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By M. Y. Levesque

The Australian Government?s Energy Efficiency Opportunities (EEO) program launched in 2006 obliges companies that use more than 0.5 PJ (petajoule) or roughly 139 GWh (gigawatt hour) per year to conduct an energy assessment in order to identify measures to improve energy efficiency. The opportunities identified by the mining sector were assembled in the Mining Significant Opportunities Register that permitted companies not yet embracing and adopting an energy management program to see what those who are, were doing and how much energy was saved, and helps disseminate best practice. The measures can be filtered by company, year, category or equipment type. The creation of a central repository of energy efficiency initiatives is valuable but this existing database could be improved; fields identifying the energy and carbon emission savings associated with a given initiative are a surprising omission. Consequently it does not permit the relative effectiveness of different measures for energy and carbon reductions to be readily assessed. A review of energy management efforts implemented in the mining industry, published in peer reviewed journals, corporate sustainability reports or industry publications during the last 40 years has revealed many examples of best practice. However, the lack of a standardized reporting framework in any of these sources has made it difficult to assess the effectiveness and compare the adopted energy management measures ? just as is the case with the Australian register. In an attempt to address these issues, an improved database structure has been created for energy management measures from the mining industry which identifies energy and financial savings arising from energy management initiatives, classifies applications to specific processes or equipment, and recognizes leaders in the mining industry with respect to energy management. The structure of the register includes the key data relevant to energy management in mining that is absent in the Australian version. The mining industry energy management database has been made available in the public domain where stakeholders can examine the best practice examples. Mining energy champions may also contribute to the register by providing case studies; a standardized entry template affords a quality assurance dimension that is absent in other reporting initiatives. Adoption of this database with its standardized reporting mechanism will enhance transparency of the mining industry in energy matters and help it maintain its social license to operate.

Aug 1, 2013

By H. Lee

Recently, the effects of global climate changes have become top concerns for governments? decision making regarding infrastructure investments. Extreme weather events that exceed the capacity of existing systems have considerably increased in frequency, and the potential effects of changing trends in temperature and rainfall on infrastructure are difficult to ignore. It is essential for governments to estimate the costs and benefits of adaptation to climate change to properly assess the financial feasibility of infrastructure adaptation strategies. This paper proposes a framework for estimating the economic aspects of infrastructure adaptation to climate change. The framework is composed of three steps of implementation: establishment of alternatives for infrastructure adaptation, performance prediction of infrastructure using future climate scenarios, and asset valuation based on costs and benefits. The first step specifies target assets, their adaptability to climate change, and applicable adaptation technologies. The second step evaluates the effects of climate change on the performance of infrastructure. The last step determines the optimal adaptation strategies among various alternatives based on their net benefits. The framework reasonably incorporates future climate scenarios into the estimation processes for climate change effects and provides a basis for budget allocation for governmental infrastructure investments. The framework is expected to assist government decision makers in establishing adaptation strategies in a rational manner under uncertain future climate change.

Aug 1, 2013

By A. Bouajila1

Minerals processing organisations will be more and more under intense competitive pressure. Major changes are being experienced with intense respect to resources, processes, production strategies and markets. As result of international competition, only the most productive and cost-effective operations will survive. That is why operators in the minerals industry have always aimed to obtain better performance from their processes along the mineral extraction cycle starting from exploration up to the smelting step if any. A principal ingredient and perhaps the most important one in the process of evolution toward improved productivity is the achievement and implementation of an error-free production synonym of an ignorance-free operation. This is, at the same time, a guarantee for quality, a minimising factor for waste materials production, handling and disposal, and a maximising factor for labour utilisation. The notion of ?error or ignorance-free? -usually identified as a ?made in Japan? manufacturing mythology, will sound, at first impression, like a pious ideal, to be striven for but impossible to attain. Nevertheless, the introduction of measurement and detection technology in the minerals industry along the last century should benefit from the today?s sensors and control systems that explosively expanded beyond their traditional production base into far-ranging commercial ventures. The fastness and spread of those technologies will play an important role in the survival of innovative plants. Their role in information assimilation, and control of operations to maintain an error-free production environment, will help many plants to stay effective on their competitive course. In this paper the feasibility of the zero process ignorance concept as applied to the comminution circuits will be discussed and the challenge behind this ambitious move toward improved productivity will be outlined. Examples of pre-competitive R&D projects started at COREM in order to fulfil this prerogative will be presented.

May 1, 2001

By T. D. Traubert, J. T. Dietz, D. Catena

"Canadian process industry experts have often observed the strong trend for U.S. industrial safety and environmental laws to creep across the border. These experts will be interested in new United States (OSHA) regulations (29 CFR 1910.119), and anticipated new U.S. Environmental Protection Agency (EPA) regulations that will require over 28 000 U.S. refineries and chemical plants employing more than three million workers, to begin a comprehensive Process Hazard Analysis (PHA) of these complex plants immediately. Impending EPA regulations are expected to expand these efforts and add process Hazard Frequency and process Hazard Consequence reviews for many additional industrial locations.These regulations were created to reduce catastrophic industrial accidents, and emergency releases of hazardous chemicals which endanger employees, the public, and the environment.Accurate, and field verified Piping and Instrument Diagrams (P&IDs) are essential to permit a meaningful Process Hazard Analysis or emission release to be done. Today accurate P&IDs often do not exist. Many companies that have started to update their old P&IDs have found the process to be far more difficult, time-consuming,and expensive than they ever thought.This paper describes a new technique of computer drawn ""Intelligent"" P&IDs that can make a Process Hazard Analysis less expensive, more accurate, easier to perform, and provides lasting benefits to the plant owner long after the PHA has been completed."

Jan 1, 1993

By C. W. Eggert

"The idea for this talk came to me last year when I was attending the Canadian Gold Metallurgists Meeting. I talked about it to a friend of mine who is an authority on mineral dressing, particularly the theoretical end of the business. He remarked that this was an excellent technical note, why don't you write it up. This is what I have for presentation this morning. I hope in presenting this type of idea in this way it is in keeping with the tradition of the Canadian Gold Metallurgists which was to function on a not too sophisticated level and where operators could get together and trade ideas in an informal way.My basic thesis is that it should be possible to evaluate screen analyses by the application of the standard statistical probability theory. In any statistical analysis the sample is the first consideration. If we look at existing methods of size evaluation we find it is usually based on the fact that a given particle will pass one square aperature and not another. One system of standardizing how these aperatures will be set up is based on Rittenger' s work with the ratio of hole sizes proportional to the square root of 2. Keeping in mind the limitation we have accepted this as our method of 11 sizing"" in attempting to apply standard statistical methods to screen analysis."

Jan 1, 1968

By Donald A. Cranstone

Donald Cranstone holds B.Sc. (Honours) and M.Sc. degrees in Geology from the University of Manitoba and a Ph.D. in Economic Geology from Harvard University. He has worked as a mine geologist, a provincial geological survey geologist and as a senior exploration geologist. He joined what is now the Minerals and Metals Sector of Natural Resources Canada in 1971, where he has been a commodity specialist for gold, for copper and another 28 metals. He is a senior mineral economist, currently engaged in analysis of mineral exploration and discovery success in Canada and of the future of the Canadian mining industry. Abstract This paper examines the history of Canadian non-petroleum mineral production. The outlook over the next 25 years, for mining in Canada and in each province and territory, is reviewed. The outlook for mining in Canada and in most provinces/territories is favourable, but problems seem likely in a few jurisdictions unless new orebodies are brought into production. In terms of exploration potential, Canada consistently ranks among the top three countries in the world. Over the last eight years, Canada has consistently been second only to Australia as a destination for exploration investment. For the first time, Canada is ranked in terms of total mineral production, including coal and construction materials, relative to all the countries of the world including countries of the former communist bloc.

May 1, 2001

By Nelson C. White

This paper summarizes the present state and future prospects of the potash industry, with special reference to its impact on production in Saskatchewan.

Jan 1, 1968

The influence of joint orientation and joint persistence, on the mechanical behaviour of jointed rock masses under uniaxial compression, has been studied systematically. The joint inclination angle ß was varied from 0° to 90° with an increment of 15°. The joint continuity factor k was taken as 0.2, 0.4, 0.6 and 0.8. The peak strength, Young’s modulus, the complete axial stress-axial strain curves, the cracking process and the characteristic of the fragments, were investigated. It was found that the anisotropic response of the jointed specimens was governed by the micro-mechanism, such as crack initiation, propagation and coalescence, crack opening or closing, and frictional slip of cracks or joints. With the increase of joint continuity factor, the axial stress-axial strain curves change from single-peak to multipeak, the peak strength and Young’s modulus decrease. The specimens with medium joint inclination angle (30°,45° and 60°) has lower energy dissipation and strength due to stepped or shear failure, while specimens with small and large joint inclination angle (0°, 15°, 75° and 90°) has higher energy dissipation and strength due to axial cleavage or crushing failure.

Jan 1, 2015

By G. K. Herzog

THE problems relating to the construction and use o{ mining equipment are basically the same as those pertaining to equipment in other industries. It is true that much mining equipment is subjected to an unusually severe combination of shock, high stresses, abrasive wear, and corrosive ? conditions, but in other industries, also, equipment must operate under similar adverse conditions, so that their experiences may readily be applied to the problems of the mining industry. Steel and iron are for obvious reasons the most suitable materials for the construction of the greater part of the equipment used in the mining industry. For a large percentage of uses, the ordinary plain carbon-steels and ordinary or unalloyed cast-iron are, and probably will continue to be for a long rime, entirely satisfactory materials. There are, however, many. conditions which cannot be satisfactorily taken care of by these materials, and alloy steels and irons must be used where the greatest possible economy is desired. In general, alloy steels and irons are used where it is necessary or economically desirable to use materials possessing properties superior to plain carbon-steel or ordinary cast-irons, such as: (a) better strength (b) better wear resistance (c) better corrosion resistance (d) better resistance to high temperatures (e) better resistance to low temperatures or combinations of two or more of these advantages. There are also conditions where materials having other special properties are required, such as, for example, certain magnetic or electrical properties for electrical machinery; but in the great majority of cases, one or more of the five advantages listed are the most desired.

Jan 1, 1938

By David Lewin

The journey toward cleaner coal-fired power generation is driven by technological improvements, more stringent regulations around greenhouse gas and other air emissions, and the potential of one of Canada?s most abundant resources. Within this context, EPCOR is leading efforts to commercialize gasification technology to produce electricity with near-zero emissions. By turning coal, oxygen, and water into synthesis gas through a gasification process ? and then capturing CO2 ? it is possible to dramatically reduce greenhouse gas and smog-related emissions. EPCOR is conducting front-end engineering and design work on an Integrated Gasification Combined Cycle technology (IGCC) utility-scale plant ? in conjunction with the Canadian Clean Power Coalition ? at its Genesee site, west of Edmonton. EPCOR, the Alberta Energy Research Institute, and Natural Resources Canada have each contributed $11 million to the $33 million project. A critical element of the project features the capture of CO2, which would be piped underground for long-term sequestration, or for use in enhanced oil recovery (EOR). The combination of IGCC and CO2 sequestration, at this scale, has not been used anywhere else in the world.

May 1, 2008

By E. A. Collins

I TAKE it that the papers presented tonight on the subject of Reconstruction, as regards both gold and base-metals, are intended primarily to stimulate discussion of this important subject and, in regard to base-metals in particular, cannot in any manner be considered as a policy or plan to be followed as a panacea for all the ills which are bound to beset the industry when peace is declared. A famous cook-book written by a Mrs. Beeton contained a recipe for jugged hare which began with the instruction, "First catch your hare". To date, we have not caught the hare of victory and it may seem to many that any thought, energy, or effort devoted to the problem of reconstruction which will in any way impede the acceleration of the chase after victory will leave us open to the charge of being derelict in our duty as citizens. Much of our present trouble is due, however, to our lack of preparation for war in time of peace, and it follows that it is of equal importance in our national economy to prepare for peace in time of war. Most of us here tonight have vivid and sad memories of the chaos in the metal mining industry following the Great War of 1914-1918. In our own industry, mining, smelting and refining of nickel and copper, it was not a problem of absorbing the men who returned. There were only some three hundred who came back to the Mining and Smelting Division, and these men were all given their former jobs without any apparent difficulty. They were rehabilitated gradually due to the fact: that some of these men did not return for a year after the Armistice was signed. The numbers of men involved in the present conflict are much greater. We have to date in the armed forces upwards of 3,000 men enlisted from our employ.

Jan 1, 1943

By David J. McDougall

"The production of pig iron, wrought iron bars and castings in Quebec during the 18th and 19th centuries has been so closely identified by historians with Les Forges du St. Maurice on the St. Maurice River a few miles north of Trois Rivieres (Three Rivers), that one is sometimes left with the impression that it was the only iron works that ever operated in the province. There were however, about twelve others, one of which was so completely re-built that it should probably be considered as a separate entity. All but two were constructed after the midpoint of the 1800s, coinciding with the growing Canadian demand for ""charcoal pig"" for railway car wheels and castings for industry, and about half of them were technically, if not economically, successful. The misconception about Les Forges du St. Maurice may have come about either because of its long history of somewhat less than continuous production over a century and a half, or a tendency of Quebec historians to concentrate on events in the French-Canadian milieu, but whatever the reason, the other Quebec iron works have been generally ignored. All but one of the Quebec blast furnaces could be described as ""pre-industrial"" with capacities ranging between three and ten tons per day, the exception being the Radnor furnace built in 1892 with a maximum production of about 35 tons per day and an alleged capacity of 50 tons per day. Until a railway network was completed in the 1880s, the location of all the Quebec iron works except the Grantham Iron works was dictated by close proximity to adequate ore reserves because horse transport was of little use beyond a ten-mile radius. The other essentials of forest resources (mainly soft woods) for charcoal, limestone for flux and water power, were generally available except within a few miles on either side of the St. Lawrence River. Among the dozen iron works established in Quebec between 1732 and 1880, seven used bog iron ore in charcoal-fired furnaces. Five of these, including Les Forges du St. Maurice, were located on or near the St. Maurice River which enters the St. Lawrence River from the north, and two, the St. Francis Forges and the Grantham Iron works were on or near the St. Francis River which enters the St. Lawrence from the south. In a general way deposits of bog iron ore in the St. Lawrence lowlands of Quebec were contained within the limits of the post-glacial Champlain Sea, with many clustered along the flanks of the St. Narcisse recessional moraine which is crossed by the St. Maurice and other near-by streams, and the Drummondville recessional moraine which is crossed by the St. Francis River."

Jan 1, 1999

By H. C. Cooke

"The Part of the Eastern Townships dealt with in this paper is shown in the accompanying figure. Each rectangle represents one of the topographic maps published by the Department of National Defence on a scale of one mile to one inch. Each sheet covers an area approximately 24 miles long and 17 miles wide, or slightly more than 400 square miles. The north-western part of the area figured, comprising the Upton, Aston, Becancour, and the two unnamed sheets, (Three Rivers and Yamaska), together with most of the Lyster, Drummondville, and St. Hyacinthe sheets, is largely covered by clays and sands deposited in interglacial and post-glacial time in the Champlain estuary, so that outcrops are widely scattered and in-formation is correspondingly sketchy. In the remainder of the area figured, comprising more than 4,000 square miles, outcrops are reasonably numerous and have been mapped on a scale of one mile to one inch, and the structure is moderately well understood.The Eastern Townships was an area of intense orogenic disturbance, apparently beginning late in the Cambrian or early in the Ordovician, and continuing till well on in the Devonian period. During this long period, which may have lasted for a hundred million years or more, the area was subjected from time to time to intense thrusts from the east and southeast. Each of these caused folding of the rocks, accompanied by faulting, raised parts of the area above sea-level, and presumably created ranges of mountains. Long periods of erosion cut away the mountains and reduced the area nearly to sea-level after which subsidence carried it below sea-level, and permitted further sediments to accumulate before the next thrust initiated the next cycle.The first of these movements, as stated, appears to have been in late Cambrian or early Ordovician time. The group of rocks known as Caldwell was folded and, south and east of the town of Asbestos, was thrown into great drag-folds before deposition of the next overlying series, termed the Beauceville, began. Unfortunately, the date of this orogeny is very imperfectly known, because both series of rocks have been so crushed and sheared that almost all fossil remains have been destroyed. Graptolites, found in one place in slates generally considered Beauceville, give that series a tentative Middle Ordovician age. In the Caldwell rocks, which underlie the Beauceville with great unconformity, no fossils whatever have yet been found. Thus, if the Beauceville rocks are correctly dated as mid-Ordovician, the best that can be said of the movement folding the Caldwell is that it took place at some time before Middle Ordovician."

Jan 1, 1949

By C. Y. Lim, H. W. Kim, M. S. Kim, J. H. Cho, Y. S. Lee

Al - 5.5 wt% Mg - 0.3 wt% Cu alloy strip was successfully fabricated by horizontal-type twinroll casting (TRC). For producing sound strips with no surface defect, the casting was conducted at various roll rotation speed, and the sound strip could be obtained at relatively low casting speed (3 rpm). The cast strip was homogenized at 450 °C for 10 hours, and then cold rolled with a reduction rate of 78%, followed by a final annealing at 450 °C for 1 hour. The annealed sheets showed good mechanical properties with approximately 330 MPa in tensile strength and 27 % in elongation, but exhibited strong anisotropy depending on the tensile directions. For the homogenized sheets, warm rolling was also conducted at 200, 300, and 400 °C. The tensile test results of the warm-rolled sheets showed that the rolling at medium temperature (300 °C) was proper to fabricate the sheets with relatively good mechanical properties and low anisotropy.

Jan 1, 2014

By J. D. Galloways

The northern part of the P. G. E. railway traverses and opens up that part of the province known as the Cariboo district, comprising the Cariboo and Quesnel Mining Divisions, which are a part of the Northeastern Mineral Survey District. Williams lake, a divisional point on the P. G. E. is near the southern boundary of the Quesnel Division and from this point the railway runs northerly to Quesnel, its present terminus. From Quesnel the railway is projected and partially constructed to Prince George on the Canadian National railway; therefore its general trend is northerly through the heart of the Cariboo district. Early History There is no need to outline at any length the early history of mining in the Cariboo. It is sufficient to say that the great gold rush to the Cariboo, in the early sixties, was practically the commencement of mining in British Columbia. These early placer mining operations centred around the old towns of Quesnel Forks, Keithley Creek, Barkerville and Van Winkle, the latter now called Stanley. Many millions of dollars of placer gold have been taken out and the end of production is not in sight yet. The maximum yearly production was reached about 1863, after which there was a gradual decline in output. During the war years production was at a very low figure but a steady, even if small, increase has occurred in the last three years and prospects are encouraging for a much greater output.

Jan 1, 1925

By Heather Budney

Objectives 1. Evaluate the effectiveness of ON?s EA processes using criteria from the EA and policy sciences literature. 2. Recommend improvements to the EA processes and draw lessons from the ON case for the consideration of other jurisdictions. Evaluation Process 1. Chose criteria ? 14 primary criteria (Wood 2003) ? Subcriteria from Wood (2003) and Lasswell (1971) 2. Gathered information ? 6 key informant interviews ? Published literature, policies, legislation 3. Assessed criteria and formed Recommendations

May 1, 2008

By A. Kapoor

Gold mill effluents contain toxic pollutants such as cyanide (CN), thiocyanate (CNS), ammonia (NH4-N), and a variety of toxic metals. Various practical and economical technologies are in use for the removal of CN and toxic metals from gold mill effluents, however, the removal of CNS and NH4-N is challenging. The presence of CNS and NH4-N may make effluents toxic to aquatic life. The new Canadian Metal Mining Effluent Regulations will require mine effluents to be nontoxic. As a result, there is a need to develop practical and economical technology for CNS and NH4-N removal. The Mine Effluents Program in the Environment Group is presently evaluating biotechnology processes for the removal of CNS and NH4-N from gold mill effluents. The processes being evaluated are attached growth systems such as a Rotating Biological Contactor (RBC) and completely mixed suspended growth systems such as a Sequencing Batch Reactor (SBR) operating in a batch mode. The research to date at MMSL has shown that the RBC is very effective in removing CNS and NH4-N from simulated effluents. The NH4-N removal project showed that the RBC is capable of removing 0.8 g NH4-N/m2 of RBC disk area per day at an average temperature of 4.5 oC and hydraulic loading rate of 0.02 m3/m2/d. The RBC was also found to be very effective in removing CNS (feed = 200 mg/L and effluent < 1 mg/L) at 8 oC and a hydraulic loading rate of 0.02 m3/m2/d. The SBR was effective in removing CNS and NH4-N (generated from CNS degradation) at SBR operating conditions of two-12 h treatment cycles and a temperature of 12 oC. The end product of CNS and NH4-N oxidation was NO3-N, which is relatively non-toxic.

Nov 1, 2002

By J. Shen

Direct methanol fuel cells have been the subject of considerable research in the last decade. Performance levels realized in cells, stacks, and systems show that this technology is a promising power source for a wide range of portable applications. A direct methanol fuel cell (DMFC) operates directly on a methanol fuel stream typically supplied as a methanol/water vapour or as an aqueous methanol solution in liquid feed DMFCs. The fuel streams in DMFCs are usually recirculated in order to remove carbon dioxide and to re-use the diluent and any unreacted fuel in the depleted fuel stream exiting the DMFC. The concentration of methanol in the fuel circulation loop is an important operating parameter because it determines the electrical performance and efficiency of the direct methanol fuel cell system. The methanol concentration in the circulating fuel stream is usually measured continuously with a suitable sensor, and fresh methanol is admitted in accordance with the signal from the sensor. There are many factors to consider in developing a methanol sensor suitable for DMFCs. These factors include sensitivity, cost, size, simplicity, reliability, longevity, concentration range, and dynamic response. In particular, reliability and low cost should be addressed. Methanol concentration sensors measure methanol concentration by means of detecting the variations of physical/chemical properties of the solution. In this work, methanol concentration sensors based on electrochemistry, electric-capacitance measurement, infrared sensing, ultrasound sensing, and other techniques are reviewed to discuss their advantages and disadvantages.

Jan 1, 2005

By William A. Napier

The Mantaro Phosphate Property is located ~ 250 km east of Lima, Peru in the Andean altiplano near the city of Huancayo, Junin District. The Mantaro deposit is a mineralized zone of phosphatic rock currently defined by surface outcrops, trenches and drilling extending over a strike length of more than 30 km and a width of more than 5 km covering ~27,700 hectares. Mineralization is exposed as three roughly parallel exposures (?mantos?) trending in a northwest-southeast direction along the Mancaspico syncline. Estimated mineral resources1 contained in Manto 1 of the Property (4% P2O5 cut-off) as of February 21, 2010, are: Measured 5.548 million tonnes @ 10.8% P2O5 Indicated 33.975 million tonnes @ 9.9% P2O5 Measured + Indicated 39.523 million tonnes @ 10.0 % P2O5 Inferred² 376.265 million tonnes @ 9.0% P2O5 1Tonnes rounded to the nearest 1,000 and grade to 1 decimal place. 2Inferred material reported with no cut-off and an assumed grade. There is considerable potential to expand the resource base. Mantos 2 and 3 of the deposit have been geologically mapped and exhibit surface mineralization widths similar to Manto 1. Given that the deposit is of marine sedimentary origin, it is reasonable to infer that comparable grades and depth of mineralization are present within Mantos 2 and 3. Based on this assumption, the potential mineral deposits within Mantos 2 and 3 are estimated to be approximately: Manto 2 425-435 million tonnes @ 9% P2O5 Manto 3 280-290 million tonnes @ 9 % P2O5 These potential quantities and grade are conceptual in nature, there has been insufficient exploration to define a mineral resource and it is uncertain if further exploration will result in these targets being delineated as a mineral resource. However, should such conceptual resources be confirmed by trenching and drilling, the Mantaro Phosphate Property would rank as one of the most significant phosphate deposits in the world.

May 1, 2011

By M. Dosoudil

"Continuous pressure filtration is a modern process for the mechanical dewatering of flotation concentrates of coal and similar coal slurries. This method will give a lower moisture content than classical vacuum filtration, the improvement lying in the range 5% to 15%. Eighteen coal slurries have been examined in this survey. They are representative of a wide spectrum of filtered slurries. IntroductionDuring the last five years, a number of coal slurries have been tested either in the laboratory or with a pilot plant. The test pressure ranged from one to six bar. The results have been evaluated by mean s of a computer. Determination of the filter capacity and the resulting moisture content and energy consumption has been made with respect to the continuous pressure filter, Amafilter construction-type KDF (Fig. I) . Standard sizes of these filters are 60 m2, 90 m2 and 120 m2.The continuous pressure filter is a horizontal filter with a level tank. Six filter axles are mounted on a rotating main shaft, each with a particular number of elements attached. The elements rotate on their axes and move along a circular trajectory. Periodically the elements submerge into and emerge out of the slurry. A constant air pressure is maintained above the suspension, thus providing the pressure gradient necessary for filtration. The filtrate together with the dewatering air flows through the elements into the hollow axle and out of the filter."

Jan 1, 1987