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By Johnson N. W

After an unsuccessful transfer from the laboratory to the pilot plant of galena flotation technology which used sodium metabisulphite and ethyl xanthate, laboratory flotation tests were conducted to identify any unusual variables which had a deleterious effect on the position of the lead rougher grade recovery curve for Hilton and Mount Isa silver-lead-zinc ores. Two variables (pulp temperature and contact time for ethyl xanthate and sodium metabisulphite) had important deleterious effects.The findings allowed a successful transfer of the laboratory process to a pilot plant scale process. The effect of temperature was important because the higher temperature (40°C) in the pilot plant pulp increased significantly the rate of reaction between ethyl xanthate and sodium metabisulphite. In the laboratory process at 20 to 25°C, the reaction rate was lower and did not interfere significantly with the process. The contact time for the two reagents was also important in the pilot plant scale process because of the higher reaction rate at 40°C.To employ ethyl xanthate in the pilot plant process, special precautions were required. Further, a collector (Aerofloat 241) from the dithiophosphate family was used successfully in the pilot plant process.

Jan 1, 1988

Jan 1, 1963

One would anticipate that after 40 years in the mineral industry it would be simple to project the trends at least 5 or 10 years into the future. However the last 20 years, 1950-1970, have been so different in the mineral industry from the years 1930-1950 that I suggest only 20 years or so are relevant to any forward projection.Those, of us that have been about during the last 40 years find it hard to relate the two periods.The first with the depression, low base metal prices, attempts to revive the gold industry, very little export of minerals, and finally World War II and the recovery period.The second, a period of unimagined discoveries and the reappraisal of a wide variety of minerals and metals-iron, coal, bauxite, beach sands, manganese, oil and gas, and nickel, to name but a few.The second period started early in the 1950s and was triggered off by the search for oil in Australia.Rough Range No. 1 was an important milestone in our history because it initiated a series of speculations and the re-examination of much of our thinking about our mineral resources. It lead to the discovery of bauxite and the start of a flourishing aluminium industry.The realization of the extent of the iron ore resources was another, major step and the influx of overseas capital and competence started the large wave of development made effective by the Japanese markets.The momentum of the late 1950s has carried us to where we are today and will undoubtedly carry us further forward in the next few years.All this development in the mineral industry has come at a time when our pastoral industries have reached a difficult period. I have no doubt that if it were not for the mineral industry Australia would at the moment be experiencing one of its blackest eco...

Jan 1, 1971

As we look back through the Proceedings of our Institute, we find few papers dealing directly with education and recruitment. Apart from papers prepared in the earlier decades of this century, there was little written discussion on the subject until the 1950s, and mostly this was by the professionals, the professors and lecturers who staff the various mining schools of Australia and New Zealand.I use the term "mining school" in its fullest and widest meaning, to cover all aspects from ore to metal, and not in the narrow meaning that the word might imply. At the same time, in restricting the parameters of this address to "ore to metal" I recognize that I am excluding the very important fields of physical metallurgy and materials science; this I do because there is a limit to the quantum of any paper, and in fact these subjects are more closely allied to the use rather than the production of metals.However, the lack of education papers does not mean that education has been regarded lightly by The Institute. Sir Maurice Mawby in his presidential address in 1968, reminded us of the original objectives of The Institute, one 'of which was, "To promote the arts and sciences connected with the economical production of the useful minerals and metals ...". Our present Royal Charter is more specific when it says that one of the objects of The Institute is, ". . . to encourage the study of engineering with special reference to mining and metallurgy ...". If we recognize that in itself membership of our Institute is one means of continuing our education, it is true that education has been a concern of The Institute since it was first founded.Occasionally in recent years, an intrepid president has ventured to tell the academics what the industry needs, and he generally does this in a "no-question" situation! However it is encouraging that those entrusted with mineral education have always accepted this; they keep coming back for more and ask us to tell them what we want, and they will provide it.In 1948 a considerable dialogue on education was initiated when a standing committee was established by the Council of The Institute. In the period 1949 to 1951, three papers were prepared under the chair...

Jan 1, 1974

By Jarek Jakubec

The new euphoria in diamond exploration brings with it a need to understand the challenges that new projects can face in different stages of the development and risks that the commercial outcomes from the new projects fall short of expectations. In many cases, the problems are related to a poor understanding of the technical risks and a failure to adequately address them during the course of investigation. Failure to evaluate all disciplines to the same level of certainty could lead to a situation where the important issues are only identified late in the project development, resulting in costly delays and financial difficulties. The diamond projects located in Canadian Arctic, with its challenging environmental, geographical, social, political and geological contexts are especially sensitive to the high variability of the outcome. This presentation highlights some of the technical aspects that could be the leading sources of risk in diamond projects and could ultimately result in inappropriate mine designs, reducing the economic outcome.

May 1, 2006

By Arthur L. Murray

"INTRODUCTION In compliance with those provisions of the organic act establishing the Bureau. of Mines which relate to improvement of health conditions of persons engaged in the mining, preparation, or treatment of mineral substances, sanitary surveys have been made of towns and villages housing the coal miners, metal miners, and mill and smelter employees of Utah.The purpose of the surveys is to afford studies of conditions prevailing in the various mining and smelter towns so far as concerns housing, water supplies, sewage disposal, refuse disposal the handling of foodstuffs, general sanitation, wash and. change houses, and the control of preventable diseases, all of which directly or indirectly have a bearing on the health and efficiency of employees and their families. Certain other factors have been added to the general sanitary surveys such as school and recreational facilities, which have a decided influence on contentment and efficiency. Through comparisons of favorable and unfavorable conditions and practices, and the dissemination of such information, improvements can be effected which will benefit both the employees and the employers.ACKNOWLEGMENTSAcknowledgment is made of the many courtesies shown by the officials of companies and towns visited. In some instances the towns were entirely under the control of officials of mining companies, being on company property whereas, in other instances, the towns wars incorporated not under company management. Particular acknowledgment is made of the assistance given by the Utah State Board of Health through Health Commissioner Dr. T. B. Beatty."

Oct 1, 1932

By Michael D. McGill

The effect of fragmentation size distribution as it relates to front end loader productivity was evaluated by comparing loader cycle times to fragmentation size of the shot rock. At Gold Mine in Southern Utah, a gold deposit containing both limestone and sandstone formations were blasted in the same shot.

Jan 1, 1994

By Peter Wells, Laxman M. Amaratuga, Todd M. Kanhai

"Certain mining methods (eg. Cut-and-fill) result in the contamination of run-of-mine ore with shotcrete. This shotcrete remains mixed with the ore throughout processing. Experimentation performed by Falconbridge Limited revealed that underground contamination of ore by shotcrete (eg. as little as 1% by weight) has led to ill-effects on the nickel recoveries from the flotation process in the mill. The nickel recoveries of contaminated samples were lower than tests without the shotcrete Contamination.To optimize flotation circuits it is important to know why the contamination has created these effects and also to find a method to abate or remove them. Laboratory testing showed that the age of the shotcrete was a factor in it’s effect on nickel recoveries. Younger aged shotcrete gave nickel recoveries lower than baseline nickel recoveries with no contamination. Older shotcrete gave nickel recoveries similar to the baseline.Literature on other cementitious material contaminations on ore revealed that a possible means of remediating this problem is the use of acid in the flotation. The initial pH in the flotation pulp was designed to be pH 9.2, but with the young shotcrete contamination the pH was in the neighbourhood of 10.5. Acid addition may act as a means of lowering the pH to the optimal operational value. Laboratory test work showed that acid addition brought nickel recoveries closer to the baseline."

Jan 1, 2000

By Lumley G, Rowlands D

The overburden slusher (OS) is proposed as a stripping tool that is expected to find application in overburden stripping operations including open cut coal and oil shale mines. OS is expected to combat the effects of increasing depth on the productivity of conventional dragline stripping.Although previously developed stripping techniques have included the use of drag scrapers the OS is sufficiently different as to constitute a new stripping method.A study undertaken at the University of Queensland during 1985 is believed to be the first major study on the use of the OS and preliminary economic results are very encouraging. It appears that the OS has the capacity to remove overburden at a cheaper unit cost than the equivalent powered dragline stripping machine at any comparable depth of overburden. The OS is not adversely affected by increasing stripping depth to the same extent as a dragline. In addition, the action of the OS machine allows for the lowering of spoil face angles, thereby reducing spoil slope stability problems encountered in deep open cut strip mines.

Jan 1, 1986

By M. A. Trevits, M. R. Thibou, A. Ozment, A. C. Smith, J. B. Walsh

The Excel No. 3 Mine is a room-and-pillar mining operation owned by MC Mining, LLC, a subsidiary of Alliance Resource Partners, LP, which produces coal from the Pond Creek Coalbed in Pike County, Kentucky. Late on December 25, 2004, a fire was discovered near the bottom of the slope and, after an unsuccessful attempt to fight the fire underground, it was decided to address the fire remotely from the surface. The mine operator developed a plan to fight the fire that called for the installation of temporary seals at the slope and mine shafts to eliminate the inflow of oxygen. In addition, the plan called for drilling and completion of vertical boreholes into select areas of the mine workings to monitor the mine atmosphere and inject nitrogen gas and gas-enhanced foam. Over the next 9 days, nitrogen gas was injected almost continuously and gas-enhanced foam was injected periodically as deemed necessary. On January 7, 2005 it was determined that the fire was successfully suppressed. This paper presents a discussion of the fire-fighting approach and an analysis of the results of the application of gas-enhanced foam technology.

By Peter Zhang

Pumpable cribs are being increasingly used in longwall tailgate entries and bleeders for roof support under abutment pressure. Their high peak capacity and confinement-controlled yield characteristics from reinforced-bags make them relatively safe and reliable standing supports for highly productive longwall panels. The pumpability of crib material over a long distance from the surface greatly reduces material handling and makes the underground installation more efficient and flexible. However, the performance of pumpable cribs is dependent upon crib properties, crib pattern, quality of installation, and geological and mining conditions. For proper crib selection and safe support design, it is critical to understand the basic technical requirements and performance of pumpable cribs in longwall tailgate entries and bleeders. Based on more than 10 years of experience using pumpable cribs for longwall standing support, the requirements and performance of pumpable cribs in longwall tailgate entries and bleeders under different mining conditions are presented. Experience shows that the load-displacement curve from full-scale lab testing is a good indicator of pumpable crib suitability for certain applications. Crib peak capacity, stiffness, and residual characteristics define its applicability to certain gate entries and bleeders under different cover depth. Crib pattern and spacing can be determined by abutment pressure level, roof, floor, and rib conditions, local roof stability, and ventilation requirements. To achieve proper in-situ performance, quality control of crib installation is also important.

Jan 1, 2012

By J. C. Edwards

A series of four coal combustion experiments (I)' was conducted at the National Institute for Occupational Safety and Health, Pittsburgh Research Laboratory in the Safety Research Coal Mine to evaluate the response of optical and ionization smoke and CO sensors to a small 0.61 m square smoldering coal fire which transitions to flaming combustion in the presence of diesel emissions. With the increased utilization of diesel engines in underground coal mines, it is important to be able to discriminate fire products-of-combustion (POC) from diesel emissions. One proposed method to accomplish this is the deployment and interpretation of multiple sensors.

Jan 1, 2010

Predicting Water Recovery from Flotation Cells

Sep 13, 2010

By E. B. Johnson

Cleveland-Cliffs lron Co., which operates Marquette lron Mining Co.'s Republic mine, conducted a test whereby 35,000 tons of self-fluxed pellets were produced in the grate-kiln system from specular hematite flotation concentrates. A brief description of the pelletizing plant is presented along with pertinent operating details. Date is included which compare operating conditions and the chemical and physical properties of the green and fired pellets for the self-fluxing pelletizing test with the normal acid pelletizing operation. The success of self-fluxed sinter in enhancing the operation of the blast furnace during the past few years has reasonably led to the assumption that the use of self-fluxed pellets might result in even greater furnace efficiencies. A great share of development work in agglomeration has been directed towards techniques related to the production of self-fluxed pellets, but only a limited tonnage of self-fluxed pellets had been produced on a commercial scale until this past year when The Cleveland-Cliffs Iron Co. produced 35,000 tons of such pellets by the grate kiln system at the Republic mine during the period May 21-June 5, 1962. REPUBLIC'S GRATE-KILN PLANT The grate-kiln pelletizing process consists of four stages, namely: feed or balling circuit, traveling grate, rotary kiln and annular cooler (Fig. 1). The balling section is conventional and utilizes four 9x30-ft balling drums in closed circuit with 5x14-ft vibrating screens having 3/8-in. rod decks. The traveling grate is 12 ft wide by 126 ft long and has 14 windboxes — six in the drying section and eight in the preheat section. The rotary kiln is 15 ft ID shell and 114 ft long. The annular cooler is 40 ft in diameter and has 12 windboxes. The cooler is divided into two zones by a moveable curtain wall. The high temperature air from the first zone is used as secondary combustion air in the kiln. Normally the only heat supplied is through the burning of No. 6 oil in the single kiln burner. Hot gases pass counter to the pellet flow through the system. The exit gases from the kiln pass down draft through the preheat section through cyclones and are drawn through the drying bed prior to exiting via the stack. The temperatures are normally held within the following ranges: Kiln 2400-2445 °F Preheat 1850-1950°F Drying 480-520°F Exit gas 200°F Pellets 120°F The design capacity of the Republic mine grate-kiln system was 2500 Itpd. Sustained production in excess of 35% over design capacity has been achieved. No screening of the cooler product is practiced. PELLETIZING TEST CONDITIONS When a decision was made to proceed with a test at the Republic mine pelletizing plant to produce 35,000 tons of self-fluxed pellets, several potential failure factors had to be carefully considered. Research work on a batch and pilot plant scale indicated that the grate-kiln system at Republic would require some major changes in order to obtain optimum conditions. In many cases compromises were agreed upon as major equipment changes and revisions were not feasible. The pelletizing conditions which laboratory development tests revealed were required in order to insure successful production of self-fluxed pellets were: 1) Good mixing of limestone and concentrate and proper moisture control; 2) Higher gas flow rates in the preheat section than are normally used; 3) Higher preheat temperatures than normal; 4) Maximum kiln temperature 2350°F. There was just cause for concern about balling problems that might occur. Approximately 10% of dry pulverized limestone was to be added to the specular hematite concentrate just ahead of the Pekay mixers on the belt feeding the balling drum. Large scale

Jan 1, 1963

The discussion in this paper centres on examples of mining that are drawn mainly from the coal mining industry. The intention is to review the opportunities that exist for incorporating environmental planning into mining industry practice in New Zealand. The coal mining examples serve to make some general points which have some application for many types of mining.

Jan 1, 1981

The paper outlines the development of a solvent extraction process for the recovery of scandium, yttrium, thorium, and heavy lanthanides from waste sulphate liquor at the Port Pirie uranium treatment plant. A summary is given of known solvents for these elements, including the recently developed alkyl-phosphoric acid esters which are applicable to sulphate solutions.A kerosene solution of di- (2'-ethylhexyl) phosphoric acid (EHPA) has been suggested by some workers as a suitable solvent for fractionation of the lanthanides. Experimental work with this solvent showed that it could be used for initial recovery of the above elements from low concentrations in the complex sulphate liquor. In particular, scandium could be recovered as a high grade product by extraction with 0·lM EHPA, followed by a purification strip with 9N sulphuric acid, and final stripping of scandium with sodium hydroxide solution.To enable alkaline stripping to be used successfully, the kerosene solution of the reagent was modified by the addition of a small proportion of nonanol. Experimental work included laboratory scale batch tests and small pilot scale continuous tests.A proposed extension of the process for the separate recovery of individual heavy lanthanides, yttrium, and thorium is described.INTRODUCTIONAt the Port Pirie uranium treatment plant of the South Australian Government, large volumes of "barren liquor", free from 'uranium, are at present run to waste. This "barren liquor" results from sulphuric acid leaching of Radium,Hill uranium concentrate, followed by separation of solid residues and removal of uranium from the clear solution by ion exchange. The mineral davidite, from which the uranium is derived, contains other potentially valuable components, notably vanadium, chromium, thorium, yttrium, scandium, and the lanthanides. These constituents are...

Jan 1, 1961

By S. P. Pereira

The mechanized mining cycle using loaders and shuttle cars had it speak in terms of usage in the mining industry during 1950 through 1960. In Brazil, this system is still used at underground coal mines in southern Santa Catarina coal basin. With the aim of investigating the benefits of a new mining scheme using the room and pillar method for these local mines, a computational simulator model was developed in order to investigate the mining cycle. This paper presents the methodology used to develop the simulator and the results that the simulation shows regarding impact of the proposed new scheme on mining productivity.

Jan 1, 2012

By Oliver Bowles

Sandstone, a widely distributed siliceous sedimentary rock, is the third most popular building stone in the United States. It is formed by the breaking down of preexisting rocks by weathering, subsequent segregation of the detrital quartz grains into discrete deposits by the sorting action of water or wind, and finally cementation of the quartz sand into a coherent rock. The homogeneity and resistance to weathering of the resultant sandstone make it suitable for exterior construction. Its excellent wearing properties explain its popularity for flagging and stair treads. However, quarrying and dressing methods and costs are adversely affected by the abrasiveness and hardness of sandstone especially as compared to limestone.

Jan 1, 1963

During the construction of storage caverns, and during their lifetime if the use to which they are put so requires, it is necessary to provide adequate ventilation to ensure the safety and comfort of the underground workforce. An analysis of likely contaminants during construction has indicated that where a large facility is situated in a rock mass of even moderate temperature climatic conditions are likely to be the limiting factor during most of the mining operation and atmospheric pollution when blasting is undertaken. Possible options for improvement are increased air flow, cooling of intake air and reduction of the heat source by altering the number and type of haulage units employed in the cavern. Local solutions are an alternative approach where heat problems are confined to a few specific locations

Aug 1, 1994

By T. Hart

Nuclear gauging is used world-wide in almost every industry. From mining and ore-grading to finished product, the metallurgical industry is one of the biggest users of nuclear sensors for inventory, process control, and quality assurance. This paper will discuss the basic theory of gamma transmission gauging techniques found useful in mining, milling and metal production. Techniques to be discussed are gamma transmission for level and density. A major new technique will also be discussed. This technique is called gamma backscatter. The uniqueness of this technology, how to apply and the differences between transmission and backscatter will be accentuated.

Jan 1, 2011