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A process was developed to produce electrolytic manganese dioxide, suitable for use in high quality dry cells, from Risdon anode mud. ImpurItIes present In the anode mud were removed prior to the electrolysis which was performed from a manganese sulphate bath using the following conditions.Temp. 95°CH2S04 50-55 g/l.Mn2+ 55-60 g/l.Anode c.d. 10·0 A/sq. ft.Operation under these conditions yielded current efficiency and power consumption figures of 95 per cent and 0·8 kWh/lb respectively. The product conformed to battery manufacturers' specifications as regards physical and chemical properties and performed satisfactorily in a battery testing programme.

Jan 1, 1968

By M. Berger

The ‘Metallurgical Operations’ Department of Grinaker-LTA Process Engineering (GLTA) currently undertakes then primary mining as well as the re-deposition of tailings forTicor South Africa (Ticor) at their Hillendale mine near Empangeni, KwaZulu-Natal, South Africa. The mining plant, which was designed by GLTA on a Build, Own, Operate and Transfer (BOOT) basis, is capable of mining 780 000 tons per month of ROM material which is then pumped to the Primary Wet Plant for treatment by Ticor. Hydraulic mining via high pressure water cannons and subsequent transfer of the heavy mineral slurry at an RD of between 1.35 and 1.48, has never before been undertaken successfully at this level of production on an in situ reserve. The presentation will take the form of a case study in which the unique site operating conditions will be detailed and discussed, as will the innovative process and engineering solutions employed by GLTA to overcome the engineering and production challenges encountered. In order to protect the intellectual property involved in this operation, this paper is fairly general in nature, and attempts merely to provide the reader with a broad perspective understanding of the operation, and some of the difficulties encountered during the early stages of production.

Jan 1, 2003

By A. C. Richardson

The mine of the Porter Coal Co. is located at the town of Porter in the northwestern part of Jefferson, County, Ala., about 20 miles west of Birmingham. The operations in this mine are confined to the middle and bottom benches of the Mary Lee bed. The coal from the Porter mine is handpicked and washed before being placed on the market. The handpicked lump coal and the washed egg and nut, coal are sold chiefly as domestic and steam-raising fuel. The coal finer than 1 inch is washed in 2-compartment jigs and utilized in the manufacture of metallurgical coke. The coal company has found that, when coal ranging in size from 1 to 0 inch is washed in jigs, a considerable amount of high-ash material finer than 3/16 inch remains in the washed coal. This paper gives the results of an investigation which was conducted for the purpose of determining the washing characteristics of the through 316-inch raw coal and the extent to which the ash might be reduced by means of coal-washing tables. This investigation has been made in connection with an. extensive study of the coal-washing problems now being conducted by the United States Bureau of Mines and the University of Alabama, with the cooperation of the coal-mining companies of the State.

Jan 1, 1933

By Rob Farnfield, William Birch, Douglas A. Anderson

In the blasting industry, even to the most safety conscious shotfirer, misfires are a constant source of concern. In the United Kingdom, there are two types of misfire, as classified by the Health & Safety Executive. Type A occurs when testing a shot before firing reveals broken continuity that cannot be rectified. However, due to the fact that a majority of quarries use non-electric initiation [i.e. shock tube] that cannot be tested, this type of misfire is very unusual.

Jan 1, 2016

By Cade Mweemba, Alex Mwanza, Jackson Sikamo

"The Zambian Copper mining industry as we know it today has its genesis from early in the 20th century in the 1920s. Consistent private sector-driven investment in the industry over a period of over 50 years in exploration, mine development and operation, development of minerals processing facilities, building of infrastructure for pyrometallurgical and hydrometallurgical processing, with attendant support facilities, including building of whole new towns, resulted in copper production going from zero to a peak of 769 000 tons of copper in 1969. At the same time, the industry created jobs to the extent that in 1972 the industry had over 62 000 direct jobs. The industry was nationalized in 1973 and remained in government hands for just over 24 years. During this period, the industry experienced a serious decline in production levels, reaching the lowest level at the dawn of the 21st century in the year 2000 when production was 250 000 tons. In terms of jobs, an average of just under 2000 jobs were lost every year in the 24-year period, reaching just over 22 000 direct jobs in 2000. Following the return of Zambian politics to pluralism and liberalized economic policies, the government decided to privatize the mining industry. The process started in 1996 and by the year 2000 all the mining assets had been privatized. The new investors embarked on serious investment to upgrade the assets and to develop greenfield mining projects. Fourteen years later and investments of over USD 12 billion, the industry production levels increased year- on-year to reach a peak of 763 000 tons in 2013 with direct jobs reaching 90 000. This paper discusses the impact of the mining industry in Zambia on the economy in areas such as employment, support to other industries, direct contribution to the national gross domestic product (GDP), foreign exchange earnings and social amenities. The paper also focuses on the performance of the mines during these periods vis-à-vis mineral availability, mineral grades and complexity, new technologies and human capital. This is looked at particularly in the light of current challenges the industry is facing and makes suggestions on how the industry can be nurtured to continue being a major driver for the Zambian economy and a major player in the international copper mining business."

Jan 1, 2015

By A. Çelik

Wheel loaders are widely used in many sectors due to their mobility, operational flexibility, and low costs. The literature is mainly focused on improving the hydraulic, mechanical, and electronic subsystems of these machines in terms of efficiency or developing strategies for controlling these systems. In this study, the effects of the loader operator and different working conditions on the loading performance were investigated. The study was carried out at the Can Lignite Enterprise (CLI), which is a major coal producer in Turkey. In the study, which lasted approximately four months, a total of 808 measurements were performed to investigate seven different scenarios. The effect of a single parameter on loading performance was investigated in the first six scenarios. The results showed that the biggest impact on loading performance was caused by the operator's experience with 63.4%. On the other hand, the worst and most ideal working conditions determined from the first six scenarios were tested in the seventh scenario. It was tested as a script. The test results showed that the loading performance was 285.5% more effective under the most ideal operating conditions compared to the worst operating conditions. In addition, in the study, the loading performances of five loaders with four different capacities were examined in terms of energy efficiency and it was determined that the Kawasaki 115 work machine, which has a higher model and lower engine operating hours, was more advantageous. In the study, various suggestions were developed in parallel with the research results. The most prominent and easiest to implement of these suggestions is related to the selection of the loader operator.

Nov 27, 2024

By Alfonso Rizo-Patrón Remy

El objetivo del siguiente trabajo es señalar un método que permita la recuperación económica de metales preciosos como el oro, plata y otros metales básicos (tales como plomo y cobre) de sus respectivas menas naturales y de los concentrados o relaves que los contengan. Para ello, se utlizará dos formas de aplicación: La primera se da en el tratamiento por cianuración de las menas, donde el carbón mineral es el medio precipitante de los metales disueltos. Mientras que la segunda ocurre cuando el carbón ha sido separado de las pulpas cianuradas, conviertiéndose en un agente reductor de los metales de fundición. De forma tal que se logra una recuperación integral de los metales preciosos y básicos en las barras de fundición.

Jun 20, 1954

By Kazuo Magata, Hirohiko Fujita, Masazumi Tashiro, Yoshiaki Sato, Yoshio Shinoda

The Shinkansen of the Japanese National Railways (JNR) presently in operation between Tokyo and Hakata, approximately 1,000 km, was constructed at three stages: between Tokyo and Shin-Osaka opening in 1964, Shin-Osaka and Okayama in 1972 and Okayama and Hakata in 1975. Works on the extension of 400 km from Okayama to Hakata were launched in March 1970. As construction of the undersea Shin-Kanmon Tunnel on the extension was the toughest task, requiring many, many months, the work was undertaken earlier than any other works on the extension. It was brought to its completion in June 1974 at the cost of about 22, 000 million yen. The Shin-Kanmon Tunnel is the third undersea tunnel constructed to connect the main island of Honshu and Kyushu across the Kanmon Straits. (Table 1)

Jan 1, 1976

By Robert Hopler

As a part of the depression and rectification work on the Port Morris branch of the Harlem Division of the New York Central & Hudson River Railroad, a short tunnel is being driven under St. Mary’s Park. The park is near 149th St. and St. Ann’s Ave., in the Borough of the Bronx, New York City.

Jan 1, 2006

By SMF Hossaini

With the aim of a clearer understanding of the applicability of existing empirical equations for blast induced ground vibration, an investigation has been conducted on three mostly applied forms of such equations. The effect of explosive type on the applicability of these equations has been assessed by analysing 44 sets of data produced by using two types of explosives, namely ANFO and slurry explosive, in an open pit coal mine. The analysis of the data has revealed that the type of explosive affects the applicability of the criteria of the three equations. All three criteria have better correlation with the data of shots in which ANFO was used than the shots with slurry explosive. However, the applicability of one of the criteria is reduced, by far, only by replacing ANFO with slurry explosive for the same ground conditions. It was also found that one of the parameters of these criteria (i.e. “k”) is significantly sensitive to the type of explosive in all the three equations. The degree of influence to the values of “k” obtained by the variation of explosive from ANFO to slurry explosive in the three equations is 76.3%, 811% and 39%. This implies that “k” is not only dependant on ground conditions, as stated in most previous publications, but is also strongly a function of the type of explosive.

Jan 1, 2004

By Ruxton B. P, Rhodes J. M

Two Rb-Sr ages are discernible in data concerning the leucocratic granite which is the youngest pre-sedimentation phase of the crystalline basement complex at Rum Jungle, Northern Territory, Australia. Whole-rockdata suggest that intrusion of this unit took place at about 2400 my ago, with a probable initial ratio around o·707; whole rock-potassium feldspar tie-lines indicate redistribution of strontium at about 1800 my ago. The former age correlates with other measurements on rocks which form basement to the mantling Pine Creek Geosyncline; the latter correlates also with isotopic evidence for regional metamorphism and emplacement of some younger intrusive granites elsewhere within the geosyncline. A few K-Ar ages, from scattered localities, conform generally with the later event or events which appear to have some connection with the structural deformation clearly observable both in the complex and the surrounding metasediments. It is these younger events which appear to match the residual evidence for the earliest detectable concentration of uranium minerals in the Alligator Rivers district.

Jan 1, 1977

By Terence P. McNulty

Gold-bearing outcrops were discovered in 1862 by Union soldiers garrisoned at Needles, CA, near the northwest corner of the future State of Arizona. Sporadic mining began several years later, but engineered shaft sinking and mill construction were not adopted at Oatman and the neighboring camp of Goldroad until about 1900. Geological interpretations in 1915 enabled major production during the next decade. In the late-1930s, USSR&M built a new mine and mill in Gold Road and the District flourished until closure by Federal Order L-208 in October 1942. For about a decade, Oatman’s mines were among the largest gold producers in the American West.

Feb 1, 2024

By K. Saikiran, A. R. Nalla

Longwall management, regular shield maintenance, and evaluation of ground control problems can be performed using real-time shield monitoring program. Based on real-time shield pressure data, evaluation of intensity and interval of periodic weighting, estimation of time-dependent pressure increase and the effects of geologic anomalies can be obtained. In this study, full-face shield pressure data of over 457 m (1,500 feet) of face advancement is analyzed to evaluate shield response in the presence of surface lineaments, floor undulations, and multiple main roofs. Shield pressure increase due to web cutting is also correlated with setting pressure during periodic weighting and normal time. In addition, time-dependent pressure increase rate on Sundays and holidays is also correlated with time average pressure and the location of previous periodic weighting.

Jan 1, 2000

By David Hake, David Salisbury

The Drainage Services Department (DSD) of the Hong Kong SAR Government commissioned the design and construction of the West Kowloon Drainage Improvement, Stage 2, Phase 2, Kai Tak Transfer Scheme (KTTS) project in 2000 to relieve potential flooding in Mong Kok caused by the insufficient capacity of the existing storm water drainage system. The KTTS involves construction of a 1.5km,4.4m drainage tunnel and a 450m long box culvert, running from Waterloo Road near Hereford Road to the existing Kai Tak Nullah in San Po Kong. This paper describes the design and construction of; the bored tunnel through both hard rock and soft ground using a slurry Tunnel Boring Machine (TBM), six associated access shafts, a connection structure at Waterloo Road and the box culvert connecting the bored tunnel to the outfall at Kai Tak nullah. Details will be provided on the contractor’s alternative designs adopted during the contract including the use of fibre reinforced shotcrete as one-pass temporary and permanent support for three of the shafts and modifications to the Engineer’s design for the box culvert structure.

Jan 1, 2005

By E. P. Youngman

This paper presents one of a series of digests of foreign mining legislation and court decisions that is being prepared in advance of a general report relative, to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the mining laws of British Guiana has been prepared from the best available sources in Washington and is, released subject to amplification and correction, if necessary, by United States foreign-service officials. INTRODUCTION The sources of information available in the preparation of this paper are the following: 1. The Crown lands ordinance, No. 32 of 1903, September 26, 1903.

Jan 1, 1934

By J. Cayouette

In 1995, Louvicourt mine started one of the first paste backfill operations in Canada. From 500 000 t in 1995, the annual paste backfill tonnage produced reached 800 000 t in 1999. The maximum throughput of the surface plant (including binders) is 3500 tpd with a final density of 75% to 76% solids which gives a slump of 15 cm to 17 cm. Following the start-up of the paste backfill plant, the backfill strength performance levels were well below the pilot plant’s predictions. The introduction of ferrous slag, laboratory tests on various binder ratios with or without additives, and the desliming of the tailings enabled us to optimize the mix and operation costs. Primary and secondary stopes are filled respectively with a paste containing 4.5% and 2% binders in a mixture of 20% cement to 80% ferrous slag. In certain stopes, the binder ratio may vary from 2% to 7%, but always in a ratio of 80/20. Six years after start-up, or 4.5 Mt of paste backfill later, this paper discusses the present operation and the major changes that have occurred over the years to optimize both the operation and the paste fill quality.

Jan 1, 2003

By R. G. Knickerbocker, David Schlain, F. K. Shelton, J. H. Jacobs

"Many manganese ores contain from 0.1 to several percent cobalt. If such ores arc used for the production of ferromanganese, the cobalt is lost; on the other hand, if they are used for the production of electrolytic manganese, the cobalt can be recovered during the purification of the electrolyte.The production of cobalt in the United States is insignificant compared to the amount consumed, most of which is imported from the Belgian Congo. Cobalt-bearing manganese ores may therefore constitute an important reserve of cobalt in times of emergency. Moreover, the combined value of manganese and cobalt in some ores may be sufficient to warrant the recovery of both metals by the electrolytic manganese process, whereas the recovery of either manganese or cobalt alone might not be economically feasible.In view of the potential importance of manganese ores as a source of cobalt, a survey has boon made of the cobalt content of manganese ores. Most of the data have been obtained from analyses made in the Bureau of Mines, but valuable data have also been obtained from publications of the Geological Survey, various State publications, and other sources. Unfortunately, most published analyses of manganese ores do not include cobalt determinations; when such analyses were fairly detailed, but did not include cobalt, it was presumed that cobalt was not present in significant quantity.Information on the cobalt content of domestic manganese ores is given in table 1. Ores containing 0.1 percent or more cobalt are listed in table 2, and the districts in which such ores occur are shown in figure 1. Most of the known cobalt-bearing manganese ores occur in the southeastern part of the United States. A group of deposits in central Arizona and a few scattered deposits in other States also' contain cobalt."

Apr 1, 1946

By Tiezheng Li

Keywords: Laminate Composites; Mechanical Behavior; Damage Evolution The mechanical performance of Ti-6-4-Al3Ti metal-intermetallic laminate (MIL) composites synthesized by a reactive foil sintering technique was evaluated. Crack morphology of untested Ti-6-4-Al3Ti MIL composites has been characterized by optical microscopy. Mechanical tests were performed on Ti-Al3Ti metal-intermetallic laminate (MIL) composites and pure Al3Ti, and the principal mechanisms of damage initiation and accumulation were identified experimentally. The elastic properties and anisotropy of the laminates were calculated and successfully compared with Resonant Ultrasonic Spectroscopy (RUS) measurements. The effect of residual stress on the fracture toughness of the Ti-6-4-Al3Ti MIL composites was analyzed.

Jan 1, 2005

WHEN mining and treatment first started at Broken Hill only oxidised ores were available. These ores were rich in silver and lead-the silver mainly existing as chloride and the lead as carbonate.Treatment processes aimed mainly at the recovery of silver, lead being regarded as a by-product, and its recovery, except in so far as it affected silver recovery, was of minor importance.The first ore mined was carted to Terowie and thence railed to Melbourne, being smelted by the Intercolonial Smelting and Refining Co., of Spotswood.The first parcel (50 tons) returned £7442, or £148 16s. per ton to the Broken Hill Proprietary Company.The second parcel of 1053 tons, smelted at the Day Dream smelter, returned 132,142 oz. of silver, but no record is available as to its lead content.These results obtained from two parcels showed that by smelting the ore a handsome profit could be obtained, and Mr. La Monte was engaged to erect two 30-ton Nevada water jacket blast furnaces on Block 13. These furnaces were placed in charge of Mr. P...

Jan 1, 1928

By R Lewis

Drill hole magnetometric resistivity (DHMMR) is a relatively recent addition to the explorationistsÆ suite of techniques for finding further resources in the vicinity of a drill hole. The method relies on gathering of an applied current into zones which are less resistive than the country rocks and it was first applied to exploration programs looking for weakly conductive sulphides, such as, for example, carbonate-hosted zinc deposits. More recently, it has been applied to a wider range of deposit styles, including highly conductive nickel sulphides. It has been found that the technique is capable of not only detecting mineralisation not seen by conventional electromagnetic (EM) techniques, but it can detect at a greater distance. Also, whilst EM is superior at defining tabular-shaped conductors, DHMMR may be more effective at finding cigar shaped sulphides. This paper presents a number of examples illustrating these findings.

Jan 1, 2000