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Purpose of TSUG Continuous Improvement in Mining Share Best Practises Exchange Ideas Network for Frontline Supervisors and Middle Management Meetings ? Two per Year -Spring and Fall ? Thirty Five to Forty Attendees ? Rotate Between Host Properties ? Host Mine Provides ? Meeting Room for One Day Tour of Mine and Maintenance facilities on Second Day

May 1, 2010

By Y. Lizotte

The purpose of this paper is to describe a stochastic simulation program used to assess several dispatching rules applicable to small scale computerized systems for optimizing truck/shovel productivity. The system studied is semi-automated with a dispatcher communicating instructions by two-way radio. The simulation program is structured on an advance clock approach which enables the insertion of dispatching rules at various points in the haulage net- work. The rules tested include minimize shovel idle time, maximizing immediate truck use and assigning trucks to shovels to meet specific production objectives. A variation of the traditional "Match Factor" is implemented to maintain fleet balance throughout the shift. A mine case study demonstrates how the dispatching rules increase productivity of such semi-automated dispatching systems. Practical problems involved in the implementation of small computerized dispatching systems are also discussed.

Jan 1, 1986

By G J. Halstead, R C. Steinhaus

The True Pipe® in-line sampler was developed in an attempt to address the need for a mechanically reliable and correctly designed sampler to suit one-dimensional pressurised slurry pipelines, often found in metallurgical process plants but for which no reliable and representative sampling solution as yet exists.The design, whose operation is based on the principle of symmetry, is described by Dominique François-Bongarçon (2005) with the synchronous opening and closing of relevant valves. It representatively isolates portions of the particulate material stream at predetermined intervals for effective extraction of primary increments for subsequent sample compositing.Theory of Sampling applicable solutions have proven elusive in flowing pressurised particulate material streams, with various attempts to date not having formulated a viable, mechanically reliable and acceptable design.Compliance to sampling theory is critical, and a number of tests were conducted where certain operating parameters were altered to determine their influence and sensitivity on sampling representativeness.The results of the initial series of tests performed on a carefully designed rig are presented, with additional work discussed for necessary investigation in the near future.Getting closer to a robust, economic and correct design for this challenging application in the minerals industry may now not be that far away. Plant management staff will see improved metallurgical mineral balances around their process plants and significantly reduced sampling discrepancies, particularly in tailings applications. Improved quality control is now possible where, due to plant head room constraints, classical cross stream sampling methods cannot be employed.CITATION:Steinhaus, R C and Halstead, G J, 2014. True pipe sampler – a correct design utilising the principle of symmetry in pressurised slurry particulate streams, in Proceedings Sampling 2014 , pp 127–134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

"Standing 92 stories high and just over 1,362 ft tall, Chicago’s Trump International Hotel and Tower is perfectly positioned at the center of one of the world’s most impressive skylines.The Tower serves as a link between its famous predecessors, Willis Tower (formerly, the Sears Tower) to the south and the John Hancock Building to the north. Originally planned to be the world’s tallest building, the project was scaled back when the developers started questioning the need for super-tall buildings after the September 11, 2001 terrorist attacks. In its River North neighborhood, Trump Tower dominates the skyline as a symbol of Chicago’s last great building boom, standing triumphantly over other high-profile projects that have been postponed due to current economic realities.It is often said that the three most important factors in real estate are location, location and location. This maxim was not forgotten by The Trump Organization when the site was selected for the International Hotel and Tower. Located two blocks west of Michigan Avenue and Chicago’s famed Magnificent Mile, the site is bound by the historic Wrigley Building to the east, Wabash Avenue to the north and west, and the Chicago River to the south. The building’s position along a bend in the Chicago River allows visitors and residents unobstructed views to the mouth of the Chicago River and Lake Michigan. Site ChallengesUnderneath the site there are approximately 10 to 20 ft of sand and urban fill underlain by soft Chicago blue clay. At 75 ft in depth, the soft clay transitions into Chicago hardpan, a very hard till that was consolidated by the glaciers over 10,000 years ago. Below the hardpan, the till turns granular with cobbles, boulders and water under pressure. Bedrock is about 100 ft below existing grade and has a weathered surface with fractures and clay seams. Unweathered limestone bedrock is sound and hard with unconfined compressive strengths of 10,000 to 20,000 psi."

Jan 1, 2009

In the future to excavate sufficient coal for power generation, two dredgers would be required to dig overburden or interseam 70010 of the time and three dredgers 40010 of the time. One overburden system was not adequate for this requirement, making coal production reliability vulnerable. TS5 spreader is the new machine element of this system. The selection of the best type of machine configuration to suit the application was then subject to an internal SECV VE Study, a registration of interest and a tender for two machine alternatives. This paper outlines the reasons why SECV planned the Secondary Overburden System and how the Krupp machine met these requirements. It also identifies the main design features of the machine and its constructability which will allow the machine to be operational by the end of May, 1990.

Jan 1, 1989

By Amir Zavichi

Today, with the necessity of timely, on-budget and high quality completion of projects, proper use of construction equipment is essential to ensure project success. Construction equipment places a large monetary burden on the project and if not utilized efficiently, it can result in economic losses. Cranes are one of the most important and expensive operational devices on construction sites. They play a central role, and often activities that rely on crane services fall on the project?s critical path. Currently, material-handling scheduling is done by the crane operator or by an on-duty superintendent using his/hers personal judgment, making the process manual and timeconsuming. Thus, developing an optimal schedule, which considers different dynamic constraints in construction job site, may not be possible based on the current practice. This leads to longer operation times and a negative impact on project cost. This paper presents the latest results of an ongoing study, which aims to design and implement a nearreal time crane operation decision support system to be utilized directly by the crane operator or as an aid for the superintendent in scheduling optimal operation services. This system has several advantages such as maximizing the efficiency of crane operations, guaranteeing the best operation possible to reduce the crane?s travel time, reducing crews and equipment idle time, and minimizing the dependence on subjective human judgments.

Aug 1, 2013

By M Tsai

Tube bundle gas monitoring systems have been used in the mining industry for over 50 years. The initial design was based on four individual gas analysers along with a series of solenoid valves, gas sample conditioning and flow control mechanisms to ensure the correct gas flow stream volume to the analyser. Simtars staff have identified flow control issues when providing operational support to coalmines on numerous occasions. The accuracy of the oxygen analysis is dependent on control of the gas flow to the analyser. Oxygen is one of the parameters used in calculating Graham’s ratio which is used for the detection of spontaneous combustion activity in coalmines. This paper will provide data which identifies the flow control issues by comparing mine site records for the two surface sample lines in the analyser room and the gas cage. Mine sites will be deidentified within the paper. The paper will discuss some of the changes that have been made in modern tube bundle systems and compare the change to the initial design specification developed by the UK National Coal Board, investigate possible operational impacts and provide a technical fix to solve the current flow issues being experienced at some mines.

Oct 12, 2022

"HISTORY Tube bundle systems have been used in the coal mining industry for gas detection since the 1960’s. At the time there were developments were underway for improved gas monitoring systems. The primary gas detection systems in use were the flame safety lamp, colorimetric stain tubes and the taking of samples for analysis by gas chromatography. The MSA D6 hand held methanometer was approved in the UK for statutory methane measurements in 1972 and became very popular due to its smallness and simplicity of use. In 1973 Sieger Limited also developed a BM1 methanometer which could be installed underground and relay methane concentrations to the surface. Similar developments were underway for carbon monoxide detection and one was developed in 1982 by the Yorkshire Regional Laboratory of the NCB commercial development was undertaken by Sieger Limited who named it the ‘SCO1’. The UNOR 1 carbon monoxide and methane analyzers were approved for underground use in the United Kingdom in the late 1960’s.5 The technique was developed by Dr Luft of Bergbau-Forschung Essen and the equipment was manufactured by Maihak in Germany. The apparatus was flame proof and provided an intrinsically safe output which allowed the result to be telemetered to the surface through colliery communication systems. Both analyzers work on the same principal and each of the gases adsorb a certain wavelengths of infrared radiation. The detector measures the residual transmitted radiation and determines the percentage of gas present in the sample. These flameproof versions had proven to be robust and reliable. The UNOR 1 had been used in the Saar region of Germany and Scotland in the UK. The development of tube bundles for hydraulic controls enabled the development of the tube bundle gas monitoring systems we know today. A bundle of tubes are taken underground through a shaft, a borehole or drift then distributed to the required monitoring points. This enabled the ongoing monitoring of the underground environment when the power was isolated at 1.25% CH4. In 1972 the United Kingdom (UK) National Coal Board (NCB) produced a hand book for tube bundle systems which was subsequently updated in 1974. This is a useful guideline into the operational aspects of tube bundles systems at coal mines6. Many of the processes identified are being followed today. The United State Bureau of Mines (USBM) prepared a circular similar to the NCB handbook on tube bundle systems.7 The circular was prepared by Litton C and it was targeted at the design criteria for tube bundle the systems. The circular also states that “pneumatic monitoring systems can be used to monitor for hazards that develop quite quickly”."

Jan 1, 2016

By Alexander Smith

"The three principal known mineral deposits of the Taku River area lie in the Tulsequah synclinorium. The axis of this north-south trending structure is along Tulsequah River valley; about 6 miles east of the eastern contact of the Coast Range batholith.The one proven mine of the area, the Polaris-Taku, is on the west side of the valley. It is a gold property, the gold occurring in fine needles of arsenopyrite disseminated in carbonatized volcanics. The mine was originally called the Whitewater, and the adjacent area the Whitewater gold belt. During the years 1937 to 1942 gold having a value of $3,284,000 was produced from 313,500 tons of ore milled."

Jan 1, 1954

By Márcia Maria da Silva Monteiro Pereira

Tundish is the last reactor where significant metallurgical operations can still be done. Calcium aluminate slags are able to positively contribute to metallurgy considering oxide separation, protection against reoxidation and preclusion of resulphurisation. However, these are poor insulators. When using low melting point slags it is necessary to use another covering material. The deviation from saturation can be used as a measure of absorption capacity. By utilizing computerized construction of ternary and quaternary diagrams it is possible to compare different slags and to find proper slag compositions with reasonable capacity to dissolve inclusions. Objective of the present technical contribution is to evaluate tundish slag capacity to absorb inclusions, considering a particular tundish industrial slag and the changes in its chemical composition during continuous casting of steel. It was observed that slag composition changed during the continuous casting process; this variation is possibly related to interaction between the CaO-Al2O3 liquid slag and the rice hull ash layer which is used above it. Computational thermodynamics was used to determine activity of alumina dissolved in liquid slag; it was observed that the variation in slag composition did not change slag capacity to absorb inclusions, since precipitation of Al2O3 solid phases is not predicted.

Aug 17, 2017

By P. W. Billwiller

Abstract The Britannia Mining and Smelting Company, Limited, have replaced diamond drills with percussion drills and tungsten: carbide bits for most of their blast hole drilling operations and have thereby reduced ore breaking costs. Two-inch Carset bits .are used, with one-inch hexagonal Atlas Chippewa alloy steel in 3-foot .and 6-foot lengths. Locally made couplings of Atlas SPS 245 alloy steel connect the rods. The machines used are 31½-inch automatic leyners with lugged or anvil block chucks. For drilling holes below the horizontal, the lugged machines with special adapter rods made from 114- inch solid round Atlas SPS 245 are required. These rods are lugged at one end and a water hole is drilled for six inches into the other end. Over this rod is placed a water swivel which permits the water or air to be sent directly into the steel. A decreased cost per foot, increased footage per shift, and the use of standard equipment and crews are some of the main advantages of tungsten carbide drilling over diamond drilling. Introduction Long-hole drilling with percussion drills and sectional steel was introduced in several American mines some twenty-five years ago. It did not prove very successful, however, because the rapid gauge loss in steel bits necessitated the use of very large starter bits. This in turn rapidly fatigued the straight carbon-steel then in use, made it difficult to maintain the couplings, and resulted in a slow drilling rate. The introduction of the tungsten carbide insert bit and alloy drill still has changed this picture and opened real possibilities for the application of percussion drills to blast-hole drilling. If this type of bit had been perfected ten years ago, much of the research work and experimenting done to apply diamond drills to ore breaking would have gone toward developing the application of the tungsten carbide bit to this problem.

Jan 1, 1950

By J. W. Reynolds

Introduction The Sullivan mine, at Kimberley, B.C., is the principal source of ore for the Consolidated Mining and Smelting Company of Canada, Limited. Current production amounts to about 2,500,000 tons of lead-zinc ore a year. With approximately 1,600,000 feet of percussion drilling and 700,000 feet of diamond drilling being carried on each year, any improvements in drilling practice are important. Testing of new equipment and drill bits is a major function of the Testing Department at the mine. Tungsten carbide bits have been the subject of many tests since 1947 and have been used in operations since 1948. This paper details with the methods of testing and gives comparative data on performance and costs for tungsten carbide bits as compared to steel bits. Operational use of tungsten carbide bits started in April, 1948, and the extent of application has increased considerably since that time. The scale of employment is illustrated in Table I, which also shows other statistics on the use of carbide bits. Up to the present time eighteen types of carbide bits or tipped steel, as made by six different manufacturers, have been tested. In general, one supplier's bits have been used in operations, but some large-scale operational tests have been carried out with other types. The types tried are shown in Table II. To date they have been, the subject of 33 tests, covering the destruction of 804 bits over an observed footage of 42,586 feet.

Jan 1, 1951

By J. C. Heaslip

Introduction The greatest single advance in rock drilling practice since the advent of percussion drills was the introduction of tungsten carbide tipped rock drill?bits. The evolution of rock drills has been a long and highly diversified effort which has culminated in the highly refined ?drilling machines we know today, but because of the spectacular possibilities shown by ?detachable bits, and especially those with tungsten carbide inserts, there is little doubt that the cutting face of .the drilling unit has in recent days stolen the spotlight of rock drilling research and commanded the major attention of the rock drilling fraternity. "Solid" Steels Until about twenty years ago, all rock was drilled with a one-piece rod with a bit forged on one end. In the early years of the art of rock drilling, there was tried every conceivable pattern of :bit from the single-edge chisel to elaborate geometric 'designs. In the end, it was found that a 4-point bit with two sharpened cutting edges crossing each other at right angles would serve best for most rock drilling requirements. For some years thereafter, the main concern of drill manufacturers was .to obtain the best possible steel for drill rods. This was not accomplished as easily as might be thought. The cutting end had to be such that it could be hardened sufficiently to do its work without premature dulling and yet not so brittle as to shatter under the multiple impacts.

Jan 1, 1951

By P. B. Altringer

The Bureau of Mines conducted laboratory tests to develop a process for recovering a marketable grade of tungsten from the brine of Searles Lake, Calif. The brine contains only 56 parts per million of tungsten (70 ppm WO3). Using ion exchange resins synthesized by Bureau chemists, 98 percent of the tungsten was extracted from the brine and 92 percent of the tungsten vas recovered as a marketable iron-tungsten concentrate containing 44 percent tungsten as tungsten trioxide. Although major technical problems have largely been resolved, research is progressing to escalate testing in a process investigation unit to provide more reliable data for an economic appraisal.

Jan 1, 1978

By M. Jackman

"Froth stability is critically important for an effective separation of fine and ultrafine particles using column flotation. While a desirable froth stability is required to facilitate the drainage of entrained gangue particles for secondary cleaning, excessively stable froths could create problems in separation efficiency and down-stream processing. In this work, we demonstrate that a stable foam was produced using a poly (N-isopropylacrylamide) (PNIPAM) solution at the temperatures below the critical solution temperature. In contrast, very little foam was produced at the temperature above the critical solution temperature (~32 oC) of PNIPAM. We can also tune the foam stability by changing the temperature of wash water. When warm water of temperature of 50 oC was applied, the foam collapsed and diminished. This is probably attributed to the switching of PNIPAM molecules from coiled to a globule conformation as the temperature is increased. Our results indicate that the foamability and foam stability can be tuned by tempartureresponsive PNIPAM. This is the first time that thermo-responsive PNIPAM has been shown to have potential as a modifier of froth stability in column flotation.INTRODUCTIONIn mineral processing, column flotation has become a more prevalent process in the separation of fine mineral particles (typically < 100µm). Traditional flotation cells are sometimes less efficient in selective separation of ultra-fine particles (Kohmuench et al., 2009). The efficiency of flotation columns is dependent on the froth stability at the top of the cell to drain the unwanted gangue particles entrained in the froth. The greater froth height in flotation columns, compared to mechanical flotation cells, gives a longer froth residence time, allowing more of the drainage process to take place before the froth reports to the launderer. Secondary cleaning, by applying a wash water shower to the froth, enhances drainage of gangue particles entrained in the froth, and improves the recovery of the targeted minerals (Finch et al., 2007).While a stable froth is desirable to facilitate drainage of entrained gangue particles, greater amounts of fine particles have been found to contribute to excessively stable froths which could create problems for down-stream processes (Bethell et al., 2012). Operators have tried spraying additional wash water on the froth, and reducing frother dosage to destabilize the froth and to prevent backup at the launderer. The former is sometimes inefficient, and the latter results in unacceptable recovery loss. Currently, the best practice is often the installation of larger froth launderers, adding expensive defoaming agents, and/or using deaeration tanks (Bethell & Luttrell, 2005)."

Jan 1, 2016

By Marco Sonnenschein

Belt conveyors for tunnelling are industry standard and key to high performance of TBM drives. Conveyors reduce traffic in the tunnel and increase safety in the tunnelling process. This paper will illustrate the state of the art of tunnel belt applications in very long and curvy tunnels like the Coxwell Bypass Tunnel Project in Toronto, Canada.

Jun 23, 2024

By Clayr Alexander

Stillwater Mining Co. (SMC) is engaged in developing, extracting, processing and refining palladium, platinum and associated metals (PGM)from the J-M Reef. This geological formation is located in Stillwater, Sweet Grass and Park counties in southern Montana. Associated byproduct metals include rhodium, gold, silver, nickel and copper. SMC’s current mining operations are near Nye, MT. The company is currently developing a second underground palladium and platinum mine, the East Boulder project, about 21 km (13 miles) west of the Nye operations. A 5,650-m (18,550-ft) tunnel is required to gain access to the ore-bearing horizon (J-M Reef).

Jan 1, 1999

By D Willis, A Shanahan, C Jacobs, T Luxner

The application of tunnel boring machines (TBM) for reef mining is a unique practice with benefits over current mining methods given the right geology and geometry of the orebody. The Stillwater Mining Company (SMC) of Nye, Montana, USA operates two mines for obtaining platinum metals. The operation is currently using a 5.5 m diameter open-type machine for further mine development, as well as another TBM that they own.The latest 7.1 km bored tunnel, known as the Blitz Tunnel, will be routed parallel to the ore deposit in igneous mafic intrusive rock, and will be used for the life of the mine operation. It will be used to map the ore deposit, and provide a rail haulage route.Detecting the reef in relation to the TBM requires careful analysis. Diamond core drilling occurs ahead, above, and alongside the machine at every 150 m. The core is drilled, logged, and interpreted on the spot, concurrent with boring. Based on the data, the TBM is readjusted so that it stays on the correct bore path.This paper will highlight the application and benefits of TBM usage for reef mining, with detailed descriptions from the mine site.CITATION:Willis, D, Jacobs, C, Luxner, T and Shanahan, A, 2014. Tunnel boring machine usage speeds up development at Stillwater Mine, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 683–690 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By M Rauer

With a worldwide growing population the demand for higher living standards, food and the development of new technology is rapidly rising. To allow for a continuous growth, larger quantities of minerals and raw materials are needed at a faster pace. Different methods have been developed to access or tap ore more quickly, such as improved drill and blast operations, mechanical mining methods using equipment such as roadheaders (RH), longwall miners and other technical equipment. Another possibility to access and develop mines faster is the use of a tunnel boring machine (TBM).The historical usage of TBMs is surprisingly long, but the opportunity for technology adoption by the majority of worldwide mining companies remains largely untapped. Dozens of full face TBMs have been used by mines around the world, including two that will begin operation soon in Australia. TBMs have been used to safely and rapidly gain access to the orebody, or to expand access to the orebody to increase output by running a TBM along the edge of the orebody for several kilometres. These machines have also been used for ventilation and for conveyor tunnels for ore removal. They have been used to quickly excavate long and winding declines giving access to an orebody at several levels in a short period of time.Tunnel boring technology can be used for mine declines, mine access tunnels and all sorts of different mine designs and set-ups. TBM technology simply needs to be adapted to the mine conditions and, if manufacturers are involved early on in the planning process for mine development, the operation can be very successful. In some cases, historically typical mine designs may need to be re-thought.One mine, the Stillwater Platinum mine in Nye, Montana, is currently employing its fourth TBM in 25 years. Two were used to create tunnels running alongside the orebody, rapidly expanding access to the orebody in many locations for increased output. Two were used to create parallel access tunnels to a mine expansion at the East Boulder orebody; one tunnel is for conveyor haulage and the other for vehicular access. TBMs have been employed successfully many times to rapidly drive vehicular decline tunnels to multiple mine levels, such as at the San Manuel – Magma Copper mine in the USA. While TBM technology may not seem to be optimal for every mine, these success stories show that the method can provide vast benefits for the right projects.Early use of TBMs in extremely hard rock metal mines, in the 1960s and 1970s, had limited success since performance was low. However there have been great improvements made over the years in the strength of rock which can be excavated by TBMs with high performance. Other important improvements involve the provision of a safe work environment, safely and rapidly supporting the rock and predicting geology ahead of the TBM.This paper will briefly note the more than 20 TBM mining projects and highlight some notable successes. It will then go on to give a status report on the two active TBM mining projects in Australia and the difference between a TBM operation versus other excavation methods such as drill and blast (D&amp;B) or RH excavation.CITATION:Rauer, M, 2014. Tunnel boring machines in mines – a?brief review of past use with a status report on use today in Australia, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 663–670 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Ali Hafiz, Aidin Golrokh, Tom Iseley, Kaz Tabrizi, Saleh Behbahani

In the USA many highway tunnels were built during the 1930s through 1960s. This indicates that these tunnels have exceeded their intended design service life. Based on the initial tunnel inventory conducted jointly by the Federal Highway Administration (FHWA) and the Federal Transit Administration (FTA), more than 526 highway tunnels have been identified in the USA. For understanding the condition of the tunnels and risks associated with deteriorating conditions, comprehensive condition assessments are necessary to mitigate risk and remediate works as required. Monitoring the condition and rate of deterioration of tunnels is vital for timely tunnel maintenance and rehabilitation to avoid sudden tunnel collapse. This session will explain the necessary steps for tunnel inspection and review some of the state of the practice information on tunnel inspection techniques.

Jun 13, 2023