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By A. B. Young

THERE were produced in this country in 1923 probably in the neighborhood of 12,000 or 13,000 tons of refined and crude arsenic, by far the greater portion coming as a by product of smelting operations. Early this year copper smelters were producing arsenic at the rate of about 425 tons per month and lead smelters at the rate of 7;0 tons per month. During the entire eighteen years prior to 1919, there were produced in the United States only 47,000 tons of arsenic, which amounts to only 25 per cent. of the present output. The great increased demand has come about through the augmented use of arsenates as insecticides and arsenates as weed killers. In an extract from "Mineral Resources of the United States" on "Arsenic in 1922," Messrs. Heikes and Loughlin say, "The minimum possible demand for arsenic in 1923 was estimated at the end of 1922 to be about 13,000 tons, including 2000 tons for plate glass manufacturers, 3000 tons for lead arsenate, 3500 tons for calcium arsenate, 1500 tons for weed killers, 1200 tons for Paris green, 1000 tons for sheep dips and 750 tons for proprietary mixtures. More recent information, however, indicates twice as great a demand for calcium arsenate." The latter has found great use in the last three or four years as a weapon to combat the boll weevil pest of the southern cotton belt. ~t the present writing refined white arsenic is being quoted on the New York market at from 13)d c. to 1455 c. per Ib., while the average price during the eighteen-year period just mentioned was 4.8 c.

Jan 1, 1924

By Ming-Feng Ye, Jun Wang, Guang-liang Wu

In order to reduce the Al2O3 inclusions in 50Cr5MoV roller steel produced by EBT-LF-VD-VC process in a steelmaking plant, the LF refining slag was optimized and the influence of optimized slags with different w(CaO)/w(Al2O3) ratios on reducing inclusions were investigated in the laboratory. The results showed that, when w(CaO) = 50–55%, w(Al2O3) = 25–30% and w(CaO)/w(Al2O3) = 1.5–2.0, this optimized slag can not only reduce massive Al2O3 come from aluminium deoxidation, but also change the remain into plastic CaO-MgO-Al2O3 spherical compound inclusions with 1–5 lm diameter, the harm on the performance of the steel was minimized.

Mar 1, 2018

By J. Seiter

Mining has always been among the most hazardous of occupations, and with the increasing demand for coal and minerals, safety in mines assumes even greater importance. Worldwide, underground miners are being exposed to noise and respirable dust hazards associated with roof bolt drilling. These hazards are now being understood to cause irreparable damage to the health of miners. The objective of this research was to discover if a Polycrystalline Diamond Cutter (PDC) drill bit generates less respirable dust and hazardous noise than a competing Tungsten Carbide (WC) bit, in dry vacuum drilling. In order to control the drill parameters the drilling tests have been conducted in a laboratory setting. The results were met by determining the quantities of dust and noise generated using each drill bit and analyzing those levels by using monitoring devices and software to collect the data. This paper includes information on experiment setup, equipment used, drilling parameters, and data collected. The test results suggest that there are noticeable trends that the PDC bits produce less dust than WC bits but more testing is needed to substantiate these trends.

Feb 23, 2014

By M. Hamamoto, S. Tanaka, K. Noda

"Tamano Smelter or Hibi Kyodo Smelting Co. Ltd. is operating with the Tamano Type Flash Smelting Furnace method which is a flash smelting furnace without slag cleaning furnace but which can discharge a slag equivalent to that from the slag cleaning furnace and with the development or coke combustion technology which is the basis of this world's only one type flash smelting furnace process, the smelter exhibits a low operation cost under high productivity operation. Utilizing this experience and improving it we have developed and put to practice an operation guide system using a general purpose computer in order to further establish s stable operation. In this paper these improvements are described. Background of System DevelopmentWith the recent rapid progress of general purpose computers and improvements in their performance an environment for the use or computer in process simulation at low cost and simple operation has been established. If an accurate operation simulation can be done with the Tamano Type Flash Smelting Furnace the merits would be very great and thus we started development of the system. The official name of this system is Computer guide system for Coke Combustion in the T-FSF and taking the initial letters we call it CCCT. We aim to achieve operation with stable mane grade, temperature and slag loss in the furnace by maintaining the most suitable combustion conditions of concentrate and coke in the flash furnace with the assistance of CCCT to the flash smelting furnace operators.Through several production expansion projects clone in the past by oxygen enrichment the copper concentrate treatment quantity and matte grade have increased step by step as shown in Figure I. Following this increase the difference between the operation calculation results al the initial stage of coke combustion and the actual behavior of furnace (matte grade. temperature in the furnace. etc.) gradually became bigger. Further operation procedures taken by different operators against the same phenomenon were sometimes different depending on each individual, which from time to time caused the operation to become unstable. Prior to the development of the system we checked out thoroughly the weak points of operation calculation procedures which were in practice until that time. The results were analyzed and study was carried out to establish a most suitahle operation calculation procedure and finally we reached this system"

Jan 1, 2000

A Discussion of the papers of James Gayley, on "The Application of Dry-Air Blast to the Manufacture of Iron" (see Trans., XXXV., 746, 1022, also pp. 315 and 745 of the present volume, and of J. E. Johnson, Jr., on "The Physical Action of the Blast-Furnace," p. 454. Chas. B. Dudley, Altoona, Pa.:—I am not a blast-furnace man, and this always puts me at a disadvantage because I cannot go into the details of the making of iron and steel. I have not the experience, and have to take the statements of other people, so what I say regarding the subject of this paper is not in the sense of an expert. When I first heard of Mr. Gayley's experiments, I said to myself, a I fear they will result in failure, since, apparently, Mr. Gayley has forgotten one chemical fact, namely, that carbon does not combine with oxygen in the absence of mater-vapor." This fact which was so astonishing when it was first brought out some years ago, and which those who are interested may find in the Journal of the Chemical Society of London, for 1885, page 349, and 1894, page 611, led me to think that the drying of the air would be a mistake. The general subject of the influence of water-vapor on chemical action is a large one; but the special point in which we are, for the moment, interested, namely, the influence of water-vapor on the combustion of carbon, was especially treated by Mr. H. B. Baker, in the papers referred to. Apparently, however, as the result of Mr. Gayley's experiments, we are to learn that the amount of moisture still left in the desiccated air is sufficient to secure perfectly satisfactory combustion. In thinking over Mr. Gayley's paper, it occurred to me that there were two alternatives, either of which might be chosen, namely, we might dry the air as Mr. Gayley does, or possibly we might, in a very much easier way, simply saturate the air at a constant temperature, and thus get uniform working and

Jan 1, 1906

By S. Sundararajan, Z. Lin

ABSTRACT Fierce market competition and demand have made it imperative for mining companies to achieve higher productivity and operational efficiency. The selection of the best mining method and equipment combinations will enable companies to meet production and efficiency targets. Continuous mining is increasingly preferred by companies for its high efficiency and low unit costs. We developed simulation models for two continuous mining systems: the continuous surface miner (CSM) system and the at-face slurrying (AFS) system. Considering two different case studies, the paper discusses application of developed models to determine the optimal number of trucks and equipment capacities for the two systems.

Jan 1, 2013

By J. F. Myers

AT the Regional meeting in Columbus, Ohio, in September 1949, the authors presented a progress report of the first year's operation with a Hardinge tricone mill in closed circuit with a Dorr hydroscillator. The present report covers our findings on this grinding circuit to January, 1950. In order to clarify our position, the authors wish to state that no invention or discovery is claimed. The Tennessee grinding circuit is simply an engineered arrangement of known equipment arranged to incorporate all of the recognized efficiency factors of comminution as they are known today. As we concluded our first report, it was not clear how effective the Tennessee mode of operation would be on harder ores. The only information we had at that time was that the Bond grindability test at 48-mesh gave 6.04 g of undersize per revolution. A later test on the same sample at 100-mesh reduced this to 2.04 g, which is definitely in the harder ore class, and which makes the reported 8.80 kw-hr per ton of -200-mesh produced a very creditable figure.

Jan 1, 1950

By John Goodell

CIVIL engineers seem to number in their ranks more advocates of licensing than are found among the practitioners of other branches of the pro-fession. Licensing was not originated by civil engineers but it was forced upon them in two ways. In the first place, the civil engineering profession has hangers-on like every other profession. The first legislative result of their imperfect accomplishments with which I am familiar occurred in the far West. It was found that early irrigation works were so badly planned in some cases that not only were water rights made very uncertain but considerable sums were invested in structures and ditches which proved inadequate and occasionally complete failures. Water was too valuable to be wasted in that way and money too hard to obtain. In those sections, therefore, laws were passed many years ago which made it obligatory for the design of irrigation works and other structures utilizing water to be made by engineers who had satisfied a board of examiners that they possessed the technical qualifications to plan such works properly. The basic thought on which such laws rest is the same as that on which laws governing the licensing of boiler operators rest, namely, the safety and welfare of the public. While boiler explosions still occur and irrigation works are built which are not wholly satis-factory, these laws have helped the, public, it is gener-ally agreed.

Jan 4, 1922

By Daniel Richards, Dr Rob Farnfield, Dr Geoff Adderley

The 8-millisecond rule has been in use for many years as a basic technique to help minimize vibration levels from surface blasting operations. The rule was based on work carried out in the 1960’s by the USBM by recording the vibration levels from a series of test blasts in a quarry over a range of distances. This work included the firing of a series of single hole blasts and a number of single row production blasts using a variety of inter-hole delay times. The delay times employed were limited by the technology available at that time to instantaneous, 9, 17 and 34 milliseconds. There have been several papers in recent years suggesting that the use of the 8-millisecond rule is no longer required, when using electronic detonators, due to their enhanced accuracy and greater initiation pattern design flexibility. This paper examines this proposition by revisiting the original work and employing the linear superposition technique to reprocess some of the original recordings. Similar techniques are then applied to a large database of single hole vibration recordings for a range of rock types, distances, and number of decks, with calculated reinforcements compared to the minimum separations in typical patterns. The results suggest that there is some validity to the 8-millisecond rule when applied to electronic detonators but not in the way it is traditionally applied. Simple guidance is suggested for those designing blasts with electronic detonators to minimize vibration levels even if the benefits of linear superposition trials are not available.

Jan 21, 2025

By W. T. Irvine

"The H.B. Mine, a zinc-lead operation of the Consolidated Mining and Smelting Company of Canada Limited (Cominco), is in south central British Columbia, on Sheep Creek, a west-flowing branch of the Salmon River. It is 3 miles by road from B.C. highway No. 6, 30 miles south of Nelson, B.C., with an excellent highway connection to the smelter city of Trail, 35 miles from the mine. The nearest permanent settlement is the village of Salmo, 7 miles distant by road. The mine is situated along a belt containing other important zinc-lead deposits, including those of the Canadian Exploration Company, 3 miles to the south, and the Reeves MacDonald mine, 9 miles distant again to the southwest.Deeply oxidized outcrops were located in 1907 on the north side of Sheep Creek valley by two prospectors named Horton and Benson. The property was given the name H.B., after the two discoverers, and there commenced a long and intermittent series of mining operations designed mainly to develop and extract oxidized lead-zinc ore. In 1925 a determined attempt was made by a British syndicate to develop a large tonnage of sulphide ore, but this ended in failure after some 3,000 feet of lateral development had been done. In 1927 Cominco acquired the mine, but it lay idle until 1946 when a geological study was followed by a program of surface drilling which encountered extensive sulphide mineralization. An underground development program revealed more details of the deposit, and sufficient ore was found to warrant construction of a 1,000-ton mill. Mine preparation and mill construction were completed by early 1953, but production was deferred due to low metal prices. The mine was finally brought into production early in 1955."

Jan 1, 1949

By L. E. Young

MUCH has been said and written on this subject and probably little new can be said. However, the point of view of the operating company changes from time to time, and more stress may be laid upon a subject today than was done some years ago, and it is with this changing point of view that the following observations are presented: The writer wishes to limit the discussion to views of a company mining bituminous coal, particularly to what the production department expects of the college grad¬uate. In an editorial in MINING AND METALLURGY for February, 1929, entitled "Is. Mining Engineering Passing?" it is stated that: It is not by accident that mining engineering courses have been general rather than special and form even today the only general engineering courses widely offered and followed by engineering students.'* * * even in this age of specialization, the mining engineers remain a body characterized particularly by broad knowledge.

Jan 1, 1929

By R. B. Corbett

"INTRODUCTION Aluminum and manganese bronzes as a group, may be separated readily from other copper-base alloys by experienced sorters. However, separation of aluminum bronze from manganese bronze is generally a matter of guesswork, so that accurate separation presents a difficult salvage problem.Attempts at separation by the thermoelectric tester. 3/ which had proved successful in solving other sorting problems, showed in this instance that the desired separation was uncertain because of the wide range of composition allowable in each kind of bronze. If only one composition of each kind of bronze were used in industry, separation by the thermoelectric method probably would be simple. However; the variability in composition observed in commercial alloys is so great that the thermoelectric power of the one type frequently overlaps the range of values found for the other. As a result, specimens frequently are classified in the' wrong group.Separation of the two types of bronzes on the basis of measurements of magnetic properties on filings from the various samples also proved unsuccessful because the test results overlapped to such an extent that no clear-cut division could be obtained.Electrode potential measurements were made also on the aluminum and manganese bronzes in the hope of distinguishing between them. A drop of saturated potassium chloride solution was placed on the fresh surface of the metal and the tip of a calomel electrode introduced therein. The voltage generated was measured by connecting the electrode and the bronze part to a research-type potentiometer. Although the voltages generated by the manganese bronze parts were greater than those generated by the aluminum parts, the difference in the closest two sets of readings was not sufficient to warrant a good separation. When a concentrated potassium alum solution was used instead of the potassium chloride solution, a wider divergence of voltage was produced by the various bronzes, but unfortunately readings overlapped in several instances."

Nov 1, 1944

By A Reid, A W. Musk, O Jones

In this paper, the authors attempt to bridge the gap that currently exists between the duty-of-care responsibilities of underground mining industry personnel, and the multifaceted health challenges facing mineworkers in Western Australia’s metal mines where diesel-powered mobile equipment predominate. In addressing this issue, the complexities of the nature and extent of the challenges are discussed along with the current inadequacy of existing regulatory metrics. Support is given to the need for well-organised in-mine baseline studies to clearly define the distribution and aging characteristics of the toxic and carcinogenic pollutants within the mine ventilation system, with special emphasis given to exploring the validity of biomonitoring systems. The paper concludes with the proposal that a template risk assessment data sheet be prepared for the industry to provide mining personnel with a sound basic knowledge of the health risks involved and the control measures and precautions available for minimising and/or eliminating the hazard.CITATION:Jones, O, Musk, A W, Reid, A and Davis, C, 2017. Risk assessment tool for mines using diesel-powered mobile equipment, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 151–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By A. J. Antony Chettupuzha

During a construction project, it is important to ensure that accurate and pertinent knowledge is delivered on time to appropriate personnel. The criticality of documents exchanged or referred to by various parties, evolves over the course of the project lifecycle. Determining the criticality of documents at different stages of the project can aid companies with managing the flow of information in an organized manner, while providing for the detection of potentially disruptive, erroneous material that could result in delays and costs. Therefore, it is crucial to determine documents which have the potential to disrupt a process (by virtue of being incorrect versions etc.) so that they may be isolated or prevented from entering or interfering with the active flow of information in a project, while also ensuring standard revisions of documents are recognized and accessed accordingly. Electronic Product and Process Management [EPPM] systems provide the capability to establish and map information flow between different parties in a construction project. Analyzing an EPPM system may yield information about the criticality of certain documents within an activity, as well as isolate characteristics peculiar to documents which can assist in risk mitigation. We propose methodology that identifies such critical documents.

Aug 1, 2013

By H. R. Taylor

The history and development of this property is more or less familiar to nearly everyone connected with the mining industry, so that only a brief outline of the more important facts will be given in this article. In 1916, a small pilot mill was constructed by the British Columbia Copper Company at Copper Mountain, and during 1916 and 1917 test work was conducted to determine the possibility of concentrating the ore and also to work out a suitable flow-sheet. In the spring of 1917, the location of a mill site at Allen by, which is about 8,% miles from Copper Mountain, and near the Similkameen river, was decided on, and the designing of a 2,000-ton plant was then worked out by Bradley, Bruff and Labarthe. Early in 1918, the actual construction of the concentrator began, and, after considerable labour difficulties, it was completed in 1920. During this period of construction, the West Kootenay Power Company ran a 60,000-volt power line over from Greenwood, a distance of 102 miles, and also built a sub-station at Allenby to take care of the mine and mill. The concentrator was started up on October 20th, 1920, and ran until December 11th, 1920, a total of 18,354 tons of ore being milled. The results of this short period of operation were encouraging, but, due to tlie prevailing low price of copper and high wages, it was necessary to shut down until a more favourable time. During the latter half of 1923, some work was done on remodelling the mill. This work continued until January 8th, 1924, when it was suspended.

Jan 1, 1929

By D. Whittles, S. Kingman, S. Bradshaw, N. Miles

The influence of microwave energy at high electric field strength on ore strength has been investigated. Two ores of varying mineralogy were treated in both multimode and single mode microwave cavities. After treatment, any change in strength relative to untreated ore was established. It was shown that in the multimode cavity reduction in strength was related to the applied power level. Results of tests carried out in the single mode cavities showed that, for both ores, reductions in ore strength > 50% could be achieved in very short periods (<1 second). Thermal stress analysis showed that the mechanism of microwave induced failure was the development of tangential stresses at the grain boundaries. It was concluded that operation at 915 MHz with high power and short residence times gives feasible scale-up possibilities.

Jan 1, 2003

By Paul B. Warrington

This paper presents a discussion of the factors affecting copper scrap markets, including such items as price levels, freight. grades of material, sources and packaging. Reference will also be made to the effective life and turn-around of the copper content of some products. Introduction IN TERMS OF SIZE, copper scrap is second only to ferrous scrap in tonnage recycled. However, in total value, it is second to none. For example, world scrap recovery during the preceding 4 years averaged just under 2,300,000 metric tons per annum, and at an average price of 70 ¢ a pound, this works out at a turnover of about $3.5 billion, which indicates that the copper scrap industry, or recycling as it is now becoming known , is a substantial one.

Jan 1, 1977

By Jie E. Zhou, Yu U. Wang

"Development of crystallographic texture in polycrystals during templated grain growth process is studied by phase field modeling and computer simulation. To characterize the grain texture development, X-ray diffraction peak intensities are computed for the evolving grain structures as simulated by the phase field model, based on which Lotgering factor is further calculated as a quantitative measurement of uniaxial texturing. While the phase field modeling allows direct comparison between simulated grain structures and experimental microscopy observations, the computational diffraction allows convenient correlation between computer simulation and experimental X-ray diffraction characterization. The latter feature is especially desirable, since microscopy experiments normally require more efforts than X-ray diffraction, and diffraction is usually the preferred choice for material characterization.IntroductionThe properties of individual grains in polycrystals are generally anisotropic, while untextured polycrystalline materials with random grain orientations exhibit isotropic macroscopic properties that are independent of directions. In order to achieve anisotropic response in polycrystals, crystallographic texturing of grains is required [1]. Texture refers to the collective distribution of grain orientations towards preferred orientation in a polycrystal. To develop texture, special processing routes are needed, such as templated grain growth (TGG) for uniaxial texture [2]. TGG has been shown to provide uniaxial texture in wide variety of materials. For example, [001]-textured ferroelectric polycrystalline ceramics have been fabricated by TGG process, which exhibit enhanced piezoelectric properties [3]. Such highly textured polycrystalline materials offer better cost-performance ratio than single crystals. Thus, texture development in polycrystals is of technological importance for material applications.In this computational work, grain texture development in polycrystals during TGG process is studied. Grain structure evolution is simulated by phase field model, X-ray diffraction peak intensities for the evolving grain structures are computed, and Lotgering factor is calculated to quantitatively measure the development of uniaxial texturing. The phase field modeling allows direct comparison between simulated grain structures and experimental microscopy observations using imaging techniques such as scanning electron microscopy or optical microscopy. The computational diffraction allows convenient correlation between computer simulation and experimental X-ray diffraction characterization. The latter feature is especially desirable, because microscopy experiments normally require more efforts than X-ray diffraction, thus diffraction is usually the preferred choice for material characterization."

Jan 1, 2014

By P. K. Jain

A spiral concentrator is a density separation device used for the beneficiation of coal and various minerals such as iron ore, chromite ore, gold, beach sand minerals etc. The flow pattern developed in the equipment is complex and unique, yet the operation is very simple, with low capital and operating expenditure. Spirals are applied for beneficiation of material in the size range finer than 2 mm and are capable of recovering heavy minerals as fine as .01 mm. The understanding of the unique flow pattern has kept researchers engaged over the last few decades and attempts are being made to explain such flow patterns so that they can be controlled and modified to improve the operating efficiency, Ep (Ecart Probable Error, also known as probable error in separation) and acceptability of spiral concentrators for processing of fines and slimes - currently being discarded and dumped in the tailing ponds. An attempt has been made in this paper to explain the generation of complex flow patterns with application to classical solid mechanics in the fluid and slurry system. The same has been used to explain the selective separation of particles in different zones in a cross-section on the spiral trough. The paper also discusses the application of a force balance model to explain the generation of secondary circulation. Due to the presence of laminar and turbulent flow regimes in the spiral concentrator, varieties of equations have been proposed in the literature, consisting of different equations for different zones. An attempt has been made to present a unified flow equation for calculation of flow velocity at different positions on the spiral trough. Keywords: Secondary circulation, spiral concentrator, density separation, fine particle processing

Jan 1, 2020

By Hongpu Kang

The fully mechanized top coal caving mining method has been the main mining approach for thick coal seams with high output and efficiency in Chinese coal mines. The gateroads for the top coal caving mining faces should be driven along the floor of the thick coal seam with a part of the seam as roof. The support of the gateroads is commonly difficult because of the low strength and broken structures of the coal seams, and the increasingly large section of gateroads meeting the need of greater and greater face coal output. Based on the analyses on the geomechanics properties and production conditions of the top coal caving mining, the influences of the top coal caving mining parameters on the stability of gateroads, including mining thickness and face length, are studied. The deformation and damage features of the rock mass surrounding the gateroads with the top coal seam as roof are investigated, the interaction of the support with the surrounding rock mass, the support theory are studied. The bolting design method and criteria, bolting forms and parameters for the gateroads with the top coal as roof are put forward. The rock bolting components, including bolt bars, face plates, cable tendons, meshes, and steel straps, are introduced. Finally, the gateroad bolting effects are evaluated through a typical case study on the basis of field monitoring data, such as the displacement of surrounding rock mass and the forces along bolts and cables.

Aug 1, 2013