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By A. McLean, M. Iwase, K. Wakimoto, K. Katogi

For many decades control strategies have been based upon samples taken from liquid steel, molten slag and gas phase as well as from solid products. Because of recent developments in the areas of dynamic control models, artificial intelligence and expert systems, there is an increasing incentive to develop diagnostic sensors, which permit in-situ rapid determinations of concentrations of various elements in molten steel. In this paper, an overview is given on recent developments in the areas of sensors for use in ferroalloy and steel production. Particular emphasis will be given on (i) innovative application of sensors for on-line determinations of dissolved elements, Si, P, N, H and Cr in molten iron and ferroalloys, (ii) evaluation of inclusions in liquid metal and (iii) rapid determinations of slag compositions.

Jan 1, 2004

By Rolf B. Pedersen, Ana Filipa Marques, Ingunn H. Thorseth, Ingeborg Okland

"Deep sea mining of polymetallic sulphides will change the physical and chemical conditions at the seafloor by creating scars when sulphides are removed, and potentially also by deposition of mine tailings at the seafloor. These changes will impact the existing ecosystems at the seafloor in and around the mined areas. Seafloor Massive Sulphide deposits that have been exposed to oxic seawater weather into Fe-metal-oxyhydroxides. However, the rates of weathering and release of heavy metals and other toxic compounds to the environment from freshly exposed sulphides in a deep-sea environment are not well studied.During a cruise to the Arctic Mid-Ocean Ridge in the Norwegian-Greenland Sea in July 2014 we will initiate in-situ experiments investigating the microbiological and geochemical processes involved in the weathering of freshly exposed massive sulphides deposits in a natural environment. This will be done by creating scars in naturally occurring sulphide deposits and by deploying weathering experiments at the seafloor. The sites will be revisited and re-sampled in 2015. The mobility and fate of heavy metals will be one of the main concerns of the study as well as constraining the time it will take for exposed sulphides to return to the chemical state present prior to mining. In this presentation we will present the experimental framework and the preliminary results from the July 2014 cruise. This project is part of the EU funded MIDAS (Managing impacts of deep sea resource exploitation) project."

Sep 1, 2014

By J. A. Woolf, A. P. Towne

"INTRODUCTION A considerable part of the metallurgical work of the Precious Metals Section comprises ore-testing experiments on ores selected as representative of various mining districts on areas. Projects authorized by the Bureau and assigned to the Precious Metals Section generally include only those ores or tailings in which the precious metals are the main valuable constituents; however, there are also included ores that contain strategic or critical metals in addition to the precious metals. The recovery of strategic and critical minerals is the most important phase of the treatment of this latter class of ores. However, if a considerable percentage of the precious-metal content of such ores can be recovered without complicating the flow sheet too much, it may be possible to treat an ore for the recovery of strategic or critical metals that could not otherwise be treated at a profit.Standard testing procedure involving cyanidation, amalgamation, gravity concentration, and flotation, or a combination of these methods, is employed in the greater part of this work. However, as the complexity of the ores furnished for this work has increased, it has been necessary to include special applications of standard procedures in many instances, Standard methods of conducting tests and the purposes of the work as a whole have been discussed in previous reports 4/ of ore-testing studies. In the present report, whenever it has been necessary to apply some special phase of standard treatment, this has boon explained in detail in that particular section of the report."

Aug 1, 1944

By Amir Zavichi

Today, with the necessity of timely, on-budget and high quality completion of projects, proper use of construction equipment is essential to ensure project success. Construction equipment places a large monetary burden on the project and if not utilized efficiently, it can result in economic losses. Cranes are one of the most important and expensive operational devices on construction sites. They play a central role, and often activities that rely on crane services fall on the project?s critical path. Currently, material-handling scheduling is done by the crane operator or by an on-duty superintendent using his/hers personal judgment, making the process manual and timeconsuming. Thus, developing an optimal schedule, which considers different dynamic constraints in construction job site, may not be possible based on the current practice. This leads to longer operation times and a negative impact on project cost. This paper presents the latest results of an ongoing study, which aims to design and implement a nearreal time crane operation decision support system to be utilized directly by the crane operator or as an aid for the superintendent in scheduling optimal operation services. This system has several advantages such as maximizing the efficiency of crane operations, guaranteeing the best operation possible to reduce the crane?s travel time, reducing crews and equipment idle time, and minimizing the dependence on subjective human judgments.

Aug 1, 2013

Mining steeply dipping coal seams is a difficult task in the mining industry. Prior to 1996, fully mechanized longwall mining methods along the seam strike direction were tried in China and other countries. Due to its larger coal reserve in steep seams, China made more but still limited progresses on mining in such seams than the other major coal-mining countries. In the last two decades, accelerated research efforts have been made to improve the mining technology in steeply dipping coal seams. Based on these works, a dynamic model of ?R-S-F? system under asymmetrical constrains in mining steep seam is established and the theory of strata control and hazard prevention begin to be formed. The key technologies for mining steep coal seams include: global and regional strata control methods in longwall face, methods for the longwall face machines to sustain static and dynamic loads, and flexible protection technology. These theory and technologies have been successfully applied to mining of steep coal seams of varying thickness and hardness, with hard and soft roof and floor, and with high potential of spontaneous combustion in China. In the recent years, the technology has been introduced to Russia, India, Uzbekistan and other countries where steep coal seams are mined.

Jan 1, 2012

"The effective thermal conductivity (ETC) is one of the most important thermo-physical properties of porous media. Due to the lack of higher precision influence of temperature on thermal conductivity, we took 6 groups of experiments on rock samples (including igneous rock, sedimentary rock and metamorphic rock) under different operating temperatures from 20? to 50? by 7 acquisition points. The general equation of thermal conductivity drives the value of it increasing along with the decreases of the temperature. While in our experiments, it is easy to find a singularity among them for each sample. The experimental investigations we attempted to observe and interpret the alteration mechanism. According to the Heat Capacity Theory in solid state physics, this research gives the explanation about the “singularity” from 3 understanding of specific heat, average free path, and thermal conductivity. Our research divided the condition of the rock thermal conductivity into 3 different types. INTRODUCTION The effective thermal conductivity (ETC) is one of the most important thermo-physical properties of porous media(Huang & Han ,1988; Peierles ,1955). This parameter is necessary for analysis of heat transfer(Vaferi et al, 2014;Hans-Dieter & Rudiger,2003). It’s well known that a general equation for ?(T) was set by Sass et al. (1992) which based on the coupled effect of composition and temperature on the thermal conductivity(Jesse et al, 2013; Mongelli et al,1982).The equation was further successfully verified for other rock (Zumrud et al,2010;Abdulagatova et al,2009;Seipold& Huenges,1998).Thermal conductivity is also related to other physical proper ties of porous rock, such as thermal diffusivity, heat capacity(Brettmann et al,2011;Abuel-Naga et al,2008). It is well known that ETC and other thermo physical properties of rock materials are affected by various factors, such as temperature, pressure, mineralogical composition, porosity, stratification, size and shape of the components, and nature of pore fluid, etc. (Tiedje & Guo, 2014; Touloukian et al,1970).The understanding of heat transport processes still requires the knowledge of thermal properties of rocks."

Jan 1, 2015

Ferrous and Nonferrous Physical Metallurgy Established as a Division April 26, 1918 T A Read, Chairman O T Marzke, Past Chairman J H Jackson, Senior Vice-Chairman David Swan, Vice-Chairman D C Johnston, Secretary-Treasurer AIME, 29 West 39th Street New York 18, New York

Jan 1, 1960

The following paper describes the refining practice for the production of lead, silver and gold at the works of The Broken Hill Associated Smelters Pty. Ltd., Port Pirie, South Australia.The refinery is situated on the wharf frontage and is built parallel with it. The refinery occupies an area of approximately 3380 square yards. (Fig. 8)There are two buildings, one containing the softening and de-silverising sections, measuring 225 ft. x 57t ft., while the other building, which measures 225 ft. x 90 ft. covers the de-zincing, lead moulding, retorting, cupellation, and dore parting sections. (Fig. 1)The retorting, cupellation, and dore parting sections are completely isolated from the rest of the plant by strong small-mesh wire gratings welded to steel uprights. The dore parting plant and generator room are further isolated by a brick wall, built up to the roof. The two main buildings are steel structures, with outer walls and roof of "Robertson" corrugated sheeting; the side and end walls are open for some distance above the ground, and this, coupled with the high roof which is 50 ft. from ground level, ensures the free access of air and light. Conditions are such that operators work in a clear atmosphere.

Jan 1, 1937

By Nicholas G. Theofilos

The Bahamian economy weathered the worldwide recession of the last few years better than most developing countries. This was mainly owing to the ties between the tourist industry of the Bahamas and the U.S. economy. The mineral industry played a minor role in the country's economy. The chief mineral exports included an increasing amount of petroleum products horn the country?s 500,000-barrel-per-day refinery, steel pipe, salt, and aragonite. A 60,001)-barrel-per-day desulfurization facility was completed by Bahamas Oil Refinery Co. (BORCO) in Freeport. The project included vacuum gas oil desulfurization, hydrogen and sulfur recovery, steam generation, water desalinization, and offsite facilities.

Jan 1, 1980

By D Frantzos, J J. Cotter, H Tammemagi, J B. Codrington, J Kaasalainen, A C. Webster

"Exploshres Technologies International (ED) is developing an instrument called ROCSCAN which isplanned to have broad application in both blasting and rock mechanics. The purpose of this paper is to outllne the background that has led to the development of ROCSCAN, describe its objectives and to present a progress report on the work to date. Some of the potential applications of ROCSCAN will also be reviewed."

Jan 1, 1989

By J K. Claflin, S R. La Brooy

A case study from a current Ausenco project is presented to demonstrate the importance of maintaining high carbon activity to illustrate the driving force for plant improvements such as a carbon regeneration kiln upgrade.This paper revisits the factors that influence carbon activity for gold loading, with emphasis on deactivation by organic solution components such as flotation reagents.Kiln process design requirements for effective thermal regeneration are reviewed including the interaction of parameters such as temperature, kiln atmosphere and residence time.The different types of kilns that have been used for carbon reactivation are described. A check list is provided of what to look for when purchasing a carbon reactivation system for dealing with severely fouled carbon. This covers the ancillary equipment as well as the kiln itself.While the effectiveness of the carbon reactivation kiln is vital to maintenance of high carbon activity it needs to be remembered that this is only the end of pipe solution. It is also important to ensure that reagents such as frothers and flotation collectors are appropriately chosen to maximise recovery and at the same time minimise carbon deactivation.CITATION:La Brooy, S R and Claflin, J K, 2013. Carbon management in a high gold price environment, in Proceedings MetPlant 2013 , pp 455-467 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Xintan Chang

MFIRE is a computer simulation program that performs normal ventilation network planning calculations and dynamic transient-state simulation of ventilation networks under a variety of conditions. The program is useful for the analysis of ventilation networks under the influence of natural ventilation, fans, fires, or any combination of these. MFIRE simulates a mine's ventilation system and its response to altered ventilation parameters such as the development of new mine workings or changes in ventilation control structures, external influences (varying outside temperatures), and internal influences (fires). Extensive output enables detailed, quantitative analysis of the effects that the alteration will cause to the ventilation system. The program was developed at Michigan Technological University (MTU), Houghton, MI, with support from the Bureau of Mines. A personal computer (PC) version of the program was completed under contract for the Bureau by MTU. The purpose of this report is to document the installation and use of the PC version of the program MFIRE.

Jan 1, 1990

The production of sulphuric acid at Port Pirie by the contact process began in March 1924 with the commissioning of the Electrolytic Zinc Co.'s roasting and acid plant. This plant, operated by B.H.A.S. Pty. Ltd. on behalf of the E.Z. Co., continued to produce sulphuric acid from the gases evolved when roasting Broken Hill zinc concentrate in mechanically rabbled furnaces until September 1954, when the plant was closed down.In this peri9d of approximately 30 years some 600,000 mono tons of 98·5 per cent sulphuric acid was produced, most of which was used for fertilizer production at Wallaroo and Port Adelaide. During World War II 14,400 mono tons of the above was produced in the form of 20 per cent Oleum and railed to the Salisbury Munitions Factory for use in the production of nitro-glycerine, gun-cotton and T.N.T.In the early post-war period various ways of converting at least some of the sulphur in the gases' discharged to atmosphere from the lead sintering plant were considered until, in 1949, it was decided to erect a modern contact acid plant. Much work remained to be done on the roasting plant to produce a gas of suitable grade for the contact process and also on the design of a purification section suitable for the treatment of D.L. gases.The acid section itself, however, was largely of conventional design and it was therefore decided that this would be erected first. To it was then attached a sulphur-burning section to allow it to operate as a "hot gas" brimstone acid plant until the roasting and gas purification plants had been designed and erected. In this way the urgent need for sulphuric acid in the fertilizer industry would be relieved, to some extent at least, as soon as, possible.

Jan 1, 1956

By D. Kolymbas

A simple formula is introduced which allows the evaluation of dynamic pile tests. The following case is considered: The pile top is dynamically loaded by an impact. The velocity v of the pile top is recorded over the time. Let v1 and v2 be the first and the second maximum of this curve. Then, the pile bearing capacity (resulting from ideally plastic resistance at the pile wall and at the tip) can be set approximately equal to Z(v1- ½ v2), where Z is the impedance of the pile cross section. Due to the assumption of ideal plastic resistances, radiation damping needs not be taken into account. Material damping may be important in rate sensitive soils (such as clay, even if it is highly overconsolidated). A simple correction procedure for material damping is proposed.

Jan 1, 1989

By D. Harrington

The greatly extended use of the underground trolley-locomotive system for hauling coal without doubt was one of the most important factors in the rapid progress of coal mining and the increased production of coal in American coal mines during the period 1910-20. Much of the superior efficiency of production of our underground coal and metal lines should also be credited to the trolley locomotive system. The trend to mechanization of mines during the past 15 years, mere particularly the past 5 years, with higher production per man employed and greatly accelerated advancement of working places, has required increased use of trolley locomotives, necessitating larger equipment, higher speeds, and more 'frequent turn over of pit cars. This is re¬flected in increased size of locomotives and the use of larger mine ears (some with a capacity up to or over 10 tons); moreover, heavier rails and larger-size trolley wires have boon or ought to have boon installed. Trolley-locomotive haulage has proved to be rapid; economical, efficient, and productive; nevertheless; in spite of these advantages, so-many hazardous features and, unsafe conditions are involved and the price paid in life and property is so high as to justify the statement that the system should be scrapped if it cannot be operated under reasonably safe conditions. Since bare trolloy wires were introduced into underground mines, they have boon responsible for the death of hundreds of diners, property damage totaling millions of dollars, an indeterminate loss of tonnage through the abandonment of mines or parts of mines, and loss of time after disasters caused by fires or explosions originated by the trolley haulage system.

Jan 1, 1945

By Unknown

Blast Site Security Involves: * Clearing the area * Controlling Access * Warning Signals

Jan 1, 2003

By G. C. Price

This study traces the development of the bucket-wheel excavator, points out the differences in the German- and American-type wheels, and gives the major design criteria and the advantages and disadvantages of bucket-wheel operations. A computer program, written in FORTRAN IV for use with an IBM 360 computer, simulates the operation of the digging components of a bucket-wheel excavator. By supplying certain mining dimensions, soil characteristics, and machine design specifications, this program will print out a time study of the various components of an operation, power calculations for the operation, and production data. This program, when combined with a truck, belt, or rail program, should be helpful in planning a complete mining system In material suitable for a bucket-wheel excavator operation.

Jan 1, 1973

By M Stevens, M P. Simpson, J L. Mauk

The Karangahake deposit was the second largest producer of gold-silver bullion in the Hauraki Goldfield, New Zealand. New mapping of a 2 + 3 km (6 km2) area demonstrates that hydrothermal alteration surrounds productive veins. Wallrocks proximal to veins are intensely altered and alteration decreases toward the margin of the system.   At Karangahake, distinct zonation of adularia, calcite, epidote, illite and illite-smectite surrounds gold-bearing lodes with unaltered rocks containing magnetite and plagioclase occurring on the margins. Adularia, illite, illite-smectite, and calcite zonation defines hydrothermal alteration extending 2 km to the east of productive lodes. Epidote and adularia zonation occurs proximal to veins. The adularia zone compares well to potassium/thorium studies conducted in the area. Illite zonation is well developed to the east of the veins grading into interstratified illite-smectite containing 5 to 40 per cent smectite 1.5 km from the Maria Lode. Calcite is restricted to the east of the study area occurring in 18 per cent off surface samples. Less altered rocks containing plagioclase and magnetite occur distal to veins. The magnetite occurrence compares well to aeromagnetic studies conducted in the area.   Adularia and coexisting adularia and albite indicate the host rocks were highly permeable. Epidote, illite, illite-smectite and previous fluid inclusion evidence implies temperatures graded from >240¦C in the core of the system to approximately 150¦C on the periphery. The alteration association of quartz, adularia, calcite, pyrite, chlorite, illite and illite-smectite reflects a near-neutral to weakly alkaline water. Calcite occurrence and the absence of zeolite imply the fluid contained significant dissolved CO2.

Jan 1, 2005

By Willie M. NeSmith

Conventional augered, cast-in-place (ACIP) piles were introduced into the New York City area as a result of the damage to existing structures caused by pile driving operations. ACIP piles are often specified where deep foundations are to be installed adjacent to transit facilities, sensitive underground utilities or in close proximity to existing structures. However, loss-of-ground issues associated with the installation of ACIP piles have prevented the wide-scale use of these systems. Beginning in 2002, Berkel & Company Contractors, Inc. began using its augered, cast-in-place displacement (ACIPD) system in the New York City area. Like conventional ACIP piles, this system produces almost no vibration. Also, as almost no material is brought to the surface, there is no opportunity for loss of ground. This paper presents a description of Berkel's displacement pile system and a brief discussion of six projects in the New York City area that have been executed with this system over the past two years.

Jan 1, 2004

After the Loma Prieta Earthquake, which caused major damage to viaducts in the Bay Area, the California Department of Transportation set up a test programme for foundation piles. Funderingstechnieken Verstraeten B.V., beter known as Fundex, was approached, since one of the piling systems of Fundex, named Tubex, is extremely suitable in areas sensitive to earthquakes and we were very much interested to prove the capabilities of this piling system. Equipment For the installation of Tubex and Tubex grout-injection piles special piling equipment is required. Since our company is not only a contractor, but also a designer and manufacturer of piling equipment, all special equipment for our range of foundation techniques is designed and built by our own piling equipment department. For the installation of both Tubex piles and Tubex grout-injection piles for the Caltrans test programme, the following pieces of equipment were selected: a) Fundex F12 piling rig b) Drill table c) Hydraulic powerpack d) Grout mixing unit and high pressure pump

Jan 1, 1993