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By Fuzail Siddiqui

"The SIDMIN program aims at filling the mineral processor’s need to know the deportment of ‘minerals of interest’ not just ‘elements of interest’ that pass through the processing plants. Generally, chemistry is used as a tool of routine monitoring on site. Mineralogy, which is relatively much slower, is used more as a tool of research and post mortem investigations and these services are usually provided by a distant facility. The SIDMIN program enables site management to receive chemical and quantitative mineralogical reports on their critical samples daily, simultaneously and affordably.The author developed the SIDMIN program at ZCCM Nchanga Division where it continues to be a powerful tool for monitoring the efficiency of operations. Outlines are given of procedures for quick sample preparation and quantification of significant minerals in process samples. A specimen report is presented, which shows the format of reporting the contributions of individual minerals to metal losses at critical stages of the circuit. It is shown that SIDMIN provides timely information to management, about trends and abrupt changes in the quality of ore, and its processing, in a way never achievable by chemical analyses alone. This greatly helps in resolving the age-old problem of ‘bad ore’ or ‘bad operations’ on a day-by-day basis. For example increase in copper mica in the feed indicates excessive ore dilution during mining. Increased loss of free sulphides was traced to insufficient reagent conditioning time at the Concentrator. Persistent losses of leachable oxides at the Tailings Leach Plant were traced to inadequate leach residence time.SIDMIN is affordable because it can be implemented using basic optical microscopes, minimal quantities of micro-chemical reagents and custom trained site staff who demonstrate good colour perception and an ability to follow laid down procedures consistently."

Jan 1, 2000

By Martin C. Jones

This paper outlines the development of small diameter grouted piling, to deal with foundation problems in difficult soils conditions and in very restricted access areas. A number of applications are outlined to show the way in which these piles have been used over the last sixteen years in Canada. PICKERING GENERATING STATION - ONTARIO HYDRO UNDERPINNING OF SCREENHOUSE - TRASH DISPOSAL AREAS Between 12th July and 29th September 1971, 40 small diameter grouted piles were installed in the screenhouse at Pickering Generating Station. Access was extremely restricted as the screenhouse had been completed and the majority of mechanical equipment had been installed. The two ends of the screenhouse had been built on granular fill which overlies till and shale bedrock and settlements had been observed which it was decided had to be halted even though the rate of subsidence had decreased. Two diamond drills were employed to install 8 inch

Jan 1, 1987

In 2007, a total of 278 metal mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 Metal mines were the smallest mining commodity sector, comprising 1.9% of all mining operations. ? Gold mines comprised 44.6% (n=124) of all metal mining operations. Other common types of metal mines were iron ore (n=36; 12.9%) and copper ore (n=35; 12.6%). ? Nevada had the largest number of metal mines (n=45; 16.2%), followed by Alaska (n=28; 10.1%).

Aug 1, 2009

By Dan A. Brown

Outline ? Basic Concept of ACIP Piles ? Factors Affecting ACIP Pile Performance ? Applications: - Favorable Conditions - Unfavorable Conditions ? Design for Axial Loading ? Lateral Loading Considerations ? Summary & Conclusions

Jan 1, 2004

By D. Das, B. K. Nandi

The present study focuses on utilising the electrocoagulation (EC) process for the treatment of process water generated in an iron ore beneficiation plant for safe discharge and reuse. Removal of heavy metals like Fe, Cr, Cu, Zn, Mn and Pb which was found in higher concentration along with some other impurities exceeding the permissible and discharge limit were attempted. The influence of different electrode material, current density, inter-electrode distance, and solution conductivity was explored for effective removal of the metal ions. Experimental results infer that almost 99.95% Fe, 97.77% Cr, 73.44% Cu, 99.34% Pb and 88.69% Mn was removed using aluminum electrodes at monopolar mode at a current density of 68.50 A/m2, inter-electrode distance of 1 cm and solution conductivity of 1.033mS after 60 min of EC. In addition, removal of other toxins like TDS, turbidity, salinity and conductivity etc. was also assessed during the process. Removal of such heavy metal ions by EC was found to follow 1st order kinetics with electric energy consumption of 3.93 kWh/m3, electrode consumption of 0.1191 kg/m3 and operating cost of 0.6115 US$/m3 respectively. Keywords: Fe removal, electrocoagulation, Al electrode, turbidity

Jan 1, 2020

By P. Moyo, S. Dixon, R. Norcross

The separation and recovery of copper from cyanide solution has been investigated since the early 1900s. The precipitation of copper using sulfide ion was patented in 1911 by Williamson, published by Leaver & Woolf of the USBM in 1931 and Cyanamid in 1960s. The current practice of sulfide precipitation is used in various processes such as “SART" for cyanide regeneration and copper recovery. The precipitation of copper sulfide requires the pH of the clear solution to be in the range of 4-6. The precipitated copper sulfide can be sold to smelters. Alternatively, copper cyanide can be precipitated from clear solutions in the pH range of 2-3. However, selling copper cyanide is challenging because of its cyanide content. Past work has focused on the use of boiling sulfuric acid to convert copper cyanide to copper sulfate as published by Seracini in 1991. This paper describes a simple process to convert copper cyanide to copper oxide using sodium hydroxide at ambient temperatures. The cuprite can be sold to smelters or used as a feed to an electrowinning circuit to produce copper cathodes. The process provides an effective method to recover copper from cyanide solutions with a lower capital requirement.

Mar 2, 2022

By J. Patterson

"Acid Mine Drainage (A.M.D.) formed from oxidation of disposed pyritic wastes presents a potential pollution hazard for Equity Silver Mines Limited and the mining industry in general. Failure to collect and treat these acidic effluents can eventually affect the quality of receiving streams and endanger aquatic life forms. Treatment and discharge of A.M.D. to the receiving environment must comply with stringent anti-pollution laws.Wastes mined at Equity Silver Mines Ltd. are predominantly acid generating and must be handled according to a materials management plan to minimize impact on the environment. Effluent collection and treatment facilities have been constructed to address the short term environmental concerns with reclamation and research programs being developed to address and monitor abatement measures for control over the long term.The purpose of this paper will be to offer a brief overview of these measures. Key topics for discussion will be: kinetics of Acid Mine Drainage, acid generating potential, water treatment and sludge handling, special wastes, waste dump construction, waste rock amendments, bacteriocide research, simulations, and reclamation measures. Programs designed to evaluate impact on the receiving environment, although they form an extensive part of the program, will not be discussed in this paper.INTRODUCTIONEquity Silver Mines Limited is located in the Central Interior of British Columbia, within the Omineca Division, 35 kilometers southeast of Houston Mining and approximately 575 kilometers by air north-northeast ofVancouver (Figure 1).The deposit consists of three economic mineralized zones: The Southern Tail, Main and Waterline Zones. Mining of the Southern Tail commenced in April, 1980 and was completed in the first quarter of 1984. Main Zone production was initiated during the last quarter of 1983 and the Waterline Zone remains undeveloped to-date. Remaining reserves are in the order of four years contingent on favourable metal prices. The three deposits (Figure 2) occur within a window of interbedded volcanic and minor sedimentary rocks. The older volcanic sequence is bounded on the west by a small granite-like stock and on the east by a gabbro-monzonite complex. All are overlain by a series of younger lava flows."

Jan 1, 1988

By James S. Browning

Recovery of fine mica from a sample of impounded tailing from the Dixie Mines, Inc., crushing and screening operations, Heflin, Ala., was investigated to determine if plant losses of mica could be reduced while econmically producing a commercially acceptable mica concentrate. Conventional wet-tabling and agglomerate-tabling methods yielded concentrates assaying about 95 percent mica from the tailing that contained 17 percent mica. Products containing about 98 percent mica and accounting for mica recoveries of 86 percent were obtained by flotation, using as reagents sulfuric acid, kerosene, and coco amine acetate (a mixture consisting chiefly of dodecyl and tetradecyl amine acetates). The results of the batch flotation tests were verified by tests in a small continuous flotation pilot plant.

Jan 1, 1963

By Clarence O. Babcock

A simple robust rock bolt load gage was tested in the laboratory to define its characteristic behavior and to obtain a measure of its performance. The gage uses three vibrating wire sensors crimped 120 degrees apart into the outer surface of a hollow cylindrical steel tube. The resonant frequencies of the wires change as the gage is loaded. This change is read with a Creare meter developed for the Bureau on a previous contract to read borehole stress gage results. A statistical analysis of data obtained defines the variables influencing results. A U. S. patent (3,914,992) assigned by the author to the Department of the Interior was granted October 28, 1975.

Jan 1, 1976

The separate outputs of Burma and India in 1937 were 274,664,365 gal. valued at £4,474,147 and 75,657,857 gal. valued at £1,030,591, respectively. The corresponding figures for the year 1938 were 263,823,-265 gal. valued at £3,766,810 and 87,082,371 gal. valued at £1,234,563, respectively, which is a slight increase in total quantities but a fall in value for the combined outputs of Burma and India. The appreciable increase from India in 1938 is due to an increase of over 11 million gallons from Attock and a little from Digboi, while the decrease from Burma is due to a fall of nearly 9 million gallons from Yenangyaung, over 3 million gallons from Yenangyat (and Lanywa) and half a million gallons from Minbu (Table 1). The 'amount' of gasoline produced from natural gas during the year 1938 was 10,587,291 gal. in Burma and 496,163 gal. in the Punjab.

Jan 1, 1940

The separate outputs of Burma and India in 1937 were 274,664,365 gal. valued at £4,474,147 and 75,657,857 gal. valued at £1,030,591, respectively. The corresponding figures for the year 1938 were 263,823,-265 gal. valued at £3,766,810 and 87,082,371 gal. valued at £1,234,563, respectively, which is a slight increase in total quantities but a fall in value for the combined outputs of Burma and India. The appreciable increase from India in 1938 is due to an increase of over 11 million gallons from Attock and a little from Digboi, while the decrease from Burma is due to a fall of nearly 9 million gallons from Yenangyaung, over 3 million gallons from Yenangyat (and Lanywa) and half a million gallons from Minbu (Table 1). The 'amount' of gasoline produced from natural gas during the year 1938 was 10,587,291 gal. in Burma and 496,163 gal. in the Punjab.

Jan 1, 1940

By Isadora Dias Perez

Em vista da crescente geração de efluentes contendo metais, busca-se por técnicas sustentáveis capazes de recuperá-los, devido à toxicidade e ao valor econômico agregado. Os metais ainda contribuem com a poluição dos recursos hídricos. Desta maneira, o presente trabalho investiga a adsorção dos metais presentes num efluente produzido na mineração (licor) do níquel, através da resina quelante de troca iônica Dowex XUS43605. Os experimentos foram realizados em bateladas, variando pH, para verificar a captação pela resina do alumínio, cobalto, cromo, cobre, ferro (III), magnésio, manganês, níquel e zinco presentes no licor. A concentração dos metais na solução foi obtida pela técnica de espectrometria de fluorescência de raios-x por energia dispersiva (EDX). Os resultados mostram a capacidade de remoção dos metais pela resina, destacando 83% de adsorção do cobre e 7% do níquel, considerando 2,0 pH e tempo de contato 2h. Portanto, o estudo demonstra que a resina de troca iônica pode ser utilizada para tratar efluentes, em especial, de mineração.

Aug 17, 2017

By Jacqueline A. McClaskey

The U.S. Bureau of Mines (USBM) Information and Analysis Directorate collects worldwide data on virtually every commercially important nonfuel mineral commodity. These data form the base for tracking and assessing the health of the minerals sector of the U.S. economy. The USBM's data collection activity was instituted by the 47th Congress in an appropriations act of August 7, 1882 (22 Stat. 329), which placed the collection of mineral statistics on an annual basis. The most recent authority for the USBM survey activity is the National Materials and Minerals Policy, Research and Development Act of 1980 (Public Law 96-479, 96th Congress). This act strengthens protection for proprietary data provided to the U.S. Department of the Interior by persons or firms engaged in any phase of mineral or mineral-material production or consumption.

Jan 1, 1995

By A. Mboma

Keywords: Furnace, decommissioning, care and maintenance, re-start, funding, nickel Bindura Nickel Corporation (BNC) operates two nickel mines, and treats concentrates from these mines as well as toll concentrates from the region around its Bindura Smelter and Refinery (BSR) complex. At the smelter, concentrates of at least 5% nickel content are blended and dried to 4% moisture in a coal-fired rotary kiln. Matte smelting of concentrate is carried out in a six-in-line electric arc furnace, where the furnace slag is granulated and discarded. Furnace matte is transferred via ladles into Peirce-Smith converters, where, after granulation, a leach alloy containing 68%Ni, 20%Cu, and 6%S is produced. Converter slag is recycled via the matte-smelting furnace. The onset of the global economic recession towards the end of 2008 resulted in a collapse of metal prices, worsening the local situation that was already marred by unfavourable macro-economic conditions in Zimbabwe. As a result, BNC mines were put on care and maintenance in November 2008, followed by Bindura Smelter and Refinery in February and March 2009 respectively. The business environment has since changed, and BNC is getting ready to re-start the plant. This paper describes the decommissioning of the Bindura furnace, asset preservation during the care and maintenance programme in the past two years, and preparation for starting up of the Bindura smelter in the near future.

Jan 1, 2011

By D. F. Suarez

Spontaneous nodulation leading to growth of well developed glossy spheroids (generally hemispheres) of up to 0.06 cm width in 120 min has been observed during copper electrodeposition with certain levels of glue, thiourea and C1-. Thiourea alone can produce spontaneous nodulation but addition of glue and/or Cl- is required for rapid and sustained growth. In most cases once the glossy nodules develop they consume the majority of the copper deposited; thus, the specific current densities (and hence copper electrodeposition rates) on the glossy nodules are about an order of magnitude or, more greater than on the adjacent planar surfaces. The texture of the adjaoent planar surfaces is not glossy in appearance but is well faceted showing the usual deposition grain structure for such additives. Cathode potentials when spontaneous nodulation occurs are about TOO my more negative than with usual copper electroplating. This fact associated with evidence of extremely high levels of cathode surface passivation based on cyclic voltammograms indicates that the conditions which lead to spontaneous nodulation result from a very tightly adsorbed additive surface film. This film breaks down in specific points initiating the glossy nodules which then grow at extremely rapid rates. Current density is also important in spontaneous nodulation. At equal deposition times a current density of 21.5 mA/cm produced much larger glossy nodules than at 48 mA/cm2. The surface concentration of the glossy nodules was much greater in the latter case, however. The role of current density is still not well understood. The role of it as well as the relative roles of the three additives, thiourea, glue and Cl- in spontaneous nodulation is presented. Preliminary results and some possible correlations of these to help explain spontaneous nodulation are presented. It is believed that tankhouse upsets where cathode nodulation occurs may be related to this phenomenon.

Jan 1, 1987

By J. X. Wu

An investigation on the seismic damage to buildings with pile foundations in Tianjin region, was conducted after the earthquake which hit Tangshan in 1976. It showed that most pile-founded buildings have an excellent aseismic capacity. In this paper, several pile-founded projects suffering the seismic damage are introduced as examples, simplified calculations are made of the vertical bearing capacity of pile foundations and of the horizontal seismic force, and suggestions are presented in conection with the design of pile foundations in the liquified ground soil. The paper shows a frame structure which has a plie foundation with a box-shaped base. Analyses if its response to the earthquake has been carried out in accordance with the F.E.M. and results have been obtained.

Jan 1, 2010

By Larissa Rodrigues de Carvalho Rocha, Mauro Vivaldino Fernandes, José Eduardo da Silva Moreli, Beatriz Fausta Gandra, Adriano Cesar Carvalhido

No atual cenário siderúrgico, o prolongamento da campanha de um alto-forno tem sido prática usual em diversas empresas. Nesse contexto, a Usiminas tem realizado diversas ações de preservação dos altos-fornos, conciliando com a manutenção da competitividade. Particularmente, o Alto-Forno 3 da Usina de Ipatinga passou por duas trocas de staves, em 2015 e 2018, totalizando a substituição de 68 peças. No presente trabalho é apresentado o planejamento e a execução do retorno operacional após a 2ª troca de staves, destacando as contingências adotadas e lições aprendidas face às ocorrências que impactaram o cumprimento do cronograma previsto. Essa intervenção possibilitará a postergação da reforma para 2021, em alinhamento com as diretrizes da empresa e garantindo uma estabilidade operacional, fundamental para os cumprimentos e superação das metas.

Oct 1, 2019

Jan 1, 1933

By C. W. Vierrether

Mineralogical analysis contributes directly to the selection of applicable beneficiation techniques for a given site. Tentative remediation methods for use on the Sharon Steel tailings in Midvale, Salt lake County, UT, were determined in part by mineralogical characterization. A systematic characterization scheme was employed to identify mineral species, mineral associations, and grain size. This paper presents the mineral content and distribution data collected for site characterization. This data was used to determine areas that were representative of the total tailings at the Sharon Steel site. Although this was the main focus of characterization, other useful information was obtained. The approximate location of "old jig tails" was identified and insight on possible arsenic, mobility through the pile was also obtained from the mineralogical study.

Jan 1, 1991

By B Belle

In a predrained gassy coalmine, ventilation control plays a secondary role to the longwall (LW) goaf drainage systems to safely manage panel return gas levels. Typically, the LW specific gas emission (SGE) estimation models provide anticipated goaf gas emissions and arriving at required gas drainage capacity for various coal production scenarios. A study comparing the various LW goaf gas hole spacing patterns with weekly production rates of up to 270 kt/w of an operating mine with high SGE rates (~20 m3/t) was carried out. The goaf capture efficiency of LW panels ranged from 64 per cent to 85 per cent. For the first time, gas content of upper seam data post LW retreat were used to verify the current SGE prediction models. This study has shown that an average of 50 m goaf spacing is optimal for management of high production retreat gassy LW panels in presence of multiple upper and lower seams with gas emission zone influence reaching up to 200 m above workings. Due to the horizontal stress direction related geotechnical issues, goaf hole failures just behind the LW face is a recurring challenge resulting in significant and immediate increase in LW panel return gas levels. This paper highlights the shortcomings of current SGE prediction models for goaf gas estimation, and evolution of 50 m goaf hole spacing embedded in design process in managing the LW tailgate gas levels.CITATION:Belle, B, 2017. Optimal goaf hole spacing in high production gassy Australian longwall mines – operational experiences, in Proceedings Australian Mine Vent Conference 2017, pp 15–26 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017