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By T. E. W. Nind

"A short description of the chamber lift method for producing oil wells is followed by some comments on compressor requirements and gas utilization. A quantitative analysis of the process is presented and, based on this analysis, criteria are suggested for selecting wells for which this type of lift might be suitable. The analysis leads to the conclusions that chamber lift is an efficient producing mechanism for wells having very low productivity indices (say about 0.05 bbl/d/ p.s.i. or less), but that for such wells optimum utilization of injection gas cannot be attained. It is suggested that the gas injection time per cycle should be kept as low as possible, compatible with a small oil fallback volume, and that the cycle frequency should be in the range of 20-40 cycles/ day. For wells with productivity indices of 0.2 bbl/d/p.s.i. or higher, chamber lift is relatively inefficient; how-ever, if well allowables are low it may offer an attractive, low cost, alternative to gas lift or pumping."

Jan 1, 1960

By M. S. Badollet, N. W. Edgerton

"A study of the physical properties of long grades of asbestos fibers imported into the United States during the past eight years has disclosed information that will contribute materially to effective selection and use of fibers for electrical products. The study embraced fiber lengths, volume resistivity under three different conditions, total iron by chemical analysis, magnetic rating, conductivity of an aqueous ex-tract and its sodium chloride equivalent.The fibers examined included chrysotiles from Rhodesia, British Columbia, and Barberton area; marlime from Bechuanaland and Province of Quebec; amosite and crocidolites from Africa and Australia; and anthophyllites from Mozambique and from Georgia in the United States. Volume resistivity values provide a relative basis for estimating the electrical performance of end products; magnetic rating -an estimate of the quantity of iron compounds present in excess of those in the asbestos structure; conductivity of an aqueous extract; and an estimate of the ionizable impurities in fibers.Tests of these factors yield in-formation, not heretofore generally known, which may serve as a guide in the evaluation of asbestos fibers for electrical products."

Jan 1, 1960

By Robert P. Harrison, Marie-Christine Patoinel, Kristian E. Waters

This paper describes a collaboration between McGill University and Hatch Ltd. to expose undergraduate students to real-world industrial projects. As part of the final-year design course, the students receive a detailed lecture on Scale-Up of New Technologies', including seven case studies drawn from over fifty years of full-scale industrial projects. The students are taught the basic concepts of scale-up, including the limits of pure theory and the need for empiricism. Insights from real scale-up failures and successes are fictionalized as Projects A, B, C, etc. The students are then asked to identify the guiding principles that can be distilled from these case studies.

Jan 1, 2011

By J. E. Danoczi

ABSTRACT A diamond processing plant is being designed for the Star–Orion South diamond project in central Saskatchewan. Key to the plant is diamond liberation, which occurs in the comminution section and is the process of breaking up kimberlite rock as gently as possible to minimize diamond damage, particularly in larger, high-value diamonds. Kimberlite from the crater area of a volcanic pipe is generally softer than kimberlite from the diatreme zone. Softer kimberlite, comprising the majority of Star– Orion South deposits, can be readily broken up using abrasion and attrition by autogenous grinding mills, the preferred comminution method for minimizing diamond damage.

Jan 1, 2013

By Jochen Petersen, Jean-Paul Franzidis, Allan Nesbitt

This study presents a method for the determination of intra-particle diffusivities in ion-exchange resins for the purposes of evaluating the state of resin degradation during service. The method uses a zero length column (ZLC) in a closed circuit with variable speed pump and reservoir. The intra-particle diffusion is determined from absorption data by using the Nernst-Plank approximation along with the ‘mass transfer factor’ - which is a product of the mass transfer coefficient (kf )and the concentration of the adsorbing ion in the liquid at the surface of the resin - in a computer algorithm fitting simulated curves to experimental data.. Through this approach the changed intra-particle diffusivity, of a gel-type acid resin, over a 1000 loading and elution cycles, is shown.

Jan 1, 2014

By S. Vongpaisal, T. R. Yu

"A set of new blast damage criteria has been developed, with special reference to blasthole mining operations, for assessing damage by incorporating the vibration level, rock properties, site characteristics and the effects of ground support systems. The main objective of this work was to provide a database with reasonable accuracy for use in optimizing blast design, numerical analysis and ground control expert system module development.The new damage criteria allow one to estimate the degree of damage to rock structures in terms of a dimensionless parameter defined as Blast Damage Index (BDI). This allows for the description of blast damage in a unified form, and facilitates the development of codes for numerical modelling to express the degree of blast damage universally. A number of field investigations from several stope production and slot opening blasts at a large underground base metal mine were carried out to verify the developed index. The results show a good correlation between the observed damage and the type of damage predicted from the BDI values.Practical measures are also provided for minimizing blast damage in large underground blasthole mining operations"

Jan 1, 1996

By James R. Lang

The Xietongmen deposit is located 350 km west of Lhasa, Tibet. It is a new, high-grade porphyry copper-gold discovery and the first deposit to be systematically explored by a western company in southern Tibet. In 2005, Continental Minerals Corporation drilled 21,332 m of core in 63 holes and demonstrated excellent lateral and vertical continuity of high-grade copper-gold mineralization over an area 750 m by up to 350 m in size which remains open in all lateral directions. Drill intersections repeatedly yield grades >1% Cu equivalent (based on gold and copper prices) and include 308.5 m at 0.87% Cu and 1.25 g/T Au (1.60 CuEQ%), and 315.6 metres at 0.61% Cu and 1.11 g/T Au (1.26 CuEQ%). Extensive drilling in 2006 will expand and delineate the deposit, and metallurgical, engineering, environmental and socio-economic evaluations will begin. Xietongmen is hosted by volcanic and intrusive rocks of the Gangdese belt, a magmatic arc active between 120 and 30 Ma along the southern margin of Eurasia. Pervasive alteration is dominated by a well-mineralized K-feldspar and biotite assemblage, and by a more peripheral sericitic assemblage also with strong chalcopyrite. Major vein stages include chalcopyrite-bearing quartz, biotite, magnetite and pyrite-pyrrhotite types.

May 1, 2006

By M. S. Badollet

"IntroductionASBESTOS FLOATS may be defined briefly as blends of air-borne particles of fibrous asbestos and dusts produced during the milling stages and collected by Cottrell precipitators, dust sheds, or bag-houses.The various grades of asbestos floats on the market contain fibrous asbestos particles ranging in length from microscopic to approximately 1/4-inch. The fines or dusts present in the floats are from 40 microns to 2 microns or less in cross-section.Airborne asbestos particles are of diverse length because they are collected at numerous places in the mill. There are: (1) dusts removed from dry rock storage bins, (2) dusts removed from rock and fiber screens, (3) particles from the tops of collectors, and (4) fines removed by suction from the processing equipment. Sometimes the airborne particles are kept segregated, so that there is a partial separation by gravity. This is accomplished by a series of dust chambers enclosed in a long, rectangular building. The longest and heaviest particles fall nearest to the air flow entrance, the smallest at a point farthest away and nearest the exit. Sometimes the air from the dust chamber building is passed through a series of bag-houses or electric :precipitators ,to collect the extremely fine particles which normally escape to the atmosphere."

Jan 1, 1952

By James E. Wennen

The through-put and energy efficiency of an autogenous (AG) grinding mill are adversely affected by variability in rock size and rock competency. This applies to both fully autogenous and semi-autogenous (SAG) grinding circuits. In this paper we focus on an approach to overcome the problem of inconsistent mill through-put related to variability in mill feed size and rock competency. The focus is on ores containing hard, competent rock. This approach consists of preparing feed to an autogenous mill that contains 20% coarse media rock and 80% of material crushed to pass 37 mm. Results of pilot-scale testing for two iron-ores will be presented to show that a 10% to 12% reduction in unit energy consumption is possible with prepared feed, compared with feeding the mill with conventional primary crusher discharge.

Jan 1, 2012

By K. W. Edwards

The formulation of a theoretical basis for the evaluation of in-situ coal through the use of geophysical logs is outlined. This involved the development of an approach to the interpretation of resistivity in environments having multiple conductive and non-conductive components. Utilizing this approach and other conventional interpretation techniques, a program was developed yielding accurate determinations of the in-situ percentages of coal, water and ash for the evaluation of coal deposits. Basic information obtained from the CWA program can be utilized in numerous aspects of total mine planning . Some examples of the practical application of this method are included.

Jan 1, 1978

By M. Aushouri, S. H. Mansouri, N. Aminizadeh

A thermo-chemical model of the Peirce-Smith copper converter has been developed to predict the molten temperature. The primary assumption of the model was that all matte, slag and gaseous phases in the converter were in thermal and chemical equilibrium. In this model, the matte components were considered only as copper, iron and sulfur elements. In the slag making stage, all the reacted iron was converted to fayalite. The reaction rate of iron and oxygen in this stage was considered to be constant. The converter temperature was calculated by heat balance over time. The model was validated by a detailed comparison with measured industrial data. A good agreement was obtained. The converter temperature depends on process parameters such as oxygen efficiency and molten emissivity.

Jan 1, 2007

By A. McLean, X. Men

"With high quality sulphide ores diminishing, nickel production from low-grade oxide ores becomes increasingly important and a major concern is the high sulphur level in the resultant ferro-alloy. So, desulphurization of the ferronickel becomes an important consideration. Red mud is a waste product of alumina industry and causes adverse effects on environment. In the present study, experiments were conducted to determine feasibility of using red mud as a major ingredient of refining fluxes for ferronickel desulphurization. In view of their influence on slag-metal separation, contact angle measurements between ferronickel alloy and molten slag made from red mud were also determined. INTRODUCTIONNickel is a very important metal that finds a variety of applications including consumer products, building, automotive and electronics. There are two kinds of ores containing nickel, namely oxide and sulphide ores. Anthony and Flett [1] reported that about 55% of the world’s nickel production originates from sulphide ores while the balance of new nickel is derived from oxide ores. However, oxide ores count for about 70% of the worldwide reserves. Apparently, oxide ores will play a significant role in the production of nickel in the future. Most of nickel produced using oxide ores is from pyrometallurgical processes namely ferronickel smelting or matte smelting. So, we can draw such a conclusion that using nickel oxide ores to produce ferronickel will become more and more important .Before used to make stainless steel or other materials, the ferronickel need pretreatment to remove impurities especially sulphur and phosphorus that will cause negative influence on the properties of steel product. Red mud is a by-product during alumina production. Usually, about 1 to 1.5 tons of red mud will be produced when we get 1 ton of alumina. About 90 million tones of red mud are produced every year in the world [2].Red mud is deemed as a toxic industrial waste which needs treatment before discharge because of alkalinity and chemical and mineralogical properties. Until now, the main means to deal with red mud are to store it in impoundments or dump it in the sea depending on local environment. Nowadays, how to recycle red mud has become a pretty hot topic around the world. The last 40 years have witnessed a lot of patent applications concerning the ways of red mud utilization. However, a little amount of red mud is consumed until now due to the limitations of recycling red mud."

Jan 1, 2012

The Industrial Minerals Milling Section of the Mineral Processing Division has been engaged for the past three years in a study of the separation of minerals, by means of electronic sorting equipment, on the basis of their colour. Considerable knowledge of the subject has been built up. Because the object of this study is application as a means of beneficiation, a number of examples of the separations achieved are presented. Introduction T 0 the mineral collector, the colour of a mineral may be pleasing, even fascinating; to the mineralogist, student or professional, it may also be practical. It serves, to some extent, as a distinguishing feature in many minerals, and helps to fix with reasonable accuracy the identity of a few. It may now become a useful tool of the mineral dresser. The idea of using a difference in colour as a means of separation of one mineral from another is not new. Hand sorting dates back to ancient time. However, the means by which this can be done mechanically was developed only during the past decade. As far as the Mineral Processing Division is concerned, interest dates from March, 1960, when the following item was observed in the

Jan 1, 1965

By G. Capobianco

"The coal industry is an important part of Canada's economy - as an energy source, employer, and generator of export earnings. Coal comprises 71% of our fossil energy and with rapidly advancing handling and burning technology will clearly play a major role in our national energy mix, eventually as synthetic gases and liquids.International coal markets are very competitive and Canada is disadvantaged by long rail hauls to port, and a heavy tax burden. However, high mine productivity has allowed us to increase our markets.Currently, domestic markets are dominated by coal use for electrical generation, a market with significant growth opportunities.Strong growth is expected in export thermal markets, while metallurgical coal demand is projected to show little or no growth in the medium term. IntroductionThe coal industry is a vital part of the Canadian energy scene .• Coal supplies 17% of Canada's energy.• On a per capita basis, Albertans use more energy in the form of coal than they do oil and gas.• The value of Canada's exports of coal last year was equal in value to all the cars we imported from Japan.• Coal is our largest single export to our seco nd largest trading partner, Japan.• The value of coal produced in Canada exceeds the value of any other single mineral produced in thi s country.• In Alberta, the safety record for coal mines is on a par with that of department store clerks.• The coal industry employs about 25% of the total number of people employed in all metal mines in Canada, directly and indirectly accounting for about 50 000 jobs.Coal comprises 71% of Canada' s hydrocarbon energy resources on a crude oil equivalent basis . This is more than double our oil sands resource and dwarfs our conventional crude oil and gas resources (Fig. I). In the short term, coal as a solid fuel plays a significant part in the Canadian energy scene. In the longer term, coal, in the form of electricity and eventually liquids and gases, has a tremendous role to play. In 1986, Canada produced 57.8 million tonnes, slightly down from the record high of 60.8 million tonnes in 1985. Our exports in 1986 were 26.0 million tonnes, a growth of 53% in three years."

Jan 1, 1988

By I. Masters, K. Buban, M. Faris, M. Antonio, M. Collins

"AngloGold Ashanti Brasil, with assistance from Sherritt International Corporation, has recently commissioned a new autoclave for the pressure oxidation of refractory gold feeds at their Corrego do Sítio operation in Brazil. Design of the new plant, including feed acidulation, pressure oxidation, oxidized solids washing and solution neutralization circuits, was based on the results of test work conducted by Sherritt at their pilot plant in Fort Saskatchewan, Alberta. This paper describes the results of the pilot plant study as well as highlights of the design exercise.INTRODUCTIONAngloGold Ashanti Brasil (AGA Brasil) has recently commissioned a refractory gold pressure oxidation plant at the site of the original São Bento operation in Brazil. The design of the São Bento pressure oxidation facility was based on Sherritt technology; Sherritt carried out the original process development test work in the mid-1980s, provided a process design package and detailed specifications for critical pressure oxidation equipment and participated in the training of operators and commissioning of the plant. The São Bento plant was operated between 1986 and 2007, when the original ore body was exhausted (Silva et al., 2004). AGA Brasil purchased the facility from Eldorado Gold in 2008, with the intent of refurbishing the plant to process refractory gold concentrates produced from the nearby Córrego do Sítio mining area.Sherritt International Corporation has a long history in the development and application of commercial pressure oxidation and pressure leaching processes. Sherritt’s development of technology for the pressure oxidation of refractory gold ores and concentrates commenced in the 1980s in collaboration with Homestake for application at the McLaughlin project in California. This was followed by several commercial applications in Canada, Papua New Guinea and Brazil (Berezowsky et al., 1991). More than thirty pilot plant campaigns investigating the pressure oxidation of refractory gold ores or concentrates have been conducted by Sherritt since the 1980s, and projects with Sherritt contributions to the process development studies and/or engineering design account for about half of the commercial plants that have operated to date with this type of process (Collins et al., 2011a; 2011b)."

Jan 1, 2012

By W. R. Hargrave

"Mining OperationsOre will be mined by open pit techniques. Because of the high grade of the deposit and the low strip ratio, mining rates are small relative to most other open pit operations.The ore deposit is located in the valley of the main fork of Red Dog Creek. The bulk of the deposit is located on the southwestern flank of the creek, but mineralization does traverse the creek in both the north and east directions.Erosion has exposed the orebody in a number of locations, and has resulted in oxidation of the mineralization closer to the surface. Although much of this oxide material is very high grade, it leaches readily and, at least in the initial phases of the operation, will be stockpiled and not treated in the concentrator.During construction, 2.3 million mt. (2.5 million st.) of overburden and waste will be stripped from the orebody to expose ore for initial operations. Competent non-mineralized waste will be used to build roads and waste dumps, but the bulk of material removed consists of oxide or ice-rich soils and weathered rock which is not suitable for construction.The annual ore mining rate will be 1.9 million mt. (21. million st.). The strip ratio will start off at 1.2 to 1, falling to 1.0 to 1 by year 5 and ultimately to 0.8 to 1.Bench heights are set at 7.6 m (25 ft). Pit slopes will vary depending on the material present in the wall. The slope, through competent waste and the sulphide package, was set at 45 degrees. This is flattened to 26 degrees (i.e. 2: 1) through overburden and Upper Kivalina shales. The Kivalina Shales are an ice-rich shale whose carbonate matrix has been leached out and which exhibits little or no strength as it thaws. In addition, a 100 ft containment berm will be left in the wall below overburden and Kivalina."

Jan 1, 1989

By Z. S. Shao, X. Z. Li

"Sub-critical crack growth plays an important role in long-term creep failure in brittle rock. Based on micromechanics established by using relationship between micromechanical wing crack growth model and macroscopic strain, and comparing theoretical model with testing results, a method, which applies the theory to real rock, is suggested in this paper. Using this method, properties of creep, damage and progressive failure in brittle rock are investigated. Effects of stress state on creep failure time and steady-state creep rate are analyzed and graphically presented. The results are helpful to support structure design and service life evaluation of underground structures with high geostatic stresses. INTRODUCTIONDuring the long-term operation in underground space with brittle surrounding rock, due to chemical action between pore water and rock, the failure of rock often occurs at stresses below its short-term failure strength, which brings serious effect on the long-term stability of underground structure. Thus, the long-term strength of brittle rock attracted wide interests of scholars around the world. The static fatigue limit was predicted by exponential function that is derived from abundant experiment data of stress level and failure time(Schmidtke & Lajtai, 1985), and similar result by relationship between stress state and failure time was also suggested (Lau & Chandler, 2004; Aubertin et al., 2000; Sangha & Dhir, 1972). According to relationship between steady creep rate and stress state during creep, a critical stress that transforms steady-state creep to accelerated creep was studied and the long-term strength was suggested (Tsai et al., 2008; Ma & Daemen, 2006; Lajtai et al., 1991). Based on the results of experiment in compression, the long-term strength of rock was defined by stress at volume strain reversal. When applied stresses are larger than the long-term strength, the microcracks in the rock will grow constantly, damage of rock will increase and failure of rock will occur finally (Chandler, 2013; Bieniawski, 1967; Brace et al., 1966)."

Jan 1, 2015

By ANNE FUZESY

Soluble potassium salts in bedded underground salt deposits supply most of The world demand for potassium f or agricultural and industrial use. The potassium salts, sylvite and carnallite, were f irs, noted in drillcores in southern Saskatchewan during The search for oil and gas in ihe early /940s. Problems in shafi sinking beset pioneering potash companies, however, and cominuous production did no, begin uniil 1962. Powsh deposits in southern Saskatchewan occur within ihe uppermost 60 111 of the Middle Devonian Prairie Evaporite a, depths in excess of 900 m. Four groups of po/ash-bearing haliie beds have been distinguished: the Esierha-::,y, White Bear, Belle Plaine and Paiience Lake members. Powsh deposiis extend a jell' kilomeires into Manitoba and south imo orth Dakoia and non heasiern Moniana. Individual potash-rich beds are extensive and consistent in grade and Th ickness. Local th ickening occurs where carnallite is the dominani poiash mineral. Th e preferred ore, sy lviniie, is a clean mixiure of sylvite and haliie. Carnalliie and insolubles are avoided wherever possible because of Their detrimenwl effects on mine stability, grade and refining. Sy lvin ite is exTracted by underground mining or brought TO swjace as brine in solution mining. Poiash is separaiedfrom halite byfloiation or sequential crystallization. The refined produci, potassium chloride, is employed as a fertilizer ingredient as well as in chemical and other industrial capaciiies. The ten poiash mines of Wesiern Canada all are in Saskatchewan and account for aboui 25 per cem of world production. Faciliiies are being expanded, and a new mine and refinery was planned for ihe Breden bury area. Deposiis in Manitoba also were being evaluaied.

Jan 1, 1984

By D. M. Muir

Many plants produce iron(II)/(III) waste liquors which must be treated by neutralisation and precipitation to remove the iron. Iron can be precipitated as crystalline goethite or jarosite by controlled oxidation at low pH and as magnetite by controlled oxidation at high pH, but only at elevated temperatures (>70°C). This study focuses on the characterisation and settling properties of the iron oxides produced at ambient temperatures using various neutralising agents in order to improve the performance of thickeners. It was found that two-stage addition of caustic to FeC12 solutions produced a fast settling material characterised by Mossbauer spectroscopy and XRD as maghemite and magnetite. However, lime and magnesia additions resulted in more ferrihydrite formation and much lower settling rates because of the enhanced oxidation of Fe(II) by air. Settling rates decreased significantly as the proportion of Fe(III) to Fe(II) in the liquor increased. The mechanism of iron oxide precipitation is discussed together with some reasons for the different behaviour of the neutralising agents.

Jan 1, 2006

By J. Oré

An alternative method for dewatering slurry (tailings) is the use of geocontainers (MacTubes). The practical application of this work was carried out in the concentrator plant of the Raura Mining Company, located in the occidental mountain between Huánuco and Lima in Peru?s central highland. For the development of the research, the MATLAB R2012a software MGeST (v. 1.0) was used (Slurry Geocontainer Maccaferri Treatment). MGeST is used for sizing MacTubes, which allows determination of the most important design parameters, such as height (H), filling residual pressure (P1O ), strength of geosynthetic (T), and dehydration height. Compared with GeoCoPS v. 3.0, there is a maximum difference of 3% between the results obtained. The tailing to be treated in the MacTube have a specific weight of 11.62 kN/m3. After several tests it was determined that a MacTube of an apparent opening size of 0.22 mm was required for this specific weight.

Aug 1, 2013