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By David Newton, Christian O’Keefe, Robert Maron, Jerin Russell, Paul Rothman, Dylan Cirulis

"The presence of unwanted coarse material in flotation feed streams negatively impacts both recovery and throughput of concentrator plants. The detection of this coarse material is a long-standing problem in mineral processing that has been poorly addressed by existing instrumentation systems. This problem has been overcome by the development of two new systems that detect in real-time the presence of coarse material in the overflow stream of individual hydrocyclones. They both use sensors mounted to the overflow pipe of the hydrocyclone and provide a robust and maintenance-free system measurement that enables corrective actions through operator intervention or automatic control strategies. One system is non-invasive and detects very coarse material 6mm or greater in size. The other system uses a wetted sensor and detects coarse material down to a lower size limit of approximately 100 um. Both systems have been commercially deployed. The systems will be described in detail. Validation data and typical plant data will be shown"

Jan 1, 2014

By Francois Mignard

With a limited global steel production growth, automotive application market shows interesting volumes and trends especially in emerging countries. The recent period has again enabled Siemens VAI to confirm a position amongst leading suppliers of new plants serving high-end steel production in particular for unexposed and exposed automotive material. With a series of recent plant references in operation and under construction, relevant answers to such sustained level of performances are highlighted along the downstream processes. Designed for a wide range of applications, Siemens VAI processing lines includes advanced technological and state-of–the art equipment, among them, Solid state laser welder, Pickling Tunnel tanks, Skin pass mill and Tension leveller, Side trimmer with dynamic width adjustment, and new generation of Automatic surface inspection systems. With a continuous aim of driving improvements, Siemens VAI has also developed Global Quality Monitoring solutions notably through advanced software which provide just-in-time warnings and assist steel makers in the daily operation of their lines. As lifecycle partner, Siemens VAI offers solutions and services in metallurgical expertise from metallurgical modelling, through physical simulation on rolling, annealing and galvanizing processes, and enables Siemens to accompany our customers along with their project definition till fulfilment of highest market requirements.

Jul 30, 2018

By Y. Pokhvisnev, S. Vandariev, A. Yatshenko-Juk, V. Valavin, V. Romenets

The technology of the liquid-phase reduction process known as Romelt was developed in the Moscow Institute of Steel and Alloys in 1979. The pilot plant was constructed at the Novolipetsky Steel Works (Russia) in 1984. Investigations into processing zinc-containing blast oxygen furnace dust and slag from the Lead and Zinc Works at the pilot Romelt plant proved the perspective of using this technology for processing zinc and lead-containing materials. In this article, the description of Romelt technology, basic technological information of trials at the Romelt plant using zinc-containing materials, compositions of charging materials, metal, slag, gas and dust are presented. The influence of flue gas composition on the composition of zinccontaining dust is shown.

Jan 1, 2000

By William W. Edgerton, Moussa Wone, David H. Corkum, Carlton M. Ray

"The DC Clean Rivers (DCCR) Project is a 25 year, $2.6 Billion court ordered project to reduce combined sewer overflows (CSOs) discharging into the Potomac and Anacostia Rivers and Rock Creek, and also reduce flooding in the northern areas of the District of Columbia. Like all massive infrastructure programs, DCCR faced technical challenges, management challenges, risks of cost and schedule overruns, procurement challenges, and financing challenges. While DC Water is no stranger to large capital improvement projects (CIP), this CSO Program represents a once in a lifetime event for the Owner requiring the assembly of a single purpose team to implement. Some of the DCCR Project team’s most successful accomplishments to date are attributable to its introduction of early contractor involvement (ECI) to thoroughly vet the work from the perspective of the future constructors, development of functional baselines to share risks that are difficult to price and reduce reliance on geotechnical baseline interpretation during tunnel excavation, and attainment of financing through Municipal Century Green Bonds based on using design criteria of a minimum of 100 year life for the structures to establish intergenerational equity and fairness. This paper will discuss these innovations in detail and provide some sets of recommendations for the underground industry on when and how to use different approaches to better manage projects of this magnitude. INTRODUCTION The District of Columbia Water and Sewer Authority (DC Water) is an independent multi-jurisdictional authority that was established in 1996. Its primary mission is to provide water distribution services to more than 640,000 residents in the District of Columbia (District), and sewer treatment and disposal to 1.6 million residents of the District, Montgomery and Prince George’s counties in Maryland and Fairfax and Loudoun counties in Virginia."

Jan 1, 2016

By G M. Taylor

The application of high technology to monitor and control fire life safety, critical functionality in tunnels and underground spaces generally has progressed at an ever accelerating rate over the past decade. Today these systems comprise some of the most complex and little understood aspects of the tunnel/underground facility construction industry, with this area being perceived as high risk comprising impenetrably complex ‘black box’ technology covered in blinking LEDs. This paper will seek to explode some urban myths and common misconceptions associated with such systems, providing its intended audience with a review of what all this technology comprises and where the real risks lie in its delivery lie.The author contends (and looks to support such contention via this paper) that by applying baseline project and risk management processes to the procurement of this widely misunderstood black box technology, the quality of the final outcome can be much improved, driving innovation, reducing both cost and significantly mitigating delivery risk.CITATION:Taylor, G M, 2014. Procuring control and intelligent traffic systems for major new build projects – avoiding pitfalls and maximising value, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 113–120 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By B. W. Steele

"Dofasco began operations in 1912 as a steel foundry located in Hamilton, Ontario. Today, Dofasco is a fully integrated mill that manufactures hot rolled, cold rolled, galvanized and tinplate steels. Customers include the automotive, construction, tubular, manufacturing, appliance, packaging and steel ser-vice centre industries. Raw steel production and purchased semi-finished steel processed in1994 was 3.5 million net tonnes. Dofasco employs 7300 people at its Hamilton facility.Environmental management at Dofasco is guided by its environment policy and associated commitments. This paper discusses Dofasco’s responsibility for its products as it relates to these commitments. Dofasco is com-mitted to:n the principles of sustainable development that require that activities be conducted in a manner that provides for the present without compromising the ability of future generations to meet their needs. These principles will be integrated into product design, manufacturing and business planning;n managing renewable and non-renewable resources through the responsible application of reduce, reuse, and recycle principles;n minimizing any potential impact of its operations and products on the environment, employees, customers and the community;n continuous improvement of the effectiveness and integrity of our environmental management systems;n developing understanding among all employees about their responsibilities, and assigning the necessary authority; andn meeting the standards set by relevant legislation and international agreements through participation with governments and the diligent application of economically feasible and scientifically sound methods and technologies."

Jan 1, 1996

By K W. Bian, Y M. Liu

Tongkuangyu Copper Mine is currently the only mine in China employing block caving. It comprises two large orebodies known as the No 4 orebody and the No 5 orebody. They are approximately 50° in dip angle, 80 to 240 m in width and 800–1000 m in strike length. The two orebodies are separated by a distance of 110–130 m. Production with block caving originally, ie Phase 1 project started at Tongkuangyu from the first undercut at a depth of 200–300 m below the ground surface and designated as Lift 810 m in late 1989 and has continued to the present. During the last 25 years Tongkuangyu has mined three lifts: Lifts 810 m, 690 m and 530 m. The previous two lifts utilised a slusher process with an annual designed production rate of 4 Mt. In this context the lift name represents the elevation of track haul level.The Tongkuangyu Phase 2 project serves for two lifts (ie Lift 530 m and 410 m) under the elevation of 690 m and the annual designed production rate is 6 Mt. Since the orebody is approximately 50° in dip angle, it is originally designed that production at Lift 530 m is comprised of one main extraction level and two auxiliary extraction levels in the footwall and undercutting is started from one end of the extraction footprint forward to another end, which is from north-east to south-west.Production at Lift 530 m started from March 2011 and reached to 6.39 Mt in 2013 and 6.9 Mt in 2014. Additionally, Tongkuangyu improved block caving processes and used modern mining equipment, which differ from the previous two lifts. Blastholes for undercutting and drawbell-preparation are now drilled using jumbos. The blasted ore is transferred to the underground crushing station via 10 t electric load-haul-dumps (LHDs) and then delivered to surface via a belt conveyor 3200 m long.Due to increasing ground pressure, a consequence of mining depth increase, stress abutment and inadequate support, significant damage occurred at the Tongkuangyu Copper Mine with production at Lift 530 m. This resulted in significant production delays and rehabilitation costs. A series of improvements have since been implemented including an advanced undercut sequence and increased ground support. All of these improvements have allowed Tongkuangyu to alleviate ground control issues, reduce operating costs and ensure safe production.CITATION:Liu, Y M and Bian, K W, 2016. Production at Lift 530 m of Tongkuangyu Copper Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 385–392 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By D. M. Neil

Road-headers are one of the most popular mechanized excavators used in mining and civil under-ground construction. These machines are primarily used in soft to medium hard rocks. This paper reviews the parameters associated with the application and operation of road-headers and presents a method for estimating cutting performance.

Jan 1, 1994

By Frank X. Bellini, Marc Saidman, Allen J. Hulshizer, Anthony J. Stewart

The cooling water system for the Seabrook Nuclear Station involves 10.25 Km (33,623 ft.) of 6.7 m (22 ft.) OD hard rock tunnels, over one third of which is under and terminating over 1.6 Km (a mile) out in the Atlantic Ocean. The major excavation is accomplished by two TBM's concurrently driving the intake and discharge tunnels which by mid-January, 1981, completed 92% of the excavation. This paper presents the case history of the excavation work and describes a computer program developed to evaluate major activities of TBM excavation on a shift-by-shift basis. Details and summaries of the production efforts are computer plotted in different forms to facilitate the evaluation of production performance, trouble spots and trends.

Jan 1, 1981

By F. Cadena

HIWASSEE Dam, now under construction by the Tennessee Valley Authority on the Hiwassee River, a tributary of the Tennessee River, will require aggregate for approximately 800,000 cu. yd. of concrete. Near the damsite deposits of natural sand or gravel are not available and graywacke, a rock that is found in abundance, suggested itself as a likely source of manufactured aggregate. Graywacke is a metamorphosed sandstone composed principally of a mixture of quartz (65 per cent), mica (25 per cent), and feldspar (10 per cent). Other minerals are present in negligible amounts. The rock varies in different parts of the quarry from very fine to a coarse grain containing particles of about 1/4 in. maximum size, although the bulk of the deposit is medium grain. Extensive tests showed that graywacke would be suitable as a source of both coarse and fine aggregates. The aggregate plant available for use at Hiwassee Dam consisted of the coarse-aggregate and sand plant used on the Norris project. The coarse-aggregate plant had also been used at Chickamauga Dam. Although most of this plant equipment is now in use at Hiwassee, the present flowsheet is not only different from that at Norris and Chickamauga but is also unique as compared to the flowsheet of the average crushed-stone aggregate plant. It is hoped that this paper will show the importance of proper arrangement of equipment if the optimum in flexibility and capacity is to be attained. FLOWSHEET Rock is loaded by 3-yd. electric shovels into 12-yd. dump trucks, which carry the rock to the primary crusher, a 42-in. Superior McCully gyratory unit set at 4 ¾ in. (Fig. 1). The primary crusher discharges directly onto a 42-in. inclined belt conveyor, which carries the product to a surge storage pile with a maximum live storage capacity of approximately 3000 tons. A concrete tunnel under this storage pile houses the feed end of a 36-in. belt conveyor (conveyor B) fed by a 36 by 66-in.

Jan 1, 1939

By A. W. JR. Whitaker

Introduction Within the last quarter of a century the Lake St. John-Saguenay valley has been converted from a quiet agricultural district to one of the important industrial centres in the Dominion. First there was the expansion -of the pulp and paper industry, and then, starting a little over ten years, ago, the development, in large .blocks, of the enormous hydro-electric power resources of the Saguenay river. Coincident with this power development, the world aluminum industry was rapidly expanding and looking for a new source of cheap power. This was found in the Saguenay valley-and so, in 1925, Arvida was established by the Aluminum Company of Canada as a location for one of the largest aluminum plants in the world. Arvida, an incorporated city comprising an area of some ten square miles, is ideally located on a more or less level plateau about 350 feet above the Saguenay river. Seldom has industry stepped boldly forth and carved out of Nature a community with full city status. The process usually goes through the steps of camp, village, town, and city, involving improper planning or lack of planning; all of which has been avoided at Arvida by starting out in the right way. While this community has only a population of approximately 2,000 at the present time, it is carefully planned for a population many times this figure. Streets, city parks, business and residential sections, have been definitely planned, and, with a City government, proper ordinances were passed at the beginning to ensure the building and maintenance of a model industrial community. As the crow flies, Arvida is about 35 miles due east of lake St. John, and 0 miles west of the St. Lawrence river at Tadoussac. From a shipping standpoint, it is well served by the Canadian National railways, with direct lines to Quebec and Montreal, and by ocean shipping facilities at Port Alfred, which is about 15 miles to the east on the Saguenay river and is served by the Roberval & Saguenay railway. The latter has interchange connections with the Canadian National at Arivda, and also operates a branch line into the city of Chicoutimi.

Jan 1, 1933

By Lee W. Saperstien

At the heart of the mining process are a number of basic and fundamental tasks whose regular and repeated performance constitute the mining cycle. As will be discussed presently, these tasks are the basic components of the mining system. Section 9, Production Operations, provides the mine designer and engineer with an understanding of these tasks and with sufficient design principles to allow this person to create an efficient mine system. This section is meant to be an introduction and adjunct to subsequent sections that describe specific mining systems. However, sufficient design information is included here for the independent design of mine systems that may not be described elsewhere or for subsequent verification of existing designs. For the purposes of this section, mining subsumes excavation; thus this material applies to any excavation process. Accordingly, this section is written in general enough terms to include both surface and underground mining. It may be used also for civil engineering excavations that often involve the same steps. Obviously, the actual procedures undertaken in any specific mining system will appear to be very different from those taken in any other system. This is certainly true when comparing surface with underground methods. Yet the fundamental principles are often the same. This segment is written to explicate the basics. Wherever appropriate, the section will suggest the differences between the application process to surface or to underground mining.

Jan 1, 2008

By Heinz Hofmann

In order to drive tunnels with low overburden in town regions, it is necessary to give a quantitative prognosis for the deformation of the underground as well as of the tunnel-lining and of its stability. These problems and their solutions are illustrated by the works for a two-track-railway-tunnel in Bochum (Ruhrdistrict). In this case the most important problems consisted in passing below buildings in a vertical distance to the fundamentals of only 3.20 m and a railway earthdam with rapid train traffic in a distance of 4 m under the dam. The results of measurements from other comparable tunnels and finite-element-computations were used to prognose the settlements on the surface and in the ground, their distributions and their development in time. To obtain these values at the site, a special system of tunnel driving was executed. The tunnel was excavated with the newest type of tunneling-machine from DEMAG, cutting an inclined front, immediately followed by a special temporary support of shotcrete and inclined steel-ribs. By using theoretical and empirical methods to assess the behavior of the tunnel and underground and by executing an optimal driving system in technical as well as economical aspects, the expected behavior, expressed in quantitative values, was almost equivalent to those received by control measurements.

Jan 1, 1974

By Dilip I. Patel, Jesus Schabib, W. Allen Mawr, Daniel A. Louis

East Side Access (ESA) will extend Long Island Rail Road into midtown Manhattan via 11 km of tunnels, a new terminal station and associated rail support facilities. The hard-rock tunneling in Manhattan will traverse under Park Avenue and some of the most historically and commercially significant real estate in the world. The soft-ground tunneling in Queens will traverse beneath Amtrak’s Sunnyside Yard and the Harold Inter locking, the busiest rail interlocking in North America. This paper details ESA’s program-wide geo-instrumentation monitoring system for obtaining, processing and presenting all geotechnical monitoring data. Data streams will be real-time, such as from automated total stations, and manually read, such as from optical survey instruments and handheld data loggers. All data will be input into a web-based Geo-Instrumentation Data Management System, which will be accessible to project stake holders via ESA’s intranet or via the Internet using remote access controls.

Jan 1, 2007

By A. Ignatieff

This is the second review of developments in coal mining engineering (see C.I.M .M. Transactions, Vol. LI, 1948, pp. 262- 264) and covers the period from October, 1948, to January, 1950. Mechanization The period under review was characterized by the intensive development of appliances providing for complete mechanization of coal-face operations. A variety of machines are being evolved or have already been placed on the market which embody the principle of 'continuous mining'. This trend can be observed in all coal producing countries. In the United States, two continuous mining machines have been developed for entry and room application and by the end of 1 949 were being used in a number of mines. These are the Joy Continuous Miner in which the coal is ripped from the face by means of multiple cutter chains, and the Jeffrey Colmol employing cutters on rotating arms for chipping the coal from the face. The Joy machine is made in tw6l models, 34-in. and 48-in. high and designed for a range of seam thicknesses from 3-ft. -t-in. to 4-ft. 6-in. and from 4-ft. 6-in. to 8ft., respectively. Some experience has been gained with this machine and accounts of its performance are already appearing in the technical literature. The Jeffrey-Colmol has a more limited range of working height. The first model, 38-in. high, was designed for seams about 4 feet in thick11ess but more recently the 28-in. low model has been placed on the market for seams 2-ft. 6-in, to 3-ft. 4-in. in thickness. Conventional mobile loading machines of the gathering-arm type are continuing to yield high production under suitable conditions, and improvements or modifications of the basic principle are embodied in new machines as, for example, the Jeffrey mobile (conveyor) loader with extensible (gathering-arm) head developed for conveyor mining.

Jan 1, 1950

By Gerald Sherman

LARGE part of the mining industry is still under the shadow of the depression, and unwilling to undertake changes in plant or methods of operation that require large preliminary expenditures of money. Certain metals command fair prices: nickel, tin, and molybdenum. The precious metals, gold and silver, have been given greater values by natural processes of economics or by proclamation, but are of so much less importance in industry, in total value, and number of men employed, that they have not greatly raised the average for the mining business. The increased value of gold which was established in 1933 has stimulated .the search for new deposits, and aided efforts to revive some of the old mines 'Where it is hoped to find quantities of marginal ore now become profitable. The higher price did not increase production very much for 1934, but two discoveries of major importance, and others yet to be proved, will help later. The two referred to are the Lupa gold field in Tanganyika Territory, and the Silver Queen mine on Soledad Mountain near Mojave in California. The first was recently discovered, and is being developed by the East African Goldfields, Ltd. Uncompleted explorations of the croppings early in the year had exposed for measurement and sampling to a shallow depth, three ore shoots as gregating 7400 ft. in length and 6 ft. in width, containing 0.375 oz. of gold per ton. In the Silver Queen. an ore-

Jan 1, 1935

By Scott Turner

AS IN OTHER lines of engineering, progress in mining was influenced during 1931 by the world-wide economic depression. Low-metal prices ? resulted in active efforts to reduce production costs of base-metal mines. Probably the chief factors in reducing costs were the greater efficiency of labor, due to better relations between management and workmen, to the scarcity of jobs, reduced wages in most base-metal mines, and to lower overhead expenses secured by drastic economies. The use of mechanical equipment continued to increase, due to more efficient designs and a better practical understanding of the applicability of such equipment to requirements. With one exception, there were no startling innovations in stoping methods, but there was notable progress in the better adaptation of mining methods. In the United States, no large new base-metal or silver mines came into production during the year. At a number of mines, output was curtailed, and operations were discontinued at several important producers. On the other hand world-wide interest in gold was stimulated, as evidenced by increased output from producing mines, the reopening of some old properties, and intensive prospecting for new deposits. Mining methods at several gold mines in the United States and Canada were modified or changed to obtain a higher extraction of ore or to meet the need for additional support of the mine workings at depth. Permanent record of improvements in mining practices has been made during the year by the Federal Government; the industry thus has available for its use more detailed information than ever before. This work was done through cooperation of the mining companies and their representatives with the United States Bureau of Mines, whereby many papers descriptive of practices and costs at individual mines have been published. The Bureau's program of describing methods and costs at the more important mines (those producing in excess of $100,000 annually) is nearly completed, but papers will be issued concerning such additional mines as may possess particular interest because of novel methods, exceptional conditions or operating results, and others to supplement reports already issued. In this way, an interesting record of the results of changing conditions, or innovations in methods, will be made available.

Jan 1, 1932

By N Belluz, L Johnson, N Wiwoho, P Manning

The Kucing Liar skarn deposit is located in the Ertsberg mining district, which also contains other skarn deposits and the Grasberg porphyry copper û gold deposit. The Ertsberg district is located in the province of Irian Jaya, IndonesiaÆs easternmost province. Mining development began in the Ertsberg district in 1972 with the mining of the Ertsberg deposit. Daily production in the district now averages about 230 000 tonnes of ore, with the bulk of the ore coming from the Grasberg open pit and the balance from underground mining of skarn deposits. During 1998, 45 218 additional metres of drilling were conducted to delineate and understand the Kucing Liar orebody. The deposit was first intersected in drill holes in 1994 and then was intersected in underground workings located about 1000 metres from the discovery drill hole in 1995. Initially, the two intersections were thought to be different orebodies but are now realised to be different parts of the same orebody. The Kucing Liar deposit consists of magnetite û copper û gold replacement and skarn mineralisation in favorable Tertiary and Cretaceous units. The deposit is approximately 2000 metres in length and averages about 200 to 250 metres in thickness. The width varies from 400 to 600 metres. Drilling in 1998 was directed towards delineating the deposit on its NW and SE ends and to determine its down dip extension. Reserves for the deposit at the end of 1998 stand at 320 million tonnes at 1.4 per cent copper, 1.4 g/t gold, and 5.3 g/t silver. Many important questions remain to be answered concerning the relationship of the Kucing Liar orebody to the major faults in the district and to the Grasberg intrusive complex which contains the Grasberg orebody. Continued exciting developments are anticipated as work to understand the deposit by drilling and geologic study continues.

Jan 1, 1999

By Bjorge, Guy N.

MINING method improve through the gradual process of evolution and in 1340 there were no marked outstanding innovations. On the other hand refinements of detail and betterment: in equipment design continued to progress. Among the most important changes have been the increased application of trucks and highway equipment, including tractors and bull- dozers, to open-pit mining as exemplified by Phelps Dodge's Morenci operations; the Mesabi iron range; and the Tri-State district. Mass or bulk handling contributed its part underground with slurhers and conveyors at Consolidated Coppermines and slushers at Climax; and in open-pit mining. conveyors found increased use on the Mesabi range.

Jan 1, 1941

By Jr. Schnakenberg

In 1986 the U. S. Bureau of Mines (USBM) embarked on a major research effort to develop technology that can substantially reduce worker exposure to face hazards simply by relocating the equipment operators to an area of relative safety. This reduced exposure mining system (REMS) research effort enhances the USBM ongoing health and safety research efforts to reduce and control dust and noise and to reduce accidents through training and better mining practices. This paper reports progress of the research that is developing and will demonstrate the technologies required for the computer-assisted tele-remote operation of continuous mining machines, haulage systems, and roof bolting machines.

Jan 1, 1996