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By Herman Wotruba

Mercury emissions and other environmental impacts in small-scale gold mining are a world-wide problem. "Clean" or better: "Cleaner" technologies have -apart from being environmentally sound -to guarantee a higher income and better working conditions for the miners in order to have a chance for long-term acceptance. In small scale primary gold mining in several South American countries, a number of techniques have been adapted and improved so that they not only were accepted due to their efficiency and easy handling, but they could also significantly lower mercury emissions.

Jan 1, 2003

By E. C. Tarpley, H. M. Cooper, R. F. Abernethy

"INTRODUCTION The float-and-sink test 5/6/ is generally the first test used in determining the washing characteristics of coal. The simplest form of the test is that of using one solution of such specific gravity that the test sample is separated into ""float"" and ""sink"" fractions. In practice, however, a series of solutions is used, and the sample is separated into a number of fractions of a definite specific-gravity range. Analyses of a series of fractions of this type are often referred to as the ""specific-gravity analysis,"" and are of great value in the selection, construction, and operation of commercial washing equipment.The test is rather simple to use, provided a number of conditions are recognized and as many as possible held constant, such as:1. In laboratory testing, two types of solution are available -Aqueous solutions of calcium and zinc chlorides.Mixtures of organic liquids such as carbon tetrachloride, benzene, gasoline, bromoform, etc.2. Absorption of the solution by the coal,3. Solvent action of the solution toward the coal.4. Constancy of specific gravity during the test is affected by temperature changes, dilution, and evaporation.5. Personal technique of the test, such as the time the coal is in the liquid, rate of adding the sample to the liquid, stirring, time of draining, etc.6. Moisture content of the coal as tested."

Dec 1, 1947

By Stephen K. Pave1

Over 1,100 tons per day of Fluid Catalytic Cracking Unit (FCCU) catalyst is used worldwide. During the cracking reaction, catalyst is contaminated by deposited metals including nickel, vanadium, potassium, copper, iron, sodium, etc. To compensate for contaminants, a portion of the circulating catalyst inventory is withdrawn for disposal and fresh catalyst is added. The DEMETR process takes spent FCCU catalyst and removes a portion of the metal contaminants, enabling the refiner to recycle demetallized catalyst, thus reducing the solid waste from the refinery. Through August, 1993, the operation of one unit for one refiner has resulted in the recycling of over 7,500 tons of spent catalyst.

Jan 1, 1994

By G. Demi, G. Belardi, N. Shehu, S. Cico

The physico-chemical interaction between minerals such as olivine, chromite and serpentine and the ions most commonly present in solution, like Ca and Mg and flotation reagents such as EDTA and oleic acid was investigated. The study was conducted via release tests, electrophoretic measurements and microflotation of selected minerals coming from the Kukes deposit (Albania). The results were confirmed by means of beneficiation tests on various types of ores, from the Kukes (Kalimash), from Bulquiza area and from the Rizo deposit (Greece). It has been demonstrated that when Na-K Oleate is used as collector chromite, olivine and serpentine can be separated at pH = 2.5 and/or 5.5 employing EDTA (EthyleneDiamineTetraAcetate) on previously deslimed material. This approach ensures flotation concentrates with a Cr2O3 content about 50%, at a recovery in excess of 65%.

Jan 1, 2003

By David Sanscartier, Elizaveta Petelina, Alexey Klyashtorin

This paper provides an overview of the radiological risk mitigation approach applied by the Saskatchewan Research Council (SRC) for the remediation of 35 legacy uranium mine sites in northern Saskatchewan where uranium exploration and extraction took place in the 1950–60s. Mining activities resulted in an irregular increase of the gamma radiation dose rate (up to 18 μSv/h). The radiological objectives for the sites include a gamma dose rate at a spot (<2.5 μSv/h above local background), and the dose rate averaged over a hectare (<1 μSv/h above local background). These objectives are generally achievable at the impacted sites through the installation of shielding soil cover. This method may be impractical for site areas with rough terrain (e.g., steep slopes) and/or difficult access. A risk assessment approach is applied to determine if these areas can be safely left uncovered or if additional mitigation measures should be implemented. The risk assessment approach is based on two factors: (i) the ambient radiation dose rates collected through gamma surveys, and (ii) actual land use data collected through various surveys of activities of local community members at the sites. Exposure scenarios based on four land uses are applied to estimate a potential annual dose load for members of the public. The estimated doses are compared with the criterion of 0.3 mSv/a recommended by the Canadian Guidelines for the Management of Naturally Occurring Radioactive Materials (NORM). If the criteria are not satisfied, a mitigation plan is developed, and post-remediation gamma levels are modelled using GIS tools to evaluate the performance of the proposed mitigations. The proposed approach allows the team to optimize resources for the site remediation so that public exposure to NORM are as low as reasonably achievable after remediation.

Jan 1, 2020

By N. A. Eilertsen

Eastern Aroostook County, Maine, contains an enormous tonnage of manganese widely distributed in manganiferous sedimentary beds composed of hematitic shale, hematitic slate, and laminated siliceous carbonate rock. The bedded deposits range in thickness from several feet to over 150 feet. Manganese minerals that occur as silicates and carbonate are so minute that they cannot be concentrated by present methods of ore dressing. From a hydrometallurgical standpoint, the deposits can best be classified by amenability to acid leaching. The deposits of Aroostook County are in three geographical groups (see fig. l), designated as the northern, central, and southern districts. At least 13 deposits are known to occur in the latter district, which covers an Ewes about 8 miles wide and 15 miles long. The Littleton Ridge deposit, on the northern boundary of the southern district, previously examined by geologists from the State and Federal Geological Surveys on the farms of Donald H. Haggerty and David A. Abernethy, was pointed out in reports as being possibly the richest and largest in the southern district. The Bureau of Mines sampled this deposit by surface trenching and diamond drilling from May 1 to September 30, 1951. A total of 23 trenches was bulldozed, aggregating 5,355 linear feet, of which 8 trenches were sampled by cutting 185 channel samples over a linear distance of 1,820 feet.

Jan 1, 1955

By Baojun Zhao, Zhixiang Cui, Zhi Wang

"Bottom blown oxygen copper smelting process has been developed in Dongying, China by Dongying Fangyuan Nonferrous Metals Co., Ltd. in commercial scale. This is the first modem copper smelting technology developed in China with the advantages of high oxygen enrichment, low temperature and autothermal operation. Production capacity of more than 100,000 tonnes per year of copper has been achieved through a single bottom blown oxygen furnace with instantaneous feed rates reaching up to 90 t/h. The main features of the bottom blowing smelting process are that high grade matte (up to 72 wt% Cu) can be produced at relatively low temperatures with 2-3 wt% Cu remaining in the smelting slag. Analyses of quenched smelting slag show that significant amount of magnetite crystals are present in the slags at operating temperature which indicates that the operating temperature was much lower than the liquidus temperature of the slag. After four years operation this new technology has shown great potential for expanding production capability and energy saving. Process development continues on the first commercial scale bottom blown furnace at Dongying Fangyuan Nonferrous Metals and a larger bottom blown smelting furnace is under construction.IntroductionFlash and bath smelting technologies are the major processes used in modem copper making industry [l]. Ausmelt/Isasmelt using top blown and Noranda/Teniente using side blown are typical and common bath smelting technologies. In 1980s-1990s Hunan Shuikoshan Mineral Bureau, jointly with China Nonferrous Engineering and Research Institute (now China Enfi Engineering Corp.), developed the concepts of the bottom blown oxygen processes for both lead and copper smelting [2]. After the pilot test on 3000 ton copper per year scale in 1991, it was not progressed to industrial scope."

Jan 1, 2013

By V. E. May

Has your organization adopted Six Sigma as part of their Performance Improvement strategy? What about Lean manufacturing or Lean Six Sigma? If you already have any of these business process improvements in place where will you go next? In this article we will focus on transforming your organization beyond Lean Six Sigma to the next level of performance. In the future companies can take another quantum step forward by combining Lean Six Sigma with advanced Root Cause Analysis (RCA). The value of taking this natural progression on the way to achieving new levels of organizational excellence is presented.

Jan 1, 2011

By Geo. E. Cole

A GREAT deal of time and energy is now being devoted to the study of post-war reconstruction and rehabilitation, in spite of the fact that as yet we have not won the war in which we are presently engaged. If you feel that the study of post-war problems takes our thought away from the problem immediately before us, you may well query, "Well! What has all that to do with winning the war, our most urgent problem today?" The answer has been given by Principal James of McGill University, Chairman of the Cabinet Committee on Reconstruction: "Reconstruction is something which must be thought of in advance, partly for the purpose of recognizing exactly the influence of war-time activities, controls, and regulations on the post-war Canadian scene. Many people are acutely interested in this great problem. It is not that they are not interested in the war itself, or epochal events that are taking place from day to day. They have a vision of that future which they hope will be Canada&apos;s, and this vision inspires them to even greater efforts at the present time". The trend of events would indicate that changes, economic and industrial, after this war will be greatly out of line with those that followed previous wars in history, for the present struggle has involved every nation in the world. In the peace that will come, every engineer will have a task in bringing the most desirable order out of the most distressing chaos. We certainly are living in a changing world; we are witnessing geo-graphical and economic readjustments that no other generation in world&apos;s history has ever witnessed. And there is an opinion gaining strength in our Dominion, as in other lands, that after this war we shall live in a world in which our process of thinking and our very way of life will have to undergo drastic changes to cope with the new order of things. Sadly our world of today has had to revise the sublime vision that nation shall not lift up sword against nation, while salvage operations continue to beat ploughshares into tanks and the peaceful pruning-hook into a weapon for the deviltry of the commando.

Jan 1, 1943

By Kazuhide Nakaniwa

In this research, we devised a measurement method using total stations (TSs) which have ?the Baum? which is a concentric circle reticle, as substitute for crosshairs. The Baum owes its name to the similarity between the concentric circles and trees (Baum in German). By setting one circle on both of edges of cylinders, operators can set their sights on points on the center line of the cylinders, and also can measure positional coordinates of the points. Also, by measuring two different points on the center line, operators can measure the position and tilt of the axes of the cylinders. Furthermore, we developed a pile driving navigation system. Foundation piles are used for various structures, and their forms are generally cylindrical. Especially, although it is difficult to drive tilted pile foundations, their usage are expected to expand due to their high earthquake resistance. Yet, a method to accurately measure the tilts of piles has not been established. However, we proved that operators can obtain adequate accuracy to control foundation piles through the measurement experiment using this system. Using this system, the information of the pile is measured using a TS, transferred to a PDA, and displayed from the operator?s view of the piling machine.

Aug 1, 2013

By J. P. Kerr, W. H. Cordell

Conditions in the oil and gas industry in Indiana were about the same in 1935 as in 1934. This is especially true of the old Trenton area and the Harrison County area where production was steady and almost no exploration and development took place. The past year has seen an increase in drilling activity and a decrease in oil and gas output in southwestern Indiana. In the state, 224 wells were completed in 1935, of which 48 were oil wells, 61 gas wells, and 115 dry holes. A few of these were old gas wells deepened to oil horizons. Twenty-six wells started during 1935 were not completed by Dec. 31. Approximately one-half the wells drilled were within proven areas. A relatively large number of wildcats, especially in Daviess, Pike and Gibson Counties, were in search of new gas supplies to supplant the diminishing resources in those counties. The decreased production of gas was due largely to the fact that existing supplies declined more rapidly than new fields could be brought on. The Alford field, in Pike County, which produced the bulk of the supply in 1934, was called on to do likewise in 1935, but was unable to respond sufficiently to keep up the yearly production for southwestern Indiana. During the last half of the year, the Oaktown field, Knox County, was connected with one of the principal pipe lines of the state, which helped to keep gas production above an unusual low. The decline in oil production was due almost entirely to proration during the first eight months of the year. The proration affected Daviess, Pike, Gibson, Sullivan and Vigo counties, which produce about three-fourths of the total for the state. After proration was lifted, the wells never quite reached the conditions existing before proration. The average daily production per well in Indiana is less than two barrels. The outstanding development in Indiana in 1935 was the drilling in the Oaktown field immediately before and after the laying of the 6-in. pipe line to the field. Almost without exception the wells came in with an open flow of two to four million cubic feet. At the end of the year, 26 wells were connected to the pipe line. Development of this field will

Jan 1, 1936

By J. P. Kerr, W. H. Cordell

Conditions in the oil and gas industry in Indiana were about the same in 1935 as in 1934. This is especially true of the old Trenton area and the Harrison County area where production was steady and almost no exploration and development took place. The past year has seen an increase in drilling activity and a decrease in oil and gas output in southwestern Indiana. In the state, 224 wells were completed in 1935, of which 48 were oil wells, 61 gas wells, and 115 dry holes. A few of these were old gas wells deepened to oil horizons. Twenty-six wells started during 1935 were not completed by Dec. 31. Approximately one-half the wells drilled were within proven areas. A relatively large number of wildcats, especially in Daviess, Pike and Gibson Counties, were in search of new gas supplies to supplant the diminishing resources in those counties. The decreased production of gas was due largely to the fact that existing supplies declined more rapidly than new fields could be brought on. The Alford field, in Pike County, which produced the bulk of the supply in 1934, was called on to do likewise in 1935, but was unable to respond sufficiently to keep up the yearly production for southwestern Indiana. During the last half of the year, the Oaktown field, Knox County, was connected with one of the principal pipe lines of the state, which helped to keep gas production above an unusual low. The decline in oil production was due almost entirely to proration during the first eight months of the year. The proration affected Daviess, Pike, Gibson, Sullivan and Vigo counties, which produce about three-fourths of the total for the state. After proration was lifted, the wells never quite reached the conditions existing before proration. The average daily production per well in Indiana is less than two barrels. The outstanding development in Indiana in 1935 was the drilling in the Oaktown field immediately before and after the laying of the 6-in. pipe line to the field. Almost without exception the wells came in with an open flow of two to four million cubic feet. At the end of the year, 26 wells were connected to the pipe line. Development of this field will

Jan 1, 1936

By N. Paas

Diesel powered equipment has been operated in underground coal for more than 50 years. According to the Mine Safety and Health Administration (MSHA), there are approximately 3,000 diesel units operating in underground coal mines in the United States. This number is expected to reach 5,000 diesel units in 250 coal mines by the year 2000. Also, there are approximately 5,000 diesel units operating in metal/nonmetal mines such as trona, potash and salt mines: and more than 3,000 diesel units operating in Canada. This increased popularity of diesel powered equipment over trolley wire, electric trailing cable or battery powered equipment is because of improved safety, greater mobility, higher productivity and increased power of diesel equipment.

Jan 1, 1997

By Pierre Laliberté

L?utilisation de plusieurs nouvelles technologies et systèmes de contrôle visant des économies d?énergie dans une exploitation minière pourrait laisser croire qu?il suffit d?additionner les économies potentielles de chacune de ces technologies pour en évaluer l?économie totale. Une addition simpliste des pourcentages d?économie pourrait, dans certains cas, dépasser 100%, ce qui est évidemment totalement incohérent. Les LMSM-CANMET sont à réaliser une étude dont les résultats serviront à estimer l?influence de certaines technologies et systèmes de contrôle visant des économies d?énergie et à évaluer l?impact des unes sur les autres. En outre, un modèle de simulation est en cours de création afin d?évaluer les gains incrémentaux liés à l?application d?une série d?innovations dans une exploitation minière. La présentation fera le point sur l&apos;état d&apos;avancement du projet en plus de soumettre quelques exemples.

May 1, 2007

By O. Leuangthong, E. Schnetzler

"The McMurray formation in the Athabasca oil sands deposits of northern Alberta is part of the world’s second largest proven crude oil reserves. The formation is characterized by stratigraphic layers that correspond to three different depositional environments: Marine, Estuarine, and Fluvial facies. Resource estimation for oil sands has traditionally relied on polygonal and inverse distance schemes. These techniques are simple and straightforward in practice, but they do not permit reliable uncertainty assessment. This paper describes the modelling of the McMurray formation using modern geostatistical techniques.Geostatistical modelling should be performed within homogeneous geological facies. The methodology for geostatistical simulation within each of the identified facies involves: 1) assessing the most appropriate stratigraphic transformation for optimization of the correlation structure; 2) determining representative distributions with declustering and debiasing techniques; 3) modelling spatial continuity of the bitumen grade, fines grade, water saturation, and other petrophysical variables; 4) performing estimation and cross validation as checks against simulation results; 5) performing simulation for uncertainty quantification of bitumen and fines grade; and 6) model checking of simulation results against the input data, and comparisons against the kriged models. These steps are described in detail. The application of these models for uncertainty quantification in support of resource classification is also discussed."

Jan 1, 2006

By A Duran

When dealing with rocks in the geotechnical profession, a common activity involves providing an estimate of the intact strength. The tactile approach and descriptions of strength that apply to soils is well documented, can be readily checked through the use of a pocket penetrometer and are known to provide reliable estimates of strength. Moreover, although different soil strength classification systems are present, the bounds between classification classes are compatible across almost all documented classification systems. However, this is not the case for rock strength materials. There are numerous systems within the literature, some with different concepts, and almost all have different bounds to each strength classification. In this paper, the author presents seven classification systems for estimating intact rock strength and highlights issues in their implementation. Example cases are presented to discuss the typical concerns confronting field strength estimates.CITATION:Duran, A, 2014. Comparison of field estimated strengths, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 101–106 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By ?. S. Yusupov, V. P. Isupov, N. Z. Lyakhov, A. G. Vladimirov, S. A. Kondratiev

"Considering the shortage of lithium reserves, the desirability has been shown of studying the possibility of processing into spodumene concentrates the concentration tailings and low-grade ore reserves at Transbaikalian Mining and Processing Project (ZabGOK). The mineral and chemical composition and the particle size distribution of the mineral feed, separability and recoverability of spodumene have been studied, forming the basis for the development of a concentration process and flowsheet for the studied mineral resource. Prospects have been established for impact ore grinding in a disintegrator, the efficiency of mechanochemical processes has been shown in the separation of quartz and feldspar and the recovery of lithium from concentrates.INTRODUCTION Lithium is widely used in various industries - nuclear power engineering, defense technology, power generation, ceramics, special-purpose glass and other technologies. The increasing demand for lithium and its compounds (lithium carbonate and hydroxide) for use in the manufacture of high-tech products (lithium-based materials for chemical sources of electric power and electrochemical energy) explains the need for establishing a sustainable raw material base (Mohr et al. 2012; Moores, 2007). The main sources of lithium are spodumene pegmatites (Vladimirov et al. 2012; Garret, 2004), brines (salars), and hydromineral materials (Garret, 2004; Zeng and Liu, 2009; Kotsupalo and Ryabtsev, 2008). However, in view of the absence in Russia of extractable hydromineral resources of lithium, the practical significance of spodumene ores remains decisive. Russia controls some of the world’s largest reserves of rare-metal pegmatites holding over 8 million tons of Li2O: approximately 7 million tons on the Kola peninsula and 1 million tons in the Sayan mountains. The main lithium mineral in pegmatites is spodumene LiAlSi2O6 containing 8.1% Li2O. It can be efficiently recovered by gravitational concentration and flotation. However, most of the deposits are located in remote areas and none is currently developed. In this connection, special research is focused on technogenic raw materials, which are increasingly seen as a solution to the resource base problem (Chanturia, 2008, Kurkov and Kotova, 2007)."

Jan 1, 2018

Introduction Agrico Mining Co.&apos;s Florida mining division has three surface mines and employs nearly 700 workers. The division produces some 6.3 Mt (7 million st) of phosphate rock annually. It is a good business. And Agrico has made it better by making it safer through a new approach to mine safety. In one year, Agrico - the second largest phosphate mining company in the US - recorded a stretch of one million manhours without an accident. That same year, the direct cost of accidents dropped to $9137 from a previous five-year average of about $50,000. Together with Don Roe, division manager of safety and security, Division General Manager Don Morrow made 1981 a watershed year for safety at Agrico. Morrow called on consultants from Safety Management Services of Du Pont&apos;s Specialty Services division to strengthen a safety program that was already better than average. From the late 1970s and into 1981, lost-workday cases (LWCs) were costing Agrico an estimated average of $22,000 each. And they were occurring with alarming frequency. In 1977, the company recorded six LWCs at an incidence rate of 0.64. This was followed by a jump to nine cases in 1978. In 1979, both occurrences and the rate increased - 10 LWCs at a 1.19 rate. The number of LWCs decreased to seven in 1980, with a rate of 0.71. Agrico instituted a far-reaching safety program in 1981, which began to take full effect in 1982. LWCs dropped from five in 1981, to three in 1982. And the direct cost plummeted from $110,346 to $28,828. In 1983, the mines recorded only one LWC. Its $9137 cost represented a reduction of $101,209 since the Safety Management Services of Du Pont had been called in. Through early 1984, the LWC incidence rate at the facility&apos;s three mines, phosphate drying plant, and transportation department was down to 0.26. This is 84% lower than the 1982 mining industry average, making it the safety leader among all Agrico companies, including its chemical plants. New Approach Agrico had the basics of a safety program in place when the Du Pont consultants arrived. But Du Pont suggested changes in responsibilities and company philosophy that formed the foundation of

Jan 1, 1985

By Samuel Taylor

IT is customary for the president of an engineering society, in his annual address, to describe either some engineering problem with which he has beer connected or to review the work of the society during his administration. My first thought, this being the sesquicentennial year of our nation, was to review the advance in coal mining for the past fifty years, during which period I have been more or less intimately con-nected with the bituminous coal industry, and have personally witnessed most of the great changes which have occurred in methods and machinery used in the production of coal, but preparation of the requisite address would take more time than could be spared to prepare it, and its presentation would consume so much time that it .would not be suitable. The new arrangement providing for giving the presi-dent&apos;s address at the business meeting makes it more .appropriate to review the work of the Institute during the past year, together with some suggestions which appeal to me as being of advantage to the future wel-fare of the Institute, which I will try to do briefly. The work of the business office has been reviewed in the Secretary&apos;s report and it will not be necessary for me to dwell on it. Suffice it to say, it seems to be going along very well. Additional work could be done which would be to the advantage of the Institute, if we had the money with which to defray the necessary ex-pense incident to it, but I will refer to this again later. I would be derelict if I did not refer to the splendid work of the Secretary and the Assistant Secretary. Keeping in touch with all the sections, which number now about 26, and affiliated student societies which number 40, besides special committees, and represent-ing the Institute on various boards, provides work enough to occupy the Secretary&apos;s time almost exclu-sively. In addition to this the Secretary and the As-sistant Secretary have the work of editing and publishing the TRANSACTIONS of the Institute; the issuing of the magazine, MINING AND METALLURGY, in the splendid manner in which it goes out to the mem-bership is no light task and I think they should receive the commendation of the membership for this work.

Jan 3, 1927

By Frederick B. Kuhnow

Harmonic energetic delamination of T2 building is being considered for demolition at a formerly known atomic lab. The T2 building is within a containment structure that is under a negative pressure of -49 Pa (-0.2 inches of WC) so that no remaining radioactive material is leaked out. The T2 containment enclosure is a portal frame-type system that spans east/west over 35.05 m (114’-11 7/8”) and spaced 2.9 m (9’-6”) apart. The west side of the portal frames is supported by a 64 cm (2’-1”)thick concrete wall which is backfilled to the west and open to the T2 basement to the east. The east side of the portal frames is supported by a 61 cm (2’-0”) thick concrete wall that is backfilled to the east and open to the tank farm vaults to the west. A concrete slab-type footing supports both the east and west walls. Transverse walls provide lateral support for the walls as part of the original design. The west wall has an elevated slab that provides further stiffening of the concrete wall between the transverse walls.

Jan 1, 2017