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By Qinbo Cao, Qianshan Peng, Heng Zou, Xingcai Yu

In this work, a new flotation strategy was proposed for the flotation of rutile. In this strategy, rutile was activated by Pb(NO3)2 and then floated with amyl xanthate (AX) as a collector at pH 8. Pb(OH)+ was the dominant lead species in the solution at pH 8 and is believed to be the major species reacting with the rutile surface. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) study revealed that the lead activation products were well distributed on the rutile surface, and AX− could further bind with the Pb atom on the Pb-activated rutile surface. In this regard, the Pb-activated rutile could be floated by AX. Furthermore, X-ray photoelectron spectroscopy (XPS) analysis indicated that Pb(OH)2 was generated on the Pb-activated rutile surface. The electron transfer during the adsorption of the AX− on the Pb-activated rutile surface was also investigated by XPS analysis.

By Qinbo Cao, Qianshan Peng, Heng Zou, Xingcai Yu

In this work, a new flotation strategy was proposed for the flotation of rutile. In this strategy, rutile was activated by Pb(NO3)2 and then floated with amyl xanthate (AX) as a collector at pH 8. Pb(OH)+ was the dominant lead species in the solution at pH 8 and is believed to be the major species reacting with the rutile surface. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) study revealed that the lead activation products were well distributed on the rutile surface, and AX− could further bind with the Pb atom on the Pb-activated rutile surface. In this regard, the Pb-activated rutile could be floated by AX. Furthermore, X-ray photoelectron spectroscopy (XPS) analysis indicated that Pb(OH)2 was generated on the Pb-activated rutile surface. The electron transfer during the adsorption of the AX− on the Pb-activated rutile surface was also investigated by XPS analysis.

By E Hawkins, S Sheldon

Block caving is becoming a more widely adopted mining method allowing for underground massive low grade orebodies to be extracted economically. Underbreak during cave propagation is difficult to predict in terms of recovery and is not well-researched due to the small number of caving operations. During mining of E26 Lift 2 (E26L2) block cave at CMOC Northparkes Mines, a wedge of high grade material failed to cave, even with the assistance of preconditioning and subsequent attempts to induce caving. The ultimate solution for recovery of the uncaved wedge was the establishment of the E26 sublevel cave (SLC), which commenced mining in 2015, with production following in 2016. The SLC provides approximately 1Mtpa to supplement the lowering grade of the current E48 block cave feed. Applying the sublevel caving methodology to recover block cave underbreak has proven challenging. The impact of the caving stresses and preconditioning of the wedge have caused production limitations requiring continual remediation throughout production of the E26 SLC. The dependence on remediation work created a roadblock to implementing precharging as the prevalence of brow loss raised concerns over the inability to hook up the charged ring. In 2018, a wireless initiation trial was completed in the E26 SLC over 24 rings. The trial showed that precharging was achievable in this environment and greatly improved the safety of charge up personnel.

Mar 15, 2021

By F. Agterberg

In his 1978 monograph ‘Lognormal-de Wijsian Geostatistics for Ore Evaluation’, Professor Danie Krige emphasized the scale-independence of gold and uranium determinations in the Witwatersrand goldfields. It was later established in nonlinear process theory that the original model of de Wijs used by Krige was the earliest example of a multifractal generated by a multiplicative cascade process. Its end product is an assemblage of chemical element concentration values for blocks that are both lognormally distributed and spatially correlated. Variants of de Wijsian geostatistics had already been used by Professor Georges Matheron to explain Krige’s original formula for the relationship between the block variances as well as permanence of frequency distributions for element concentration in blocks of different sizes. Further extensions of this basic approach are concerned with modelling the three-parameter lognormal distribution, the ‘sampling error’, as well as the ‘nugget effect’ and ‘range’ in variogram modelling. This paper is mainly a review of recent multifractal theory, which throws new light on the original findings by Professor Krige on self-similarity of gold and uranium patterns at different scales for blocks of ore by (a) generalizing the original model of de Wijs to account for random cuts; (b) using an accelerated dispersion model to explain the appearance of a third parameter in the lognormal distribution of Witwatersrand gold determinations; and (c) considering that Krige’s sampling error is caused by shape differences between single ore sections and reef areas.

Jan 1, 2015

This publication is the fourth in a series of miners? circulars covering various phases of accident prevention in bituminous-coal mines; these circulars constitute a text hook for courses of instruction on accident prevention in bituminous-coal minim. To these may be added material of particular interest in the field where the course is presented. Other circulars in the series are: Accident Statistics as an Aid to Prevention of Accidents in Bituminous-Coal Mines (Miners? Circular 47). Accidents from Falls of Roof and Coal in Bituminous-Coal Mines (Miners' Circular 48). Accidents from Hoisting and Haulage in Bituminous-Coal Mines (Miners' Circular 49).

Jan 1, 1946

By A. J. Hyett

Due to the ongoing revolution in electronics and communications more cost-effective geotechnical instruments can be manufactured using digital technology. This new generation of digital instruments have embedded microcontrollers that provide highly accurate and reliable measurement of geotechnical behaviour in real world units that can be immediately interpreted. Digital measurements can be transmitted across existing mine-wide wireless communication networks, interfaced directly with infra-red enabled PDA?s or PC?s, and parsed to memory by low-cost data-loggers.

Oct 1, 2004

By Fernanda da Silva Machado

Em um mundo de recursos naturais decrescentes, com a intensificação das indústrias automatizadas de todos os tipos (I4) e contínuo aumento da população, é necessário desenvolver melhores caminhos para a geração e distribuição de riquezas. Uma das alternativas para este objetivo é o conceito da Economia Circular. Este artigo apresenta um exemplo focado na intensificação do uso de resíduos de biomassa na produção integrada de aço exclusivamente baseada na combinação de reatores industriais existentes em um layout que favorece o conceito da economia circular. O ferro também é obtido do processamento tradicional de sucata, reprocessamento de resíduos de ferro e óxidos de ferro, como a escória, pequenos óxidos de ferro, reversos metálicos, resíduos da indústria siderúrgica integrada tradicional. Os resíduos de biomassa são provenientes da demolição de casas de madeira, e outros resíduos de biomassa, como limpeza florestal para evitar-se incêndios, resíduos de moinhos, paletes usados e qualquer outra fonte de biomassa. As combinações dos reatores tornaram-se possíveis devido à nova versão do processo de Carbonização Contínua, Carboval, um reator especialmente projetado da tecnologia Lambiotte tradicional, para produzir, de preferência, o carvão vegetal que possui as mesmas características necessárias para alimentar o Mini Alto Forno tradicional a base de carvão.

Oct 30, 2017

By C E. J de Ronde, J G. Scott

Economic gold mineralisation was discovered at Round Hill by Homestake NZ Limited in 1984 and was subsequently put into production by Macraes Mining Company Limited (MMCL) in 1990. The total mineral resource in 1990 was estimated at 41.4 Mt @ 1.42 glt at a 0.7g/t cut off, for 1.8 Moz of gold. Since project start up the mill has been upgraded twice to increase throughput and reached its current capacity of 3.2 Mtpa. At 31 December 1996, a total of 16.2 Mt of ore at average grade of 1.73 g/t has been excavated, yielding 655,000 oz of gold. MMCL began exploration along the Hyde Macraes Shear Zone in 1994. Since 1994, exploration has been successful with the discovery of over 3.5 Moz of gold. The resource now stands at 110 Mt @ 1.46 g/t gold for 5.1 Moz. This success has led to a planned expansion of the processing capacity to 9 Mtpa with the building of a new 6 Mtpa processing plant.

Jan 1, 1997

By Joselito Gonsalves dos Santos, Ivani Batista dos Santos Junior, Valeria da Silva Guandelinir, Daniel Rocha de Castro, Alexandre Jose Ramos Valentim

Este artigo tem como objetivo demonstrar os ganhos obtidos com automatizações de atividades de suprimentos de média complexidade e alto tempo de execução. Para atingir o resultado sem investimento, foram desenvolvidas automatizações através de programação em Visual Basic (VBA) e Scripts SAP, utilizando como plataforma o Microsoft Excel. A integração do Excel com o SAP se mostrou eficaz, possibilitando a execução de tarefas de forma automatizada em massa, aumentando a confiabilidade das informações e reduzindo o tempo total de execução das atividades em 67%.

Oct 1, 2019

By Gloria Fernández

La contaminación por drenaje ácido de mina se considera como la responsabilidad ambiental y económica más grande que actualmente enfrenta la industria minera. En ese sentido, se delimita las áreas afectadas mediante la perforación de pozos de monitoreo a través de un estudio geofísico previo. Por ello, el presente trabajo señala los métodos geofísicos como herramientas que pueden ayudar a delimitar y mapear las zonas afectadas por la contaminación proveniente de drenaje y filtraciones que va desde canchas de relave, pilas de lixiviación a minas abandonadas, etc.

Aug 25, 2002

By H. Yilmaz

Tensile strength testing has been one of the most common physical property testing methods of thin spray-on liner (TSL) products worldwide. However, the variety of products tested has been insufficient for comparison purposes. Specimen preparation procedures and test parameters such as curing time and loading rate are not reported well. Comprehensive tensile strength testing on 20TSL products and one plain shotcrete brand was performed over 28days of curing period. Detailed information on the test procedures with particular attention on the important aspects during sample preparation and test execution are provided. As expected, the tensile strength increases with increasing curing period. The test results make the categorization and comparison of liner products possible.

Jan 1, 2010

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

By Braden Lusk, Tristan Worsey, Nathan Rouse, Kyle Hall

Loading explosives up hole has challenges that are typically not seen in down hole explosive loading. Most explosives applications are not up hole. Lack of experience and technology can cause significant problems when loading explosives up hole. When results aren’t achieved, the blame is commonly put on the design when the true problems are unknown. Not knowing the cause of the problem causes drill and blast designs to be over engineered and very costly with little success. Being able to know and record key data is crucial to actually solving the problem. This paper goes over blast instrumentation that can be used to trouble shoot drill and blast problems in up hole explosives loading in underground mines. The tools and procedures used to trouble shoot include velocity of detonation recorder, borehole tracking, seismographs, and borehole camera. Each item will be discussed in detail with a case study to show the usefulness of the instrumentation. The operation discussed in the case study had issues pulling raises and had hang ups in the stope shots. These problems caused production slowdowns and costly remediation blasting that was not very successful. The case study is an underground gold mine that used modified sub-level caving with backfill as the mining method.

Jan 1, 2018

By Spooner H. W

The paper describes the search for mineral deposits in an area of 4,500 sq. miles of south-west Tasmania. The area is one of difficult access and the problem of speedy movement and maintenance of field parties was solved by the use of helicopters. The programme has followed a systematic pattern of the aerial photography of the exploration area with the preparation of photQmosaics and topographical base sheets from these mosaics. Geological maps were initially prepared by photogeological interpretation and making use where possible of pre-existing information. The maps produced were later checked by ground traverses. Geophysical maps were obtained by the use of airborne magnetic, electromagnetic and radiometric methods. Geophysical and geological anomalies were checked on the ground by a campaign using ground geophysical equipment in the former case and geological and geochemical work in both instances. Audio Frequency Magnetic and Induced Polarization techniques were used in an area which was covered by several hundred feet of Tertiary sediments.The campaign has reached the stage of the drilling of specific targets.INTRODUCTIONThis paper describes the activities of Lyell-E.Z. Explorations (L.E.E.), an organization which was formed in 1956 by the Mt. Lyell Mining and Railway Co. Ltd. and the Electrolytic Zinc Co. of Australasia Ltd. to explore for mineral deposits in an area of approximately 4,500 sq. miles in southwest and southern Tasmania. To provide the necessary personnel and equipment for this project the exploration resources of both Companies were pooled and augmented and a headquarters was established in Queenstown. The work was directed by a Committee of four made up of officials from both Companies; a review of this structure has recently been presented by Hall (1959).

Jan 1, 1960

By N. Shariatmadari

In recent years, determining bearing capacity of piles from in-situ testing data as a complement of static and dynamic analysis has been used by geotechnical engineers. In this paper, different approaches for estimating base bearing capacity of piles from SPT data has been compared and evaluated. A new method for pile base bearing capacity in sand is proposed using SPT records. Data averaging, failure zone extension, and plunging failure of piles have been addressed in the proposed approach. A data bank comprising 10 full scale static load tests on instrumented piles and 26 dynamic tests, analyzed with signal matching technique by CAPWAP software, was used for validation. The SPT data that was performed close to pile locations is also included in the data base. Comparison of current methods by error investigation with Log-Normal approach demonstrates that the proposed method predicts pile base capacity with more accuracy and less scatter in comparison to other methods.

Jan 1, 2006

By Fred N. Kissell

This handbook describes effective methods for the control of methane gas in mines and tunnels. It assumes the reader is familiar with mining. The first chapter covers facts about methane important to mine safety, such as the explosibility of gas mixtures. The second chapter covers methane sampling, which is crucial because many methane explosions have been attributed to sampling deficiencies. Subsequent chapters describe methane control methods for different kinds of mines and mining equipment, primarily for U.S. coal mines. These coal mine chapters include continuous miners and longwalls, including bleeders. Coal seam degasification is covered extensively. Other coal mine chapters deal with methane emission forecasting and predicting the excess gas from troublesome geologic features like faults. Additional coal chapters contain methane controls for shaft sinking and shaft filling, for surface highwall mines, and for coal storage silos. Major coal mine explosion disasters have always involved the combustion of coal dust, originally triggered by methane. Thus, a chapter is included on making coal dust inert so it cannot explode. Methane is surprisingly common in metal and nonmetal mines around the world, as well as in many tunnels as they are excavated. Accordingly, a chapter is included on metal and nonmetal mines and another on tunnels. Proper ventilation plays the major role in keeping mines free of hazardous methane accumulations. The ventilation discussed in this handbook, except for the chapter on bleeder systems, deals only with so-called face ventilation, i.e., ventilation of the immediate working face area, not ventilation of the mine as a whole. The omission of whole-mine ventilation was necessary to keep this handbook to a reasonable size and because a huge amount of excellent information is available on the subject.2

Jan 1, 2006

By S. N. Gurulaxmi, Veerendra Singh

The abstract discusses the increasing consumption of manganese ores and the need to utilize low-grade ores and rejects. The study focuses on developing a low-cost process using a cupola furnace to recover manganese values from these resources. The process involves smelting ore blends to produce high MnO slag and pig iron. The study investigates various factors to improve iron reduction and separation from MnO-bearing slag. The results show that the process can produce slag with MnO > 35% and Fe(t) < 5% using low-grade Mn ores. The process also achieves Fe reduction between 50 and 70%. The cupola furnace offers advantages like low cost and ease of operation, making it suitable for processing low-grade ores and rejects to produce synthetic MnO-enriched products for various industries.

Apr 1, 2022

By F. A. Rutledge

[An a part of the United States Department of the interior program for the development and use of Alaska raw materials, the Bureau of Mines is conducting an investigation of deposits of nonmetallic minerals accessible to the Alaska Railroad for use in building; materials is In the Alaska Railroad-belt area. The results of the investigations, to date, indices that raw materials for the preduction of brick products are in plentiful supply as cloy in the Anchorage area, as fire clay at Sheep Mountain, and as shale in the Healy Creek coal formations near Healy, Alaska.]

Jan 1, 1953

By D. Bogunovic

The U.S. coal mining industry consumes a significant amount of energy, primarily diesel fuel and electricity. The continuous global increase in energy demand, high energy prices, and environmental issues related to carbon dioxide emission represent a substantial challenge for the mining industry. This paper presents a result of research work on development of an integrated data environment system for analysis and control of energy consumption in a surface coal mine. A case study on an operating surface coal mine is carried out to demonstrate the practical application of the developed system. The research work presented here may be used by mining professionals to help provide the answers to the crucial questions of when, where, and how much energy is being used. This developed system represents a framework for efficient management of energy consumption. Key words: surface mining, coal, energy consumption, Information System.

Jan 1, 2009

How to Evaluate Crushed Rocks for Concrete Production

Sep 13, 2010