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By W. J. Bennett

"I AM very happy to have this opportunity of speaking to the Montreal Branch of the Canadian Institute of Mining and Metallurgy.I have selected as the subject of my remarks transportation in that area which is at present our only source of uranium -Northwest Canada. Considering the widespread interest in atomic energy, the end-product of uranium, it may be wondered why I have not chosen to speak of a more spectacular aspect of the development. I hope it will be evident from what I have to say that transportation plays a very dominant role in our effort to maintain a continuing supply from Eldorado's producing property at Port Radium on Great Bear lake and from its coming producer at Beaver lodge Lake in Northwest Saskatchewan. Moreover, transportation has such a bearing on the entire mineral development of the Northwest that it cannot help but be of concern to an organization of this kind. Finally, the transportation problem, of which I shall try to tell you something, is quite unique and the story of its solution or partial solution is, I believe, an interesting one.Transportation experience on this continent indicates that the cheapest method of moving freight is still by water -with •rail, highway, and air transportation following, and in that order •of economic significance. Excluding rail transportation, since the area has as yet no railway lines, this order also applies in the Northwest. I shall direct my remarks to the two kinds of transportation which serve our uranium producers -water and air."

Jan 1, 1952

By R. E. Johnson

Seventy years after the start of the Industrial Revolution in Great Britain, as reckoned from Arkwright's water frame patented in 1769, there was a significant development of the metallurgical industry in Virginia. In Britain, crucible steel had been rediscovered by Benjamin Huntsman in 17~0, and this made spring and tool steel more generally available. The metal-turning, screw-cutting lathe, including the basic principles recognized in today's engine lathe, was developed by Henry Maudslay about 1797. Wrought iron, as manufactured by Henry Cort's process patented in 1784, was readily available. Richard Trevithick's highpressure steam locomotive had met its test on the Pennydarren tramroad in 1804, and George Stephenson had built his famous Rocket, along with several other locomotives, at Newcastle around 1828. Puddling furnaces and a rolling mill had been placed in operation at the Tredegar Iron Works in Glyn Sirhowy, Monmouthshire, Wales, in 1807. In the United States, expanding commerce and a growing population resulted in continuing development from the Chesapeake to Virginia's Blue Ridge, and this demanded improved means of transportation. Ore deposits rich in hematite had been found in Virginia's Piedmont during the Colonial period, and a number of blast furnaces now dotted that area. The products of these operations were mostly pots, kettles, stove parts and like items for local trade. The James River and Kanawha Canal was incorporated in January 1785. Its eastern leg, winding along the slope of the high bluffs overlooking the river, was completed about 1800. About two dozen railroads were chartered in Virginia between 1830 and 1837. With expanding population and steady industrial development came a need for metallurgical products. Throughout the eastern United States, numerous metallurgical enterprises sprang up, and many of these flourished. The purpose of this article is to outline the development of one Southern metallurgical company, the Tredegar Iron Works, which was to have a significant impact on the industrial development of Virginia and the fighting of the American Civil War. Although the Tredegar Iron Works no longer exists, remnants of the early operations have been restored, and the current status of the site is also presented.

Jan 1, 1999

By J. M. Cummings

CONSIPERABLE information on the industrial or non-metallic mineral resources of British Columbia has been published. For a general resume of the subject, reference may be made to a paper presented by A. M. Richmond before the Annual General Meeting of the Institute in 1935 (1). To avoid duplication, the present paper is confined to a discussion of the existing industrial mineral industry of the Province and of the factors governing its present and future development. British Columbia's mineral production in 1936 had a value approximately 15 per cent of that for the whole of Canada. Preliminary estimates for 1937 indicate that this proportion has been maintained, although the totals have increased about 25 per cent. The following table presents comparative figures, for the year 1936, illustrating the relative importance of the major divisions of the mineral industry in British Columbia and in Canada as a whole.

Jan 1, 1938

By G. Scamans, J. Lazaro-Nebreda, Z. Fan, J. B. Patel

"Melt quality is crucial for both continuous and shape casting of light alloys and in order to improve it, removal of excessive inclusions, accumulated impurities and unwanted gases becomes necessary. To address this problem, a new multi-purpose high shear liquid metal treatment technology, based on intensive melt shearing by a rotor/stator unit, has been developed. The device ensures achieving uniform temperature and chemical composition and an efficient dispersion of gas and solid phases in the melt with minimal disturbance of melt surface, and can be used, among other things, for de-gassing and de-ironing of Al-alloy melts. Efficient degassing is achieved by dispersing each argon bubble into many small ones, which significantly increases the overall surface area of the bubbles and the time they remain in the melt capturing hydrogen before reaching the surface. This allows using much lower inert gas flow and mixing times than conventional rotary degassing. When applied to Al-alloy scrap, with accumulated iron, the high shear melt treatment speeds up the nucleation and growth of primary Fe-rich intermetallic particles, allowing a faster removal rate. Therefore it reduces processing times, increasing recycling productivity, and facilitates full metal circulation of secondary Al-alloys.INTRODUCTION Aluminium and magnesium alloys are widely considered in various industrial sectors for the purpose of weight saving (Polmear, 1995). In particular, they are used in the automotive sector, where components are mostly manufactured by high pressure die casting (HPDC) because of its simplicity and relatively low cost, but efficiency and mechanical properties are quite low compared with other processes. To date, the main focus to overcome this problem has been for improving the HPDC machinery (Dahle, 2001) but little attention has been paid to the opportunities of controlling the nature and quality of the molten metal supplied to the die. In this way, liquid metal treatment, which involves a variety of physical and/or chemical processing methods to improve melt quality prior casting, is crucial for both continuous and shape casting products."

Jan 1, 2018

By Leonard L. Fischman

It is important to define "adequacy," and the most useful definition is a continuing availability of mineral materials under cost and other conditions which imply no significant burden on the achievement of otherwise attainable levels of consumption and well-being. For current decision making, it is sufficient to consider adequacy just to the end of the century, with some regard being given to then remaining mineral inventory. A comparison of cumulative demand projections to the year 2000 with already identified reserves ( economically recoverable amounts in known deposits) suggests little reason for concern with world adequacy of iron ore, aluminum, manganese, chromium or potash. Conservative estimates of "prospective" reserves (amounts producible at today's prices, but yet to be discovered) suggests that there are ample quantities of virtually all other mineral resources as well. A probable exception is oil and gas, of which there may be scant amounts remaining after the turn of the century. However, there is an evident sufficiency of substitute forms of energy, though it is difficult to see just where developing technology will take us. The critical questions have to do with the increasing dependence of the industrialized countries on external sources of supply , coupled with a new international politic s which complicates the problem of insuring timely development of, and access to, remaining deposits. In this context, Canada, a still mineral-rich nation, is in one of the more favorable positions.

Jan 1, 1977

By Sandra K. Zacharias

Brass, a deliberate alloy of copper and zinc, has been known since before Roman times. There are two main methods of making brass: (1) Cementation or calamine process - crushed zinc ore (calamine, ZnC03 , or calcined calamine, ZnO), is mixed with charcoal and small pieces of metallic copper and heated to about 900°C in a closed crucible, (2) Alloying - metallic copper and zinc are melted together in a reverberatory furnace. According to most modern authorities (e.g. Smith and Forbes 1955), the calamine process was the only one used in western Europe prior to the 18th century. At that time, the alloying technique began to take over, because metallic zinc was successfully produced on a large scale for the first time. Previously, this had been a problem because zinc vapourizes at 906°C or about the same temperature at which it can be reduced from its ore. Thus, some means had to be devised to collect and condense the zinc vapour (Tylecote 1976). Metallic zinc was known, however, earlier than the 18th century A.O. Several early finds have been made, including a rolled sheet of metallic zinc found in excavations at the Athens Agora dating to the 3rd to 2nd century B. C. (Farnsworth et al. 1949). The Chinese were producing zinc by at least the 10th century A. D. and, by the 17th century, Chinese zinc ingots were being imported into Europe by the Dutch East India Company (Needham 1974). Metallic zinc is also mentioned in several European documentary sources from the 16th century (e.g. Paracelsus, Agricola). This study traces the changes in Western brass making methods from Classical to Renaissance times by examining documentary and archaeological evidence.

Jan 1, 1999

By B. Wasmund, B. Haneman, G. Sheehan

Success in implementing new technology for metallurgical processes is not a foregone conclusion: This paper includes a survey of 23 new technology-based metallurgical plant start-ups, in which the authors have identified 7 successes, 9 difficult start-ups, and 7 failures. Success is defined not only as meeting the schedule and budget to the end of mechanical completion; the key goal is a fast ramp up to the full design production level, with minimum plant and equipment modifications required after start-up. This paper sets out the key factors that underlie achievement of a quick production ramp up curve, as determined from the authors' project experiences and a quantitative analysis of over twenty metallurgical plant start-ups, both pyrometallurgical and hydrometallurgical. Thorough test-work and pilot plants, plus appropriate scale-up to the full commercial plant, are key determinants of success in implementing new technology in metallurgical processes. Another critical factor is the number of new elements and their interactions. Project phasing is also particularly important for new technology projects, with appropriate review after each phase to develop a risk mitigation plan for the subsequent phase. New technology projects need committed champions to advance the project in the face of sceptics, but also require dispassionate and unbiased experts to ask the hard questions. As a project evolves, it is important to periodically question the appropriateness of assumptions, as well as to re-assess the relevance and completeness of data from test-work I pilot plants I industrial analogues. Sufficient human and financial resources are required to complete the often arduous implementation phase. During the ramp-up period, the operation generates little positive cash flow; however, significant expertise and capital are required for the de-bottlenecking projects that are often necessary to reach the plant's design output level.

Jan 1, 2011

By J. L. Jambor, J. E. Dutrizac, J. B. O'Reilly

The present-day metallurgical community is quite familiar with the use of jarosites [MFe3(S04)2(0H)6 where M = K, Na, NH4, Ag, 1/2Pb, etc.] as a means of controlling iron, alkalis and sulphate in hydrometallurgical circuits. This modern precipitation technology has found an increasingly widespread application in the zinc industry111 and is gradually also being extended into the hydrometallurgical processing of copper and cobalt121 . The chief advantage of jarosite precipitation is that the iron precipitate settles and filters well, and gives low losses of divalent metals in the washed residue. Although this jarosite precipitation technology was developed only within the past twenty years, man's involvement with jarosites extends back to antiquity, and jarosites have played an important role as a source of silver in several ancient metallurgical centres. In the early days of this century, argentojarosite was an important local source of silver at the Tintic Standard mine, Dividend, Utah, where over 200 000 oz of silver were recovered from highgrade natural jarosite over a three-month period 131 . At the Matagente mine in Peru, pockets of argentiferous plumbojarosite up to 40 m thick were mined and processed by the Indians prior to the arrival of the Spaniards14-51 . In Cyprus there are vast jarosite deposits associated with the ancient mining sitesl51 , but exploitation of these jarosites has been insignificant because of their low silver values. The most extensive mining of silver-bearing jarosite, and certainly the oldest documented instance of such jarosite exploitation, was in the vast pre-Roman workings at Rio Tinto, Spain. This mine, the greatest single miningmetallurgical site currently known from the ancient world and also the oldest site of more or less continuous metal production, has witnessed many metallurgical firsts. Aside from the initial processing of jarositic ores for their silver values, the development of large-scale hydrometallurgy also seems to have occurred at Rio Tinto. As early as 1737, copper was recovered by cementation on scrap iron from the mine waters at Rio Tintol51 . Large-scale heap leaching of calcined ore commenced with the British operations in 1876 and, by 1900, raw pyrite was heap leached to recover associated copper values161 .

Jan 1, 1999

By Karl J. C. Harries

"8.1. INTRODUCTIONThe purpose of this chapter is not to provide precedents or examples of provisions, but rather to offer some comments that may be worth considering in the negotiation or review of an agreement. These comments are not intended to be exhaustive. It must also be noted that, although the chapter is written in the context of a common law joint venture, the concepts and concerns for the most part apply equally to a corporation that is owned by only a few shareholders for the purpose of participating in the project held by the corporation.The corporation has the advantage of having much of its organization established by local corporate law, but the particular wishes of the shareholders will appear in a shareholders’ agreement. The principal differences will be surprisingly small, save for the acquisition provisions that appear in a farm-in agreement1 and the substantial portion of the joint venture agreement devoted to creating and organizing the joint venture entity. Where the joint venture agreement refers to venturers and committees, the shareholders’ agreement will refer to shareholders and the board of directors, but both will have to deal with such basic matters as decision-making, default, dispute resolution, first refusals, funding, and carrying out work on the project. For convenience, this chapter usually refers to “venturers”, which may be taken to include shareholders.Negotiations give rise to many varying circumstances and concerns, and the main asset of the negotiator is an open and flexible mind. A desired result can often be accomplished indirectly in circumstances where the other side has adopted an inflexible position on a suggested approach. As precedents and standard forms tend to focus a negotiator’s thinking, they can be counterproductive. It is after the deal has been agreed to that a precedent can be of great assistance to the draftsman.The concepts are arranged in alphabetical order for convenience, not to suggest their sequence or position in an agreement or their relative importance. An agreement should adopt a progression of subjects in what the parties consider a logical sequence to read and work with. However, experience has indicated that it is best to set out in a single article the substance of the deal (i.e. the terms relating to the farm-in and what the acquiring party has to do to acquire his interest), preferably near the beginning of an agreement. The acquisition of the interest is, after all, the first order of business. The joint venture provisions will then follow in a reasonable sequence. It is also worthwhile to devote a single article to any special provisions that may apply during the earn-in period. For example, it may be provided that, although all work is to be done by the acquiring party as operator (with the duty of care, liability, and reporting requirements as set out in the joint venture sections of the agreement), but during the acquisition period, the acquiring party, acting as operator, may be at liberty to do such work as he wishes, without the need for any committee or other approvals, and committee meetings may be suspended.2An agreement is divided into paragraphs and articles to make it easier for the parties to read and understand, and to assist a party in finding “that provision” when the need arises. A comprehensive table of contents will also assist the parties who must work under an agreement. An added benefit of a table of contents is that in preparing it, the draftsman sees the overall structure of the agreement and will often catch and correct flaws."

Jan 1, 2003

By Constantin D. Pitis

?Demand-side measure" means a rate, measure, action or program undertaken to conserve energy or promote energy efficiency?? (BCUC, 1996) In actual economical environment, business sustainability requires high-efficiency technological processes. That is why the efficiency concept has to be present at all levels of industrial activities. Nowadays, some purchasing decisions are still driven predominately by the purchase price, in spite of the evidence that such price represents up to 5 % to 7 % of the total costs of ownership with full consequences of energy efficiency and the impact on total ownership costs. The paper presents essentials of converter types and basics of the Global Efficiency (GEff) Concept that has been promoted over the last few years in South African industries (Pitis et al., 2006/7). GEff concept is proven as a useful tool used on price-efficiency decisions. Theoretical and technical aspects of this concept were substantiated with case studies. First part presented in this paper will describe how GEff concept was used on price ? efficiency decisions when single input or direct converters and systems (considered as low value equipments) have been replaced. Besides the impact of energy savings and new innovative developments, the paper suggests general other benefits of: ? Technical and economical performance improvements and competitiveness of mining corporations to international standards; ? Defusing incipient energy crisis in the sector; ? Improving environmental conditions; ? Creating new job opportunities in mining sector. Proposed concept in this paper could be further developed as models of improving companies? corporate energy policies.

May 1, 2010

By Theo. A. Link

ACCORDING to our office dictionary, geology is "the science that investigates the structure of the earth and its successive physical changes", and a geologist is "one who knows the science of the structure of the earth". No doubt this definition does not suit all of us. Another dictionary would have the definition slightly different. As an example, one dictionary stated that "a geologist is one who practices geology". (Some of our clients told us to quit practising and get to work). There are many different types of geologists engaged in various branches of the profession and some of these are further broken down into subdivisions so that specialization is becoming more and more prevalent. As a result it is, in some cases, doubtful whether or not we are actually dealing with a geologist in the generally accepted sense of the term.

Jan 1, 1956

"IntroductionThe Chairman, in his speech to this body last year in Montreal, stated that the Dominion Coal Board looked to and depended upon the Bureau of Statistics for statistical material, and the Bureau does collect and publish monthly and annual data on coal. It may therefore be asked why an officer of the Dominion Coal Board should prepare and give a talk on statistics.I would explain that it has been our experience in the Board that, since the supply and consumption of coal in Canada is subject to a seasonal ebb and flow, it can be more profitably studied on the basis of a twelve-month period ending on March 31st than of a calendar year, since the end of March does represent a fairly stable end point in this ebb and flow. The figures are not prepared or published by the Bureau on that basis and it has therefore been thought that a presentation on this fiscal-year period would be of interest. The Bureau of Statistics has agreed that this may be valuable and all the data here presented are based on the reports secured from various sources by the Mining, Metallurgical and Chemical Division, Dominion Bureau of Statistics. The only contribution by either myself or the staff of the Dominion Coal Board has been the tabulation in a different twelve month period, and the comments upon the picture presented.It should be noted that the data for the month of March, 1950, are not available in all cases and consequently the figures for that year contain an estimate for this month."

Jan 1, 1950

By C. G. McLachlan

Abstract This paper deals with the application of the cyanide process to recover gold from a pyrite concentrate produced by means of differential flotation. This concentrate before cyanidation contains from 0.09 oz. to 0.14 oz. gold per ton, of which only about 60 per cent is recoverable. The rest is so fine that it remains interlocked in the pyrite and therefore is not acted on by the cyanide. The concentrate also contains about 15 per cent pyrrhotite and 0.4 per cent chalcopyrite, both of which are cyanicides. The cyanicidal effect of the pyrrhotite is inhibited by preacracing the pulp with lime, and maintaining a high lime alkalinity during cyanidation. The effect of the chalcopyrice is reduced as far as possible by removing those particles which are free by means of a further flotation step immediately prior to cyanidation. This involves the flotation of some very fine material. After nullifying as far as possible these two cyanicides, the concentrate is cyanided directly, i.e., without being roasted. This leaves the pyrite available for subsequent sale as a source of sulphur dioxide and sulphuric acid, and the entire residue of the cyamde plant, amounting to about 500 tons per day, 1s now being disposed of in this way. Prior to deciding on direct cyanidation, a number of laboratory roasting tests were made. These showed chat, 1f proper control were exercised, a better recovery of gold could be effected from the roasted product than by the direct method of treatment. The tests also showed that the capital cost o the plant would be much higher than that needed for the procedure adopted. The possibility of subsequently selling the pyrite for its sulphur content would also have been eliminated. Introduction A previous paper has described in considerable detail the application of the flotation process to improve gold recovery from Noranda's milling ore, and in so doing has covered the production of an auriferous pyrite concentrate. The present paper deals with the recovery of gold by cyanidation from that concentrate. This gold, though intimately associated with the pyrite, can, for metallurgical purposes, be considered as all occuring in the native state.

Jan 1, 1946

By D. T. Pritchard

"Introduction""No accounting system is very good, and all of them are infinitely variable*.”The purpose of this chapter is to discuss those facets of a typical accounting system which are most commonly encountered by operating managers in mineral processing plants. However, before concentrating in any detail on these it is important to understand the broad purposes and basic techniques of any accounting system in any major business.The three broad purposes of an Accounting System are:- Administering, controlling, and recording the flow of cash in and out of the business. Cash is, of course, converted into other assets (or stores of value) such as inventory, plant and equipment, etc. These assets also have to be administered, controlled and recorded.- Internal reporting to Management for information, for control, and for use in making business plans and decisions. - External reporting to stockholders, government, lenders and other outside parties.In this chapter we shall organize our discussion of accounting practice in mineral processing plants around these three purposes of accounting and focus in some detail on specific practices and techniques with which operating personnel will be routinely involved. This chapter is divided into the following: Accounting Basics; Administration, Control and Recording of Cash Flows; Internal Reporting; Planning and Budgeting; Cost Control; and External Reporting."

Jan 1, 1989

By C. O. Swanson

CALCULATING the average grade of a gold deposit is a problem that presents certain unique difficulties. Particularly troublesome is the fact that the average of the samples taken from a deposit is likely to be higher than the grade of the ore that is eventually mined, even when allowance is made for dilution and other factors resulting from the mining operations. It would seem that this situation is due to the presence in the deposits of structural peculiarities which have not been properly taken into account, since estimating the average grade of the broken ore produced from the deposits does not present the same difficulty. It is therefore evident that structural considerations are of prime importance in estimating the grade of a deposit. This fact is clearly realized and taken into account in cases where the boundaries of the orebodies and the variations within them are easily recognized. But in many gold deposits this condition is not satisfied, a circumstance which can be regarded as the main source of difficulty. Lacking definite information concerning the structure, we are apt to use certain procedures which are either empirical or based on general probabilities.

Jan 1, 1945

By P. R. Geoffoy, T. Koulomzine

"The discovery of the Mogador deposit concealed by 100 feet of overburden was the result of combined application of geological reasoning, ground geophysical surveys, studies of glacial float and extensive diamond drilling. The ground was acquired because it lay on the projected intersection of the Manville and Laflamme River faults. Systematic ground prospecting led to discovery of mineralized floats. A first unsuccessful exploration campaign lasted several years and consisted of 137 drill holes.In 1951 the boulder nests were reexamined and an associat'on of the mineralized float with boulders of a granodiorite, unknown in outcrops of the district, was established. Consequently, ground magnetic surveys were extended and re-interpreted, and a large anomaly interpreted as corresponding to a batholith was outlined. The existence of the batholith was immediately confirmed by drilling and the Mogador deposit discovered in third hole of new drilling programme in a zone of fractured volcanics paralleling southern contact of batholith.The Mogador deposit is a complex replacement of silicified volcanics by pyrite, pyrrhotite, sphalerite, chalcopyrite and galena carrying values in silver and gold. A total of 1,230,000 tons has been indicated, most of it now classified as fully developed proven ore."

Jan 1, 1960

By A. G. Spencer, A. D. Taylor

This paper discusses some of the advantages and problems associated with the selection of large unit equipment for a metallurgical plant. A given flowsheet and material balance for an iron ore concentrator is assumed. Then two plant designs are developed, one utilizing a number of smaller-size equipment units and one utilizing the largest available equipment units. The mechanical and electrical problems are discussed and a comparison of capital costs is made. Finally, brief consideration is given to a plant de-sign using units larger than those which are currently available.

Jan 1, 1968

By J B. Magee

Sheep Creek Mines Limited has developed several operating techniques that have greatly assisted in keeping unit costs at reasonable levels. Some of the techniques, as described in this paper, include organization, accounting, warehousing, bonus and contracts. INTRODUCTION THIS paper is a non-technical report on operating techniques developed by Sheep Creek Mines Limited at their Mineral King mine, located near lnvermere, B.C. Depressed metal prices and continually rising labour and materials costs have necessitated a continuous search for method to keep operating costs down. The newly developed techniques and practices have greatly assisted in maintaining unit costs. Sheep Creek Mines Limited is a mining company incorporated under the laws of the Province of British Columbia. The Company's share capital is 3,500,000 common shares, witl1 a par value of 50 cents each, of which there are 1,875 000 shares is-sued. The Company has eight di-rectors. The administration, exploration and accounting offices are located in Nelson, B.C. The Company's working capital is approximately $1,500,000.

Jan 1, 1963

By R. Agius, A. Nacu

"Cyanide destruction technologies are implemented at gold and silver operations to comply with the International Cyanide Management Code and meet ever more stringent discharge limits. Currently, the most common chemical cyanide destruction processes used in industry are sulfur dioxide/oxygen, hydrogen peroxide, and Caro’s acid. The cyanide destruction process used at an operation must reliably generate streams of acceptable quality at all times, and depends on numerous factors, including permit discharge requirements, tailings chemistry, location, site-specific climatic conditions and size of the operation. Selecting the most appropriate cyanide destruction process and determining the process design criteria requires accurate laboratory testing. This paper presents and discusses the results of a number of cyanide destruction evaluations that have been conducted to reduce cyanide concentration in process solutions or cyanidation tails. Laboratory testing provides important insights into reagent consumption and other factors required to achieve the target residual weak acid dissociable cyanide (CNWAD) levels.INTRODUCTION Process solutions associated with the extraction of gold and silver contain several forms of cyanide. The most toxic form of cyanide is free cyanide, which can be present as a dissociated cyanide anion (CN-) or gaseous or aqueous HCN. Weak or moderately stable cyanide complexes such as those of zinc, copper and nickel are classified as weak acid dissociable (CNWAD). Although less toxic than free cyanide, weak acid dissociable cyanide complexes are considered “ecologically sensitive” forms of cyanide and are regulated in most jurisdictions. In practice, reported WAD cyanide values comprises both free cyanide and weak acid dissociable cyanide complexes. Cyanide complexes with gold, mercury, cobalt and iron are referred to as strong acid dissociable complexes (CNSAD) and are much more stable, even under mildly acidic conditions. Another term commonly used in cyanide chemistry is total cyanide, which represents all cyanide compounds present in solution. Total cyanide levels in solutions are always equal to or higher than WAD cyanide values and the difference between the two usually indicates the presence of iron-cyanide compounds. Typically in Canada, CNTOTAL levels cannot exceed 1 mg/L in solutions discharged to the environment."

Jan 1, 2017

By Nick Hazen

Many successful actions are required to bring a profitable extractive metallurgical operation into production. Competent process development performed within the project development schedule increases the chances of obtaining project financing and decreases the risk of engineering design errors being built into the commercial plant. The general sequence of steps in process development is well known: technology review, desktop studies, scoping studies, prefeasibility, and so on, with an increasing requirement for experimental evidence as the studies advance. This paper suggests principles for guiding process development work so that the efforts stay on track toward a smooth startup and a profitable commercial operation. It emphasizes closely aligning the research with the corporate goals of the mining company management, understanding the mineralogy and variability in the deposit, and guiding by flowsheet and material balance. Examples of hydrometallurgical process development leading to the early use of solvent extraction in the mining industry are given.

Jan 1, 2014