Search Documents

By R. D. Lindsay

Pamour Porcupine Mines, Limited has been actively engaged in the ''Custom Tolling'' of Gold-Bearing materials throughout the past decade. Experience acquired in this area was utilized to design and commission a custom gold milling facility at its operations in Timmins, capable of:(a) Accepting a bulk ore test sample at the rate of 150 t/d for crushing, sampling, and metals analysis;(b) Processing gold-bearing ores at a rated capacity of 150 t/d, to produce a goldbearing sulphide concentrate;(c) Processing free milling gold ores at a rated capacity of 80 t/d for total cyanidation;(d) Cyaniding custom gold flotation concentrates at a rated capacity of 80 t/d; and(e) Processing of complex gold/copper or carbonaceous ores, requiring an impurity flotation concentrate separation stage prior to cyanidation, at a rated capacity of 100 t/d.Items considered in the process design and development included:- various gold ore types available for processing;- flowsheet flexibility required;- sampling strategy as related to head grade determination and metals accounting; and- contract considerations.This paper highlights how these various considerations were used to design Pamour's ''Custom Gold Milling Facility''.

Jan 1, 1987

"Mineral separation by exploiting the differences in mineral or metal specific gravities (sg) has been used since antiquity. In the modern era, this is most commonly seen in the recovery of gold by the use of centrifugal concentrators and the separation of coal (low sg) from waste rock (high sg) using heavy media cyclones and jigs. Other metals, notably oxides of tin and tungsten, are successfully recovered using some combination of jigs, spirals and shaking tables. However, many conventional gravity separation systems are limited to fairly coarse (>1 mm) to medium (>100 micron) particle separations due to the limitations of the gravitational separation forces in conventional equipment.Many of the high specific gravity minerals of interest are friable (e.g. cassiterite, wolframite, etc.) and excessive fines are generated in the grinding/comminution circuits which cannot be recovered with conventional equipment and may be lost directly to the tailings stream. Recent developments in centrifugal gravity separation equipment specifically designed for fine or ultra-fine particle separation and recovery have resulted in heavy mineral particle recoveries as fine as 10-20 microns. Ongoing research work has also identified the benefit of closed-circuit, multi-stage gravity recovery circuits using some combination of centrifugal concentrators and conventional equipment (tables, spirals, flotation, etc.) which can substantially increase overall plant recovery and final concentrate grade.This paper will provide details of the evolution of non-fluidized bed gravity concentrators for high sg mineral recoveries, correlate laboratory scale development work with plant results to confirm scale-up, and show how recent flowsheet developments have contributed to significantly improved plant performance.IntroductionGravity concentration is one of the oldest and most cost effective metal and/or mineral recovery systems, ranging from the classic hand panning of alluvial gold, through to the large scale production of a wide range of metals and minerals, including gold, silver, PGMs, black sands, coal and iron oxides. Conventional gravity recovery systems, comprised of some combination of sluices, spirals, jigs and shaking tables have limited application in fine particle (i.e. <100 microns) recovery, or where there are limited differences in particle specific gravities (sg), e.g. the separation of high sg, high value metal oxides (e.g. those of tin, tantalum or tungsten), from medium sg, lower value metal sulfides such as pyrite and pyrrhotite. These unit operations tend to have limited capacity, and while double and triple turn spirals and multi-deck tables have been developed, extensive floor space is often required in order to process the tonnages incorporated in the modern mineral processing plant."

Jan 1, 2017

By Z. Yang, M. J. Collins, N. E. Tuffrey, R. J. Kalanchey, I. M. Masters

The high elevation of China Western Mining Company (WMC)&apos; s Ganhe refinery, and the high iron content of concentrates produced by the WMC mines, were key factors in the selection of pressure leaching by WMC for their new zinc refinery. This paper describes the results of pressure leaching test work conducted by Sherritt in Fort Saskatchewan with a sample of WMC concentrate from Qinghai Province in China. Results from batch pressure leach tests and a four-day pilot plant campaign are reported. The pilot plant campaign included continuous operation of a two-stage pressure leach circuit, as well as neutralization and iron removal steps, resulting in the production of iron-free zinc sulphate solution. Greater than 98% zinc extraction was achieved in pressure leaching, while producing solution containing about 9 g/L H2SO4 and 2 g/L Fe. Following neutralization and iron removal, the solution contained about 170 g/L Zn and less than 10 mg/L Fe. Overall recovery of sulphur in the zinc concentrate feed to elemental sulphur byproduct was about 85%, while 75 to 80% of the indium in the feed was recoverable from the neutralization residue. The test results highlighted the technical and economic advantages offered by the Sherritt Zinc Pressure Leach Process and provided the required data for the engineering design.

Jan 1, 2008

By K. G. Chipman

THE discussion on Dr. Chipman&apos;s paper, Mapping by the Topographical Survey, centred mainly on the urgent need for aerial photographic reconnaissance of unmapped portions of the country as an initial phase in the provision of suitable topographical maps for use as a guide in geological mapping, prospecting, exploration, and development work in the areas concerned. This, ir was pointed out, would necessitate an expansion of the topographical work of the Bureau of Topography to keep pace with the photographid work and to meet the demand for maps for use by geologists of the Bureau of Geology and others. A resolution requesting Institute Council to make representations to the proper authorities, urging that aerial photography and topographic map-ping be greatly expanded to meet the pressing needs of the situation, was moved by DR. W. F. JAMES and seconded by MR. L. G. SMITH, and carried unanimously. The full text of the resolution appeared on page 221 of the May BULLETIN. Others who spoke in support of the resolution were MESSRS. E. S. MOORE, L. B. ROCHESTER, F. D. SHEPHERD, and W. J. WRIGHT. Dr. Hansen then presented his paper, Mapping by the Geological Survey, discussion on which is summarized below. MR. FRANK EBBUTT(l) spoke of the very valuable service the Geological Survey bas rendered the mineral industry, and indeed the whole nation, in its century of existence, despite the very inadequate financial support it has received. Now, more than ever before, a strong and expanded Geological Survey is essential if the Industry is to continue to prosper. Our known ore reserves are being depleted very rapidly, and we are finding no new orebodies to take their place. As an aid in prospecting and exploration, and also in the development of orebodies when they have been found, we must have geological maps of the vast sections of the country which at present are unmapped or inadequately mapped. The Institute should make every endeavour to have the Geological Survey strengthened so that such maps may be made available as soon as possible.

Jan 1, 1944

By P. C. McLeod

THE GECO OREBODY, located north of lake Superior in the Thunder Bay district of northern&apos; Ontario, was discovered in 1953. Diamond drilling in the following year indicated a 15,000,000-ton ore-body, and production plans were made for the shipment of copper and zinc concentrates in three years. To accomplish this, the Geco Project was initiated. The property was in an undevdoped, inaccessible area, and the project involved the conversion and extension of a logging road to the property, the construction of two railways and seventy miles of hydro transmission line, the erection of a municipality, the building of a plant, and the development of an underground mine to produce 3,300 tons per day. This paper describes some of the methods used in the underground development phase of the Geco Project.

Jan 1, 1958

By Dorothy Walters

As an increase in the number of producers alters fact ors affecting supply, long-term prospects in traditional markets for many minerals weaken. At the same time, conflicts between national and international objectives undermine existing competitive elements in mineral markets and Canadian costs escalate. Such changes may dramatically alter the environment in which the mining industry operates.

Jan 1, 1979

By H. D. Goodfellow, R. A. Elliott

"This paper covers the evolution of large mills and autogenous grinding and compares grinding practice in the iron ore industry with that in the base metal industries. Comments on novel methods of grinding are presented for discussion. Recent developments in the field of classification are briefly reviewed. A systems analysis approach to grinding circuits is discussed. Finally, a point is made for establishing a group within the industry with the purpose of developing a comprehensive evaluation of grinding research and development."

Jan 1, 1971

By C. W. Reno

"THE LORNEX MINING PROJECT is one of several large-tonnage, low-grade operations recently placed in operation in British Columbia. It is located in the Highland Valley in the south central portion of the province. This area is described as a divide valley at an elevation range of 4,000 to 6,000 feet and is situated on the divide between two drainage systems. The major drainage to the west flows into the Thompson River and to the east and south the drainage enters the Nicola River system. This open-ended valley lies between low, rounded mountains in fairly heavily-wooded country. Prior to the commencement of copper mining activities, the first by Bethlehem Copper Corporation Ltd. over ten years ago, the valley was only sparsely settled. A few small ranches were in existence on the several Indian Reserves located along the valley bottomland. There has also been a small amount of logging activity in the valley, although much of the area is covered by dense lodgepole pine which has little or no value to the loggers. As the mining interest mounted with further discoveries of the disseminated copper ore typical of the district, much of the valley was covered with mineral claims and exploration drilling was carried on by several companies at various times. At the time Lornex was preparing to commence major construction work in early 1970, there was very little activity of any kind in the Highland Valley outside of the Bethlehem operation and a small amount of ranching."

Jan 1, 1973

By R. T. McAndrew

Introduction Drinnan is situated in the Prairie Creek coal area in the Foothills belt of Alberta. It lies on the main line of the Canadian National railway from Edmonton to Jasper. The exact location is shown on the map (Figure I). Interest in the field was aroused by several circumstances: Its proximity to Brule and Pocahontas on the southwest and to Coal-spur on the southeast led to the belief that coal might be economically produced here. There was already at Hinton a 3 ft. 9 in. coal seam being mined by Seabolt. The coal was of very good grade, being black and shiny in appearance with well defined cleavage and a heat value of 12,000 B. t.u. Outcrops of coal had also been noticed on the north side of the Athabaska river and Fish creek. These facts led the Jasper Coal Company to investigate the field. This Company considered taking over the Seabolt property at Hinton, but, owing to the size of the seam, this plan was abandoned and prospecting by diamond drills and test pits was started two years ago in the district east of Hinton. After prospecting had been completed, the most favourable district was found to be in township 51, ranges 24 and 25, west of the 5th meridian. The Company&apos;s lease includes all or parts of sections 18, 19, 20, and 28 in range 24, and sections 10, 11, 12, 13, and 14 in range 25. The approximate boundaries of the property are the Canadian National railway on the north, Happy creek on the west, and Cache Percotte creek on the east. The lease comprises 3,100 acres, and the total amount of coal in sight is estimated at 100,000,000 tons.

Jan 1, 1931

By John A. Allan

Introduction There are times when meditation on the past is worth while. Too often does it happen that in the busy routine there appears t9 be little time for reflection, and little good or benefit to be derived from what has already taken place, or what has become past achievement. Under conditions such as those that prevail at present, consideration is being given to many subjects that a few years ago were not looked upon as worthy of time or thought. The temporary lull in industrial development is permitting of a stock-taking investigation, a perusal of past activities, and a planning for future development with the return to normality. It is not proposed to include much new data in this address, but the endeavour will be made to survey, in resume, the sequence of events which led up to the birth of the mining industry in Canada, and to show how, as new discoveries were made, the centres of interest changed from time to time until mineral development extended across Canada from the Atlantic to the Pacific. It will appear, also, that external causes have accentuated mineral development at one time and retarded it at another. Early Records A, historical background to the mining industry extends even to an earlier date than the discovery by white men of that part of the continent of North America represented by Canada. It has been stated that the aborigines were still in the neolithic stage when the white man arrived. One metal only was known to the natives, and that was copper, obtained from possibly many parts of Canada, but particularly from the shores of lake Superior in Ontario, from the Coppermine river on the Arctic coast, and from die coastal regions of British Columbia.

Jan 1, 1933

By D. J. Lucifora

Monitoring-While-Drilling (MWD) is a proven technique that records instantaneous on-drill parameters which can be used to supply contextual information for in-situ, down hole conditions, such as: changes in geology, the presence of pre-existing fractures and dynamic alterations, down hole conditions including bit bailing, bit blockages and bit wear, and improper drill operation. This technique has been widely used in the oil and gas industry and, eventually, it was transferred to the mining industry. A challenge when analyzing and interpreting MWD data is in utilizing proper filtering which enables one to properly eliminate any ?noise? from the signals of interest. Overall the importance of MWD data is that, through the collection of operational field-based data, a dataset can be acquired which allows experimentation and analysis to be carried out. Such a dataset is often impossible to replicate in a laboratory setting. If successful, and through iterative refinement, any promising method can eventually be implemented on-machine and using real-time monitoring techniques. This paper will provide a state of the art review of presently used MWD techniques and applications in industry. The paper?s primary focus will be on shallow, mining-style, blast hole drilling but will also take into account techniques and applications utilized in oil and gas drilling which have not been adopted in the mining industry. In the cases where MWD techniques and applications exist solely in oil and gas drilling the paper will examine and comment on the potential utility of technology transfer to mining applications.

Aug 1, 2013

By R. Duinker

"This paper, an update to the 2003 paper titled "Knowledge, Technology and Profit" (Twigge-Molecey, 2003) analyzes 45 "problem projects" from the mining and metals industry over the last eleven years representing $133 billion in CAPEX. The projects have been designated as "problem projects" as they did not meet their owner’s initial expectations for project performance as defined in the paper. This paper explores some of the challenges that were present, through interviews with the knowledgeable individuals that were familiar with the projects and investigations using publically available information. The aim of the exercise was to identify the key challenges faced by the projects, and the contributing factors that led to the project failures so that the lessons can be applied to future projects.The project challenges have been categorized into four themes, technical, organizational, environmental & social and missing "homework" prior to board approval. Of noteworthy interest is that environmental permitting aspects have risen to become a significant and notable contributor to problem projects in 11 years from 2003 to 2014. It is further observed that many projects have been challenged by increasing size and complexity and with execution in more remote locations since the previous paper.It is a reality that every project will face challenges. Some projects are simply more challenging than others, and success or failure of the project is often determined by whether the project team is fully prepared to respond to the challenges. This in turn is largely dependent on whether the project "homework" was adequately completed and considered for all aspects of the project."

Jan 1, 2015

By Jack G. Hazan

The Critical Path Method is the modern scientific answer for solving the planning and scheduling problems inherent in today&apos;s complex projects. With this method, nothing is left to chance. All resources are controlled and kept to the minimum. The various phases are properly planned and strategically determined. Optimum conditions are evaluated for the most economical and fastest way to complete a definite project. The method must be fully understood and implemented with positive data and continuous feedback to obtain the best results. This paper covers the various aspects of the Critical Path Method and mentions some of its applications in the mining and metallurgical fields. T 0 progress to a higher state of human welfare necessarily involves sacrifices. The greatest sacrifice is to relinquish social freedom in favour of economic freedom. In the old days, for example, a cobbler was free to work at whatever time of the day he chose; today, he can&apos;t. He is now forced to adapt himself to environment and to work at stand-

Jan 1, 1965

By A. E. Aho

"The material presented in this paper will be subject to modification as new data become available, but it is presented in the hope that it will inspire more intensive mineral exploration and geologic studies of what appears to be one of Canada's richest mineral provinces. A metallogenic province 400 by 150 miles in extent, lying mostly northeast of Tintina trench, encompasses most of the base metal deposits of Yukon, as well as deposits of other metals. Its main features are northwesterly trending arcuate fold belts, with several orogenic axes, which include most of the metamorphosed rocks, granitic intrusives and mineralization; and which are modified by regional uplifts, northwest-striking fault trenches, and lesser transverse folding and faulting.The main base metal occurrences and their regional controls are summarized briefly. Most of the replacement-type deposits are localized in late Proterozoic to early Paleozoic rocks, particularly Lower Cambrian -probably because these are the most physically and chemically favourable hosts encountered in an appropriate temperature and pressure environment; perhaps because of early age of deposition. Most of the deposits also occur near heat sources or intrusives with associated structural uplift, which has, moreover, served to expose the older rocks. They also tend to occur near known or suspected regional fault trenches, such as Tintina, Macmillan and Hess, although this relationship may be fortuitous. In detail, they may be localized in fold axes, flat-lying beds or other appropriate structural traps. Vein-type deposits are fracture-controlled and localized by dilational localfties, the competence of wall rocks and ""damming"" effects.In the Anvil district, large stratiform iron-zinc-lead replacement deposits lie parallel to gently plunging flex-ures in phyllite in a zone parallel to the Tintina trench, along the southwest flank of the arch-like Anvil batholith. About 80 million tons of massive sulphide ore probably existed before erosion of the Faro orebody, the Vangorda deposit could have been of similar magnitude before erosion and much more tonnage probably remains to be discovered in the district. The Anvil deposits may differ from others found to date in Yukon, but resemble the Sullivan orebody of southeastern British Columbia in their large size, localization in essentially non-limy peptic to arena-ceous host rocks of Proterozoic or early Paleozoic age and proximity to the Rocky Mountain -Tintina trench sys-tem. These features suggest an origin from primordial subcrustal sources.More major ore deposits, not only of lead, zinc and copper but probably of other metals as well, will no doubt be found in similar environments in Yukon or Alaska. Thus, the base metal province of Yukon offers challenging opportunities for prospecting, development, field studies and basic research."

Jan 1, 1969

By R. Boom

Corus Umuiden, formerly Hoogovens, was the first steel plant in Europe after Voest to introduce oxygen steelmaking. In the decision-making process contacts with Dofasco in Canada about the production of formability steel grades were crucial. In developing oxygen (LD-) steelmaking high liquid steel output rates had to be combined with accurate process control. For ingot casting static models with input control and sampling during interrupted blowing were sufficient to deliver liquid steel within the required carbon, phosphorus, sulphur and temperature windows. Computers were introduced to perform the complicated charge calculations. Continuous casting called for strict control of composition and temperature at process end point and made predictable timing crucial. Dynamic control was introduced based upon sub lance measurements and waste gas analysis. Reliable disposable measurement sensors were developed in a concerted international action. Dissolved oxygen at blow end deteriorated the quality of low carbon aluminium killed steel grades. Blowing gases through the converter bottom improved process kinetics, resulting in lower carbon-oxygen products, yield increase and better phosphorus removal and generated new families of hybrid blowing processes. Introduction of secondary metallurgy facilities such as argon stirring stations, vacuum degassers and ladle furnaces relieved the demands for strict BOF end point control. Desulphurisation of hot metal became standard practice. In regions with scrap shortage hot metal desiliconisation followed by dephosphorisation, was introduced in the blast furnace cast house and hot metal transfer ladles. Later redundant converter vessels were used for pre-treatment, resulting in a two-stage process. The fundamentals of oxygen steelmaking are described and a vision on the future is presented.

Jan 1, 2004

By A. Varma

Successful technology commercialization occurs when a company is focused on creating shareholder value by providing a reliable product at a price point attractive to the market, while at the same time maintaining strict control of its internal cash burn rates. Developing a technology platform and a market platform are equally important in the commercialization of new technologies such as fuel cells. This paper will discuss some of the key barriers that may prevent successful market entry for emerging and disruptive technologies, such as: R&D priorities, supply chain / manufacturing issues, materials, cost reduction strategies, customer needs, developing a market pull strategy, institutional barriers such as existing regulatory/approvals processes and/or current design/purchasing practices, product reliability and resilience, and finding the right path to market. SDTC is an arms length foundation that aims to financially support the successful market entry of emerging and disruptive technologies that can provide significant environmental benefits to Canada. The fuel cell industry, which represents one such technology, is at a critical point in its evolution where market receptivity and the technology platform are converging to potentially create significant customer advantages for fuel cell products being developed today. Since its inception in 2001, SDTC has received over 850 business cases from which it has identified successful strategies to overcome the noted barriers to commercialization. While maintaining commercial confidentiality, the SDTC database will be mined to: Identify specific success stories that have overcome various barriers and discuss their strategy; Identify specific fuel cell related industry experiences that hinder successful market uptake. The general attributes and trends of successful technology developments identified in this paper will hopefully provide guidance to technology developers and prepare them to successfully tackle the next set of hurdles on the path to commercializing their technology, once they have proven their technology works in the laboratory.

Jan 1, 2005

By Panagiota Tsolis-Katagas, Basilios Tsikouras, Tassos A. Grammatikopoulos, C. Katagas

"Mineralogical techniques including microscopic methods, reflected and transmitted light microscopy, Cathodoluminescence (CL) and Scanning Electron Microscopy equipped with an Energy Dispersive Spectrometer (SEM-EDS), are useful in determining the quality of industrial minerals. They are essential for studying ores and metallurgical products including the evaluation of physical characteristics of the mineral, paragenetic relationships, associations with possible deleterious contaminants (e.g., sulphides), spatial distribution within the ore zones and liberation characteristics. The methods are inexpensive, and provide quick identification and distinction among the industrial minerals and the gangue minerals in a section. Additionally, SEM is necessary to reveal complex textural sequences and 3-D measurements of minerals and quick semi-quantitative analysis.Common analytical methods include Electron Microprobe Analyses (EMPA) and Whole Rock Analysis (WRA) (commonly with XRF and ICP) for major and trace elements. The EMPA analyses of industrial minerals provide information on the purity of the analyzed grains as opposed to the bulk chemical analyses that may be misleading due to contamination by other associated common “gangue” minerals. These techniques have been implemented for the case studies of wollastonite, V-magnetite and muscovite. Therefore, these methods can provide extremely useful information and lead to the implementation of a successful pilot-testing programme.MINERALOGICAL EVALUATION OF DEPOSITSDespite their considerable and increasing economic importance, industrial mineral deposits have traditionally been neglected by economic geologists, and are only rarely the subject of the detailed analysis widely lavished on metallic mineralization. Moreover, in that they generally represent concentrations of “normal” rock-forming minerals, albeit commonly with particular textural and/or geochemical features, they have tended to fall between the mainstream of petrogenetic studies and mineral deposit research (Grammatikopoulos 1999). For many industrial minerals, little attention has been paid to the factors responsible for their local concentration as large and high-grade bodies. This comparative neglect has particularly been the case for minerals such as talc and wollastonite, widespread in metamorphic rocks, in which they are reasonably interpreted as components of assemblages derived, respectively, from pelitic sediments, ultramafic igneous rocks and siliceous limestones."

Jan 1, 2003

By D. R. Keck

"SINCE the .Canadian Chemical Company has no direct connection with mining operations, and I have had no experience with mining, there is little I can tell you that you do not already know. However, we have had considerable experience with certain types of metallurgical problems and I would like to discuss with you some of these problems and their solutions by our metallurgists.In order to acquaint you with the type of plant and processes to be employed at Edmonton, I would like first to take a few .minutes to trace briefly the history -of the Canadian Chemical Company's affiliate, The Celanese Corporation of America. In the early •part of the twentieth century, two young Swiss brothers, Camille and Henri Dreyfus, received their P.h.D. degrees in chemistry. They were extremely interested in work which was being carried on at that time to find a suitable synthetic fiber that could compete with natural fibers, both quality and price-wise. Early man-made fibers were both coarse and hard to dye. The Doctors Dreyfus• poured all their earnings into research and ultimately developed cellulose acetate filament. During World War I, the Dreyfus brothers were invited to the United States to produce cellulose acetate 'dope' for airplane wing coverings. Dr. Camille Dreyfus built the first American plant for fiber production at Cumberland, Maryland, in 1924.Due to resistance of textile mills to the new fibers, Celanese was forced to set up its own dying, weaving, and finishing mills to prove the new materials. Through the years, however, this operation has •been retained primarily for fabric development purposes,.. with the majority of the acetate being sold to other textile mills."

Jan 1, 1953

By W. K. Gowans

The Sullivan Concentrator treats a complex sulphide ore consisting mainly of galena, marmatite and pyrrhotite. The ore carried minor values in silver, antimony, bismuth, indium and tin. The products of the concentrator are lead, zinc, iron and tin concentrates. The minor metal values other than tin are recovered from the concentrates by the refining processes in the smelter at Trail.The concentrator was completed in 1923 and first operated with a capacity of 2,500 tons per day. In the years 1926 to 1929 changes to equipment and buildings brought the operation up to 5,500 tons per day and then, in the years 1935 to 1945, the daily tonnage was raised to 8,500 tons. After 1945, the rising insoluble content of the ore made it necessary to consider the construction of a Sink-Float plant. At this time consideration was also given to the construction of a new crushing plant underground to replace the rolls crushers and cone crushers located at the concentrator. By 1949, construction of the Sink-Float plant was completed along with a new underground crushing plant, and an electric haulage way between the underground crushing chamber and the Sink-Float plant. The ore was hauled in forty 14-ton car trains which discharged into a 3,000 ton receiving bin by means of an air operated five car rotary dumper. With the start up of the,Sink-Float plant, a 1 ½ ft. by 12 ft. Hardinge rod mill was also brought into operation. The Sink-Float plant made it possible to treat 12,000 tons/day of mine run ore with up to 40% of this being rejected as float.

Jan 1, 1975

By Arnfinn Prugger

"The construction of the new Scissors Creek shaft at the Rocanville mine, the first potash shaft successfully completed in Saskatchewan Canada since 1979, is summarized here. Located 15km from the existing Rocanville surface plant, this new 6 m inside-diameter, 1121 m deep service shaft was built for fresh-air ventilation and access. Shaft construction in the Saskatchewan sedimentary basin involves sinking through five different rock-types: glacial tills, shales, sandstones, carbonates and salts. The first four rock- types are all water-bearing, and the salts will dissolve in water. This results in five different sinking challenges and requires five different shaft lining designs. The upper 580 m of rock (the till – shale – sands sequence) was frozen before sinking, and grouting methods were used for water control through deeper carbonate levels. Challenges that were faced and overcome during shaft sinking are reviewed, and ideas that future operators working in sedimentary basin environments might consider in order to avoid these difficulties are discussed.INTRODUCTIONThe Nutrien Inc. (formerly Potash Corporation of Saskatchewan Inc. / PotashCorp) Rocanville potash mine in southeast Saskatchewan, Canada has been in continuous production since 1971. Devonian potash, formed approximately 380 Mybp, is mined in a sedimentary basin environment at approximately 1000 m depth below surface in this area of Saskatchewan. The predominant use for finished potash products is fertilizer: potash fertilizer is concentrated and nearly pure KCl (i.e. greater than 95% pure KCl). Currently 10 potash mines are in operation in Canada, all in Saskatchewan. In 2018 Saskatchewan mines produced ˜ 23 million tonnes of finished potash products, which is approximately 35% of World demand of ˜ 66 million tonnes for the year (e.g. Nutrien Inc., 2019).In November, 2007 it was announced that the Rocanville potash mine would be expanded to increase production from 3.0 Million tonnes per year (Mtpy) to approximately 6.0 Mtpy of finished potash products, requiring an increase in hoisting capability from approximately 9.0 Mtpy to over 18.0 Mtpy. The Rocanville potash mine has historically been accessed through two shafts: a production and ventilation exhaust shaft, and a service and ventilation fresh-air shaft located approximately 200 m from each other. All surface offices, processing facilities, etc. are situated near these original shafts.A very important part of the recent Rocanville expansion involved the construction of a new service shaft (6 m diameter, 1121 m deep) for fresh-air ventilation and access, approximately 15km west of the existing surface plant. Once this third shaft was completed in 2015, the historical service shaft was converted to a second exhaust and production shaft. Three shafts are now available for mine access, ventilation and ore hoisting at Rocanville. As of December 31, 2017, annual nameplate capacity for Rocanville was 6.5 million"

Jan 1, 2019