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By John Garcia

THE presence of carbon de terre along the banks of the Illinois river was noted by the members of the Joliet and Marquette expeditions in 1673, and that may be referred to as the birthday of coal in the Middle West. The march of progress in the majority of indus-tries radiating from Chicago-one of the phenomena of history-is due in no small measure to this same carbon de terre and to the development and exploita-tion of the vast coal resources, which nature in a generous mood spread so lavishly over almost the en-tire state. The geological records indicate that coal-bearing rocks underlie three-quarters of Illinois, in-cluding 85 of the 102 counties and the entire area is estimated at from 36,000 to 42,000 square miles. Not all of the coal in this great area may be mined under the conditions existing today; producers are now taking the "cream" since industry demands the best quality and the lowest cost, thereby forcing competition among operators, which, in turn, com-pels the development of mines in those areas where the coal may be most readily .won, leaving the coal that is more difficult and expensive to mine to pos-terity. This is not such a bad arrangement, since the engineers of succeeding generations will enjoy the advantage of the experience of their ancestors, where-by they should profit and know how to mine a 2-ft. seam with as much economy and dispatch as we today work coal of thrice that thickness. During the period between 1830 and 1850, Illinois coal-mining progressed from the art of scratching along the outcrop to the development of small mines, mostly slopes, drifts and shallow shafts, but the real progress in the industry was coincident with the con-struction of railroads.

Jan 2, 1927

As the radical element has secured control of the various local printers' unions of New- York City, 250 magazines have temporarily suspended publication rather than grant their demands. The actions of. these local unions have been repudiated by the officers of the different inter-national unions, who are seeking in every way to carry out their agree-ments with the publishers. The charters of the local pressmen's and feeders' unions have been revoked by the international officers and new local unions are being formed. Members of the typographical union are not, as yet, directly affected by the strike, but many of them are taking "vacations," which accomplishes the same purpose as the strike but without the odium. The Engineering and Mining Journal, with true engineering spirit refusing to admit insuperable obstacles, is sending out a two-page printed market bulletin, together with two typewritten pages, making an an-nouncement of its predicament and giving brief items of mining news. Thus s brought home to the members of the mining profession in a very direct way the pernicious results of unrestrained control of labor organi-zations-by foreign and un-American elements. No sermon on this sub-ject is required, as the facts themselves are sufficiently eloquent.

Jan 11, 1919

By J. C. Harrison

When Exploraciones Eldorado, S.A. de C.V. finished their first phase of reverse circulation drilling at their La Trinidad property in Sinaloa, Mexico they began immediately with permitting and engineering activities. The first phase of drilling lasted four months and ended in April, 1994. The second phase of drilling ran from May through September of 1994. From May through December, 1994, Exploraciones Eldorado performed the permitting and engineering work for their La Trinidad heap leach mine. The mining permit was submitted to the regulatory agencies in February of 1995 and the first draft of the feasibility study finished one month later. The report outlines the permitting and engineering activities that took place during the second half of 1994.

Jan 1, 1996

By Staff

"The Weyburn Oil Field, located 80 miles southeast of Regina, Saskatchewan, was discovered by Central-Del Rio Oils Limited, in January, 1955. As of January 1st, 1959, the field had 357 wells capable of producing an estimated total of 45,100 barrels of oil per day.Highly portable, economical, drilling rigs are used to penetrate the pay at a depth of 4,400 to 5,100 feet. Presently, the complete drilling operation for an average field well, including drilling, coring, testing, and running casing, requires 12 days. Drilling procedures are conventional for a field of this depth and no serious problems exist. Central-Del Rio core the productive section of all their wells, which provides valuable information for well completions and reservoir studies. Production casing procedure is to set through the zone and perforate the productive inter-val. This was found advisable due to the lensing nature of the porosity and permeability throughout the reservoir, and to the high connate water saturation encountered in the tighter sections of the reservoir in the north and northeast areas of the field.Although a few wells in the field have produced naturally by flowing or pumping without acid treatment, it has generally been necessary to acidize the wells to make them commercial producers. To date, acid treatments appear to effect better stimulation of the limestone reservoir than fracturing treatments. Perforation sealing balls have been used as an aid in selectively treating all of the perforated interval.The majority of the field is on pump, producing at a low gas-oil ratio. The main part of the field has water-free production, with most of the water being produced in the north and northeastern area. Salt-water disposal is now available in the field through two disposal wells completed in the Basal Blairmore sand.The Midale Beds ""Marly"" and ""Vuggy"" zones form the principal reservoir, which is a stratigraphic trap, with the north and northeast edges terminated by a porosity and permeability pinch-out and the south-west and west edges bounded by water-laden porosity. There is no evidence to date of a gas cap. The reservoir apparently is producing on a fluid-expansion-type mechanism. The increasing water production in wells on the southwest and west edges of the field indicated water encroachment from these directions, and suggests some recovery energy may be available from this source.The total probable ultimate remaining recoverable reserves have been estimated at° 332,469,000 barrels of oil. Markets have not been able to keep up with the rate of development of the medium crude re-serves. However, it is felt strongly that substantial additional markets for Weyburn medium crude will be developed by the producers in the near future at realistic wellhead prices."

Jan 1, 1959

By Bing Li, Kai Liu, Yongcheng. Zhao

With the ongoing development of copper smelting technology, the improvement of environmental emission control and achieving an automated continuous copper pyrometallurgical process have become the key development goals for copper smelting. The double bottom blowing continuous copper smelting process combine bottom blowing smelting (SKS) and bottom blowing converting (BCC) process and fire refining as “three-connected furnaces” arrangement is a pyrometallurgical process independently developed by China’s ENFI which can continuously produce copper from raw material through to anodes. This technology can improve energy efficiency and reduce environmental emissions for the overall copper smelting and converting process. This paper discusses the engineering characteristics and production practice of the SDIC Jincheng Metallurgical Project, which operates SKS smelting and BCC converting process with “three-connected furnace” arrangement for the first time in the world. Advanced engineering concepts and tools were used to optimize the configuration during the project engineering stage. The operation shows that the process has good environmental performance, reduced energy consumption and high level of automation, which is a new choice for copper continuous smelting process. INTRODUCTION One of the most important developing trends for the overall copper smelting process is to develop a continuous operation. Continuous copper smelting can maximise energy efficiency in copper concentrate and make full use of the rich heat treatment system. Cold charge and a part of low-heat-generating materials, which are processing with additional equipment in traditional copper smelting process, can be processed with rich reaction heat in continuous copper smelting and converting process to achieve good economic benefits. Yuan and Wang (2017) noted that SKS+BCC copper smelting process can reduce the secondary SO2 emissions compared with discontinuous copper smelting process, which required transportation of melted matte by matte ladle and may cause secondary pollution. The continuous copper smelting process can also reduce the generation of intermediate cold materials.

Jan 1, 2019

By John C. Loretta

INTRODUCTION Organizations that regularly use project management services will almost certainly have their own views on the preferred systems and procedures. This chapter, therefore, describes Project Management for the personnel of groups not familiar on a regular basis with project management and deals with the basic questions that these groups can be expected to ask, such as: - What is project management? - Why is it needed? Project Management is the planning, implementation and monitoring of the Engineering, Procurement and Construction activities that are necessary to complete the project in the most economic manner. In the case of a crushing and grinding plant, completing the project would mean bringing it into full operat ion. Engineering is the design work for the purpose of producing drawings and technical specifications for Construction together with technical specifications and quantities for Procurement. Procurement is the arranging of con- tracts so that equipment, material and labour are brought as required to the construction site. Construction covers the on-site activities that bring together the components of Engineering and Procurement so as to arrive at a finished plant. Need & Cost Benefits Project Management systems are needed to allow progress and expenditures to be monitored so that any significant deviations from the plan can be identified and the appropriate corrective action taken. In this way, Project Management is able to give continual updated answers to the Owners broad questions. - What am I getting? - What will it cost? - When will it be ready? The need for Project Management is not always immediately apparent, a common belief being that the existence of the three components -Mining Company - Equipment Supplier - Construction Company - is sufficient to get the job done without a formal project management group. This trio

Jan 1, 1982

By J Euston

In the 1990s round flotation tanks were introduced as a result of the lower fabrication costs for larger cells. It was soon observed that round tanks held a number of further advantages over the traditional rectangular cells, such as better hydrodynamics, lower costs and reduced footprint per unit volume.In the last twenty years flotation cell sizes have increased almost exponentially and designs of 250 to 300m3 are a well established standard with plans for full scale pilot installations of 500m3. The option to install these large cells gives flexibility in circuit arrangements and allows efficient and economic matching of flotation lines with modern mill designs. The benefits of scale up are well known with reduced numbers of cells required, lower power costs per unit volume, etc. These benefits will be briefly reviewed with specific reference to the installation of 300m3 to 350m3 flotation cells at the Copperton Concentrator of Kennecott Copper in Utah, USA.The sophisticated techniques required to model these ‘supercells’ have led to a critical review of the fundamentals of flotation science and engineering. In addition to outlining the advantages of large flotation cells, this paper will review the science which supports, and occasionally challenges, the ongoing trend to larger flotation cells.

Aug 8, 2011

By K. N. Karparov

The classical limit equilibrium methods are suspected to be ineffective in predicting the potential for highwall failure in many instances in coal mines around the world. Slope engineers have for many years recognized a block thrust failure mechanism for slope failures, but little work had been done before 2000 to explain the actual mechanisms which must be responsible for the failure. The main reason for this is that limit equilibrium methods implicitly assume rigid blocks, and the resulting force equations must be satisfied everywhere simultaneously for them to have any meaning. This paper will show that the material involved in the slope failure is not rigid; indeed it undergoes considerable permanent deformation during failure. This observation allows the authors to treat the block boundaries independently, because they need not maintain a constant spatial relationship with one another, as is assumed in other methods. To enable analysis of this type the authors assume that the weight of the blocks is evenly distributed. This is reasonable, because the slope material is not strong enough to be self-supporting without some sort of constraint, or strong enough to be able to apply point loads to the surrounding material. The purpose of this paper is to extend the practical application of the analytical method developed from mechanism studies to provide an objective assessment of the risk of slope failure, and therefore guidelines for more stable slope designs. This work is based on studies carried out on two failures in an open pit coal mine in South Africa, and provides a methodology to assess the potential for failure more objectively than is possible with currently accepted methods, while at the same time remaining sufficiently simple to allow a ?back of the cigarette box? assessment by geotechnical engineers on site.

Jan 1, 2009

By J. Kuti

In room and pillar mining a large number of working points are arranged to follow a mining pattern. Geological and roof control problems can be overcome or their effect minimized by varying this pattern. Longwall mining on the other hand, fixes the mining pattern for anyone panel. This aspect of longwall mining leads to constancy, so that a well-conceived organization, ventilation, dust and roof control systems lead to daily repetition and subsequent simplicity of control. All the same, a fixed mining pattern calls for a very careful consideration and selection of design parameters. (Ref. 1.)

Jan 1, 1971

By Junji Shibata

As one of the effective usages of various wastes discharged in non-ferrous metal industry, the synthesis of hydrotalcite was carried out using aluminum dross as a raw material. Hydrotalcite is one of the inorganic anion exchangers and has layered structure of complex hydroxide. The removal of toxic metal ions such as As(III), As(V), Cr(VI) and Se(IV) with the hydrotalcite was investigated, and the removal properties were compared from the viewpoint of the anion exchange amount and exchange rate. Hydrotalcite can be obtained by a co-precipitation method from the aluminum dross and the waste MgCl2 solution discharged in an aluminum regeneration process. Slight amounts of SiO2, Al2O3, Fe2O3 and so on remain in the reaction product as an impurity component. Interlayer distance of the obtained hydrotalcite is about 0.3nm. Hydrotalcite changes to Mg-Al oxide by the calcination at 773K for 3h, and then hydrotalcite is formed again by a rehydration operation after calcination. The toxic metal ions are removed from aqueous solution by the anion exchange reaction in the pH region where toxic metal ions exist as the anionic species like AsO2-, HAsO42-,CrO42-, and SeO32-. The exchange amount is considerably concerned with the valence of anionic species and the size of anionic species. The removal of toxic metal ions were investigated from the engineering aspects such as the low concentration limit to be removed, the amount of hydrotalcite to be used for the perfect removal of toxic metal ions and so on.

Jan 1, 2006

By D. M. Rippley

THE St. Lawrence Seaway Project ranks with the greatest engineering undertakings of all time. A summary of major materials going into the construction of this project, shown in Table I, will assist in an appreciation -of this fact. These data relate to Seaway construction only, and it should be remembered that two large-scale power projects are in the construction stage on the St. Lawrence river concurrently with construction of the Seaway. A project of such magnitude as the Seaway would attract widespread interest even if it were being constructed in a remote area. The fact that it is located in a heavily populated and developed section of both Canada and the United States has done much to enhance this interest, and in many ways complicates the problems confronting the engineer in the design and construction phases. Many consider the St. Lawrence Seaway to be a new idea that has developed within the past decade - such is far from the fact, because the St. Lawrence River canal systems have existed for more than a century, and the Seaway Project is but a new, larger, and more efficient version of a continually expanding facility.

Jan 1, 1957

By J. L. Chakravatti

INTRODUCTION Mining of uranium does not differ, in many respects, from the mining of other metals; the ore must be drilled, blasted and transported in an underground or surface mine. Underground mining proceeds by the continuous development and advancement of a network of passages and rooms or stopes from which ore is excavated. As in most mines, rock conditions and ore grades in uranium deposits vary from area to area and between different mines. For mineral benefications of this ore in the mills, use is made of various chemicals, often with toxic or hazardous properties.1 As well as the need to control the more conventional hazards associated with any mining and milling operation, special care needs to be exercised in the mining and milling of uranium because of the radioactive nature of the ore. This requires that we examine closely the radiation hazard areas encountered in the mining and milling of uranium, with the broad overview of some of the basic facts in the radiation hazard control programme. To place the hazard in its proper perspective, we require recognition, evaluation and control of those factors arising in and from the workplace which may cause sickness, impaired health and affect the well being among workers or citizens of the community. The radiation environment in uranium mine is complex and variable. Although uranium ore is only mildly radioactive, it naturally contains a complex mixture of radioactive isotopes. Workers are exposed to external gamma radiation, to some beta radiation and to airborne radon, radon daughters and ore dust. All of these types of exposures warrant considerations in formulating control procedures but, in general, radon daughters are known to present the dominant risk. The basis of dose limitation in radiological protection is risk limitation. Long-term epidemiologic studies of United States uranium miners and that of miners in Czechoslovakia indicate that the incidence of lung cancer can be accounted for by a linear relationship with exposure to radon decay products.2 On the basis of this proportional exposure-risk relationship, a risk coefficient for lung cancer in the range of 1-5.10-4 WLM-1 during the total lifetime, has been estimated by UNSCEAR3 and other researchers. It should be noted that this risk coefficient includes the excess lung cancer risk from external gamma radiation in mines and from other carcinogenic chemical effects, if any, to which the miners are normally exposed during their underground work. It also takes into regard the possible synergistic influences. This paper reviews the occurrence of radiation and its control factors and the development of engineering design features for the environmental control at Denison Mine. NATURAL URANIUM SERIES Uranium is the most common element in the Earth's crust. It is widely distributed in nature in all rocks and is readily measurable in the sea. Hence, radon gas is universally produced in every part of the globe. Mining is patently confined to ores containing more than half a kilogram, or so, per tonne of uranium unless it is combined with other marketable metals. Uranium-238 is the first element in the uranium series. In all, there are 13 radioactive decay products of 238U (Fig. 1), ending up as a stable isotope of Lead-206. The whole basis of the radiological hazards associated with the mining and milling of uranium is dependent on the behaviour of these isotopes during each phase of the process.

Jan 1, 1981

By R. G. Dalbke

An increasing number of water pollution control systems are certain to be installed by many industries in the future because of new federal, state, and local government regulations, and because of the rising general concern about the deterioration of our water resources. Extensive engineering, some of it based on methods not yet developed, will be required if these new systems are to provide optimum pollution control. Capital cost, operating cost, and present and future regulatory requirements will be primary factors to be considered by engineers. This paper outlines procedures and gives examples of advanced engineering practices that have achieved efficient pollution control systems in the steel and nonferrous industries.

Jan 1, 1968

By V. C. Rogers

ALTHOUGH surveying at mining properties is fundamentally the same regardless of the method of mining, at Climax, due to the nature of the ground, the policy of advance development work, and extremes in climatic conditions, surveying practice has had to be revised to meet the specialized conditions of this particular type of mining operation. The company's mine is one of the largest underground properties in the United States. It has proved ore reserves of 275,000,000 tons, 60,000,000 tons of which have been broken. To date, 109,000 ft. of development drifting have been driven, as well as 40,926 ft. of development raising, 10,000 ft. of ventilation drifting and raising, 16,000 ft. of exploration drifting, and 206,000 ft. of diamond drilling. Normal production varies between 1.2,000 and 15,000 tons daily. Development work proceeds at a rate of 11/2 tons developed for every ton milled and with a development of 18,000 to 20,000 tons per day, the following crew is required to take care of mine and surface engineering

Jan 1, 1946

By C. E. White

The depletion of higher grade mineral reserves will accelerate the trend toward production from progressively larger and lower grade deposits. The discovery of adequate reserves of leaner ores will require the development of improved exploration techniques with a greater depth range. The principal challenges to the Canadian mining industry are to find the mineral resources required to meet fast growing world demand and to develop mining methods and equipment to ensure production costs which will strengthen our position in export markets in the face of in-creasing world competition. The challenges cannot be met without intensive efforts to attract more technical men to the industry and to improve their training.

Jan 1, 1967

By Robert J. Watters, Peter C. Kelsall, Joseph G. Franzone

Two separate studies investigated the compressive strength of basic igneous rocks and its relation to index properties such as porosity, density and soundrave velocity. The rocks tested were weathered dolerite from S. W. England and vesicular lavas from California. In both cases strength was affected considerably by porosity. In the dolerite, strength was also affected by fissures (microcracks) which were formed in the parent rock by shearing and later accentuated by weathering. While test results show that porosity, density and sound velocity are not reliable indices of rock strength, these properties are useful in interpretation of strength test results. Index testing can be used to classify samples according to similar behavior and to recognize the influence of fissures.

Jan 1, 1986

By Robert A. Siokler

Approximately 75 percentage of the earth's land surface is comprised of shale or shale-like materials. Shale itself is composed of the residue from an almost infinite variety of weathered parent materials which have undergone deformations ranging from intense to negligible. Under standard test procedures, shales exhibit a very wide range of physical properties particularly if the test specimen is subjected to a change in moisture content, when the original test values may vary from 0 to 100 percentage. It is this wide variation in physical property values compounded by its ubiquitous presence that makes shale such a problem material to engineers. In reviewing the literature relating to shale, it is evident that the "problem" has been approached from many directions. In order to understand why shales behave as they do, investigators have sought mineralogical, geological, chemical, electrical, and physical answers. Each study yields valuable academic information, but few contribute much of value to the engineer in the field. Many valid relationships between shale strength or competency and clay type, clay content, organic content, water content, grain size, cementation, density, porosity, etc, have been established. Yet it is very difficult to extend these understandings to the in situ condition with results that can be used by the field engineer. One major reason earlier work has not produced better information lies in the ambiguity of the definition of shale. It is apparent that no one laboratory parameter can be successfully used to provide sufficient engineering information to properly describe in situ conditions. For example; shale with swelling clays will produce low strength values provided: the swelling clay is in sufficient quantity, the clay is dispersed throughout the medium involved, and there is a low value of cementation. Shales with high unconfined compressive strengths have been found with very low shear strengths. Sandy shales often provide as many ground control problems as clay shales. Shales of similar nature may provide good roof conditions in one part of a mine yet in another part of the same mine the apparently identical shale may cause substantial problems. A clear need exists to classify shale in a manner which will enable the engineer to better predict the strength and durability of shale-like materials. Studies at the University of Missouri-Rolla (UMR) have focused on finding parameters which influence durability and competency, while being discretely discernible through uncomplicated testing. Initial research concentrated on distinguishing shale8 on the basis of standard physical tests such as: unconfirmed compression, triaxial shear, and slake durability. As results accumulated, however, it became evident that moisture content played a much greater role in determining competency than had been recognized previously. As a result the focus of the research turned to developing tests which would evaluate the influence of moisture on shale behavior. The above work then became a foundation for a second phase of investigation in which a suite of standardized tests were developed to provide a classification procedure. From this study five tests were identified as being critical: Moisture Activity, Atterberg Limits, Submersion, Unconfined Compression, and Shore Hardness.

Jan 1, 1986

By Yingda Zhai

The range of interburden thickness between coal seams in Datong Mining District of China is large. From mining operation point of view, the closer is between the two seams, the greater is the impact from the upper seam when the lower seam is mined. This impact is most notable when the two seams are ultra-close. In this paper the definition of ultra-close seams and its practical method of determination are presented. Based on the difference in strata thickness in the interburden and the concept of "yield depth ratio" which is defined as the yield zone depth in the interburden to the total thickness of interburden, the roofs of the ultra-close multiple seams in the Datong District of China were divided into 3 types: (1) false roof or rock partings in coal seam. This type of roof does not require special handling except mining them simultaneously as one single seam. The roof thickness is slightly less than 0.5 m; (2) completely broken roof. In this type of roof, the yield depth ratio is larger than (or equal to) 1. When the roof thickness is larger than 0.5 m but less than 2.0 m, the yield depth ratio must be smaller than 1; and (3) fractured roof. In this type of roof, the yield depth ratio is less than 1 while the roof thickness is larger than 2.0 m. In retreat longwall mining, if the gateroads of the lower seam are located under the gob of upper seam, roof bolting can be used in the 3rd type of roof. But if the 2nd type roof exists, powered supports must be used.

Jan 1, 2005

By Thomas R. Scotese, John L. Ackerman

The Hanging Lake Tunnel Project represents a major portion of the Glenwood Canyon Project, the last piece of Interstate 70 to be constructed. The project features twin bore, large span rock tunnels and six open cut portal excavations, all excavated by drilling and blasting. This paper presents descriptions of the methods used by the Owner and Engineer to control and monitor the drilling and blasting practices in the tunnels and in the portal areas.

Jan 1, 1992

By Noel C. Joughin

In making judgements on tolerable levels of risk in industry, and in all spheres of life, it needs to be understood that every action gives rise to risk. Without risk, nothing can be done. Without risk, no economy could be advanced. There is a strong tendency to emphasize the risk at work, but persons who are not working are exposed to a different set of risks. Often persons who are not working face greater risks than persons who are working. Simply, in being alive, one is exposed to the risk of an accident, the risk of contracting a disease, and an extremely diverse variety of other risks. According to the Health and Safety Executive of the UK, it is not possible to have a state of zero risk, because ?a state of zero risk does not exist?. Because zero risk is a physical impossibility, it is not possible to design for a state of zero risk in all engineering design. While the strategic target of achieving zero risk is laudable it does not provide any practical guidance to engineers as to what acceptable limits of risk should be. This causes a significant and real problem in the design for and the management of risk. Without meaningful guidelines, engineers, managers and the authorities often find themselves in disagreement. Thus, it has become essential to establish criteria for tolerable levels of risk and unacceptable levels of risk in order to design and manage engineering systems properly.

Jan 1, 2011