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By Tong Qin, Jinxia Zhang, Fusheng Niu, Limei Bai

"The interaction between a deformable bubble and a rigid particle in viscous liquids under microgravity conditions is studied by direct numerical simulation via an Arbitrary-Lagrangian-Eulerian (ALE) method. Due to the microgravity, the bubble will stay as a sphere in the fluid without external forces and its deformation is caused by the moving particle. In this study we assume the flow field is axisymmetric and the motion of the gas inside the bubble is neglected. The particle equations and the Navier-Stokes equations for the fluid are solved in a unified finite element framework. The particle obtains an impact velocity by an external force and the impact velocity is varied over a wide range. A ‘critical time scale’ T0 was identified for the interaction process. For successful contacts between particle and bubble, the time scale of their relative motion must be less than T0.INTRODUCTIONThe particle-bubble interaction is an important process in many applied industrial domains such as water treatment, froth flotation and liquid steel purification. It is a complex three phase process in that it embraces many research areas: fluid hydrodynamics, interfacial forces, particle and bubble behaviour and solution chemistry.Derjaguin and Dukhin(1961) clarified the particle-bubble interaction by introducing three-zone model for small and medium size particles. When the particle is far away from the bubble surface, the hydrodynamic forces are dominant. The particle is driven toward the bubble surface by the particle inertial and gravity. This region is regarded as Zone 1 and the interaction in this zone is a collision subprocess. As the particle gets close to the bubble, it exits a zone where the liquid flow around the bubble surface creates a tangential stream from the upper surface of the bubble toward the rear of the bubble. This is Zone 2 which is called the diffusiophoretic zone. In Zone 3, the particle is very closed to the bubble, surface forces like van der Waals, electrostatic and structural forces are considered. Contrast to Zone 1, Zone3 can be regarded as an attachment subprocess."

Jan 1, 2016

By T. Fekete, D. L. Flocks, R. T. Hart

The plugging effect of bacteria was investigated by injecting various concentrations of dead bacteria cells though sandstone cores. Pressure profiles along the cores were recorded periodically during the injection cycles. The plugging effect was analyzed using a plot of the ratio of reduced permeabilities to the initial permeability versus input volume. Results indicated that Tock permeability has little effect on plugging, but that the concentration of bacteria in the injection water has a significant effect on plugging characteristics. The pressure profile curves showed that bacteria penetrated several inches through the core but that the greater portion of the bacteria accumulated at the in-put end of the core.

Jan 1, 1960

By D. Want

In titanium-lined autoclave design the most critical point of its mechanical reliability is its titanium batten strips present at the circumferential and longitudinal barrel-weld seams. Recently an Australian Company, W.E. Smith Hudson (WESH) P/L, has developed a fully flush batten strip and is building autoclaves with this design. Significant research and development has been performed in the process. In this presentation, design aspects of these batten strips are presented that cover topics such as residual-stress magnitudes during fabrication, affect of preheat during batten-strip welding and residual stress in respect to fatigue life. There has been little research done regarding the affects of residual batten stress in relation to fatigue life. Considerations of this 'grey' area of design will be discussed based on the author's research data and finite element analysis.

Jan 1, 2005

By A. J. Petrina

"At Craigmont Mines Limited, Merritt, B.C., tests were begun in March, 1965 to evaluate the use of shotcrete as a method of ground support m development headings; previously, ail drifts had. required support, which was accomplished mainly by timber and occasionally by the use of rockbolts. The tests demonstrated conclusively the effectiveness of shotcrete for supporting Craigmont's ground. Gradually, the use of timber for ground support was virtually eliminated in favour of shotcrete. This paper describes the equipment used, the operation of the equipment, pertinent cast data and opera ting details. Also discussed are other uses developed for the shot-creting equipment, the use of reinforcing bar rockbolts, and a method used at Craigmont for lining long vertical ore passes with steel plate and concrete as part of the raising cycle."

Jan 1, 1968

By T. T. Tigert

INTRODUCTION THE PURPOSE of this article on methane is to present the simple basic facts of the characteristics, detection, occurrence, and control of this natural gas in metal mines, so that operators and .safety men may deal with it with some degree of confidence. Fortunately, although methane has been noted at many metal mines throughout Canada, the occurrences usually are small flows of short duration, and the ignitions experienced have, in most cases, had minor consequences. However, methane does present a hazard that can be of serious proportions, and ?any complacent attitude toward this gas that might exist in the minds .of people engaged in underground mining operations should be dispelled when it is ,pointed out that, in Ontario alone, ignitions of this gas have resulted in at least four fatalities, and eight men seriously injured and burned, during the past three years. lt is well-known that liberation of methane can and does .occur suddenly, often in mines where no gas has been found before, and that many ignitions and explosions have occurred in so called non-gassy mines. In view of this, it is apparent that no mine can, with any degree of certainty, be classified as non-gassy. CHARACTERISTICS OF METHANIZ The characteristics of natural gas encountered in most of the Ontario mines indicate that methane is the chief constituent. Methane (CH4), commonly termed 'marsh gas', and by the coal miner 'firedamp', is a colourless, odourless, and non-poisonous gas considerably lighter than air, and is the explosive gas frequently found in coal mines. Its physiological effects, closely resemble those resulting from nitrogen.

Jan 1, 1951

By J. Hedderson, J. Starkey, S. Reeves, B. Hilscher

"As ore sorting becomes more common, it is important to quantify its impact on comminution circuits in order to precisely predict its effect on throughput, grind, and mill operating conditions. Since sulphides and other valuable minerals are often softer then the surrounding waste rock, the ore kept by a sorting system is typically softer than the average ore. In order to accurately forecast production, new measurements of hardness need to be performed on the new concentrated mill feed. This paper proposes a methodology to examine this effect quantitatively at an early stage of project development using the SAGDesign test.INTRODUCTION The application of ore sorting in the mining industry is one of the most promising recent technologies with the potential to cause step change in the way concentrators are designed. Most typically, ore sorters are used to sort a given ore flow for grade, either to reject waste from the mill feed, or rescue ore from the waste pile. Ore sorting technologies have been successfully applied at many mining properties in various forms and while the technology has reached or is reaching maturity in other industries, it is still in development in the mining sector. As a result, there is not yet a general consensus on the considerations that need to be made when designing a plant with ore sorting from a feasibility level above and beyond what is commonly performed as best practice. This paper will discuss those considerations and propose a methodology for integrating ore sorting into a comminution circuit at the design phase. Due to the linearly additive nature of the SAGDesign Test results, a “hardness balance” can be developed to estimate the ore hardness which would be measured in any sorting mass split using only two data points. This will allow a design engineer to make more informed decisions as to the most appropriate mass split to select in relation to the incurred operating costs and grinding circuit sizing."

Jan 1, 2019

By D. R. Murray

A four-year study was carried out to determine the ability of coniferous trees to aid in the reclamation of uranium tailings at Elliot Lake. Five species were planted: white cedar, white spruce, jack pine, scotch pine and red pine. More than 570 bare-root, two-year-old seedlings were planted on bare tailings and in areas of established grasses. A further division was made between areas of coarse and fine tailings. Over-all survival and growth of the trees has been far below expectations based on previous experience with several varieties of grasses. The criteria for assessment have been per cent survival and yearly growth as determined by plant height. Pine was superior, with 68% survival when planted in bare coarse tailings, 45% for vegetated coarse tailings and 34% for vegetated fine tailings. Cedar had the worst survival rates at 49%, 14% and 7% respectively. No species survived on bare fine tailings. The survival and growth of the coniferous trees have been related to species, environmental conditions and tailings properties.

Jan 1, 1978

By G. M. Behrend

"AbstractMeasurement and control systems in minerals processing plants are usually well thought out and designed. The criteria and design parameters have been interpreted correctly.However, these systems often fail to perform satisfactorily or break down altogether as a result of in-plant conditions which are unpredictable and over which the instrument systems designer has no direct control. The foresight necessary to anticipate the problems and allow for them in the systems design can only be generated by experience.This paper lists the most common of these problems and offers practical methods for their solution. It then follows with an analysis of instrument installation practices and comments on special points that need watching.Finally, instrument maintenance is discussed with a view to achieving good maintenance at the best possible economy.Good MeasurementGeneralTHE MINES and mineral processing plants of the nineteen seventies, after decades of sensible caution, have now committed themselves to extensive automatic control. X-ray analyzers are freely specified. Sample acquisition systems are efficient and automated, computers are reliable and relatively cheap, and computer control systems in conjunction with the new analyzers are operating in a good many plants and are proving to be profitable.The sight of shift foremen and floor operators assembled in front of a TV-tube and taking a computer data display as gospel truth is quite common now, and yet was quite unthinkable only ten years ago."

Jan 1, 1977

By Clemens Kuhnert

"Nickelhütte Aue GmbH is specialized in the recycling of waste materials containing non-ferrous metals. We treat nickel, copper, cobalt, vanadium, molybdenum and precious metal containing materials like spent catalysts, ashes, dusts, grindings, liquids, slurries and sludge's as long as they contain one or a combination of the above mentioned metals. In our pyrometallurgical works we produce non-ferrous metal concentrates suitable for further treatment in our hydrometallurgical plant where we refine Ni-, Cu-, Co- and V-chemicals. Our production is based on synergy effects due to the combination of pyro- and hydro-metallurgy. As an example we can mention our heat recovery system and internal recycling of by-products. Furthermore, the use of alternative fuels instead of fossil fuels contributes to the economic and environ-mentally friendly treatment system.INTRODUCTION Nickelhütte Aue GmbH (NHA) can look back on nearly 400 years of tradition as a pyrometallurgical works and recycling company. The existence since its foundation in 1635 as a blue dye works shows responsible and successful action in the past. Therefore, we see highest customer service, minimization of interferences with nature by closing material cycles and maximized health and occupational safety protection by avoiding injuries and diseases, still as our future duties. These duties are evaluated and monitored by an integrated management system that meets the standards of DIN EN ISO 9001, 14001, 50001 and BS OHSAS 18001. We commit ourselves to the observance of all juridical and customized demands. The management and the department managers perceive their model function. We require responsible action from all employees. To protect the continuity of our enterprise, we will also perform in future continuous improvement of products and their quality, as well as steady progress in the areas of environment protection, health protection and industrial safety. Equally the effectiveness and propriety of the management system is checked and developed regularly. In order to obtain the objectives resulting from this policy, our company determines activities and measures by involving all employees."

Jan 1, 2017

By R. A. Brown

RIGHT NOW the Canadian oil business is suffering from growing pains brought on by developments outside our borders. I would like, therefore, to place our industry in perspective for you in two ways. I would like first to describe it briefly and let you see it in relation to the world oil industry. Then I would like to bring it back and place it into perspective against a strictly Canadian background. Naturally, in such a discussion, it is necessary to use a certain amount of statistical material. I'll endeavour, however, to keep it to a minimum. Eleven years ago, before the discovery of Leduc, Alberta could boast of having 21,000,000 barrels of crude oil reserves. Five years ago we had 1,810,000,000 barrels. At year end, 1957, our remaining recoverable reserves totalled more than 3,000,000,000 barrels. In 1957, our potential production in Alberta reached an all-time high of 756,000 barrels a day. Unfortunately, our actual average daily production dropped from 393,000 barrels per day in 1956 to 376,000 barrels per day in 1957. And in 1958, to date, it has dropped sharply to around 300,000 barrels per day.

Jan 1, 1958

By M. Narita, S. Nakayama, M. Fujihara

Hibi Kyodo Smelting Co., Ltd. was founded in 1968 and celebrated its 50th anniversary in 2018. In 1972, we started producing copper cathode with a production capacity of 84 KTPY. Since the company founding, we have undertaken seven expansion projects, and our current copper-cathode production capacity is 290 KTPY. To increase our production efficiency, two tank houses were converted from Conventional process to ISA process in 2006 and 2014. In another investment, we equipped a continuous glue dosing system, which allowed for strict additive-concentration control, yielded quality improvements and reduced the power-consumption rate. Along with an increase in the production of copper cathode, the amount of impurities eluted from the anode increases. To solve this problem, the chelate-resin purification process that was introduced in 1983 was renovated, and impurities could be recovered more efficiently. In this paper, we report various improvements that have been implemented at the refinery since 2000. INTRODUCTION Tamano Smelter and Refinery of Hibi Kyodo Smelting Co., Ltd., founded in 1968, celebrated the 50th anniversary of its founding in 2018. The Tamano Smelter opened its No. 1 tankhouse in 1972, and began operating No. 2 tankhouse in 1984. Thereafter, with continuous production increases and technical improvements, electrolytic copper production was increased from 84 KTPY to 290 KTPY as shown in Figure 1. Table 1 shows the major operating facilities and operation data in 2017.In this paper, details of equipment introduced to continuously dissolve and add glue, various improvements made to the chelate resin process, enhancements made to the crude Ni sulfate process, and another vibrating screen introduced to the copper slime processing flow in accordance with the expansion of copper production capacity since 2000 are reported.

Jan 1, 2019

By G. E. Veins

This paper summarizes an investigation in which beneficiated ilmenite ore was smelted in a continuous, three-phase, 250 kv.a., open-top electric furnace. Minus %. inch ore was smelted, using the standard method. Fine ore, in the order of minus 14 mesh, was smelted in the briquetted form by the open bath method, and in the unagglomerated form by the cold dry-top method. The latter was shown to be superior. The data obtained .are discussed at some length. During the investigation, slag aver-aging 82.5 per cent Ti02 was produced over a period of 87 hours, the maximum being 85 per cent. Such slag should .be particularly attractive for the production of titanium tetrachloride, from which titaniurn metal is produced. The advantages of using paper-mill bark for producing a furnace charge of low bulk density, as required in cold dry-top smelting, were emphasized.

Jan 1, 1957

By J B. Maughan

Gas and oil seeps have been known in Quebec for more than one hundred years. These occur in three main areas which contain sedimentary rocks with a total thickness estimated to vary from 6,000 to 20,000 feet. The strata in these areas are similar in many respects to those in producing areas of southwestern Ontario and the Appalachian basin, and the prospects for finding and developing commercial reserves of oil and gas in Quebec would therefore also appear to be favourable. Little of the exploratory drilling to date has been con-ducted in a systematic manner, and most of the drilling has utilized improper or inadequate equipment. Many wells have also failed to adequately test and fully evaluate the principal zones of interest. Relatively high drilling costs have hindered systematic exploration; however, with improved portable equipment, it is expected that future wells can be drilled with greater efficiency and at less cost. Most of the mineral rights in Quebec are held by the Provincial Government, and acreage can still be leased in large blocks on favourable terms.

Jan 1, 1964

By G. M. Mason

History Due to its strong affinity for oxygen, aluminium as an element was isolated only after many other rarer metals had been prepared and studied. It was just over one hundred years ago that two scientists, Hans Christian Oersted and Friedrich Wohler, produced the first few pellets of aluminium and determined its physical properties. These early investigators used metallic potassium as a reducing agent. Later, St. Claire Deville, by using sodium instead of potassium, improved the yield in the reduction and produced some pounds of aluminium. From a figure of about $110 per pound in 1855, the price had fallen to about $4 per pound by 1886. In that year, a very important discovery was made independently by Charles Martin Hall in Oberlin , Ohio, and Paul . Heroult in France. Stated in its simplest terms, the discovery of Hall and Heroult was that aluminium could be produced by electrolyzing a solution of the oxide in molten cryolite. The application of the Hall-Heroult process made the metal immediately available in commercial quantities and, by 1900, the price had fallen to 23 cents per pound. The growth of the industry in the past fifty years is well known, and is outside the scope of this paper. It is, perhaps, not generally known that aluminium was first produced in Canada at Shawinigan Falls in 1901. Since that time, production has been continuous at one or more smelters in the Province of Quebec. The largest of these smelters, which is also the largest aluminium smelter in the world, is at Arvida, Quebec, on the Saguenay river. A large power potential and access to ocean shipping were the two principal reasons for the establishment of aluminium production facilities in the Saguenay district. It is interesting to note that the aluminium industry, as a large user of power, took an active part in the early industrial development at Niagara Falls and Shawinigan Falls, and is now repeating the process in the Saguenay valley.

Jan 1, 1949

By W. S. Tremaine

When the Hedley Mascot mill was built in 1935, it was designed as a straight flotation plant. The ore to be treated at that time was a gold ore in which the gold was intimately associated with arsenopyrite and pyrrhotite in highly silicified and garnetized limestone gangue. This material was ground to 85 per cent minus 325 mesh in two-stage grinding and floated in standard flotation cells to produce about a 5-ounce concentrate, which was shipped to Tacoma smelter for refining. This arrangement gave us a recovery of about 89 per cent. Test work indicated that the best way to improve this recovery would be to build a cyanide plant to treat our flotation middling. Arrangements for the construction of this plant were finally approved and work on it was started in the spring of 1940. This plant was of the conventional type in which the flotation middlings were thickened, filtered, and then put through the usual cyanide process. Its capacity was 50 tons of middlings per day. This arrangement worked quite satisfactorily and gave us an increase in overall recovery of 4 per cent. Unfortunately, about the time the plant was completed, we developed, and started to ship to the mill, ore that differed entirely from that met with up to that time. Instead of being hard, it was very soft, the orebody from which- it came being much faulted and brecciated. In many sections, the sulphides were oxidized and the breccia was filled in with a very soft, hydrous iron silicate known as chloropal. When this new ore was mixed with the old ore and sent to the mill, the whole operation was disrupted. The chloropal slimed so badly that the classification, flotation circuits, and cyanide plant would not handle it. The difficulty in the cyanide plant was at the head end, where the 10 ft. by 20 ft. thickener and the 8 ft. by 8ft. drum filter would not handle the middlings containing a large percentage of primary slime and chloropal. This material would not thicken to more than 30 per cent solids in the thickener and, when pumped to the filter, would forma very thin, slimy cake. Overall recovery dropped to between 83 and 84 percent and it was quite apparent that some extensive changes would have to be made in our flow-sheet before this ore could be treated successfully.

Jan 1, 1947

By R. L. Bruening, N. E. Izatt, S. R. Izatt

The need for selective metal separations has increased as the mining industry encounters more complex ore bodies and demand for higher performance end products expands. The Molecular Recognition Technology (MRT) process uses highly selective SuperLig® resins to remove desired metals from a variety of solutions in the mining and metals processing and recovery industries. MRT separation processes efficiently produce high purity metal products. In this paper, applications of MRT to metal recovery at mg/L to multiple g/L concentration levels are presented and discussed. Specific examples in the precious metal, nickel, cobalt, zinc, copper, and rare earth industries are given.

Jan 1, 2014

By K. P. Wright

THREE OF the gold mines in the Red Lake Camp operates fluid bed roasters in their milling circuits. The mines are Campbell Red Lake, Cochenour Willans, and Dickenson. The roasters are used for the autogenous roasting of a flotation concentrate for subsequent gold recovery by cyanidation. Cochenour and Dickenson operate single stage reactors, whilst Campbell use a two-stage system. Ore treated by the mines is similar in that the major part of the gold is associated with arsenopyrite. Other sulphides present are pyrite, pyrrhotite, stibnite and sphalerite. Gangue minerals are mainly quartz, with carbonates and talc. Mineralization is, for the most part, extremely fine, and there is intimate association between sulphides and quartz, so much so, th at a picked specimen of apparently massive arsenopyrite will frequently contain as much as 80 per cent gangue. Gold recovery by straight cyanidation on this type of ore would not be higher than 80 per cent and

Jan 1, 1961

By Kyeong Woo Chung, Ho-Sung Yoon, Jyothi Rajesh Kumar, Chul-Joo Kim, Sung-Don Kim

The aim of the present study is to investigate the extraction, separation and recovery of the indivisible metals of dysprosium and neodymium from permanent magnets scrap leach liquor solutions with meaningful recovery. The present experimental development focused on dysprosium separation from neodymium and recovery by suitable mineral acids. Fundamental studies of the effect of time, pH and extractant concentration on the metal separation were conducted followed by proposal of a mechanism for extraction. Process development included generation of McCabe-Thiele diagrams and counter current extraction (CCE) studies. After loaded organic generation from the CCE process, this was followed by scrubbing studies as well final recovery of dysprosium.

Jan 1, 2014

By R. W. Allgood

"THE world-wide shortage of elemental sulphur, which became sharply apparent in 1950, has focused attention on the commercial exploitation of sulphur-bearing materials such as pyritic ores, sour natural gas, and smelter gases. Although there •are no known commercial deposits of elemental sulphur in Canada, there are vast quantities of these sulphur-bearing materials. The International Nickel Company of Canada and Canadian Industries Limited have for many years collaborated in an effort to develop economic processes for the recovery of sulphur from the smelter gas arising from Inco's metallurgical operation at Copper Cliff, Ontario. While sulphuric acid has been •produced at Copper Cliff for over twenty years, recent developments will result in a 60 per cent increase in acid production early in 1952 and, later in the year, in commencement of the operation of the largest single unit ever erected for the manufacture of liquid sulphur dioxide.The purpose of this paper is to discuss •briefly the general factors associated with the recovery of sulphur from the Copper Cliff smelter gases and to describe the sulphuric acid operations and the liquid sulphur dioxide development.Processes for the manufacture of elemental sulphur, liquid sulphur dioxide, and sulphuric acid from sulphur-dioxide-bearing smelter gases are well known and in some cases •highly developed."

Jan 1, 1952

By Fatemeh Pourakbari, Mohammad Reza Yarahmadi, Abbas Sam

Pyrite is the most abundant sulfide gangue mineral in copper porphyry ores. In spite of addition of lime in large quantities to depress pyrite in flotation, considerable amount of this mineral is reported to concentrate, particularly in rougher and scavenger stages. With the Sarcheshmeh pit advancing to a greater depth and reaching to the hypogene zone, the amounts of pyrite and chalcopyrite in the feed are increased. Hence, a reduction in the copper grade and increase in the sulfur content of the concentrate are observed. In this study the effective factors on the pyrite floatability at the circuit flotation was considered at Sarcheshmeh Mine. Mineralization zones in the pit were firstly identified. Then, sampling points were located using GPS system. On the basis of mineralogical composition and morphology, the ore was categorized into five main classes. In this classification the amount of lead and zinc and also pyrite locking with other minerals were analyzed. The study of polished section indicated that inclusion in pyrite was very frequent in all classes, mostly composed of the floatability of pyrite. Flotation tests were performed on the samples of different classes at pH of 11.8 after conditioning time. It was shown that, pyrite floatability was decreased with a decrease in the lead content of the feed samples except for the second class, while for all classes an increase in zinc content contributed to a decrease in pyrite floatability and recovery. It was found that, the lowest pyrite recovery (1.89%) was corresponding to pyrite–molybdenite dominant mineralization with Zn of 0.33% and the highest recovery (86.89%) corresponding to pyrite vein dominant mineralization with Zn equals to 0.9%.

Jan 1, 2016