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By A. J. Kauffman

This study compiles data on the zircon resources of the Pacific Northwest States, Alaska, and California, to determine the productive capability of industrial concerns to make ductile zirconium and hafnium, and to investigate markets for the nonmetallic products of zircon. West coast zircon resources are large but mostly marginal to submarginal. Development of a stable and profitable zircon mining industry on the west coast will depend upon recovery and utilization of the other associated heavy minerals needed by regional and national markets. The west coast has the only completely integrated facility for processing zircon sand to reactor-grade zirconium and hafnium and for making fabricated products from these metals. The future of the zirconium metal industry appears to be good because of increased use of the metal for nuclear propulsion and power-generating plants.

Jan 1, 1965

By A. J. Kauffman

This study compiles data on the zircon resources of the Pacific Northwest States, Alaska, and California, to determine the productive capability of industrial concerns to make ductile zirconium and hafnium, and to investigate markets for the nonmetallic products of zircon. West coast zircon resources are large but mostly marginal to submarginal. Development of a stable and profitable zircon mining industry on the west coast will depend upon recovery and utilization of the other associated heavy minerals needed by regional and national markets. The west coast has the only completely integrated facility for processing zircon sand to reactor-grade zirconium and hafnium and for making fabricated products from these metals. The future of the zirconium metal industry appears to be good because of increased use of the metal for nuclear propulsion and power-generating plants.

Jan 1, 1965

By Yosry A. Attia

One of the most significant advances in Mineral Processing in recent years, is the development of the selective flocculation technology. The technology is primarily aimed at recovering the mineral values from ultrafine ore suspensions. This is achieved by selectively aggregating the mineral particles in question to such size as to enable their effective separation from the suspension. Selective flocculation utilizes the differences in the physical-chemical properties of the various mineral components in the mixed suspension. It is based on the preferential ad- sorption of an organic flocculant on the particular solids to be flocculated, leaving the remainder of the particles in suspension. In order to understand the mechanics of this process, selective flocculation may be divided into four major sub processes; these being: ore slurry dispersion, in which all the particles are stably and uniformly distributed in the suspension with the individual particles being essentially separate; flocculant selective adsorption and floc formation; floc conditioning, which aims at obtaining flocs with desire properties for their subsequent separation and with minimum entrapment of dispersed particles; and floc separation from the suspension. These sub processes will be reviewed later in this article.

Jan 1, 1982

By W. A. SLOAN, G. L. Oldright, J. D. Sullivan, E. K. PRYOR, A. F. HALLET, R. S. Dean, S. L. BROWN, F. S. Wartman, A. J. Thompson

Lack of sufficient publication funds has resulted in the accumulation of considerable unpublished experimental work on copper metallurgy by the Bureau staff . The present report gives extended abstracts of this work , as well as a discussion of the best direction for future efforts . The experimental work reported in this series of papers was done in cooperation with the University of Arizona , Tucson , Ariz . The investigations covered in the third , fifth , and seventh papers were done under the direction of G. L. Oldright and the remainder under the direction of V. H. Gottschalk .

May 1, 1934

By A. Pandey

Over the years, Coal Beneficiation at Tata Steel - West Bokaro has seen varied changes. With increasing R.O.M throughputs & lowering of the concentrate ash, Fine Coal Beneficiation process has thrown up myriad challenges. Development of Synthetic Collector was initiated couple of years back with Technical assistance from NLC Nalco India Ltd. Coal from West Bokaro unit was sent to Nalco?s Naperville (US) research lab for developing Tailor made synthetic collector . After comprehensive lab flotation studies, synthetic collector was developed & recommended for plant evaluation. The lab scale results were very promising in terms of improved separation efficiency & yield at similar ash level. The collector sample received from Nalco research laboratory were revalidated at Nalco Kolkata lab and finally at Tata Steel West Bokaro lab, confirming the promising results. (S.E 25-30 % better than HS Diesel) The key factors playing out for this improvement initiative are a) Scope for improvement in Clean Coal Yield at same or lower ash level coupled with improved Selectivity and Separation Efficiency b) Introduction of a Synthetic Collector with a Green Chemistry and subsequent replacement of H S Diesel, which is highly inflammable with a less inflammable & safer product Trial was conducted at plant scale in two phases and comparative performance of the Collector vis-à-vis Diesel was evaluated across the following Coal Seams of Q- SE (Seam VII, VIII, VI, IX and X). The results generated are very promising and the improvements observed are summarized below. ? Separation efficiency improvement by more than 20% observed. ? Flotation Fines yield increase varied from 0.6- 1.5 % on raw coal basis across different seams. ? Consumption pattern is 20-25 % lower than Diesel. Keywords: synthetic collector, west bokaro, coal beneficiation, HSD

Sep 1, 2012

By H. R. Zhang

In this paper two optional production processes are presented for reasonable utilization of primary sylvinite in Qinghai province, China. The two kinds of products as chlorine-free potash fertilizers; potassium sulphate or potassium magnesium sulphate can be obtained. In the course of potassium sulphate production, using primary sylvinite from Qinghai salt lake as raw material with impurities such as sodium chloride and insoluble in primary sylvinite, it must be prepared by flotation before being converted into potassium sulphate. This final product has found wide use in tobacco industry in China. However, in some cases Chinese farmers would rather buy the fertilizer of potassium magnesium sulphate than high quality of potassium sulphate. With flotation process which is a little different from above mentioned, the potassium magnesium sulphate fertilizer may be produced by washing one of the flotation concentrate presented as picromerite, while another concentrate containing potassium chloride is treated as by-product.

Jan 1, 2014

By F Shi, G Ballantyne, K Runge

There has been minimal innovation in the methods used to process an ore over the last 50 years. Productivity increases have largely resulted in increased equipment size without implementation of parallel improvements in technology. Complex orebodies of the future will need mining operations to adopt new technologies and techniques to make future ore treatment economically viable. Three emerging technologies, namely high voltage pulse (HVP) pretreatment, fine screening and the HydroFloat<sub>TM</sub> coarse particle flotation cell will be presented in this paper and the potential benefits that may result if they are adopted in mineral processing circuits will be outlined. The barriers that must be overcome before they can be adopted by industry with confidence will also be discussed. CITATION: Runge, K, Shi, F and Ballantyne, G, 2018. New technologies that will potentially enable processing of complex orebodies, in Proceedings Complex Orebodies Conference 2018, pp 126–129 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

It is widely accepted that particles stabilize flotation froths and that stable froths result in improved flotation performance. Predicting the effect of particle addition on froth stability is, however, challenging. Furthermore, there is currently no technique that allows the prediction of the effect of different flotation reagents on froth stability, without carrying out froth stability experiments.

By J. C. Nicholson

The "V" system was first introduced by the West Virginia Coal & Coke Company at their No. 9 mine, Norton. Norton is a small mining village on the B. & 0. railway, about seven miles from the town of Elkins. This year, accompanied by G. D. MacDougall, I visited this mine to obtain first-hand information regarding this modem system and to determine its adaptability to conditions in Nova Scotia. The following is a brief account of my observations. The seam that is being worked is known as the Lower Kittaning, which, at this point, has an average thickness of 7 feet. This includes a band of hard clay varying in thickness from 8 to 14 inches, which occurs about 2 feet from the pavement, also 8 inches of inferior coal at the roof. The latter is not recovered, which leaves to be mined about 5 1/2 feet of clean coal. The roof is slate and shale for the first 30 feet, followed by 40 to 60 feet of sandstone; the total cover is from 80 to 250 feet thick. The seam lies very flat, with a dip of only 2 per cent., and, as the dip is toward the main entrance, it' is in favor of the load, also providing natural drainage for any water the mine makes. As the mine is not gassy, and there is no water to be pumped out, one can understand that mining conditions are practically ideal.

Jan 1, 1924

By W. L. Zeigler

THE year 1930 in the Ceur d? Alene district was one of curtailment in production. Many of the small properties were closed entirely and only three large. producers, the Bunker Hill & Sullivan, Hecla, and the Morning mines were left producing at capacity. No innovations in milling were evident, but progress was made in reducing costs as is always necessary in times of low metal prices. One new concentrator was constructed, a 500-ton daily capacity selective flotation plant for, the Jack Waite Mining Co. This mill uses coarse crushing, followed by hand sorting, for both a high-grade ship- ping ore and waste. The remainder of the ore leaving the sorting belt is crushed in a new type Traylor reduction crusher to %-in. size and stored in large capacity mill ore-bins. The grinding is done with ball mills, in closed circuit with a Dorr classifier to 75 per cent - 200 mesh. Minerals Separation 24-in. flotation machines are used both for a lead and a zinc concentrate, with double cleaning in each case. The concentrates are dewatered in Dorr thickeners and filtered on Oliver late-type filters.

Jan 1, 1931

By A. D. Hodges

In May, 1850, the first gold from the Comstock lode was discovered in the sands near the Carson river. It had been washed down by natural agencies, through Gold Caflon, from the decomposed rock of the ledge above. Within a few weeks, the precious metal was traced more than three miles in shallow deposits along the bed of the canon, from the river to the Devil's Gate-—a narrow, rocky cleft, notable to the teamsters of a later day chiefly as the place where " Uncle Jimmy Fair" collected high tolls, and could not reduce the rates, because " this was all he had for the education of his poor children." From 1850 to 1857, a fluctuating band of miners, whose number varied from twenty to two hundred, washed the Gold Canon placers with rockers and long-toms, making four to five dollars a day each until the last-named year, when the deposits were in great measure exhausted. The chief settlement of these miners was at Johntown. During only a third of the year was the water-supply sufficient for their work. The remainder of the time they utilized in desultory prospecting of the hills and in occasional forays for supplies among the Mormons in Carson valley. In 1857, the Grosch brothers discovered the Comstock lode at some point, now unknown, in Gold Hill, but their discovery perished with them. Early in 1858, the " Pioneer Quartz Company," having located several of the small surface-veins around Silver City (whose connection with the main lode has never been definitely shown), built an arrastra, and worked some of their ore; but the returns were so small that they soon abandoned this business. The following winter, James Finney and his partners found gold in place in

Jan 1, 1891

By Richard M. Tinlin

The mining industry needs to assure compliance with the Federal Water Pollution Control Act Amendments of 1972 (Public Law 92-500). Congress has enacted this legislation with the intent of preventing, reducing, and eliminating pollution of the nation' s surface and groundwaters. Recognized sources of pollution such as seepage from tailings ponds, waste dumps, and contaminated effluent from mine dewatering operations pose a serious threat to adjacent groundwaters. In addition, technological innovations being implemented by the industry such as in situ leaching of low grade ore deposits may also lead to ground- water contamination. An adequate monitoring methodology designed to meet the needs of the mining industry is needed. Monitoring and control methodology devised for other man- caused sources of ground- water pollution - e. g., landfills - offer considerable promise for adaptation to the problem. The prediction of deleterious effects on groundwater quality usually requires extensive geohydrological data in addition to a thorough analysis of the mining activity that is underway or projected. If the avail- able data are adequate, mathematical models of surface and groundwater flow can be constructed that will help to predict effects on water quality. Data are inadequate to allow a realistic interpretation of pollution potentials. These data can be supplemented by computer simulation as a method to explore a number of possible environmental effects and also to develop a minimum-cost approach to identifying and gathering the additional necessary supporting data. Incorrect assessment of the important environmental considerations may, in many instances, prove to be the weakest link in analyzing the financial feasibility of a mining operation.

Jan 1, 1973

By A. T. Yu, K. A. Young, Ronald M. Hays, Sanford Terry, D. R. Campbell, J. K. Lovrien, W. L. Price, C. W. Matthews, W. R. van Slyke, S. P. Cole

Storage and transport systems are essential for mineral processing. Section 10 includes systems for storage and transport of dry bulk materials, slurries, and water necessary for operation of mineral pro¬cessing plants. All aspects of these systems are presented, including material characteristics; dry material placement in and reclamation from storage stockpiles and bins; dry material conveyance; hydraulics (liquid flow and pumping); slurry characteristics; slurry storage and reclaim, slurry flow (distributors, launders, and pipes), and pumping; water (primary and secondary process, reclaimed, fire, cooling, and domestic) supply, transport, and storage; equipment selection and sizing; power transmission; controls; and health and safety. The mate¬rials considered include crude ore; process and other water supplies; initial, intermediate; and final in-plant materials; finished materials; and tailings and other waste products. Section 10 is a compilation of practical operating data for engineers, technicians, and plant opera¬tors. For the design of mineral processing plants, including selection and sizing of equipment, the design engineer should consult with equipment manufacturers, suppliers, engineering firms, and plant op¬erators with specialized experience in particular materials handling methods. When unusual conditions are encountered, actual pilot or full scale testing may be required to insure adequate design. Operation of mineral processing plants is dependent on the proper engineering and construction of storage and transport systems for dry bulk materials, slurries, and water. It is obvious that processing plants cannot produce the required quantities of semifinished and finished products unless these material can be transported adequately to, through, within, and from the plant. Costs of storage and transport systems may exceed 50% of the total capital and/or operating costs. Considerable attention must be given to the design, layout, and engineering of these systems. These systems are interrelated with the mineral processing method and it is necessary to determine the best combination of mineral processing method and storage and transport systems. Storage and transport systems perform a major supportive func¬tion to mineral processing. The final selection of these systems depends on the final selection of the processing method and related systems (environmental control, tailings and waste disposal, etc.). The process¬ing method determines the characteristics of materials to be stored and transported; distances, elevations, flow rates for transport; and storage requirements. Flowsheet After selection of the processing method and related systems, a flowsheet must be developed. This flowsheet should indicate produc¬tion rate, percent solids or moisture, and specific gravity for all initial, intermediate, and final products or product flow streams. It also may be necessary to know the size analysis, chemical analysis, abrasiveness, and other physical characteristics of various product flow streams. The flowsheet provides basic information for plant layout, storage requirements, and selection and sizing of process and transport equip¬ment. Storage and transport systems often function improperly be¬ cause of inadequate flowsheet data or process revisions, resulting in improper equipment selection and sizing. Further details on plant design are presented in Section 33. After selection and sizing of process equipment, it is necessary to select the type of material transport equipment to be used for in¬plant materials handling as well as crude ore, tailings, and final prod¬ucts. The storage and/or surge requirements, including capacity and location, then are determined. Storage and/or surge capacity is neces¬sary for leveling production rate fluctuations due to variations in material characteristics; production scheduling; equipment mismatch¬ing, failure, or breakdown; and scheduled maintenance downtime. Variations in ore grindability will cause fluctuations in throughput or production rate for grinding mills and variations in ore grade will cause fluctuations in production rate for concentrating equipment. Variations in material moisture content and percent solids can have serious effects on the capacity of material transport equipment. In some cases, a blending system may be desirable or necessary to reduce variations and to obtain uniform production and/or metallurgy. Storage capacity often is needed because of different production schedules for various phases of the mining and mineral processing complex. As an example, the mine and coarse crushing plant may operate on a one- or two-shift-per-day schedule while the fine crushing plant and concentrator on a three-shift-per-day schedule. This would require storage between the coarse and fine crushing plants. Another example would be load-out storage where unit trains are used to haul concentrate or final products. The concentrator could be operated on a three-shift-per-day schedule while only I to 2 hr may be scheduled for unit train loading. This would require adequate load-out storage so that the concentrator can be operated continuously. Process equipment with mismatched capacities requires storage or surge capacity between the mismatched equipment to achieve oper¬ating efficiency. As an example, the fine crushers may have greater capacity than the rod mills. Storage between the fine crushers and the rod mills permits both the crushers and rod mills to be operated at optimum capacity with the crushers actually operating or running a lesser number of hours per day. Mismatched capacities for process and transport equipment also may require storage or surge capacity. Mismatching of equipment capacities most often occurs because of the difficulty in equipment sizing. Thus, the design engineer must anticipate where in the flowsheet these mismatching capacities are likely to occur while making every effort to assure that equipment is selected and sized properly. Equipment breakdown can cause major operating difficulties and lost production. These breakdowns can be reduced with adequate scheduled maintenance. Lost production due to nonscheduled down¬time caused by equipment breakdown can be reduced further by standby equipment and storage and/or surge capacity ahead of essen¬tial mechanical and electrical equipment. As an example, standby pumps and conveyors often are available as part of the in-plant trans¬port system. Storage and/or surge bins and tanks often serve dual functions, such as dewatering, mixing, and smoothing production rate fluctuations.

Jan 1, 1985

By R. Loj

Katowice Coal Holding (KHW) is one of the largest coal companies in Europe. The company owns five coal mines with a daily output of around 60 000 tons of coal. In the Katowice city area, very good quality steam coal is extracted. The depth of mining varies between 400 and 1100 m and some of the mines rank amongst those most afflicted by methane in the Upper Silesian Coal Basin, with the methane hazard having a significant impact on production and safety. ?Myslowice-Wesola? mine, being a part of the Katowice Coal Holding is characterized by high methane and rockburst hazards. The mine is equipped with a modern surface drainage pumping station. At the mentioned mine, longwall 514 was selected for analysis of its methane emission. The longwall was extracting the thick seam 501 (over 4 m), at a depth of over 900 m, which was subject to high stress and high gas concentration conditions. At a distance of about 50 m above, seam 501 is covered by thin seam 416. The strata between these two seams are sandstone and mudstone layers. In the floor of seam 501, with a thin shale interlayer, is located seam 510, which is the thickest (over 10m) and richest coal seam in the Upper Silesian Coal Basin. In longwall 514 and it?s vicinity, methane was the dominant risk. For this longwall three methods of classical gas drainage were carried out. At first, drainage was undertaken using long boreholes from a cross-cut at level 665 m, located far from the production panel. Later, it was performed using typical boreholes drilled from the ventilation gallery (tail gate road). Finally, it was undertaken using a degassing drift executed in the upper coal seam 416. All of these headings, ie. cross-cut level 665 m, the ventilation road and conveyor road in seam 501 and the degassing drift in seam 416, were equipped with media for drilling and proper drainage pipelines. Due to the high rockburst hazard and some problems with caving, several kinds of de-stressing and torpedo blasts were carried out in both coal seams and roof rocks. The subsequent analysis and experiments allowed the establishment of some general rules for carrying out degassing operations effectively. The effectiveness of a degassing drift was demonstrated. In some instances, the system allowed more than 70% of the total methane released to be captured and fed into pipelines. The aforementioned blasts had a marginal impact on methane emissions and the efficiency of degassing methods. Cyclic drilling and regular switching of boreholes in phase with the mining progress and working face advance were shown to be essential.

Aug 1, 2013

By B. McFadzean, S. Pikinini, C. T. O’ Connor

Sperrylite (PtAs₂) comprises about 21% of the platinum group minerals (PGMs) in the Platreef ore and regularly reports to the tailings due to its poor floatability. Hence, improving its recovery will be of great economic value to the South African PGM industry. The reasons for its poor floatability are not yet clear. This paper seeks to understand the interactions occurring between PtAs₂ and common thiol collectors, viz. potassium normal butyl xanthate (PNBX), sodium normal dibutyl dithiophosphate (SNBDTP) and sodium normal mono butyl dithiocarbamate (SNBDTC). By understanding its interactions with these collectors, it is hypothesised that it will be possible to suggest ligands that may help improve the floatability of sperrylite. Mineral-collector interactions were studied by determining the molar energy of interaction using isothermal titration calorimetry and electrochemical techniques. The hydrophobicity of the mineral before and after adsorption of the collectors was determined by heat of immersion and its flotation response determined by microflotation tests. Microflotation tests using synthetic sperrylite at pH 9 showed low collectorless recovery of 34.8% and after adding the equivalent of one pseudo-monolayer of the PNBX collector, the recovery of 32.5% was obtained. Moreover, the addition of up to three pseudo-monolayers coverage of PNBX did not result in any increase in flotation recovery. A small recovery improvement was noted when synthetic plant water with the ionic strength of 0.0484 mol/L was used, but this did not hold for all collectors, with SNBDTP exhibiting higher recoveries in distilled water. Keywords: Sperrylite; flotation; recovery; adsorption energy; collectors; 2SPW (synthetic plant water)

Jan 1, 2020

By Antony Amberg, Gonzalo Saldías, Romke Kuyvenhoven, Catherine Souza, Heriban Soto, Francisco Soto

"Vizcachitas is an advanced stage copper–molybdenum porphyry deposit, fully owned by Los Andes Copper and located in Central Chile. The property contains an indicated resource of 1,038 million tonnes grading 0.37% Cu and 0.012% Mo, and an inferred resource of 318 million tonnes grading 0.345% Cu and 0.013% Mo (Coffey & Alquimia, 2014). The deposit occurs in the same geological belt as several other giant copper-molybdenum porphyry deposits including Río Blanco-Los Bronces, Los Pelambres-Pachon and El Teniente. In 2018, the original Preliminary Economic Assessment (PEA) study from 2014 was updated; this paper presents the geometallurgical testwork that was performed to support that update. The testwork focused on the metallurgical characterization of 40 DDH samples and the development of a more profound orebody knowledge by relating geological features with metallurgical performance. The scope of work included complete chemical and mineralogical QemSCAN characterization; SAG, ball mill and abrasion testing; complete rougher and cleaner kinetics including locked-cycle-test; environmental ABA and settling tests on rougher tailings. The results show that the ore can be classified as medium-hard, with a hardness that is slightly below the average for large Cu/Mo deposits in the region. A good correlation was found between lithology and breakage characteristics, implying that the specific energy consumption (kWh/t) is well correlated to rock type. The results of the flotation tests were very encouraging and did not show significant variability. An overall Cu recovery of 91% can be expected for the flotation circuit. The use of a relatively coarse primary grind size gave good final recovery and grade for both Cu and Mo, and deserves further attention in future work, as this impacts positively both energy consumption and water recovery.INTRODUCTION Los Andes Copper Ltd. is a Canadian exploration and development company focused on the acquisition, exploration and development of advanced stage copper deposits in Latin America. The company owns 100% of the Vizcachitas project in Chile, the largest copper deposit in the Americas not controlled by the majors. Vizcachitas is a copper-molybdenum porphyry deposit, located 120 km north of Santiago, in an area of very good infrastructure."

Jan 1, 2018

By W. H. Zieman

NORMAN WEISS, Milling Engineer, American Smelting• and Refining Company: The subject of the Forum on Rod and Ball Mill Liners is very fascinating, and there is no end of discussion when operators get together on grinding. However, the hypotheses and suppositions easily outrun the facts, especially when we •consider the inaccuracy of many reported observations. Still surprisingly small is the number of concentrators even reasonably well equipped to measure power consumption of each grinding mill, together with running time, so that data on this tangible factor, at least, can be obtained with precision. While the more elaborate devices of this nature, producing for each 24-hour period the total power consumption, average kilowatt hours per hour, short-term demand chart, instantaneous demand, and print-out, may cost in the neighbourhood of $2,500 per mill and may be difficult to justify, the combination of an ammeter, watthour meter, and running-time meter will cost only a few hundred dollars, so there appears to be little reason not to in-stall them in view of their numerous advantages.

Jan 1, 1959

By J F. H Thompson

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Mineral exploration and mining are challenging businesses. Remote and at times harsh conditions have always made it difficult for exploration, but modern explorers also have to deal with cover, numerous technologies, an explosion of data and critical early community engagement. Mining deals with the reality of moving and breaking thousands of tonnes of rock each day to extract what can be a very minor component of economic value, and, furthermore, society expects that this will be done in a clean and sustainable manner. The exploration and mining challenges appear disparate, but they are intimately related.Although not widely appreciated, both exploration and mining have a long tradition of innovation. Over the last 50 years, major step changes in exploration have resulted from radical advances in our understanding of ore forming processes, new geophysical, geochemical and remote sensing technologies, and new ways to integrate and interrogate data. Over a more extended period, close to 100 years, mining has developed bulk surface and underground methods, selective extraction through flotation and leaching and global positioning system–geographic information system control systems that collectively facilitate mining at a massive scale. And yet, in spite of these successes and the boom that we have enjoyed in the last ten years, the industry is under pressure and the need for innovation and change is paramount.The major drivers for innovation are the need for increased quality in discoveries and mines and the need to interact effectively with communities and jurisdictions such that the benefits of quality mines are recognised and enjoyed widely.We are still making new discoveries around the Pacific Rim and elsewhere, but many argue that the quality – grade and accessibility – of these discoveries is decreasing. The net result is that explorers are delivering resources and reserves for development at lower grades and with higher capital and operating costs than current operations. For mining, the increasing age of many existing operations contributes to increasing costs, which, when combined with decreasing cut-offs and lower grades, also results in declining quality. The combined picture does not look good.Just as the pressure to improve performance and margins in the face of declining inputs increases, we are simultaneously faced with increasing societal demands for improved environmental performance and sustainable practices. This is most apparent at the local, community level, where opposition ultimately leads to delays or even cancellation of new projects. Quality is again the issue – quality of the initial and ongoing engagement and quality of the proposed mine in terms of environmental and economic performance.CITATION:Thompson, J F H, 2015. Exploration and mining – the need for innovation , in Proceedings PACRIM 2015 Congress, pp 45–48 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By F G. Cooke

"This paper describes a medium-sized copper mine's results in making innovations and changing operational practices to combat increasing expenditures due to higher labour and supply costs, extended workings, scarcity of experienced manpower and problems created by deteriorating ground conditions.OPEMISKA COPPER MINES (QUEBEC) LIMITED is located at Chapais in the Chibougamau area, in central eastern Quebec, approximately 300 miles north of Montreal and 150 miles north west of Lake St. John. The latter area, developed by lumbering and farming, has supplied the majority of the employees, who, with training and experience and a desire to work and improve themselves, have become the backbone of the Company's 600 personnel.Opemiska began production in 1954 at a rate of 400 tons per day, using diesel power and road transportation. The rate was progressively increased and, by 1959, with hydro-electric power and rail transportation, the mine had reached its present production rate of 2,000 tons per day. It has produced concentrates containing over 430 million lbs of copper."

Jan 1, 1968

By Norbert Steiner

For the desulfurization of weak SO2 gas streams, Degussa developed a process using dilute H2SO4 solution containing H2O, instead of conventional gas scrubbing with all solid absorbent medium (limestone, MgO). The process is based on fast reaction of H2O, with SO2 yielding H2SO4 up to 70% strength, depending on off-gas temperature. Compared to the conventional systems with typically < 95% efficiency, independent on the raw gas SO2 concentration, residual SO2 concentrations of less than 20 mg/Nm3 can be easily achieved, corresponding to nearly 100% removal. These features render the H2O, process a very attractive, low capital cost technology to retrofit existing conventional desulfurization plants.

Jan 1, 1996