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By R. A. Matuszak

Throughout the history of power excavating machines, engineers have continuously tried to shape the main drive speed-torque characteristics to provide an optimum performance from each main motion. Selection of prime mover for the various motions has been the subject of many engineering studies and most forms of energy conversion have been tried. A new form of electrical power conversion looms on the horizon' as the most optimum yet. Controlled frequency operation of a squirrel cage induction motor increases the reliability of the most reliable form of energy conversion (electrical) found thus far and at the same time improves the performance characteristics.

Jan 1, 1977

By R. T. Swinderman

"Virtually every article you read on safety has a statement to the effect: “It’s obvious that safety pays”. If it is so obvious, why is it so hard to answer these questions? • How does the Maintenance or Operations Manager convince the Plant Manager to spend money from the annual budget for safety improvements? • How does the Plant Manager influence Corporate to prioritize safety improvements? • How does an engineering firm persuade the owner to spend more on design and equipment up front to reduce risk? There are many cultural and structural reasons why it is so difficult to prove the obvious. In my opinion the main culprits are: the almost universally used ‘Low Bid’ process, variations in reporting incident statistics between industries and countries, and, the Generally Accepted Accounting procedures (GAAP) [or International Financial Reporting Standards (IFRS)]. Conventional wisdom is it’s smart not to spend more than you need to meet the minimum regulations and maximize production. But buying on price alone often harms people, degrades the environment, and reduces the company’s bottom line. How can this be? You met the minimum safety requirements and saved money by buying on price. Don’t those savings go right to the bottom line? When you buy on price you get minimum quality, minimum compliance and are often backed corner with no reasonable options to rectify the problems that arise from buying on price instead of buying on long term life cycle cost. Culturally few companies actually ‘walk the talk’. It is trendy to have giant billboards at plant entrances proclaiming world class compliance with quality and safety standards. Annual reports are embellished with safety slogans and sustainability statements. Behind the front gates and the glossy annual reports the message is clear: produce or be replaced. Only a few companies go beyond the window dressing and actually endorse, from the top down, continuously improving their safety culture. Those that do embrace safety, show significant performance advantages over their competition that are reflected in their safety, productivity and environmental records and, ultimately their financial statements and share price. Current accounting (and reward) systems make it unlikely financial managers will accept non-conventional approaches to justifying expenditures on safety because they are driven to report “hard” numbers that can be documented and are within the “GAAP or IFRS Rules.” But in reality, accountants quantify soft or intangible costs all the time in their financial statements. Justifying safety investments is greatly enhanced by quantifying what most financial managers would call intangible costs. Government agencies have no problem assigning intangible costs to justify regulations to improve safety. How many times have you heard that the regulation is justified because the cost to industry is X while the benefit to the society is 2 or 3X? How can they say that without including intangible costs? We find it hard to believe these government claims of benefits to society because we have been trained to think about saving hard direct costs to justify investments."

Jan 1, 2017

By Danqing Gao, Brijes Mishra

Spatial variance of rock properties is an important characteristic of rock which addresses the heterogeneity of mechanical and physical properties and their effect on underground mining. Assessing spatial variance can be useful for both locating potential difficult grounds and performing reliability analysis in the mining support system. This study shows a microscale numerical model for rock material based on continuum mechanics. To consider the spatial correlation factor of mechanical properties in realistic rock mass, this study introduces a spatial correlation concept into the traditional type III extreme value distribution model. Based on the improved microscale random model, we conducted a series of numerical uniaxial compressive tests and one longwall mine model to investigate the progressive failure of rock. The results show that spatial correlation factor can significantly affect the load-deformation curves and fracture patterns. The spatial variance model was applied to a longwall mine that included several cutting sequences to observe the influence of the spatial variance on roof behavior. The cohesion and friction random fields induced failure that propagated randomly through the immediate roof in different entries. The results showed that the spatial variance provides an accurate prediction of erratic roof falls in coal mines.

Jul 20, 2020

By M Grigorescu, J H. Hodgkinson, H Alehossein

A new framework that collates and interprets pre-existing data to assess vulnerability and ultimately plan to avoid or minimise flood-related risk to infrastructure, people, downtime, environment and revenue has been developed. The æClimate Related Adaptation from Terrain Evaluation ResultsÆ (CRATER) method tested at a coal mine in Queensland, provides semi-quantitative information to assist decision makers when designating investment for minimising vulnerability of mining operations to climate. Here we present the processes involved in this three-step approach that uses pre-existing spatial data of the mine site and local knowledge to build a set of visual tools to assist decision-making. The first step of the process is performing multi-criteria evaluation (MCE) within a geographic information system (GIS) on ranked natural conditions at the mine, such as elevation, slope, drainage, soil and vegetation, which is performed to identify critical flood areas. Secondly, a fault-tree analysis identifies how impact can occur and what options there are for impact reduction. Finally, a resource assessment of the mineÆs capacity to adapt reduces the adaptation options to those most suited to the mine. The results are confidential, but for the purpose of introducing the methodology, we present simplified results, particularly of steps 2 and 3. CRATER can also be used for future æwhat-ifÆ flooding scenarios to identify the most suitable locations for roads, buildings or other critical infrastructure. The methodology is transferable to any mine, series of mines or locations along the mining value chain that have sufficient data, providing a practical decision-making tool to identify æno-regretsÆ actions that not only could reduce downtime after or during an event, but in some cases may enhance production between extreme events. We now plan to test this method at a broader scale, to encompass more than one mine in the analysis.CITATION:Hodgkinson, J H, Grigorescu, M and Alehossein, H, 2013. Climate Related Adaptation from Terrain Evaluation Results (CRATER) - interpretation of pre-existing data for mine site flood vulnerability and management, in Proceedings Water in Mining 2013 , pp 259-266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By D. S. Barr

Mineralogical, lithological, and metallurgical studies were conducted on various gold ore deposits currently controlled by Freeport-McMoRan Gold Company. Ore samples were first lithologically and mineralogically categorized, then subjected to chlorination, roasting, and autoclaving pretreatments to determine their effects on gold recovery in a subsequent alkaline cyanide carbon-in-leach extraction. The studies indicate that, while organic carbon and sulfide sulfur are the primary refractory components, their effect on process response must be interpreted with respect to the deposit's geology and mineralogy. This approach has proven to be an effective method for evaluating metallurgical alternatives and fore-casting future mill performance.

Jan 1, 1987

By CASSANDRA L. HOEBBEL, Jennica L. Bellanca

High-fidelity, immersive training is known for its learning and logistical benefits. While other industries have used virtual reality (VR) for decades, the same uptake has not been seen in mining. NIOSH recently developed an adaptable, scalable VR training platform, VR Mine Rescue Training (VR-MRT), which has attracted significant industry interest. NIOSH is using VR-MRT to understand the barriers to adoption and implementation of VR. As a part of a larger effort to assess the effectiveness and implementation of VR-MRT, researchers have conducted pre-implementation interviews. In this paper, the authors use feedback from individuals at various implementation levels to assess the acceptability and appropriateness of VR-MRT and identify potential implementation barriers for VR more generally. Researchers also describe ongoing efforts to overcome these barriers as NIOSH works to position VR-MRT as a supplemental resource more generally for mine safety training.

Feb 1, 2025

By W. W. Kephart

The glass container industry is the largest producer of glass in the United States. As of this writing, there are approximately 89 active domestic production locations. In 1984, the industry shipped 11.8 million tons of glass containers. Approximately 70% of this production was clear or flint glass, 20% amber, 7% green, and the remainder miscellaneous colors. Although the production of nearly 12 million tons of glass is impressive, anyone following the industry over the last five years is aware that the industry has changed from a pattern of growth in the 1970's to one of maturity in the 1980's. Some observers, less generous, perhaps, have described the 1980's as a period of decline. In 1981, there were 119 production facilities which produced 13.2 million tons of glass the previous year. This equates to a 10% reduction in glass container production from 1980 to 1984, with a corresponding impact on the segment of the industrial minerals producers serving the container glass industry, as shown in Figures 1 and 2.

Jan 1, 1986

By William O. Vanderburg

Tis paper describing the mining practices at the Cold Springs mine of the Wolf Tongue Lining Co. at Nederland, Colo., is one of a series of similar papers prepared by the Fureau of kines on mining practices, methods, and costs at various mines in the United States. The writer acknowledges the assistance of William Leach and William T. Todd, manager and mine superintendent of the Wolf Tongue Mining Co., respectively, in the preparation of this paper.

Dec 1, 1932

By G. S. Hume

FOR MANY YEARS Canada lived in the hope of attaining a substantial production of petroleum and natural gas that, to geologists familiar with the sedimentary basins of this country, seemed an entirely reasonable expectation. There have been surges of exploration activity stimulated by oil and gas discoveries and development such as occurred in Turner Valley. However, it was not until the Leduc field in Alberta was found in 1947, and the significance of that discovery was realized, that the search became really intensive and continuons. Expansion now has become a matter-of-fact attitude based on results which would have been considered impossible of achievement a few years ago.

Jan 1, 1957

By Shinichi Konda, Gary Nishimura

"Thousands of years ago large glaciers carved much of the landscape in Puget Sound, depositing abrasive and granular soils including cobbles and boulders along with layers of clay and sand. Tunneling in this geology – common throughout much of the northern and Midwestern U.S. – is challenging and can be unpredictable. The use of pressurized face tunneling, most commonly with EPBs and slurry type machines, has made excavation in this geology more efficient, but difficulties still remain. Through analysis of recent projects in Seattle, Washington, USA, the authors draw conclusions as to the best TBM designs and operational parameters for this variable, abrasive and often difficult ground. Performance data is analyzed with an eye towards advancements that could further improve TBM tunneling in glacially deposited soils. INTRODUCTION Over the past several ice ages, extensive glaciers reaching across much of North America transported large amounts of soil and rock as they moved across the land. The substantial weight of the ice sheets mixed together a wide range of soil types along with a variety of rocks and boulders of all sizes. Many rock formations were reduced to pebbles or particles containing highly abrasive characteristics. Any boulders able to survive were generally comprised of harder materials which were scattered throughout the soil. This highly variable mixture of abrasive soils and high strength boulders can be found in many areas across the Puget Sound and other regions of the country. Wherever they are encountered, they often create a difficult and unpredictable mining environment for both equipment design and operation. Modern TBMs are optimized early in the design process for specific types of geology, and unexpected conditions can require extensive modifications. In addition, several operational parameters need to be adjusted to balance ground characteristics, and advance rates can be significantly affected in mixed and rapidly changing soil conditions. Both EPB and slurry machines can be used successfully in these conditions, provided their respective operating criteria are met. Ideally, an EPB is operated with a relatively thick muck consistency, which accommodates moderate changes in soil permeability and maintains a reliable pressure differential through the screw conveyor. However, this also causes higher wear on rotating components and requires more energy at the cutterhead. Alternatively, slurry machines typically operate best with a more fluid muck consistency that can be easily pumped through the extensive piping system. This tends to reduce the wear on the cutterhead and the power requirements of the cutterhead drive system, but also makes the machine more sensitive to changing soil conditions. Generally, the slurry piping system is also more capable of controlling high face pressures, although the screw conveyor of an EPB can also be designed to accommodate most high-pressure conditions."

Jan 1, 2016

By K. Muehlenbachs, J. U. Stemler

"Abstract - The Boston deposit is a recently discovered Archean lode-gold deposit located approximately 700 km northeast of Yellowknife, in the southern portion of the Hope Bay volcanic belt. Primary H2O-CO2-NaCl fluid inclusions associated with gold mineralization at Boston are of low salinity (4.6 ± 1.4 eq. wt.% NaCl, n = 182) and contain pure CO2. Homogenization temperatures of liquid-phase inclusions average 270° ± 33°C (n = 141), but some fluid inclusion assemblages contain coexisting liquid- and vapor-phase inclusions that homogenize near critical conditions, suggesting phase separation. In these groups, liquid-phase inclusions homogenized at 299° ± 25°C (n = 24), and vapor-phase inclusions homogenized at 338° ± 28°C (n = 18). These temperatures overlap within error, and a median temperature of ~320°C is taken as representative of trapping conditions within the veins. An approximate pressure of 2-3 kbar was estimated from fluid inclusion isochores at this temperature. Stable isotopic compositions of carbonate minerals from the mineralized zones range from -4.7‰ to -3.1‰ in d13C, and from 11.2‰ to 12.8‰ in d18O; quartz ranges from d18O = 12.8‰ to 14.9‰; and pyrite ranges from d34S = 2.1‰ to 3.5‰. The d18OH2O, d13CCO2, and d34SH2S values of the fluid calculated from these minerals at 320°C are 6‰-9‰, -2.4‰ ± 0.6‰, and 1.5‰ ± 0.5‰, respectively, and are intermediate between metamorphic and magmatic compositions. A unique source for the fluids cannot, therefore, be constrained from these data. Petrographic and geochemical data for the Boston deposit are consistent with data from other Archean lode-gold deposits worldwide, implying that the Boston deposit formed in a similar environment and from similar types of fluids. These results suggest that the Hope Bay volcanic belt may represent a major new mesothermal gold belt in this part of Nunavut. Sommaire - Le gîte Boston a été récemment découvert à environ 700 km au nord-est de Yellowknife dans la partie sud de la ceinture volcanique de Hope Bay, il s’agit d’un gîte d’or filonien d’âge Archéen. Les inclusions fluides primaires de H2O-CO2-NaCl associées à la minéralisation aurifère du gîte Boston présentent une faible salinité (4.6 ± 1.4 eq. pds.% NaCl, n = 182) et contiennent du CO2 pur. La température d’homogénéisation des inclusions à phase liquide est en moyenne de 270° ± 33°C (n = 141), mais certains assemblages d’inclusions contiennent des phases liquides et gazeuses coexistantes qui s’homogénéisent dans des conditions quasi critiques, suggérant qu’elles résultent d’une séparation de phase. Dans ces groupes, les inclusions de phase liquide s’homogénéisent à 299° ± 25°C (n = 24) et les inclusions de phase gazeuse s’homogénéisent à 338° ± 28°C (n = 18). Ces températures se recoupent à l’intérieur des limites de l'erreur de mesure, et nous considérons qu’une température médiane de ~320°C est représentative des conditions de piégeage dans ces veines. Les isochores permettent d’estimer une pression d’environ 2-3 kbar à cette température. La composition des isotopes stables des carbonates dans les zones minéralisées s’étend de -4.7‰ to -3.1‰ pour d13C et pour de 11.2‰ à 12.8‰ pour d18O; les valeurs de d18O pour le quartz varient de 12.8‰ à 14.9; et les valeurs de d34S dans la pyrite vont de 2.1‰ à 3.5‰. Les valeurs de d18OH2O, d13CCO2, et d34SH2S du fluide calculé à partir de ces minéraux à une température de 320°C est de 6-9‰, -2.4‰ ± 0.6‰, et 1.5‰ ± 0.5‰ respectivement, reflétant des conditions intermédiaires entre des compositions métamorphiques et magmatiques. Il n’est donc pas possible d’identifier une source unique pour ces fluides à partir de ces données. Les données pétrographiques et géochimiques du gîte Boston sont similaires à celles d’autres gîtes d’or filoniens ailleurs dans le monde, ce qui implique que le gîte Boston s’est formé dans un environnement similaire à partir des mêmes types de fluides. Ces résultats suggèrent que la ceinture volcanique de Hope"

Jan 1, 2006

By K. Yamaguchi

"This Precious metals content copper scrap is treated with a copper smelting process, and copper and precious metals are recovered. The precious metal lost in the slag is increasing with increasing of treated scrap amount. To determine the portion of the precious metals chemically dissolved and that associated with the mechanically trapped matte in the slag will be a key factor to improve the recovery of those metals. The distribution of precious metals between copper matte and FeOx-SiO2 slag phases is determined at 1300 oC and a fixed partial pressure of SO2 of 0.1 atm for the matte grades from 40 to 70 mass% of copper. The distribution ratios show a tendency to increase when the grade of matte is increased. In addition, the solubility of platinum and rhodium in the FeOx-SiO2-CaO slag under the air and the solubility of platinum in the FeOx-SiO2 slag equilibrated with a pure platinum or the Pt-Cu alloy were determined at 1300oC in the range of oxygen partial pressure from 10-9 to 10-7. The solubility of platinum and rhodium in the slag tends to increase with increasing content of copper in the slag and oxygen partial pressure. INTRODUCTIONThe stringency of the supply and demand of platinum group metal (PGM) intensifies by localization for resources and increase of the demand for PGM, furthermore, smelting and the recycling of PGM in the nonferrous smelting process take an important role. Scrap containing a precious metal for the purpose of collection of PGM is treated by copper smelting recently. With increase of the treatment amounts, loss of PGM in slags is the serious problem.In considering of PGM loss in slags, knowledge of the distribution behavior for PGM between slag and matte phases or slag and copper phases and the PGM solubility in slags is important. The distribution ratios of silver and gold between the FeOx-SiO2 slag and the Fe-Cu matte were reported by Roghani (Roghani et al., 2000), Shinha (Shinha et al., 1985) and Takeda (Takeda et al., 1993) However, there is no data for the PGM distribution ratio. On the other hand, the PGM solubility in slags was reported by Sano (Sano et al., 1997) However, there is very few report for the solubility of PGM in the nonferrous smelting slags."

Jan 1, 2012

By D. W. Alexander

Researchers from the U.S. Office of Mine Safety and Health Research (OMSHR) of the U.S. National Institute for Occupational Safety and Health (NIOSH) completed field trials during coal mine rescue contests using simulated gas detectors in place of placards. The gas monitor simulator (GMS) devices replaced static, paper placards to deliver gas concentration data. Eleven teams were observed during the field contest, which was approved by the Mine Safety and Health Administration (MSHA). GMS devices were given to three team members (the captain and both gasmen). Observation of teams revealed that team members changed behavior by acknowledging and sharing information more often while using the GMS. As a result of this research, it has been demonstrated that under the existing contest format, the newly developed GMS device may be used with no adverse impact on team contest performance. Furthermore, when GMS technology advantages are used, contest realism is improved. In the future, competency assessment may be incorporated.

Jan 1, 2012

By J Cronin

For the last decade, we have read about the great technical innovation that is coming to the mining industry that will increase safety and productivity. There is consensus that it will be a technical innovation that will produce a step change in mining costs and outputs (as opposed to bigger machines or less people); however, this innovation (while freely available) has not taken hold in the industry. While there are a few mines that have embraced technology, the majority of underground mines simply do not have the expertise or technical capability to implement innovation and automation.With unexploited mineral deposits becoming deeper and more remote, and thus more hazardous to mine, telepresence offers the ability to remotely execute production tasks while separating personnel from hazards. As the technologies required to deliver telepresence mature, the potential for there to be no personnel underground during production activities is becoming a reality (the ‘dark factory’). So significant is the capacity of telepresence to mitigate risk, it is proposed that it be included as a separate entry in the hierarchy of hazard mitigation controls.Technical innovation such as the optimised short-term interval control of the production process and the automation of underground mobile fleets offer significant increases in production along with lower operating costs. This paper explores the most critical components for the successful implementation of technology in underground mining; redundant, robust and high-bandwidth communications networks to carry data from distributed networks of smart sensors and to convey teleoperation commands; and high-definition video to provide operators with detailed, real-time data. The days of analogue ‘leaky feeder’ as a base case for communications are over. The human resources required to support the expected wave of innovation are significant and will be difficult to maintain in remote areas as the same skills and expertise are in demand in other industries.The paper highlights barriers to innovation in the mining industry, and a lack of technical and scientific expertise within the industry to be able to identify, implement and manage technologies that can increase safety and productivity. As well, an over-reliance on basic net present value (NPV) financial analysis that is used in the industry punishes investment in technology (capital expenditure; CAPEX) and accepts higher operating expenditure (OPEX) due to the discounting of future savings in operating costs.CITATION:Cronin, J, 2017. Telepresence – the application of remote control and automation technologies for increased safety and productivity, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 213–224 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By K. Bommer

"In today’s fast paced, globally competitive world, reliability and machine uptime are of the utmost importance to a successful operation. Along with these targets more emphasis is being put on cost reduction and decreasing the environmental impact of the overall system. To achieve these goals, automatic lubricators and lubrication systems have been used in many industries for years and are now becoming a common tool in the mining industry as well. These systems are able to provide proper lubrication amounts at the proper times autonomously, helping to keep the machines running smoothly while minimizing the physical support required. Copper mines in the southwest have begun utilizing auto lubrication to avoid mistakes and unplanned shut downs on critical equipment. This paper will describe the engineering behind these products and review case histories where these tools have been successfully utilized in the mining industry. INTRODUCTION In a dirty, dusty, wet environment, where machine uptime is imperative, proper lubrication of bearings is the only way to survive. With the push for cost reduction and mines striving to lower their environmental impact and increase worker safety according to MSHA guidelines, the old lubrication practices have come under scrutiny. It is no longer encouraged or cost effective to have maintenance personal walk from point to point throughout the entire mine pumping a shot of grease into each bearing once per shift. Automatic lubricators and lubrication systems have been on the market for years but recently, as the market focus has changed and technology has developed, the use of these systems has begun to rise in the mining industry. Automatic lubrication systems can be as simple as a single point lubricator lubricating one (1) bearing or a more complex system lubricating numerous bearings. With system design, the automatic lubricator provides a preset amount of grease to a bearing at regular, predetermined intervals. The systems designed to lubricate more than one bearing contain grease pumps of some design and possibly PLC controllers which can be used to remotely adjust and monitor the system. As can be seen in Figure 1, the right amount of lubrication can be achieved much more reliably with automatic lubricators. Depending on application needs, the market now has products to fit almost every wish list. This paper is going to focus on the single point systems that are lower in cost but are still being effective."

Jan 1, 2015

By W. D. Monaghan

One of the major ignition sources of fires and explosions in underground U.S. coal mines is flame cutting and welding. On May 20, 2006, a flame-cutting operation at the Darby Mine No. 1 led to an explosion that resulted in five fatalities. On Jan. 22, 2003, another explosion caused by flame cutting at the McElroy Mine resulted in three fatalities and three serious injuries. On June 22, 1999, a flame-cutting and welding operation at the Loveridge Mine caused a fire that required sealing the mine for an extended period. On March 19, 1992, an explosion initiated by welding at the Blacksville No. 1 Mine resulted in four fatalities. These examples of mine incidents demonstrate the need to conduct research to develop best practices for safely conducting flame cutting and welding in underground coal mines. The National Institute for Occupational Safety and Health (NIOSH) conducted a study on fires and explosions in underground U.S. coal mines that were caused by flame-cutting and welding operations to determine the root causes of these types of incidents. The methodology included interviewing mining personnel who perform flame-cutting or welding operations in underground U.S. coal mines and visiting mines to observe these operations. In addition, MSHA reports of investigations and accidents statistics were analyzed. The findings were used to identify and compare differences between flame-cutting and welding practices and techniques in small and large mines, eastern and western mines, low-seam and high-seam mines, room-and-pillar and longwall mines, and between experienced miners and new miners. As a result of this study, best practices were developed to reduce the number of ?res and explosions caused by flame cutting and welding. This paper provides a summary of this research.

Jun 1, 2010

By D Giles, A C. Bailey

In the first 20 years of the 21st century, just over 20 per cent of Australian mineral exploration expenditure was dedicated to iron ore, totalling >A$8 billion and >30 million metres of drilling (Australian Bureau of Statistics, 2021). Improvements in the cost, efficiency, safety, reliability and data quality of drilling have the potential to deliver significant productivity improvements, increasing the probability of discovery and reducing the time from discovery to mining. Currently in its third year of research, Mineral Exploration Cooperative Research Centre (MinEx CRC) is focused on a new set of exploration tools and new ways to deploy those tools which recognise the fundamental importance of collecting quantity and quality data from the subsurface, to enable exploration success for all minerals, including iron ore. MinEx CRC is focused on developing more productive, safer and environmentally friendly drilling methods to discover and drill-out deposits. This includes pioneering work on Coil Tube (CT) drilling technology and innovations in Diamond and Reverse Circulation (RC) drilling techniques aimed at improved drilling optimisation and automation. In parallel, MinEx is developing new technologies for collecting data whilst drilling. This is being undertaken in four separate industry-led projects utilising geophysical, seismic, downhole analytical and 3-dimensional (3D) modelling improvements. A National Drilling Initiative (NDI) is also underway, with two drilling programs completed in 2020. The NDI is a world-first collaboration of Geological Surveys, researchers and industry, which undertakes drilling in under-explored areas of potential mineral wealth in Australia and provides a test-bed for new mineral exploration technologies.

Nov 8, 2021

By F. M. Isik

Due to not to being our own sources, some energy sources such as oil and natural gas which are used frequently, are not reliable energy sources for our country. Coal is an important energy source that Turkey also has a certain reserve as many countries have. To be able to use for many years the reserves of this source that comes from fossils, there is a great need to make more investigation and development activities on it. On behalf of using more productively the current sources, briquetting facility is represented that commenced production in The Aegean Lignite Establishment in 2005 which is in Manisa, Soma. This facility is a part of General Directorate of Turkish Coal. This facility is run by Soma Coal Establishment that works in return for royalty in a licensed field that belongs to TKI. As the demand of market for 0.5 mm dust coal diminishes, we had to accumulate and stock unmerchantable dust coal. Besides, we have intermixed 0.5- 1 mm powder coal and 0.1 ? 0.5 mm fine powder coal obtained as a result of washing in coal washer with thermic coal with low price as we could not find a client in the market. In this study, the production stages of briquette coal with high quality produced as a result of pressing by mixing 0.5- 1 mm powder coal and 0.1 ? 0.5 mm fine powder coal with molasse and lime, quality control, and data?s obtained about calories and solidity of products were presented. By briquetting of 0.5- 1 mm powder coal and 0.1 ? 0.5 mm fine powder coal washed in coal washer, it became possible to sell these coals on a high unit price and by providing the demand of coal of the market, we contributed to productivity of our firm. Keywords: briquette coal, briquetting, producing stage

Sep 1, 2012

By J. W. Sanger

The establishment of a central steam-heating system in Winnipeg and its inauguration in October, 1924, has attracted a considerable amount of attention. Not only does it excite the curiosity of the engineer, but it has stirred financial and civic bodies throughout Canada to such a degree that there is now a much keener general interest in this particular type of public utility than has been shown heretofore. This does not mean that we may expect a mushroom growth of central-heating systems in all our larger Canadian cities in the near future, but it does mean that the pioneer work which Winnipeg is now doing will undoubtedly be used to guide others in their judgment as to the feasibility of similar projects elsewhere. The success of the municipal hydro-electric system in Winnipeg, and the low rates for electricity resulting therefrom, was without a doubt the most important factor influencing the citizens of Winnipeg to venture into this new field. The events which led up to the central steam-heating proposal in Winnipeg are interesting.

Jan 1, 1926

By Cary Hirner, Sarah Lothman, Chris Mueller, Savita Schlesinger, Mike Hanna, Ian Fitz-James

Loudoun Water is currently implementing a quarry to reservoir conversion that will improve water supply reliability in periods of drought and flexibility in water supply operations when turbidity in its Potomac River supplies are high. The Milestone Reservoir Project consists of an inter-tie to the existing Potomac River Pipeline; new pipeline and tunnel; and a pumped intake and outlet works. Planned construction involves significant risks due to underground conditions which includes hard, igneous rock and high groundwater at the creek crossing. In addition, the site is constrained by Goose Creek, an adjacent residence, active mining in a quarry next to the new reservoir, public use of adjacent park space, and the Washington and Old Dominion Trail. Working with these constraints will require close coordination with active mining operations and public and private property owners. Safety of personnel involved with construction also represents a concern with quarry high walls over 30 meters in height near the planned construction. In consideration of key projects risks, Loudoun Water determined that an innovative CMAR delivery approach provided the best opportunity to achieve its goals in quality, innovation, front-end cost and schedule certainty, and operational flexibility and reliability. What matters most to Loudoun Water is the value in having a builder participate in the design process where key decisions can be made based on consideration of risks, cost, schedule, quality, and operability and maintainability of the system. While a progressive design-build delivery model may have produced similar outcomes, Loudoun Water had already invested in substantial development of the design for the work, and ultimately, CMAR provided Loudoun Water the opportunity to retain the partnership with the design team while gaining valuable input from a contractor. Among the challenges with CMAR in the Commonwealth of Virginia is a substantial limitation on self-performance corresponding to 10 percent of the construction value of the work. A significant industry outreach program was initiated by Loudoun Water to encourage participation with incentives in contract terms that allowed for the CMAR Contractor to make a reasonable profit. This paper reviews the CMAR procurement process and discusses contract incentives that were adopted to promote the work within the constraints of contract law in Virginia.

Jun 13, 2021