the tool and workpiece. Frictional heating and severe plastic deformation induced by the FSP process enables metal matrix nanocomposite fabrication by softening the base material and mechanical stirring to disperse the reinforcing nano-materials into the matrix."

Jan 1, 2017

By L. Vollert

"The application of pneumatically-assisted fluidized bed flotation, specifically the ERIEZ HydroFloatTM technology, has found widespread use in non-sulphide processing (particularly phosphate, potash and coal) for the recovery of coarse particles. In gold processing, centrifugal gravity circuits and flash flotation cells are typically employed for the recovery of coarse and near-size liberated gold which tends to accumulate in recycled grinding streams due to bypass to the classifying cyclone underflow streams owing to the higher specific gravity of these gold particles. Early removal of this gold from the grinding circuits contributes toward the reduction of downstream processing losses as a result of overgrinding and particle shape deformation in the case of flotation processing, longer leach residence times in the case of extractive processing, and surface occlusions in the case of both flotation and extractive processing. Furthermore, recovery to bullion attracts higher payment terms by way of comparison to concentrate sales in the case of copper-gold concentrators. This paper assesses the application of pneumatically assisted fluidized bed flotation for the recovery of coarse liberated gold through the analysis of piloting data generated from the operation of a continuously operated 16 inch ERIEZ HydroFloatTM unit treating a sized coarse grinding circuit stream. The paper presents the stage recovery by size performance of the ERIEZ HydroFloatTM unit together with quantitative gold deportment analysis to demonstrate the efficiency with which gold was recovered during this pilot campaign and then compared to more conventional processing units – centrifugal gravity and conventional flotation.INTRODUCTION Newcrest Mining Limited (NML) has identified that an opportunity exists for improving the recovery of coarse composite particles at its current operations, both as a means for improving overall recovery and as an opportunity for early gangue rejection. As such, Newcrest Mining Limited has taken an interest in the application of pneumatically-assisted, fluidized-bed flotation i.e. ERIEZ HydroFloatTM technology. This interest dates back to 2011 with sighter testwork carried out on their Australian-held ore bodies (Kohmuench et al, 2013). Newcrest continues to assess ERIEZ HydroFloatTM potential for coarse composite recovery and, in the case of the topic of this paper, coarse gold recovery based on examples in the literature which demonstrate the efficiency of this technology in this regard (Carmona Franco et al., (2015); Miller et al., (2016); and Kohmuench et al, 2013)."

Jan 1, 2017

By Seong-Ho Ha, Shae K. Kim, Young-Ok Yoon

In the this study, surface segregation of Mg and Ca with Mg addition range from 5 to 10wt% in Al-Mg alloys with Mg+Al2Ca master alloy and its effect on the oxidation resistance were investigated. The addition of Mg+Al2Ca master alloy as the Mg alloying element led to the surface enrichment of Mg and Ca during high temperature oxidation. As a result of the oxidation test by TGA, the oxidation resistance of all the examined alloys was significantly improved with increasing Al2Ca content. The weight change of Al2Ca added Al-5Mg and Al-7.5Mg alloys indicated the complete oxidation resistance during the whole oxidation test time, while a slight weight increase was shown in the case of Al-Mg alloys even with Al2Ca addition. The improvement of the oxidation resistance in Al2Ca added alloys may be attributed to the formation of the protective oxide layer mixed with CaO and MgO on the surface.

Jan 1, 2015

By H. Sato, Y. Sato, T. Ooishi, K. Sakamoto

"Sumitomo Metal Mining Co., Ltd.(SMM)'s Niihama Nickel Refinery(NNR) produces high quality Nickel cathode, Cobaltcathode and other by-products using hydrometallurgical refining process called “MCLE”(Matte Chlorine Leach and Electro-Winning). In 2005,NNR started to use nickel and cobalt mixed sulfide (MS) produced by one of the SMM’s subsidiaries Coral Bay Nickel Corporation(CBNC)’s HPAL plant in Philippines, although its main and the only raw material until then was nickel matte. With start-up of the second HPAL plant at Taganito in 2013, NNR expanded its production capacity of nickel cathode from 41,000 to 65,000 tpa and finally achieved its target in 2015 by producing 65,980 tpa. SMM developed the technologies to improve poor reactivity of MS and installed new facilities to cope with increased Cobalt and Sulfur production at that time. This paper describes the technical approach to increase MS treatment with high efficiency.INTRODUCTIONThe Sumitomo Metal Mining Co., Ltd.(SMM)Niihama Nickel Refinery(NNR) produces Nickel cathode, Cobalt cathode and other by-products using Matte Chlorine Leach and Electro-Winning (MCLE) process technology. SMM uses nickel matte and nickel & cobalt mixed sulfide (MS) as raw materials for the MCLE process. Table 1 shows typical composition of these raw materials. Nickel matte had been only raw material until 2005, and with start-up of Coral Bay Nickel Corporation (CBNC) operation in the Republic of the Philippines, MS became major part of it. In 2009, when CBNC doubled its production capacity, NNR also expanded its plant capacity of electrolytic nickel from 36ktpa to 41ktpa, keeping an eye on the possibility of 65ktpa with oncoming SMM’s second HPAL in Philippines. Poor reactivity of MS was the prime concern at that time because our intention was to increase production with MS. Nickel extraction rate deteriorated with increasing usage ratio of MS in raw materials. To keep high nickel extraction rate under high ratio of MS, NNR developed a new leaching technology. Another concern arising from treatment of MS was Cobalt and Sulfur contents that are much more than those of nickel matte as shown in Table 1.NNR introduced new technology of solvent extraction process as to Co/Ni separation process in order to keep cost competitiveness instead of the conventional cobalt oxidation–neutralizing method. As to sulfur products, new sulfur productive facility was installed to improve the exposure to sulfur dust and the hot working conditions for workers. As a result of process development and installation of new facilities against the problem with MSusage,65 ktpa production was achieved in 2015."

Jan 1, 2017

By A. Blackmore, D. Baker, L. Human

"Mechanical mixing equipment is common in a wide variety of mining, metals and process applications, such as hydrometallurgical reactors, solvent extraction, digestors, and tanks for storage of slurry or hydrocarbons. Computational Fluid Dynamics (CFD) has been applied successfully to single-phase mechanical mixing problems for several decades and is established as a reliable design tool. As computational power and CFD codes have improved over the years, there have been significant advances in modelling capabilities including improved models of turbulence, interaction of rotating and stationary components, multiphase flows, and modelling of free surface interfaces, for example. This paper will provide an overview of the application of CFD to mechanical mixing problems. First, it will review the traditional single phase Multiple Reference Frame (MRF) approach and introduce a range of advanced modelling techniques. Three examples of the application of CFD to industrial mixing problems will be given. It will be demonstrated that CFD is an effective tool for reducing technical risk in design, for identifying the root-cause of mixing problems, and testing modifications to existing operations."

Jan 1, 2015

By D. P. Bishop, G. J. Kipouros, R. L. Hexemer Jr., I. W. Donaldson, W. F. Caley

Aluminum powder metallurgy (APM) is an advanced metal forming technology frequently employed to fabricate complex structural components in a near-net-shape fashion. Exhibiting nearly 100% material utilization, APM continues to rise in popularity. Recent research initiatives in this field have emphasized the development and processing of advanced 2xxx and 7xxx series alloys. In particular, APM equivalents to wrought 7075 and 2024 have been sought. An overview of work completed in this area is presented. Included are data on the various production stages (powder compaction, sintering, forging, and heat treatment) as well as the microstructure and mechanical properties of the finished products.

Jan 1, 2010