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By O. Lashkari

Manipulation of pouring temperature is an efficient way to produce different microstructural features. In order to characterize the microstructure of rheocast billets due to different superheats of 615-695 °C, the parallel plate compression method was employed. Foundry 356 Al-Si alloy with different morphologies of primary a-Al particles were tested at different initial pressures of 4,8, 11,2 KPa, The resulted strain-time graphs were further treated mathematically to calculate viscosity of SSM billets. The interrelationships of viscosity, the microstructure and primary phase flow during compression are discussed, It is shown that the dendritic primary a-Al structure has the highest viscosity number which is almost three orders of magnitude greater than those for globular morphology, The current research have, for the first time, shown the validity and reliability of "parallel plate compression viscometry" method in characterizing microstructural evolution of Rheocast SSM billets.

Jan 1, 2005

By R. Lepsoe

THE basic products of the Company are lead and zinc. Around 950 tons of these metals are produced each day. In the last decade, the production of by-products has increased to such an extent that they are now nearly as large an operation as that of the base-metals. Of the many by-products, the most objectionable, and up to a few years ago the most useless, was the sulphur. The sulphur comes in the ore from the Sullivan mine. It is in the ore chiefly as lead, zinc, and iron sulphide. By selective flotation, these three sulphides are separated into the lead concentrates, the zinc concentrates, and the mill tailings. These mill tailings contain the bulk of the iron and the sulphur. Of the 6,5CO tons of ore treated per day, about 5,000 tons are wasted to the mill tailings dump, and, while now valueless, will in future years undoubtedly be used as a source of iron and sulphur. There are about 1,500 tons of sulphur and 2,200 tons of iron per day in the tailings, and about 400 tons of sulphur left in the total concentrates. In the recovery of lead and zinc in the pure form, the first step is the roasting operation. Here, most of the sulphur is driven off as sulphur dioxide in the gases. It has always been apparent that this sulphur should be. recovered and utilized if possible. At the same time, this would cure the smoke nuisance. Because, in spite of the low concentration of sulphur dioxide and the fact that it was discharged from stacks at an elevation of 400 feet above the plant, some damage to vegetation close to the plant had been experienced.

Jan 1, 1937

By Iwueze Anaekperechi Rose

The International Labor Organization has declared mandatory adequate provision of safe workplace and safety for all workers in all occupations including the mining sector. Early scientists like Agricola (1559) who studied the health of Miners, found that there are peculiar health problems associated to their work and working environment. This unsafe working condition was one of the major factors that resulted to the Industrial revolution in England and eventually led to the establishment of regulations and laws guiding operations in all workplaces and workers in England and all over the world. Recent studies by Heinrich suggested chains of events of safety issues in the mining sector. Occupational injuries, accidents and ill health have huge social and economic implications on workers, their families and communities. Top mining top issues are respiratory diseases, noise, explosives, ventilation, fire, and explosion. However, one of the principal mechanisms for achieving Occupational Health and Safety (OHS) goals and mapping the future is government regulations of employers. In Nigeria, the situation is not different; mining operations are equally hazardous and have far reaching implications. In 1995 the Ministry for Solid Minerals was established to focus on the development of other categories of mineral products ranging from gold, coal, uranium, and tantalum deposited across the country. Prior to this an Act of Parliament Act Cap 121 of 1946, was in place to regulate amongst other contents mining safety. This was subsequently reviewed following the incidence of Lead poisoning resulting from small scale miners processing gold ore highly contaminated with lead in Zamfara state (northern Nigeria). Hundreds of children died as a result of exposure to lead poisoning, it was clear that the regulations were not sufficient (details to be discussed). However, advances have been achieved in mining engineering since then. A review team was constituted to provide a more stringent law to regulate mining operations in Nigeria. The strategies for mapping the future of OHS in mining engineering will employ amongst others setting and adopting ISO/ILO standards and enforcement; providing technical assistance; and establishing sustainable developmental structures as surveillance and compensation. The management systems approach was also developed as a result of cases of accidents. The accepted international standards guidelines and requirements will be proposed. Furthermore in mapping the future for Mining Engineering, it is suggested that most countries have their own management strategies and legislation to improve safety of workers through greater consistency and efficiency of OHS programs. Some American researchers came up with the Safety Engineering Model. The Australian Mining Council of mineral and petroleum resources after the Catastrophic Maura Disaster developed the National Mine and Safety Framework. In Canada, after the Hillcrest mine disaster in 1914, Allan shaft coal mine catastrophe in 1918, Westray mine explosion in 1992 and other disasters, Occupational Health and Safety Act R.R.O 1990 was sufficiently developed to provide adequate safety conditions and standards. In Nigeria after the disastrous Zamfara lead poisoning, which claimed the lives of hundreds of children due to exposure and lack of appropriate safety measures, stringent measures were developed by the federal ministry of Justice to address and regulate mining process in Nigeria.

Aug 1, 2013

By Clifford S. Gibson

A year ago a paper (1) was presented at the Annual Western Meeting of the Institute regarding silicosis in Ontario mines. It described the whole problem as we see it and discussed the means of prevention. The work and aims of the Technical Silicosis Research Committee of the Ontario Mining Association, and of the Committee's field engineer, were fully described also and it is suggested that reference be made to this paper in order to have a better understanding of the observations which are presented now. These observations enlarge upon parts of the dust control measures already discussed and tell of general progress in the past year. They concern fifty properties, the majority of the operating mines, which vary in size from the hopeful prospect to established producers yielding 11,000 tons of ore daily. Most of these are gold mines; a few copper-nickel. The ores range from heavy sulphides to siliceous materials and they are mined by many methods from varying types of deposits. The majority of the latter are steeply dipping and all are found in Precambrian host-rocks. Up to the present, die greatest depth to which mining has penetrated is 6,400 feet.

Jan 1, 1939

By R. H. Andrews, F. J. West

"Jones & Laughlin Mining Company, Ltd. operate the Adams mine at Kirkland Lake, Ontario, where they mine approximately 4,000,000 tons of extremely hard iron-formation and 3,500,000 tons of volcanic waste rock annually in order to produce 1,100,000 tons of iron pellets. This paper will discuss the maintenance of the four Model 1600 P & H shovels and the two 50-R drills used to obtain this production. The chief maintenance problems at the mine are due to the hard, abrasive ore and the cold winter weather."

Jan 1, 1970

By George Langford

Introduction The fiftieth anniversary is, for an individual or a society, an appropriate time for a review of the past so that events and experiences may be viewed m perspective, and thereby serve as a useful guide to the future. In this review of mining geology it is proposed to set forth the situation as it was when the Institute was founded, and then trace the developments during three appropriate periods-the first from 1898 to 1918 the second from 1919 to 1939 and the third from 1939 to 1948. Mining activities were widespread in Canada in 1898 and some of the operations were considered large for their day. The total value of the metals produced in that year was $21,705,854, and in the case of five metals the output had a value in excess of one million dollars. In order of importance these were gold, silver, copper, nickel, and lead. The important producing areas were ova Scotia, Quebec, Ontario British Columbia, and Yukon. This diversification of the mining areas and the metals produced created an interest in mining throughout Canada, and was an important factor in making Canadians conscious of their mining industry. In the year 1898 geology was a recognized science. The principles of physical geology were well known, but the same cannot be said of economic geology and structural geology. Ore deposits and their occurrence had been studied chiefly in Europe. A great many important observations had been made but the theories linking these facts together were still m a formative stage. The same condition was true of structural geology. These two branches of geological science which are so important in what is now called 'mining geology', had not progressed far enough to be of practical assistance mining operations. For this reason, geologists were regarded as dreamers in ivory towers-a concept chat still lingers in the minds of those who have not kept abreast of the growth of the science.

Jan 1, 1948

By D. A. Livingstone

Abstract Golden Manitou Mines, Limited, nine miles east of the town of Val d'Or in northwestern Quebec, are presently milling, at the rate of 1,000 tons daily, a relatively complex 3.11-phide ore and producing, in decreasing order of value, zinc, silver, gold, lead, and copper. The products are a zinc concentrate, a silver-lead-copper concentrate, and a silver-gold precipitate from cyanidation. Although several independent pre-production metallurgical investigations into the treatment of the ore were carried out, current practice is different from any of the recommended methods and, while still leaving room for improvement, is considerably more effective than earlier performance. Flow-sheet developments from the commencement of operations in 1942 are dealt with briefly, showing the reasons for making numerous changes, the shortcomings of the various schemes tried, and, finally, covering data pertinent to present-day practice. From the recovery standpoint, silver has presented the greatest difficulty. The writer's association with the Company coincided with the start of production. Characteristics of the Ore The predominant metallic minerals present in the ore, in decreasing order of their abundance, are: pyrite, sphalerite, galena and chalcopyrite, with lesser amounts of argentiferous tennantite-tetrahedrite, arsenopyrite, covellite, bornite, and chalcocite. The sphalerite is mostly light in colour, sometimes colourless, and practically free from combined iron. Some of the sphalerite is very closely associated with minor amounts of pyrite, chalcopyrite, and galena. Pyrie is abundantly disseminated as medium to fine grains; more rarely it is massive and contains occasional grains of sphalerite, galena, and chalcopyrite.

Jan 1, 1952

By D. Campbell Mackenzie

THIS paper is submitted primarily to put on record the results of a number of experiments carried out at the Wingdam mine of Consolidated Gold Alluvials of B.C., Ltd., with the object of establishing a reliable method of concentration of 'wash' and a maximum recovery of gold from the concentrate. It will be generally admitted that, during the last two decades, a tremendous amount of research work has been carried out, both by private companies and Government departments, with a view to improving the technique of the recovery of gold .from quartz veins or lodes. So thorough have been these investigations that milling practice at a modern quartz gold mine is almost an exact science, carried out with meticulous accuracy. In placer mining, on the other hand, very little departure from old traditional methods can be noted, with the exception perhaps of the more modern gold dredges. This may be due to the fact that the concentration of placer gravels, up to a certain point, is comparatively easy. Only a simple equipment of sluice box and riffies seems necessary where the gold is coarse and the gravel free from clay. In the early days of placer mining, when claims were rich and fairly 5hallow, nobody worried very much about fine gold; and, if clay was present, an enlarged dump box was constructed in which the gravel was subjected to a rather desultory puddling. That large quantities of gold are lost in normal placer practice is generally admitted. Some 26 years ago, I had inspectorial charge of many bucket dredges on the Ovens river, in Australia. Occasionally it was necessary for a dredge to work through its own tailing to reach a new section, and almost without exception enough gold was recovered from these tailings to defray the total cost of moving the dredge. Since those days, the technique of gold recovery in dredging has been considerably improved and it is still receiving close attention. Outside of dredge mining, most placer operations, deep or otherwise, are as they were-notorious gold losers, paying little attention to the recovery of fine gold and taking an absurd amount of time over each clean-up. In the Cariboo district of British Columbia, the alluvial gold is usual y associated with varying quantities of black sand (magnetic) and grey sand (non-magnetic); and it can be taken as axiomatic that, if you save all the black sand and grey sand, you save practically all the gold. It is on this hypothesis that we have carried out our research work and brought our recovery system up to its present highly satisfactory standard.

Jan 1, 1937

By Christopher R. Lattanzi

"Discounted cash flow analysis provides a means of relating the magnitude of expected future cash profits to the magnitude of the initial cash investment required to purchase an asset or to develop it for commercial production. The objectives of discounted cash flow analysis are to determine:.. The net present value of a stream of expected future cash revenues and expenditures... The rate of return which the expected future cash flows will yield on a given level of initial cash investment.In the case of mineral properties, discounted cash flow analysis is generally accepted as the preferred method of valuation, whenever sufficient data are available to permit its reasoned application. Sufficient data are required to support estimation of all of the individual elements of cash revenue and cash expenditure which will be associated with the development and operation of the property, up to the end of its estimated life. It is the accuracy of these input estimates which determines the validity of the resulting determinations of profitability and rate of return on invested capital.In undertaking any discounted cash flow analysis, it is important to recognize certain fundamental attributes of the mining industty:.. The basis of any mineral development is the existence of an ore reserve... Costs are determined by the number of tonnes mined and processed, while revenues are determined by the number of pounds or ounces of metal produced. The two are related by the recovered grade of the ore... Profit is typically more sensitive to changes in revenue than it is to changes in cost... Commodity price is a principal determinant of revenue, but it is also the factor with which is associated the greatest level of financial risk.In the end, of all of the factors which must be considered in the discounted cash flow valuation of a mineral property, the most significant are the reliability of the reserve estimate, particularly with respect to recovered grade, the price at which the product is to be sold, and the risk of not maintaining the projected level of price."

Jan 1, 2003

By W. D. C. MacKenzie

IT IS almost exactly fifteen years since the discovery of the Leduc oil field and, as this luncheon is part of the Thirteenth Annual Technical Meeting of the Institute's Petroleum and Natural Gas Division, it seems, therefore, a singularly appropriate time to discuss the theme which the program committee has suggested for the occasion -the progress of the Canadian oil industry during the fifteen years since the discovery of the Leduc field. As you will see, I plan to take a few minor liberties with this suggested theme. I shall present ample evidence of growth and progress, but, at the same time, I want to refer to some areas where progress has been anything but conspicuous and to see what can be learned from these areas for the future. The achievements of the Canadian oil industry since the Leduc discovery in 1947 have been substantial, and the public is relatively familiar with the more spectacular developments.

Jan 1, 1962

By John Stoten

"The 1980s have proven extremely difficult years for many resource-based organizations. Mining companies have learned how to weather the negative effects of inevitable economic cycles. However, with some notable exceptions, such as gold mining companies, the mining industry has faced a broader and deeper round of cutbacks than any experienced since the 1930s. Downsizing has been a major issue for many mining companies as they have faced the need for dramatic staffing cost reductions in the recent past.The continuing current rapid rate of change in technology and the marketplace, coupled with increasing merger and acquisition activity, will provide an on-going need for some companies to face major reorganization. This inevitably will involve down-sizing activity in some instances.Given this scenario, it is worth reviewing the industry's past experiences to identify approaches and techniques that could prove of value in handling a future staff downsizing challenge. This paper is based upon a downsizing consultant's experiences with the mining industry and other sectors, and highlights what appear to be key staff reduction planning and process issues.Planning for DownsizingA review of companies' downsizing activities of the last few years reveals four key activity stages which need to be addressed to ensure a successful transition. These stages are:1. organization planning;2. developing cost reduction strategies;3. implementing downsizing; and4. building for the future.A business situation that is severe enough to require drastic staff cuts typically affects all aspects of a company's operations. Most mining companies have reviewed cost efficiencies in many operational areas. However, these reviews often have been short term in focus . As a result, some companies have experienced multiple downsizing; each event a response to an immediate economic threat. This has sometimes resulted in an unstable organizational environment, with severe stresses on staff morale and productivity.In the long term it is more efficient and less stressful to the organization to adopt a more comprehensive and longer-term strategy. Especially in capital intensive mining operations, it makes sense to review all areas of business activity, not just staffing."

Jan 1, 1989

By V. C. Pandolfelli, L. Paulino, C. E. Zangiacomi

The continuous improvement in aluminum industry over the last years has increased metal output at lower cost. The potlining plays an important role in this regard due to high cost involved and more recently in its environmental aspects. In order to increase potlife and thus minimize the aluminum cash cost, a systemic approach is needed, through investigating the main cathode failure mechanisms by using a pot autopsy as a powerful tool, and then making the necessary chances to achieve extended potlife. In addition, preheating and pot start-up may also damage the cathode if not performed with an appropriate technique or even if the lining materials are not specified correctly, among other factors. All these aspects will be presented and discussed in this paper. Increased potlife, especially now that the current is reaching values up to 300kA, will allow aluminum plants to match their goals more efficiently at lower costs.

Jan 1, 2006

By Jean-Pierre Côté, Alexandre Noiseux

"Hatch and ArcelorMittal Mines Canada have combined their expertise to develop a dynamic model of the latter’s Iron Ore Pellet Plant in Quebec, Canada. This model was used to predict the benefits of different expansion projects, as well as asses the best implementation sequence.Two modelling tools were used: a discrete-event simulation software used to develop the dynamic model of the Pellet Plant and an in-house process simulator. The latter was based on operational data and known behavior of the process, and was calibrated with historical data gathered under different operating conditions.The results of the process simulator were used as input values for the dynamic model, which included all of the operation steps of the pelletizing process, from concentrate beneficiation to baking of the pellets. The model has been validated by assessing its capacity to represent adequately the operation of the plant during a 20-month operating period. It was able to reproduce the plant capacity within a precision of 1.2%.Simulated “what-if” scenarios allowed quantifying the production increase associated with the addition of new equipment such as ball mills or balling discs, implemented individually or in combination. Results revealed a potential 10% increase in the annual plant production by adding additional equipment in the two most limiting sectors of the plant, grinding and agglomeration. The simulation results made it possible to quantify the synergistic effect of two projects on plant throughput; the model showed that the combination of two projects resulted in a greater production increase than the sum of the same projects evaluated individually.Now that it has proven reliable, the simulation tool can readily be used by ArcelorMittal Mines Canada process engineers to perform simulations for equipment optimization, and to evaluate the impact of various operating parameters such as equipment availability and tonnage, product mix or concentrate quality. This work showed that a reliable model can be developed based on known parameters in combination with the proper integration of the process knowledge."

Jan 1, 2010

By James S. Redpath

"AbstractThis paper is an attempt. to outline the present status of underground mining contracting in Canada, and to present certain facts concerning the writing and administration of underground mining contracts which, hopefully, may be useful to those intending to engage a mining contractor . The paper is based on the author' s experience as a contractor and also as a consulting engineer advising others in the purchase of contractors' services.HistoryIN THE early days of mining contracting in Canada, the contractor was primarily a labour contractor. He was expected to bring a good crew of men that normally followed him, and to perform certain work under his own direct supervision. The owner usually looked after all other details including financing, payrolls, withholding taxes, etc , computing and paying the contractor his profit. In the pre-World-War II years, most work was done on this basis.Over the years, the contractor was called on to supply more in the way of services, and the present-day situation evolved.Labour contracts are still used, but now the contractor is expected to carry out his own administration. Most contracts now call for the supply of special tooling required to do the work. In most cases, some, if not all, supplies are the contractor 's responsibility and , in a growing number of cases, the contractor is responsible for such items as design and surveying. The ultimate in this direction is the execution of projects on a turnkey basis. Under this system , the contractor carries the project to a stage where it is turned over fully operational to the owner."

Jan 1, 1977

By Denis Yaychuk, Gary Billingsley

The economic eva luation of a mineral property or mining venture should include the quantification of ri k as part of the analy is. The re ults of such an analysis provide the decision-makers not only with the most likely financial outcome and the probability of achieving that or any other outcome. but al o with a ranki ng of the relative impact of all the ri sk factors. These type of resu lts offer more complete information for investment and technical deci ions than the traditional cash flow/ ensitivity analysis. In addi tion. by attempting to quantify ri sk. the personnel providing the va ri able input are forced to take a much clo e r look at the data involved, and are fo rced to work together. the reby increa ing substantially the awa reness of the impact their work and others· work has on th e outcome of the analysis.

Jan 1, 1986

By Elaine R. Goetz

The eastern and southeastern regions of Ohio are part of Appalachian coal country, with a documented 1,300 miles of streams impacted by acid mine drainage. Since 1995, partnerships of local watershed groups, government agencies, private industries and universities have focused on the remediation of the affected waterways. The partnerships have spent $2.4 million annually in constructing and operating treatment systems such as wetlands, anoxic limestone drains, successive alkalinity production systems, steel slag leach beds, and lime dosers. These systems have been partially successful, and water quality has improved in the region, but no treatment has yet met the ultimate objectives of low cost, continual remediation. Our research group has investigated an alternative system for acid mine drainage treatment: electrolysis combined with pH adjustment to selectively precipitate recoverable, saleable metal products to offset the cost of treatment. We utilized a $0.2 million pilot facility constructed by the Wayne National Forest, in Nelsonville, Ohio, to process approximately 40 L/min of mine drainage from surrounding seeps. The pilot facility has multipurpose tanks that can be adapted to process acid mine drainage with different characteristics, such as high or low aluminum content or high or low carbonate concentrations. Sodium hydroxide was used for pH adjustment. Results indicate that saleable product can be generated with this treatment technology. In an initial, not optimized trial, one seep yielded 4.7 kg of dried 69 % iron oxide product from 10 hours of pilot facility operation, treating 23,000 L with electricity costs of $4.68. Dissolved iron concentrations in the water were reduced from 242 ± 18 mg/L to 2.8 ± 2.0 mg/L (99.0 % removal) while the initial acidity of 443 mg/L as CaCO3 was neutralized to an alkalinity of 160 mg/L as CaCO3. Iron oxide can be sold as pigment for an average of $1.47 per kg in the United States. Currently, approximately 80 % of all pigment used in the United States is imported, and there is incentive to purchase domestically recovered pigment. If the iron oxide from the pilot facility could be sold as pigment for $1.47 per kg, 43 % of the operating cost (raw materials, electricity and construction costs) of treatment could be offset by the sale of the product. Considering the cost offset, the electrolysis process shows potential as a sustainable low cost alternative for treating acid mine drainage.

Aug 1, 2013

By N. Novikov, M. Jastrzebski, N. Kryzhanovskaya, D. Shevchenko, I. Kapran, N. V. Novikov, T. Koehler, B. Zaporozhets

"The PFK FeNi Smelter was re-commissioned by Solway Resources in 2002, ending a long period of economic decline in the adjacent town. In 2009 Hatch was retained to design, supply and install a custom furnace crucible that would accommodate a capacity increase from 34 MW to 40 MW and increase campaign life through binding and cooling technologies, as part of ongoing improvement efforts. The involvement of PFK personnel was critical to the successful integration of the new furnace technology with the existing process and operational practice. The furnace upgrade project was completed in 18 months during 2010 – 2011. Since start-up, the furnace has exceeded production expectations, operating successfully at 42 MW.INTRODUCTIONAfter ceasing operations in the 1990’s, the Pobuzhsky Ferronickel Combine (PFK), located in central Ukraine, was stripped of useful equipment and deteriorated while dormant. The surrounding town experienced a period of economic decline throughout the 1990’s. Solway Industries purchased the complex in 2002 and began a systematic incremental program to re-commission the smelter using both local expertise and specialists from other parts of the former Soviet Union. This led to the re-birth of PFK as a successful toll-smelting complex, and a renaissance for the surrounding economy.As part of the continuing improvement program, PFK approached Hatch in 2009 to study the possibility of a capacity expansion from 34 MW to 40 MW. It was decided, based on the results of the study, to design and install a custom furnace crucible integrating the unique PFK FeNi process with modern Hatch furnace technology. This novel approach had many benefits, including: maximum re-use of existing furnace components (off-gas, feed equipment and transformers), minimal impact on upstream and downstream equipment and building structure, and the retention of a familiar operating regime. The latter was a key factor in the success of the project, as it allowed the extensive operating expertise of the PFK staff to remain highly relevant to the upgraded furnace. This led to minimized capital investment, a rapid start-up and no significant operational challenges switching over to the new equipment incorporating Hatch furnace technology."

Jan 1, 2012

By Thomas G. Madgwick

Introduction Development of oil and gas is still centred in the Province of Alberta, much as it was when C. C. Ross read a paper on this subject three years ago at the Annual General Meeting in Montreal; but so far as gas is concerned, its early production in Saskatchewan seems now assured. The three years that have elapsed since Mr. Ross' paper have witnessed a growth in the world's production of oil that has created a potential supply out of all proportion to the demand for petroleum products, and one that has resisted the most energetic efforts of the industry entirely to control. The natural result has been very much to retard the active prospecting of new structures in the Prairie Provinces with any immediate view to oil production, although the same factor has not hindered the search for gas to the same extent. One consequence has been to divert the attention of organized oil operators from wildcat drilling to more detailed geological investigation than had hitherto been customary, sometimes accompanied by test drilling with a view to the elucidation of geological structure rather than to the immediate development of production which at the present is not needed. Nevertheless, in spite of the growth of this phase of oil prospecting - which the writer would be the last not to welcome as a very real blessing and of far greater value than indiscriminate wildcat drilling in either the complex structures of the foothills or the simpler but largely concealed formations of the plains- it is most satisfactory to have to record that in these three years the growth of production both of naphtha and the heavier crude-oil has kept pace with the by no means inconsiderable growth in the production and utilization of natural gas.

Jan 1, 1929

By E. Swartzman

"IntroductionGENERALLY, the necessity for mining coals of higher impurity content, the drive for lower costs by intensive mine mechanization, changing market requirements, and the increasing competition of oil and natural gas, have continued to result in an upward rise in coal preparation, and have necessitated a more intensive study of coal preparation problems.Increasing adoption of •continuous mining equipment, for example, is introducing new problems in coal preparation. Limited experimental work in the United States (1) shows that the effect of the continuous miner on size distribution varies with the characteristics of the seam. In some seams, the fines problem is lessened, in others it is greatly aggravated. Generally there is a decrease in the relative amount of the top sizes (plus 2 in.) and a substantial increase in the intermediate sizes (down to about 1/8 in.). Contrary to expected results•, where continuous miners with vertical-moving cutting heads are used, an increase in impurities in the slack sizes does not necessarily occur where draw-slate is taken. This is because the draw-slate tends to be kicked out in lump form. However, if a seam contains bands •and lenses of impurities they are bound to be in the mined product."

Jan 1, 1952

By Mel Torrie

1 Want access to low level vehicle data so 3rd party apps can be applied as desired 2 Hardware Agnostic (COTS plug and play) 3 Common/Open protocols that facilitate integration and the coexistence of a variety of applications on a variety of equipment 4 Minimum computer hardware footprint 5 Technology Independence (including comm. backbone)

May 1, 2013