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By J. S. Stacbulak

"The main ventilation design features adopted at Inco to safeguard personnel against the effects of fires are described in this paper. Measures taken to prevent and detect fires due to spontaneous combustion, and fires involving conveyor belts, are described in detail.IntroductionConsidering the over-all picture of present-day mining operations, the expenditure required to provide a proper system of mine ventilation and fife control should be regarded as a sound investment that will pay back in increased mining efficiency, improved safety, health, and morale of the miners.Mine ventilation control and mine fife detection and fighting are inseparable, because a ventilation system can spread deadly products of combustion just as efficiently as it does life-sustaining oxygen. Therefore, the possibility of a mine fife occurring is of particular concern.The flirt objective is to prevent a fife. The second objective is to design the ventilation system so that a positive fresh air supply can be ensured on each main level regardless of the location of the fife. The third objective is to be able to detect the fife at an early stage and to extinguish it before it can develop into a major fife.Accordingly, at Inco, very extensive measures are taken to prevent fires and to locate, isolate and extinguish them rapidly. To obtain an early warning, it is not sufficient to know that a fife has started, but it is also necessary to know where the fife is burning."

Jan 1, 1994

By J. S. Stachulak

"The main ventilation design features adopted at Inco to safeguard personnel against the effects of fires are described in this paper. Measures taken to prevent and detect fires due to spontaneous combustion, and fires involving conveyor belts, are described in detail.IntroductionConsidering the over-all picture of present-day mining operations, the expenditure required to provide a proper system of mine ventilation and fife control should be regarded as a sound investment that will pay back in increased mining efficiency, improved safety, health, and morale of the miners.Mine ventilation control and mine fife detection and fighting are inseparable, because a ventilation system can spread deadly products of combustion just as efficiently as it does life-sustaining oxygen. Therefore, the possibility of a mine fife occurring is of particular concern.The first objective is to prevent a fife.The second objective is to design the ventilation system so that a positive fresh air supply can be ensured on each main level regardless of the location of the fife.The third objective is to be able to detect the fife at an early stage and to extinguish it before it can develop into a major fife. Accordingly, at Inco, very extensive measures are taken to prevent fires and to locate, isolate and extinguish them rapidly. To obtain an early warning, it is not sufficient to know that a fife has started, but it is also necessary to know where the fife is burning."

Jan 1, 1994

By James K. B. Booth

The natural crustal abundances of the principle metals of commerce are examined in relation to production and prices for each metal. Two factors, the abundance x price ratio (BP factor) and abundance/production (B/T factor) are listed for each metal. Ideally, for these desirable commercial metals, each factor should be a constant and the same for all metals; comparing the divergences for the full list of metals allows conclusions to be drawn on the relative degree of natural availability of each metal and the ease or difficulty of winning the metal from the earth's crust. Plotting the two factors for each metal over the past decade of steady industrial usage illustrates the anomalous position of copper and, to a lesser degree, molybdenum and it is concluded that over the long term the price of copper will continue to rise steeply. Possible future prices for copper are examined and a suggested preferred order of ranking of the metals as exploration targets would be copper, nickel, tin, zinc, silver, molybdenum and lead, for the near term, with molybdenum possibly increasing its ranking in the list within the next decade.

Jan 1, 1971

By Chris M. Healey

"Abstract - Perhaps the single most significant variable in the evaluation of a mining project is the reserve estimate. Many parameters are considered when estimating reserves, among them geology. This paper examines the link between the quality of a reserve estimate and a good understanding of the geological controls for the deposit. A clear understanding of the geometry is essential to the accurate definition of the shape and size of the deposit. This includes the definition of any structural controls as well as the proper interpretation of the stratigraphy. Further when the distribution of grades is erratic and there is consequently a high nugget effect, there are significant problems in estimating the true grade of the deposit.Two Saskatchewan examples are presented, one with good knowledge of the controls and therefore good estimates of reserves, and the other with a poor understanding of the geology and resultant problems in deriving good estimates. In both cases the reserve estimates at various stages in the project development are compared to actual results from underground work. The first example is the Star Lake Mine where just about all the estimates were within 10% of the actual on both tonnage and grade. The Laurel Lake deposit is discussed to show how problems in interpreting the geological data make reserve estimation very difficult. Laurel Lake has the additional problem of erratic grade distribution."

Jan 1, 1992

By Manqiu Xu, Songtao Yang, Zongfu Dai, Robert Pelton

Five years ago, VALE Base Metals (then INCO), approached Pelton's group at McMaster and described a challenging mineral separations problem. The McMaster group has a strong track record in colloids, polymers, and chemical additives for papermaking; however, they had no experience in mineral processing. They proposed employing hydrophobic nanoparticles to replace conventional low molecular weight, water-soluble flotation collectors. Over the last five years, Vale, together with the Ontario Government (OCE) have funded two graduate students at McMaster who have worked closely with flotation experts at Vale. Experiments involving both very clean model mineral suspensions at McMaster and complex ores at Vale, have shown that hydrophobic nanoparticles do indeed function as collectors. Key nanoparticle properties and mechanisms have been identified and the technology has been protected in patent applications. Efforts to commercialize the technology are on-going. We believe that this project is a good case study demonstrating the advantages of industry-university collaboration and the use of outside experts, who may come up with novel solutions to complex problems.

Jan 1, 2011

By R. Laucournet, E. Billy, M. Joulié

Today Li-ion batteries are considered as one of the most attractive available energy storage solutions. However in order to overcome environmental, legislative and economic issues, the management of used batteries has to be considered and mainly the recycling. The present paper deals with the recycling of used Li-ion batteries and the recovery of high value metals from active materials of electrodes. Lithium nickel cobalt aluminum oxide (NCA) and lithium manganese nickel magnesium oxide (LMNM) cathodes, which contain most of valuable elements typically used in the composition of active materials for Li-ion batteries are investigated by a hydrometallurgy route. The process is divided into two steps: the materials leaching and the elements recovery by a selective chemical separation. Some experimental parameters (acid nature, concentration, time and temperature) are studied to determine the most efficient conditions of dissolution. Then, the valuable elements such as nickel, cobalt and manganese are selectively recovered with a high efficiency close to 100 % and with a high purity by precipitation. By this study, an adaptable hydrometallurgy process can be defined according to the composition of Li-ion batteries to recycle.

Jan 1, 2014

By Mark W. Booth

THE Dominion Steel and Coal Corporation, as a coal mining concern and as a steel industry, has much pumping to do, and the conditions are as varied as it is possible to make them. We are faced with handling large quantities of water at low heads, and small quantities of water at high heads. We have fresh water, we have salt water, and we have highly acidulous water (see Table II). Our pumping problems are concerned chiefly with mechanical reliability, continuous, reliable operation, first cost, and operating cost. The Corporation is actually expending more than 15 per cent of its power consumption at the mines in pumping water, and at the steel plant about 17 per cent; that is to say, 16 per cent of the Corporation's entire power consumption goes into pumping water ( see Table I). We are pumping out of the mines 2 ½ tons of water for every tan of coal that is produced. At the Steel Plant, we are pumping 188 tans of water for every ton of steel we produce. (See Tables III and IV). The mine is pumping at high heads, up to as high as 1,400 feet in one lift ; in the Steel Plant it is, fortunately, at lower heads, 250 feet or 110 lb. being the general maximum. It behooves us, therefore, to look into the question of efficiency. In whatever direction we can gain something, it will be worth while. The centrifugal pump is not an adaptable machine. That is, a pump designed for some particular location and purpose will not always work efficiently if installed in some other place and used for some other purpose. It must generally be designed for the particular job it has to do. Reciprocating pumps are not so sensitive. We have Cameron plunger pumps that can be set up almost anywhere in a mine and they will work, but for big jobs they are apt to be clumsy and the driving power becomes a factor- which is, in fact, the controlling factor in deciding the type of pump we use. One disadvantage of the a.c. induction motor, however, is that its speed cannot easily be controlled. At its rated speed and output, it is a highly efficient machine, but, with any change in these, its efficiency goes all to pieces.

Jan 1, 1944

By P. C. Thurston, T. Setterfield, D. H. Watkinson

"The Maybrun copper deposit IS In a succession of pillowed basaltic flows in the Wabigoon sub-province, northwestern Ontario. The rocks have primary flow morphologies and remarkably well-preserved crystallization textures, including quench-textured plagioclase, in spite of metamorphism to the amphibolite facies. The sulphide assemblage chalcopyrite-pyrrhotite-cubanite with minor sphalerite and pyrite is primarily in interpillow spaces and is stratabound. Basaltic rocks immediately enclosing the copper sulphide minerals have an enrichment in Fe, Mg and K and depletion in Ca and Na relative to surrounding flows. The Maybrun deposit is interpreted to have formed contemporaneously with volcanism and alteration, and was subsequently metamorphosed with the enclosing basalts.IntroductionThe association o f significant base metal accumulations with mafic submarine flows in the Archean is as yet poorly documented. Such deposits, where noted, have typically been small, and are therefore commonly over looked. The Maybrun Mine, a 2.6 x 106-tonne copper deposit in pillowed basalt, has many similarities with large, well-documented volcanogenic deposits. Given the interpretation of the Maybrun Mine to be volcanogenic in origin, there is n o reason why similar processes could not produce large deposit s. This is an important realization in an area where Archean submarine mafic rock s are very common, but frequently are examined only superficially. As gold commonly occurs in deposits such as Maybrun, even modest-sized deposits may be economic. The basalts at Maybrun are remarkable for amphibolite-facies rocks because of their extremely well-preserved delicate volcanic textures, including quench textures.The Maybrun Mine is one kilometre south of Atikwa Lake, in the Wabigoon sub-province of the Superior structural province, 75 km southeast of Kenora, northwestern Ontario, at longitude 93°35'W, latitude 49°25'N (Davies, 1973). Archean metavolcanic and metasedimentary rocks and intrusions underlie the area. Goodwin (1970) concluded that the mafic and minor felsic metavolcanic rocks, as well as the overlying metasedimentary rock s, were an eastward extension of the lower cycle of the Keewatin type section for the Lake of the Woods area. He estimated that the stratigraphic thickness of Keewatin rock s in this area is about 6900 m, of which 87% is basalt. The flows contain numerous interlayered sills, predominantly of basaltic composition; they have been extensively folded, faulted, metamorphosed to amphibolite facies and intruded by numerous felsic bodies, most importantly the Atikwa Batholith."

Jan 1, 1983

By R. L. Bruening, L. Navarro, Izatt. S. R., R. Adiga, R. M. Izatt, N. E. Izatt, A. Sharma, N. R. Patel, B. V. Rao

Bismuth is a notorious contaminant in the electrolytic refining of Cu that can cause cathodes to fail to meet ASTM International standards and not be suitable for use in Cu rod and other downstream products. Bismuth can significantly decrease electrical conductivity, decrease the mechanical strength of the annealed wire, retard recrystallization, and sometimes induce hot shortness during the hot rolling process in the production of rod. As a result, the control of Bi in the refinery tankhouse must be carefully managed. This paper describes how SuperLig® Molecular Recognition Technology (MRT) is being used for Bi removal at the Birla Copper Dahej Copper refinery. The operation of the SuperLig® MRT Bi removal plant is described and data on Bi removal efficiency are presented. INTRODUCTION Hindalco’s Cu division, Birla Copper, operates one of the largest Cu refineries in the world at Dahej, Gujarat; India. The main feed for this refinery is produced at the company’s smelter. Due to its massive production capacity, this operation mainly relies on imported Cu concentrates resulting in a variety of metals being carried out as impurities in the Cu anodes because pyrometallurgical technologies alone are not enough to remove them to the extent required. Metal impurities found in Cu ores include Fe, Zn, As, Pb, Bi, and Sb. During electrorefining, less noble metals dissolve in the electrolyte gradually increasing their concentrations creating the need for electrolyte control mechanisms that remove these impurities with varying degrees of success (Wang, 2004; Navarro et al., 2013.) Bismuth is one of the most significant impurities in a Cu refinery because it has the lowest ASTM product specification. This situation is critical because the Bi potential is very close to that of Cu making it possible to plate in the Cu cathode directly. Also, Bi can precipitate at high concentrations causing floating slimes and reduction of current efficiency (Ballinas, San Miguel, Munoz, & Gyves, 2003). Production of high purity cathodes from feed stock containing a diverse range of metal impurities becomes a major challenge in the refining of Cu (Izatt et al., 2015). In this work, the purification strategy followed by Birla Copper for the removal of Bi using a separation process based on MRT is presented, outlining the loading and stripping performance of SuperLig®83 and the benefits of using MRT over other lower selectivity methods where hazardous materials are produced instead of high purity products.

Jan 1, 2019

By C. D. Rowe, H. S. Mitri, J. Malki, I. Vennes

Ore extraction at great depths creates high stresses around mine openings, which can result in violent rock failure in one of various forms of strainburst. This is especially true with strong and brittle rocks, which can store a large amount of strain energy that is suddenly released at failure. The strength and brittleness of rocks have been extensively investigated in the past. The most widely accepted method for the determination of rock burstability is the strain energy storage index obtained from a non-destructive uniaxial load–unload test. However, the results of this method are not always conclusive, showing less repeatability when the target test load is changed. This study concerns itself with the introduction of microscopic analysis as a tool to help validate the strain energy index results when burstability cannot be warranted based on mechanical property tests alone. In this study, two types of rocks, namely, basaltic komatiite (BK) and felsic norite (FNOR) obtained from Canadian underground mines are examined. The selection is based on the premise that felsic norite is known to be burstable from the mine experience, whereas basaltic komatiite is not necessarily burstable. A total of 60 mechanical properties tests were conducted including uniaxial compressive strength, Brazilian tensile strength, and load-unload tests. Laboratory tests on FNOR consistently exhibit high burstability; however, the results for the BK tests are not conclusive. To seek explanations for the mechanical rock behavior, 18 thin sections were examined with optical microscopy and image analysis. The findings show the tested BK specimens are dominated by alteration products, and all primary igneous minerals are lost. There is minor quartz, garnet, carbonate minerals, talc, and serpentine, which give the rock its ductile properties. The FNOR specimens are found to be relatively fresh and supported by a strong network of plagioclase with minor pyroxene, biotite, and secondary micas, explaining the higher stiffness. This study demonstrates how optical microscopy can complement mechanical property tests to evaluate burstability of rocks.

May 4, 2025

By A. A. Rafiei, J. A. Finch

A previous study comparing n-pentanol and the polyglycol Fl50 showed that the two reagents could give the same gas holdup but with different size bubbles. The finding implies that bubble rise velocity depends on the surfactant (frother) type. A study using bubble swarms supported the frother type effect but bubble interactions were a possible confounding factor. This study resolves the question by measuring the rise velocity of single bubbles of 0.8-2.5mm diameter over a distance :::: 300cm in n-pentanol and F 150. It is shown that at typical frother concentrations used in flotation that the rise velocity in n-pentanol remains comparable to that in water alone while in Fl50 the velocity is significantly reduced. The results confirm the suspected impact of frother type. It is illustrated that in n-pentanol the rise velocity does not reached terminal; while in Fl50 it does and this is the source of the velocity difference. Advances

Jan 1, 2009

By Ree Llewellyn

"It has been estimated conservatively that the costs of wear damage and friction in the Canadian mining and mineral processing industry amount to over one billion dollars per year. These are mainly incurred through the repair or replacement of worn parts and production losses from related equipment downtime. The selection and application of the most appropriate wear protection components and systems, can thus have a very significant influence on productivity, profitability and global competitiveness.Details are presented of the wide diversity of materials used to counteract the varied and often complex wear attack mechanisms that occur in surface mining. The majority are various forms of steels and irons with generally very high hardness. However, they also include relatively soft elastomers and polymeric products.The main characteristics and applications of the different classes are reviewed. Case studies record significant performance improvements achieved through more judicious selections. Finally, some new developments which reduce maintenance charges by substantially increasing wear component life, are described."

Jan 1, 1996

By Phillip J. Mackey, Susumu Okabe

Copper mining and smelting has been carried out in Japan for over 13 centuries and in fact stretching back into antiquity. In 1889, the first electrolytic copper refinery in Japan based on Elkington’s principles was started by Furukawa Mining at Honjyo in downtown Tokyo based on the multiple or parallel system. Within two decades, a number of other copper refineries had begun operation. Interestingly, but perhaps not surprising given Japan’s long history of copper production, this first refinery in Japan commenced just ten years after the first refinery in the USA (1879), and not long after the first plants in Europe. By 1935, as a result of growth in copper demand, there were six domestic copper electro-refineries in Japan with an installed capacity of 97,800 tonnes/a, while actual production was 71,200 tonnes/a. Since about 1932, the majority of these plants were based on the more common parallel or multiple system. In 1946, just after World War II, domestic production capacity had dropped considerably to 29,000 tonnes/a, however with reconstruction, capacity and production expanded rapidly, with production reaching 81,000 tonnes/a in 1955, 187,000 tonnes/a in 1960 and 307,000 tonnes/a in 1965. The introduction of the first refinery and the early ones that followed and subsequent developments are discussed in this paper. The major technical achievements during the high growth period from 1945 to 1963 included: the use of fire- refined anodes; the introduction of newly-developed rectifiers; the introduction of lead-lined or vinyl-lined concrete cells; improvements in the electrolyte heating system; application of improved anti-corrosion materials and the introduction of heat-insulating surface coverings. In 2018, Japan’s refined copper production totaled 1,595,000 tonnes of copper, with Japan ranking third in the world after China and Chile. INTRODUCTION In 2018, Japan’s refined copper production totalled 1,595,000 tonnes of copper and Japan ranked third in the world for refined copper after China and Chile (Wood Mackenzie, 2019). There are now eight copper refineries in Japan which provide Japan’s production of refined copper. These plants are listed in Table 1 (Wood Mackenzie, 2019), also showing the production trend since 2013; in general, production over this period has been relatively steady. The Toyo plant is now the 7th largest copper refinery in the world after several large plants as rated by capacity in China, Russia and India (ICSG, 2019).

Jan 1, 2019

By G. Bonnivard

"A complete laboratory process for the treatment of lateritic ores containing a high proportion of iron, as well as chrome and alumina, has been established. The ores treated originate from the tropical zones and result from superficial climatic alteration. According to recent estimates, the known reserves of such ores reach many billions of tons, thus representing huge potential reserves for the elements they contain.The process used is based on the alkaline roasting of pelletized ore in the presence of sodium carbonate. This treatment results in the separate recovery of pellets of upgraded iron ore, pure chrome oxide and hydrated alumina. The research described in the paper aims at determining the best experimental conditions for obtaining the highest extraction of the required oxide from this type of ore."

Jan 1, 1967

By Qing-hua Tian, Li-then Cheng, Xue-yi Guo

In order to recycle valuable metals from silver separated residue, a novel method using alkaline smelting at low temperature was proposed. The main factors affecting the main metal recovery such as the smelting temperature, smelting time, liquid-to-solid ratio and alkali addition were investigated comprehensively. The behavior of the main metal elements, such as Pb, Sn, Sb and Bi in silver separated residue was also discussed. The results indicated that amphoteric metals such as Pb and Sn can be smelted into the melt, while other metal elements, such as Sb and Bi were left in the residue.

Jan 1, 2011

By Suzie Poulin, N. Geoffroy, G. P. Demopoulos

Most metallurgical industries generate toxic waste that must be treated prior to being released to the environment. However, in a lot of cases, the waste materials are poorly characterized or the analytical results are not well interpreted. These shortcomings often result in the development of inefficient industrial procedures, thus causing economic waste and difficulty meeting environmental regulations. Fortunately, a wide range of analytical techniques are available to guide researchers and engineers into making sound process development decisions. In this work, an industrial selenium and mercury removal process is used as an example to illustrate the application of X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) coupled with Energy-dispersive X-ray spectroscopy (EDX) and powder X-ray diffraction (PXRD) on solid waste. Furthermore, samples of analytical results are presented and interpreted and the modifications to the industrial process that resulted are explained. Finally, a brief description of the advantages and limitations of the aforementioned analytical techniques is given with an emphasis on industrial solid waste material.

Jan 1, 2011

By R. ZapataN.

"In the following report, Altonorte Smelter owned by Xstrata will explain its experience with its denominated furnace called ""Continuous Altonorte Reactor"" since started up in March 2002. The Reactor is the main and only smelting furnace since the operation of Reverb Furnace was stopped (15 days after the start up of the Reactor) and it can be operate with dry concentrate for injection by tuyere and wet concentrated via Garr Gun when the injection system fails. From the started up of the Reactor, three operational campaigns have been carried out where in each one they have been increased their smelting throughput and availability. The flexibility reached by the technology bath smelting has allowed a high level of smelting of concentrate and revert materials. The high availability of the Reactor and overcoming problems that were considered of high complexity like the extraction of white metal and slag, refractory campaign, etc. has allowed the Altonorte smelter to project to smelting 1,200,000 tonnes per year with its only Reactor in next year."

Jan 1, 2007

By A. Osouli, B. Moradi Bajestani

"Increase in permeability of rock mass is vital for both petroleum and geothermal applications. Hydraulic fracturing is a common method to create and increase the permeability for production. Due to the complexity of fracture propagation in a naturally fractured medium, understanding the interaction between hydraulic fracture (HF) and natural fracture (NF) is of great importance to optimize the fracturing process. The possibility of interaction between HF and NF is partly a function of orientation. Various scenarios are predictable for hydraulic fracture regarding the intersection with NF such as being arrested by NF, crossing NF or crossing the fissure while injecting water into it. Different parameters such as geomechanical and geometrical properties of surrounding rock mass, the operational parameters such as injection rate and the angle between created hydraulic fracture and natural fracture (approach angle) can affect the result of hydraulic fracture and natural fracture intersection. In this paper, using a series of flow-coupled Distinct Fracture Network (DFN) simulations, hydraulic fractures were analyzed to investigate the influence of the aforementioned parameters on the hydraulic fracture propagating. Results show that the most significant parameters affecting the interaction of natural and hydraulic fracture are orientation of the intersection as well as injection rate. The interaction and fracture propagation in NF and HF intersections are also studied and discussed in detail.INTRODUCTIONThe hydraulic fracture technology has substantially changed the oil, gas and geothermal industries. With the help of this technology, extraction of fossil resources from tight shale reservoirs will be economical, feasible and sustainable. Due to presence of massive oil and gas trapped in these reservoirs, this technology has been the center of attention for the past 40 years (King, 2012). Hydraulic fracturing is the process in which high pressure water is pumped into shale unconventional reservoirs with low to ultralow permeabilities. With this process paths are created in these mediums for delivering oil and gas to horizontal wellbore and increase the surrounding rock medium permeability. Economical and sustainable stimulation of these tight reservoirs is highly dependable on our understanding in regard to fracture propagation in the highly complex rock medium. Hydraulic fracturing process in rock mediums with preexisting natural fractures is more complex because of the high possibility of Hydraulic Fracture (HF) being arrested or deviated by Natural Fracture (NF). Also, HF and NF intersection can influence the required pumping pressure, injection rate, the outcome of horizontal wellbore and the affected geological underground zones. Since the 1950s, numerous studies have been conducted to predict and plan fracture propagation with the help of modeling and simulation methods. Having a thorough and accurate prediction of fracturing process will not only prevent stimulation of unwanted geological zones or pollution of aquifers, but also will improve the efficiency of the fracturing process. Previously, several studies have been conducted in order to investigate and analyze the interaction of hydraulic fracture and natural fracture (Cottrell, Hosseinpour, & Dershowitz, 2013; Doe, Lacazette, Dershowitz, & Knitter, 2013; Shakib, 2013; Zhang & Jeffrey, 2006)."

Jan 1, 2015

By Jose Alberto Gonzalez, Said Sharif Mahboob, Jeffrey L. Shepherd

"During the industrial electrowinning of zinc, uneven growth can cause short-circuits and make the deposits more sensitive to the presence of impurities that can significantly impact current efficiency. To produce levelled zinc deposits, additives such as glue, licorice and sodium silicate are often added to the electrolyte. Even in the presence of additives, uneven zinc growth still takes place because of the combination of hydrodynamic and electrolysis conditions in the cell house. Recent advancements in imaging spectroscopy and scaling analysis have opened an avenue to further study the effects of additives on zinc growth morphology. In this study, Atomic Force Microscopy (AFM) and scaling analysis have been used to monitor zinc growth characteristics including roughness, periodicity, aspect ratios and growth mechanisms as a function of electrolyte composition as well as deposition time. Zinc was electrodeposited from an industrial electrolyte containing a host of additives onto an aluminum cathode with a platinum wire serving as the anode. AFM images of the samples were collected to obtain 3D topographical information on which scaling analysis was performed to extract details on root-mean-squared (rms) roughness, periodicity (grain size), aspect ratio of surface features and growth mechanism. This analysis provided information on the mechanism by which the previously mentioned variables can impact short term growth and also provided a prediction of expected growth at long deposition times.INTRODUCTIONElectrowinning is one of the final stages in the industrial production of zinc metal. It is during this process where dissolved zinc ions undergo electro-reduction from an acidic electrolyte onto an aluminum cathode and are later recovered by stripping the zinc metal from the substrate. However, due to the nature of zinc growth as well as the various operating conditions, zinc deposition may occur unevenly, sometimes causing short-circuits that can cause electrode damage and reduced zinc production."

Jan 1, 2016

By G. M. Ross, J. A. Scott, C. A. Laamanen, H. Shang

"Indirect recovery and use of waste heat contained in smelter off-gas is proposed to expand regions available for year-round, on-site production of micro-algae–sourced biodiesel, a fuel that could be used in underground machinery. A dynamic model of an off-gas heat exchanger describes capture and distribution of heat into open, external, rectangular micro-algae ponds. Smelter off-gas contains sufficient energy to maintain large-scale micro-algae cultivation pond temperatures above 15°C, even with winter ambient temperatures below –15°C. Results highlight opportunities that could lie in tapping these heat resources to produce renewable biofuels on-site and sequester CO2 while leaving the industrial process unaffected.RÉSUMÉ On propose la récupération et l’utilisation indirectes de la chaleur résiduelle contenue dans les dégagements gazeux des fonderies pour développer les régions se prêtant à une production toute l’année durant et sur place de biodiesel à partir de micro-algues, carburant dont on pourrait se servir pour le matériel d’exploitation souterraine. Un modèle dynamique d’échangeur de chaleur contenue dans les dégagements gazeux décrit le captage et la distribution de la chaleur dans des bassins rectangulaires ouverts de micro-algues en extérieur. Les dégagements gazeux des fonderies contiennent suffisamment d’énergie pour maintenir les températures des grands bassins de culture de micro-algues au-delà de 15°C, même avec des températures ambiantes en hiver inférieures à –15°C. Ces résultats soulignent les possibilités que pourrait offrir l’exploitation de ces sources de chaleur pour la production de biocarburants renouvelables sur place et pour la séquestration de CO2 sans que cela n’ait d’incidence sur le procédé industriel.INTRODUCTIONMicro-algae that grow in water can efficiently convertsolar energy and carbon dioxide into biomass. This biomass can be up to 50% oils (lipids), which can be extracted and converted into biodiesel through transesterification (Demirbas, 2008). Compared to terrestrial plants that produce similar oils (e.g., jatropha, soybean, and rapeseed), micro-algae represent an order of magnitude increase in areal productivity, do not require arable land, and can be continuously harvested (Rawat, Ranjith Kumar, Mutanda, & Bux, 2013). The potential advantages through the production of biodiesel from micro-algae also include sequestration of carbon dioxide, reduced reliance on fossil fuels, and the co-production of other value-added bioproducts."

Jan 1, 2017