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By S. McGinn

The Brunswick Mine Diesel Particulate Filter Study was one of several research projects initiated by the Diesel Emissions Evaluation Program (DEEP). The study was carried out at Noranda?s Brunswick Mine in Bathurst, New Brunswick by Noranda Technology Centre and Brunswick Mine personnel with the collaboration of Natural Resources Canada - Canada Centre for Minerals and Energy Technology (CANMET), National Institute of Occupational Safety and Health (NIOSH), Andreas Mayer of VERT, and diesel particulate filter (DPF) system suppliers. The study began in early 2000. Field evaluations continued for 20 months. The final report?authored by Sean McGinn?was submitted to DEEP in the Autumn of 2003.

Jan 1, 2004

By R. G. B. Pickering

The hard rock gold and platinum mines in South Africa have seen little development in the technology of mining. Holes are still drilled in the rock?though the latest water hydraulic rockdrills will complete that task in two minutes compared with the eight hours for hand drilling. Charging up is with far safer explosives and with available initiation systems it is no longer necessary to run up the face lighting each fuse. Movement of rock in the stope is predominately by means of scraper buckets and scraper winches?these were first introduced in the 1920s. Support is still mainly rock, either in situ pillars or backfill, or alternatively wood. Just as the mining process has changed very little it is hardly surprising that the productivity of mining is also relatively unchanged. Major efforts have been made to mechanize the mining process. However, most of the narrow reef mines where ?trackless mechanized mining? was introduced in the early1980s have reverted to conventional mining. In the wider reefs mechanized mining is the option of choice, unfortunately most of the gold and platinum mines have very narrow reefs that are not suitable to ?off the shelf? equipment. The move to introduce room-and-pillar mining into the narrow UG2 reefs is at the expense of mining more waste with the reef, fortunately it appears that appropriate waste and reef separation processes are available. Room-and-pillar mining followed by long hole drilling and blasting of a narrow slot of reef out of the pillars currently appears to offer the best of both worlds?maximum reef recovery with minimum waste dilution.

Jan 1, 2002

By H. L. Gilbert

Improvements in production of high-purity chromium metal by magnesium reduction of anhydrous chlorides and by hydrogen treatment of electrolytic chromium are reported. Hydrogen-treated chromium has been arc-melted, and the arc-melted material has been successfully forged, rolled, and swaged. The material also has been forged at liquid-air temperatures. X-ray and metallographic studies indicate the recrystallization temperature of rolled chromium sheet to be about 750° C. Preliminary investigation of hot-bending characteristics of rolled chromium sheet shows the minimum bending temperature to be about 325° C. The heat resistance of chromium has been investigated.

Jan 1, 1952

By Gerald T. Homce

Accidental contact of overhead electrical power lines by mobile equipment is a leading cause of occupational fatalities in the United States, accounting for 20% of on-the-job electrocutions. Overhead electrical power line proximity warning devices (PWDs) are intended to warn personnel if mobile equipment moves within some preselected minimum distance of an energized overhead electrical power line. Two commercially available PWDs were tested at the National Institute for Occupational Safety and Health?s (NIOSH) Pittsburgh Research Laboratory (PRL). The objective of the tests was to document performance capabilities and limitations for these PWDs by identifying factors that can influence their operation. The two PWDs evaluated in this research are the SIGALARM Model 210 marketed by Allied Safety Systems, LLC, and the ASE Model 2100 from Allied Safety Engineering. Both of these devices operate by measuring the electric field present around energized power lines. The PWDs were installed on a government-owned 22-st (20-mt) rough terrain crane. A purpose-built test site used for this research at PRL allowed operation of the crane near a variety of power line configurations operating at up to 25 kV. Most of the tests involved positioning the crane adjacent to one or more overhead power lines, adjusting sensitivities of the PWDs to alarm when the crane boom was approximately 20 ft (6.1 m) from the power lines, swinging the crane boom toward the lines under a wide variety of test conditions, and finally, for each unique set of test conditions, documenting the deviation from 20 ft (6.1 m) for actual alarm activation. Test results show that several factors can adversely affect PWD performance. PWD alarm accuracy generally deteriorated when operating with a boom position significantly different than that used for the device?s last sensitivity adjustment. Another factor that can affect PWD performance is configuration of the overhead power line(s) involved. Accuracy of alarm activa­tion distances was best for simple single-circuit installations, but degraded for multiple circuits on the same poles. This degradation was slightly greater for installations with different voltage levels and/or a combination of vertical and horizontal conductor arrangements. Performance also degraded for crane operation between two intersecting power line installations, especially for intersecting lines at different voltages. An additional aspect of power line configuration shown to influence PWD accuracy was phase sequence on the power line circuit(s). Specific phase con­ductor arrangements and combinations, particularly in multiple circuit installations, resulted in either improved or degraded accuracy.

Jan 1, 2008

By Derek J. Lennon

Ground conditions in central Glasgow generally comprise loose granular deposits overlying stiffer soils. CFA piling would normally be preferred for urban sites in these ground conditions, but flighting of the superficial deposits has on occasions resulted in building damage. Over the last five years rotary bored piling with vinyl polymer support fluid has proved to be an economic alternative to bentonite slurry. Two case histories in central Glasgow are described in this paper, one for piles founding in granular soils and one for piles founding into bedrock. A comparison is made between the methods required for disposal of the liquid waste from bentonite and vinyl polymer slurries.

Jan 1, 2006

By Laura Bustemante, Bruce Vandenberg, Fred Huettig

Recent advances in solid-state, field portable, fast framing video camera systems and PC based frame capture hardware now allow blast imaging up to 1000 frames per second. Up to 8 seconds of data can be stored directly into the unit, downloaded to a PC or archived to a standard VCR without data compression. Since no film processing is involved, motion analysis can be performed instantly and on-site within a few minutes. This paper will describe the design features and applications of the KineView 1256P system and compare these with the analogous aspects of fii based cameras.

Jan 1, 1998

By Douglas Rudenko

Have you ever had a neighbor complain about a blast one day, but says the next day’s blast was better, even though the Peak Particle Velocity (PPV) increased? How about neighbors that complain about a small trimming shot, but don’t complain about a big production shot? Have you ever reduced the pounds/delay and gotten more complaints ? Mine operators are often bewildered when trying to correlate blast design parameters to homeowner complaints. When complaints come, standard practice is to set up a seismograph in the neighbor’s yard to monitor the blast. Immediately after the blast, the neighbor usually reappears from the house wanting to know the seismograph reading. When told that the PPV was 0.1 in/set, well below damage levels, the homeowner explodes saying “Your machine is wrong”. Perhaps he is right. Understanding why people complain about blasting is not about PPV, it’s all about structural response. People could care less about how much the ground vibrates; they only care about how much their house vibrates. In this paper we will examine the primary factors that control structural response. Through the use of a large array of digital seismographs, the effects of two production blasts on a community surrounding a quarry are studied. The predicted structural response resulting from each blast is calculated at 175 seismograph locations. The predicted response is then correlated to previous research on human perceptibility to vibrations. The results of this analysis and correlation give a better understanding of what the residents actually feel in their homes. The detonations of two single-hole signature blasts are also recorded by the array of seismographs revealing the dynamic characteristics of the geology ‘surrounding the quarry. Once the influence of the geology was understood, blasts were configured to disrupt the natural rhythm of the site through the use of millisecond delays.

Jan 1, 2000

This publication summarizes, for potential contractors and all other interested parties, the research and development of in-house and contract projects programmed by the Bureau of Mines for fiscal year 1983 (October 1, 1982-September 30, 1983) under its Health and Safety Technology program. The objective of these projects is to provide an ordered and sequenced series of advance toward the Bureau's overall goal of providing the systems technology required to create a more healthful and safer working environment for the Nation's mining and minerals processing workers.

Jan 1, 1982

By Zhou Lu-Jian

The Port of Shekou is situated at Shenzhen Bay on the east bank of Lingding Ocean. Its coastline is about 6 km long and the water depth near the shore is Favourable. Across the bay is the ' New Territories " of Hong Kong. The port is at a distance of 22-23 seamilesaway from center of Hong Kong and 80 seamiles to Huangpu Harbour of Guangzhou, its highway links with Shen-Guang Highay. Since 19 79 China Merchants Group of the Transportation Department, began to set up Shekou Industrial Zone, the port has been developing and flouri­shing in business. With 15 large or small berths in all, the present portline is 2600 m, and the annual cargo throughout is over 3,000,000 tons and the annual passenger traffic is about 2,000,000 persons. Equalling a medium-scale seaport, it has been officially approved as an oceangoing transit port by the ministry of Transportation. The construction of Shekou port is chara-terized by the self-collected funds and the short construction period. In view of this, the optional plan of the port structure must serve the requirements of simplicity in struture, economy in mate­rial and speed in construction. That accounts for the most application of the sheet piling type to the port in Shekou. Once the project was approved, the cons­truction started. Only within an average period of 7-8 months, a deep water pier was completed and put into operation, which covered series of processes from exploration, designing, tender for con­struction to completion.

Jan 1, 1991

By David A. Hall

We present an analysis of the propagation in a uniform tunnel of semi -circular cross section that contains two axial conductors. In particular, we show that, even if one of these conductors has high ohmic loss, one of the two propagating modes has relatively low attenuation. This corresponds to the situation where an unloaded dedicated wire is used to improve radio frequency communication in a mine tunnel that contains a heavily loaded trolley wire.

Jan 1, 1978

By Randall M. Wheeler

Using Computer software to analyze and interpret blast vibration effects has never been so practical. Fully digital seismographs and powerful desktop and portable computers have led to the development of fast and easy to use analysis software. This workshop will focus on new Microsoft Windows-based blast vibration analysis programs developed by White Industrial Seismology, Inc. The Windows point and click graphical environment is ideal for developing full-featured and yet intuitive software.

Jan 1, 1994

By Arpit Parikh

"Ground Water or Pore water pressure development in Sandy Soil formation is Critical situation in foundation analysis and design.Moreover it become severe while associated with higher liquefaction probability in river bank areas. It is difficult to find cost optimized solution for liquefaction mitigation under limited budget allocated for the project. Here in these research paper the attempt has been made to have clear picture of liquefaction by using various techniques and field tests. And its mitigation by suitable foundation type. In Bangladesh, On Bank of River Meghana, Power plant structures are proposed. The particular site is full of fine sand having partial silt throughout from EGL to 55 m depth. Hence in addition to Conventional Boring / Drilling operations, CPLT, SCPT, SCHT and PMT had been performed to arrive deterministic effect of liquefaction. By use of Geologismiki software and some excel based programs developed which indicates that Certainly liquefaction occurs under the event of earthquake. By Checking past records of Bangladesh we found, there are small magnitude earthquakes are inevitable and frequent. Hence fourth to overcome the bad effect of liquefaction, the deep pile foundation -Driven Pre Cast Solid Square Pile of 400 mm dia. had been suggested for various types of power plant structures. Which densify the soil and ground will improve in resisting liquefaction.1. INTRODUCTIONA Detailed Geotechnical/Foundation design Analysis had been done to arrive at optimum foundation design solution in highly probable liquefaction zone of Silty Fine Sand near Dhaka City of Bangladesh for proposed 750 MW Cyclic Power Plant. Hence about 24 no. of (Borehole) Boring and Drilling up to depth of 55 m from existing ground level has been carried out. Additionally, 09 nos. of Static Cone Penetration Test (SCPT), 02 Nos. of Dynamic Cone Penetration Test (DCPT), 02 Nos. of Pressure meter test (PMT), 02 nos. of Cyclic Plate load test (CPLT) of suitable capacity with 06 nos. of Seismic Cross Hole Test (SCHT) in boreholes had been carried out. The purpose of PMT and SCHT was to have clear idea about the Seismic behavior - knowhow of site. According to Basic principles of Soil Mechanics and foundation design, it is proved that PMT & SCHT are dynamic test. These tests stimulate field condition of occurrences of earthquake. In later stages of analysis, it is found that site have high probability of liquefaction through use of Geologismiki – Liquefaction Analysis Software. Author of these research paper also felt earthquake vibrations – strong aftershocks during site study where Epicenter of the earthquake was in Myanmar during month of august 2016."

Jan 1, 2017

By Erkan Bayrak, Serkan Erkara, Ozkan Duzgun, Ekin Gungor

This paper presents part of the outcomes of the drill and blast optimization project carried out at Kisladag Gold Mine in Turkey. Kisladag Gold Mine is the largest gold mine in Turkey with a low-grade, bulk-tonnage, open pit operation that uses heap leaching for gold recovery. After blasting, the ore is fed to a three-stage crushing circuit which prepares crushed ore approximately -10 mm (0.39 in) for heap leaching. Crusher downtime analysis showed that blocky material and insufficient feed are causing significant downtimes with the primary crusher. This was supported by the fragmentation data collected to date. It was decided to initiate a fragmentation project to understand the variation in the run-of-mine (ROM) size with a view to provide a consistent feed to the crushing circuit. The study includes the analyses of the ore strength and structure, image analysis of the fragmentation pictures acquired from blasts, blast auditing and quality assurance and quality control (QA/QC) analyses. During this project, over 200 fragmentation pictures were acquired from 47 blasts to optimize ore and waste blasts. Ore strength varies between 30 and 120 MPa and rock quality designation (RQD) ranges between 30 and 100. A site-specific fragmentation model was used to calibrate the fragmentation for blast domains formed. In addition, alternative cases were simulated to achieve blasts designs with consistent ROM fragmentation size distribution. Alternative blast designs that include stemming length and powder factor changes were suggested. Long stemming length, drill cuttings use, free faced blasts, small shot sizes and poor stemming length control were some of the key issues causing coarse fragmentation.

Jan 1, 2015

By Donald Leroux, Asim Tuzun, Simon Gariépy, Luc Lachance, Hayley Halsall-Whitney

"The importance of coherent material balance results has long been recognized by mining and metallurgical companies. Although this is still true nowadays, various stakeholders are increasingly concerned about the origin and the accuracy of the reported numbers. The last decade has shown that most metallurgical accounting concerns can be addressed by making two important changes to plant performance monitoring practices. First, introducing data redundancy into the metal balance procedure allows the estimation of measurement errors. Second, the migration from spreadsheet-based to relational database based systems brings transparency, data integrity, traceability and auditability into metallurgical accounting. Relational databases also facilitate the production of reports that metallurgical accountants must issue routinely. Recognizing the caveats of the spreadsheet-based metal accounting method they had been applying for years, Strathcona decided to switch to a commercial relational database system in 2008. For the most part, the migration was seamless. Some challenges were raised but they could all be overcome and outweighed by benefits gained from day-to-day utilization of the system.INTRODUCTION Metal accounting (Morrison, 2008) has always been essential to high-quality corporate governance of mining and metallurgical companies. Although the importance of coherent material balance results has long been recognized, various stakeholders are increasingly inquisitive about how the reported numbers were obtained and how much accuracy can be attributed to them. This accrued scrutiny is obviously no stranger to the corporate governance tightening that happened through the years in response to outrageous accounting scandals. It is also in continuity with securities laws (such as NI-43-101 in Canada) that were passed to protect the public from other market fraud. Recognizing the importance of spotless metal accounting in their reports to the public, a group of global mining companies gave AMIRA International the mandate of developing a set of rigorous yet practical metal accounting guidelines for the mining and metallurgical industry. The AMIRA P754 project was launched in 2004 and the first version of the resulting Code of Practice was released the following year. Since then, the Code was reviewed twice and revised releases were issued (AMIRA, 2007). While some parts of these guidelines are in continuity with current commonplace practices, other parts recommend changes to inherited practices that may be significant. For example, they highlight the importance of data redundancy (Lachance & Flament, 2011) which in many operations is either already available but unexploited or achievable with reasonable efforts. These guidelines also stress the importance of state-of-the-art metal accounting systems, such as those based on relational databases, which are secure and entirely auditable by a Qualified Person. Because most spreadsheet software packages allow data and formulae to be modified at any time, without a trace and anonymously, they do not meet these requirements."

Jan 1, 2012

In this address I look back over the past 40 years of mineral exploration in New Zealand û essentially the period since the Second World War (ie since 1945). It was the period of my personal involvement, and indeed of the personal involvement of a number of you. Luckily it was aperiod of great interest and activity. In the previous 50 years, virtually nothing had happened, and it is kindest to draw a veil over that period. In the very important earlier 40 years (1855 - 1895) the New Zealand gold rush occurred. That must have been a fascinating, rewarding period, which has been thoroughly documented by better historians than myself. I will simply comment firstly that its mineral explorers (gold-prospectors) were very successful indeed, and found most localities of the minerals they sought, in spite of using very different methods from ours of today. Secondly, they were preceeded by one of Maori exploration, which searched for a much restricted list of minerals, but succeeded in finding virtually every locality we know of today. The explorers of both of these early periods were obviously highly successful, but, in the time available, I must restrict myself to the period since 1945. I am currently editing the effective up-dating of Gordon WilliamsÆ 'Economic Geology of New Zealand' (1974). It covers the last 12 years or so. Many of you are contributing to that volume û both as authors and as referees û and I would like to take this opportunity of thanking you all. Although this new volume excludes the energy field, many of us have been involved in it, and I am therefore including energy minerals in this review, as Williams did in 1974.

Jan 1, 1987

By D. Settles, R. Rose, P. L. Dunn

"A new mineral sands operation is being developed in Georgia by Southern Ionics, Inc. (SII). Prevailing mineralogy and certain design constraints required detailed testing and circuit analysis to create a robust separation processes. The floating wet concentrator plant (WCP) and mineral separation plant (MSP) flow sheets were designed based on historical testing information and recent SII test campaigns on various composite feed samples. The flow sheets were finalized through rigorous process and orebody sequence modeling.The process uses traditional physical separation equipment; however a new MT spiral, the MG12, was selected for use on board the WCP for roughing duty. The MG12 spiral is a two-stage, twelve-turn spiral that has been proven to achieve very high recoveries of heavy minerals. The floating plant includes feed desliming operations, a central MT surge bin for optimum spiral circuit feed control and ancillary operations for concentrate and tailings handling. Scrubbed heavy mineral concentrate (HMC) is then transported to the MSP for concentration of the titanium and zirconium bearing mineral fractions.The testing, flowsheet development, and plant design will be described and explained, and a brief summary of the current project status will be given.IntroductionSouthern Ionics Inc. (SII) is a privately held chemical manufacturing company, founded in 1980 by Milton Sundbeck. SII focuses primarily on the sale of specialty and intermediate inorganic chemicals. Core markets include cement and refinery catalysts, molecular sieves, zeolites, pulp and paper, pharmaceuticals, TiO2 and water treatment. SII is built on the four cornerstones of service, quality, technology and delivery with all SII facilities ISO certified and key products used in potable water treatment certified to NSF standards. SII owns and operates its own transportation fleet and is focused on being a low cost producer, committed to safety and the environment."

Jan 1, 2015

By K M. Brodie, D I. K McLeod, J Ruddock

Environmental incidents involving mine tailings and waste rock inevitably become highly publicised and serve to damage the credibility of the entire industry. The recent serious incident involving a spill from a Romanian mine, was blamed for triggering æone of the worst environmental catastrophes in Eastern EuropeÆ. It is important to clearly demonstrate to the general public that these incidents are not representative of the industry as a whole. Where such incidents have occurred, the causes are generally related to poor design and/or construction, inadequate supervision and/or monitoring and maintenance, lack of independent expertise, inadequate risk identification and treatment and no provision to ensure that rehabilitation and long term management of the site occurs. Many people are unaware that these issues have been considered and provided for at the Martha Mine. Despite the fact that the first tailings storage facility has performed very well over fifteen years of operation, the long term safety and security of the tailings storage facilities continues to be questioned and debated by the public. The best way to address this is to provide quality information to enable a better understanding amongst the general public.

Jan 1, 2002

By R Byrnes, P Hensley

The outstanding environmental management initiatives undertaken by Novacoal at its Western Main Site near Lithgow in New South Wales over the past five years are detailed in this paper. These initiatives have been based on a combination of proven and innovative investigation and implementation techniques, close consultation with regulatory authorities and full support by colliery management. The results of these initiatives have enabled the colliery to exceed its pollution control obligations from a base well below industry standards. The initial poor condition of the mine was the result of over 50 years of traditional mining which paid little regard to environmental management. The transformation of the colliery within such a short period, with limited capital, is considered a model for the N.S.W. coal industry.

Jan 1, 1995

By M. Makarchian

Existing buildings sometimes experience excessive settlement under their design loads, or due to increased foundation loading, if a change of building use is required. One of the oldest and widely numerical study has been carried out of a simple idealised problem of an underpinned rigid circular foundation to better understand the behaviour of pile used for underpinning and load transfer mechanism from an existing foundation to the underpinning piles. The finite element method has been used for this analysis, with the soil treated as a two-phase elasto-plastic material. It is found that the effect of the length of the pile becomes more significant as pile length increases. As would be expected, the earlier the pile is installed, the less is the final settlement.

Jan 1, 1996

By G. M. Schwartz

THERE has been considerable controversy regarding the structure and mineral constituents produced when iron ore is sintered. This investigation was undertaken in order to establish the fundamental reactions that take place in the sintering process by determining the nature of the resulting minerals. The writer's immediate interest in the subject arose mainly from the request of E. W. Davis for information based on a microscopic study of sinter submitted by him in May, 1926. In the author's preliminary work, samples of iron-ore sinter were secured from the Minnesota School of Mines Experiment Station and from commercial plants. These were polished by the usual methods for polishing opaque ores. In order to study these surfaces satisfactorily, it is necessary to magnify them rather highly, a range from 100 to 1000 dia. being used. For the higher magnifications oil-immersion lenses and an intense source of light are necessary. After the preliminary study had shown the problems involved, a series of small samples were sintered under carefully controlled conditions and with analyzed materials. Variations in the relative amounts of ore, coal and water were made in order to study the effect of each constituent. The attempt has been to arrive at a clearer understanding of the sintering process and the reactions involved without reference to any preconceived notion as to sinter. It is clear that the study of polished surfaces has yielded results not possible with thin sections alone. The thin sections made in this work were found unsatisfactory at magnification greater than 75, whereas magnifications of 1000 were easily studied with reflected light on carefully polished surfaces. A rather complete statement of observed facts is made so that the reader may form his own conclusions. The writer's interpretations are suggested.

Jan 1, 1929