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By W. A. Lang

Introduction In this review, which is the fifth of the series on the Progress in Coal Technology, an attempt has been made to outline some of the more important developments that have taken place in coal carbonization during the last decade. Research into both high-and low-temperature carbonization has been active for three principal reasons: (1) the growing shortages in most countries of high-quality coking coals; (2) the demand for smokeless fuels for domestic purposes; (3) the need for metallurgical coke for the increased output of steel in the post-war years. The growing importance of coal tars as a source of chemicals for the preparation of synthetic products and of coal gases for the recovery of sulphur is evident. Many of the researches initiated because of wartime necessity have been continued .and even expanded in the post-war years. High-temperature carbonization with a suitable coal yields a strong coke which is used primarily for metallurgical purposes, a tar with good marketable value, and a large yield of gas of medium calorific value. Low-temperature carbonization gives a more free-burning solid product suitable for a domestic fuel, a high yield of a tar which is generally regarded as superior to high-temperature tar for chemical purposes, and a smaller yield of a higher-heat-value gas.

Jan 1, 1951

By R. J. Traill

Introduction Following the discovery of high-grade deposits of pitchblende in the Great Bear Lake area of the Northwest Territories by Mr. Gilbert LaBine in May, 1930, samples were submitted to the Mines Branch for examination and investigation as to suitable methods of treatment (1). The purpose of this paper is to present, briefly, the results of the investigative work conducted on the ores and an outline of the methods developed for the extraction of the radium content and recovery of the by-products. The paper is presented in two parts. Part I gives a review of the history of radium production and of the principal processes used in other countries. Part II describes the work and gives the results of the Mines Branch investigation. Part 1-Radium Production In Other Countries Historical Outline Uranium was discovered in 1789, and more than a century later Madame Curie, while studying the physical properties of this element, observed that the ore of uranium exhibited greater activity than the pure uranium com-pounds she had prepared and traced the cause to the presence of a new element which she named radium. Eventually, research proved radium to be a disintegration product of uranium, and always present in uranium ores.

Jan 1, 1933

By Alan Bauer

New developments in drilling, blasting and explosives in both open-pit and underground mining operations are discussed, as well as novel surface blasting techniques such as are used in tar sand mining.

Jan 1, 1978

By F W. Irwin

In recent years, a number of significant developments have occurred in the steel industry which are no-table and of general interest. This paper is confined to the steel-melting phase of the business. The development of high production rates on Stelco's Basic Open Hearth furnaces is chronologically summarized. Al-though various aspects of this subject have been presented previously, this paper summarizes the developments in high fuel rates, the usage of basic refractories, low and high oxygen rates and hearth maintenance. Background T HE interest which has been shown in steelmaking techniques in the past few years has been due, primarily, to the extremely high production rates obtained. Upon further study of the facilities and techniques employed to generate this steel at record rates, tonnage oxygen appears as the common factor. It can be stated that tonnage oxy-gen has revolutionized steelmaking techniques to a degree never before encountered. It was only about ten years ago that the use of large amounts of pure oxygen in a steelmaking

Jan 1, 1965

By A Palynchuk

The development of welded pipe has paralleled the general industrial development and, in particular, that of the petroleum industry. The petroleum industry's need for high-grade, economical pipeline material to make many 'of its projects feasible has been a significant factor in the development of light-wall, high-grade welded pipe. The modern welding processes, such as high-frequency, electric resistance, flash, submerged arc, etc., have some basically different characteristics. The modern high-frequency weld mill is a complex of specialized equipment that is integrated into a production unit. Each component in the unit performs a specific function in the production process. Quality control must be built into the process on an operating basis and, to maintain the quality required for pipeline standards, must be more than a policing operation. The further development of the welded pipe industry will be determined by changing and increasing demands. The technical and economic views and requirements that will influence the development have to be resolved.

Jan 1, 1964

By Yvon T. Maurice

Under the auspices of the Federal-Provincial Uranium Reconnaissance Program, a geochemical orientation survey was undertaken in an area of uraniferous Lower Proterozoic (Aphebian) rocks near Cape Dorset in southwest Baffin Island. The main objective of this study was to establish a methodology for a future reconnaissance geochemical program using lake samples over a 300-mile Lower Proterozoic rock belt that occurs along the southern coast of Baffin Island. Mineralogical and chemical studies of known radioactive occurrences, combined with detailed sampling of secondary environment media in the vicinity of the showings. indicate that uranium is the most significant pathfinder, despite considerable enrichment of other metals in the uraniferous rocks, Significant geochemical patterns produced by uranium in lake waters and uranium in lake sediments have been obtained, but their relative usefulness depends on the distribution of carbonate bedrock, which in turn affect the bicarbonate content of lake waters. In southern Baffin Island, because of erratic variation in lake-water alkalinity, it is recommended that both water s and sediments be sampled on a routine basis. The need for lake-water acidification to prevent depletion of soluble metal ions in samples resulting from adsorption on the walls of the containers and/or suspended solid matter is discussed briefly. The base metal potential of the area was examined in some detail and found to be significant, particularly for a Lower Proterozoic gossanous formation that occurs throughout southern Baffin Island.

Jan 1, 1977

By J. Pepin

When using alternating current submerged arc welding (SAW) to produce pipes from microalloyed linepipe steels, it is critical to balance penetration depth and deposition rates, in order to minimize the number of weld passes while still maintaining good heat affected zone (HAZ) microstructures and properties. A series of bead-on-plate (BOP) submerged arc welds were performed on X70 steel, using different waveform variable settings (i.e., balance, offset and frequency). Weld bead cross-section profile deposition and penetration areas were measured, and both Vickers hardness and Charpy V-notch impact testing were performed. Both single electrode and tandem electrode welds were evaluated.

Jan 1, 2011

By M. Girard, C. Farsangi, N. Singh

"Canadian Royalties Inc. owns and exploits the Nunavik Nickel Project: a copper and nickel deposit in Nunavik, Québec. The nickel and copper concentrates are filtered by plate and frame filter presses, and are transported 100km north to Deception Bay by truck. As the site is situated in the far north, extreme weather can be detrimental to production: roads can close for significant periods of time, resulting in the concentrator using all its storage capacity. During the winter of 2017, this accounted for over 100 hours of unplanned mill downtime. Different solutions to this problem were evaluated and the most economically viable combination of solutions was determined to be the use of concentrate storage containers and upgrading the plate size of the existing nickel filter press. By satisfying new, increased utility requirements, the cycle times would not change, but produce 30% more filter cake. Simulations were developed to determine the number of concentrate containers needed in conjunction with the upgraded press to eliminate unplanned downtime due to road closures and secure production through the winter. This paper summarises these simulations, the commissioning and start-up of the upgraded filter press, container loading procedures, and how this was put together to achieve a record 2018 winter season with a 90 percent reduction in downtime. The payback period of the project was 4 months. A specialised side-tipping trailer emptied the containers during the fall of 2018.INTRODUCTION The Nunavik Nickel Project is a nickel/copper mining project located in Nunavik, Québec. The nickel and copper concentrates are stored in stock tanks after thickening and are then filtered by plate and frame filter presses at the concentrator before being transported 100km to the shipping port at Deception Bay by trucks. The region is prone to periods of extreme weather during the winter, with winds that can reach +100km/hr and blizzards that severely limit visibility. The roads to Deception Bay are often affected by this weather, causing closures that last an average of 18hrs and as long as 72hrs. Additionally, there is a 15% chance that road closures occur within 24hrs of the last event. This has been an issue for the concentrator team since start-up in 2013, causing unplanned mill downtime every winter (Table 1) due to filling concentrate storage capacity during prolonged closures of the roads to Deception Bay."

Jan 1, 2019

By W. L. Nelson

The orebodies at Copper Mounta1n lie along and within a few hundred feet of the contact of an intrusive stock of gabbro with a series of bedded volcanic rocks of the Nicola formation. These. orebodies are all entirely within the volcanic series but in many cases the centre line of the orebody at depth is directly under the gabbro contact at the surface, due to a slight overhang of the gabbro. The gabbro and volcanic rocks are cut by a number of faults and fault zones which did not materially affect early mining operations, but, as undeground openings increased in size, the faults became more important factors in determining mining methods and procedure. Caving methods were adopted to take advantage of ground weakness in fault zones, and the effect of ground subsidence which resulted from the division of the ground 1nto large, independent blocks by faulting had to be considered in planning the sequence of mining of certain ore blocks. The faults have been divided into two classes: the longitudinal system and the cross faults, or 'breaks' as they are termed locally. In addition to the two classes of faults, the zones of parallel ore fracture also control mining procedure, but to a lesser degree, in regard to caving or ground subsidence. A third structural feature which influences mining procedure is the mine dyke system. The longitudinal or main fault system roughly parallels the gab? bro contact and is made up of a number of branches and auxiliary fractures. The main fault itself is essentially vertical, but there are a number of branches and fractures on each side of it which, though parallel m strike, may dip as flat as 50 degrees toward or away from the main fault. The full width of the main fault system has not been determined, but it is known to extend beyond the zone of mine workings. A marked schistosity follows the main fault and both schistosity and chloritic alteration have been noticed along the secondary faults of this system. Several prominent orebodies lie along the main fault and its branches. The influence of the main fault system on mining is probably related more to subsidence than to actual cavi.ng, although it is effective in both.

Jan 1, 1950

By E. Wolmarans

The selection of the main mineralised zone (MMZ) concentrator milling circuit has followed a comprehensive route over the preceding 10 years. Many knowledgeable parties have contributed and assisted in developing the milling circuit according to the best available information. The final selection of the flow sheet was completed after DRA conducted a techno-economic study on four possible comminution circuits ranging from conventional crushing and ball milling to fully autogenous (AG) milling. The results from all the above mentioned work indicated that it is possible to treat the MMZ ore at the desired throughputs to the desired grind sizes in a fully autogenous grinding circuit. The flow sheet was designed to treat the main mineralised zone (MMZ) arising?s from both underground and open cast operations and incorporates a fully autogenous grinding (AG) circuit. Commissioning of the 375ktpm concentrator at Nkomati Nickel began in August 2009 with the first ore reporting to the mill on the 15th of September 2009.

Jan 1, 2012

By H. A. Khorami, T. Wong, B. Velapatino, E. Asselin, T. Donnelly, E. Bryce, R. Dixon

A copper–nickel concentration gradient alloy was designed and fabricated through a powder metallurgy (PM) process. Copper and nickel powders were mixed with different weight ratios from 0 to 100% copper in 10% increments. Each powder mixture was poured inside a cylindrical die and compacted between two punches using a hydraulic press machine at pressures up to 70 MPa, resulting in approximately 1 mm thick layers (discs) of pressed Cu–Ni powder. These 11 Cu–Ni compacted powder layers, i.e. 0–100% Cu with 10% increments, were then compressed together with pressures up to 420 MPa to form a green part. The green part was sintered in a vacuum furnace at 1000°C for 10 hours to form a solid mass (PM part) of Cu–Ni concentration gradient alloy. In the sintering process, Cu and Ni particles fused together and formed a single piece due to diffusion of the atoms across the boundaries of the particles. The diffusion of atoms also converted the stepwise concentration change into a uniform concentration gradient. INTRODUCTION Copper has numerous applications in different industrial sectors due to its superior physical, electrical, mechanical and chemical properties such as its excellent thermal and electrical conductivity, resistance to fatigue, high ductility, and resistance to corrosion. Moreover, copper and its alloys have natural antimicrobial properties. This has opened up new applications for copper–based self–disinfecting surfaces in healthcare in an effort to mitigate healthcare–associated infections (HAIs). HAIs affect millions of patients each year, leading to significant morbidity and mortality as well as financial losses to healthcare systems (World Health Organization, 2016). HAIs spread through three main routes: (a) iatrogenic in which HAIs are a direct consequence of medical encounters and/or treatment; (b) person to person where organisms are transferred between healthcare workers, patients, and visitors; and (c) environmental where transmission occurs via contaminated surfaces and equipment (e.g. doorknobs, railings, toilets/commodes, medical carts). The use of antimicrobial copper–based materials on high touch surfaces could diminish pathogen transmission via this latter rout. This has subsequently led to the development of a variety of copper–based materials for use in healthcare settings and promoted the investigation of the antimicrobial efficacy of copper–based materials.

Jan 1, 2019

By P. W. A Severin

"The Sturgeon Lake deposit, a partly eroded lens of massive sulphides with an underlying sulphide stringer zone, is one of five orebodies that occur in the Sturgeon Lake area of northwestern Ontario within volcaniclastic rocks of the Archean Wabigoon Subprovince in the Superior Province of the Canadian Shield.The Sturgeon Lake Cu-Zn-Pb-A g-Au deposit was discovered in October 1970 as a result of an I.P. survey. Production from this open-pit mine began in March 1974 and continued until the ore was exhausted in March 1980.The Sturgeon Lake property is underlain by basaltic volcanics, minor amounts of mafic lapilli tuff and rhyolite volcaniclastics. A quartz crystal-bearing rhyolite occurs at the top of the felsic volcaniclastics and is ""capped"" by the Sturgeon Lake massive sulphide deposit. The felsic volcanics have been intruded by a crudely layered sill-like, carbonatized mafic intrusion. Recent work suggests that the felsic rocks that underlie the Sturgeon Lake deposit are lateral equivalents of those in the vicinity of the Mattabi Mine and are not correlative with the dacitic volcaniclastics that underlie the Lyon Lake and Creek Zone deposits. Hydrothermal processes that resulted in the formation of the Sturgeon Lake orebody have resulted in a depletion of Na2O, CaO and FeO and an increase in MgO, K2O, copper and zinc. In the vicinity of the sulphide stringer zone, the rhyolites are ""bleached"" due to silicification and sericitization. The rocks lying immediately below the massive sulphides are locally strongly chloritic.The Sturgeon Lake deposit may have formed on a top ographic high which prevented mafic flows and dacitic volcaniclastics that underlie the Lyon Lake and Creek Zone deposits from inundating the Sturgeon Lake fumarolic vent from the west. Continued or resurgent activity from the Sturgeon Lake fumarole may have resulted in the formation of the Lyon Lake and Creek Zones as more ""distal "" deposits in topographic lows. The Sturgeon Lake, Lyon Lake and Creek Zone deposits were subsequently overlain by mafic tuffs and flows."

Jan 1, 1982

By P. R. Jones

"The paper describes the CDN$400 million expansion at Hudson Bay Mining and Smelting Co., Limited’s operations. The company has continuously produced copper and zinc at the Flin Flon metallurgical plant since 1930. The paper details the company’s operational turnaround since 1995 and “The 777 Project” which includes two new mines, expansion and modification of the concentrators, expansion of the zinc pressure leach plant, a new zinc electrolytic cellhouse and modifications to the copper smelter gas handling system to reduce ground level gas emissions. IntroductionHudson Bay Mining and Smelting Co., Limited (HBMS) was incorporated in 1927 to mine and process the world-class Flin Flon copper and zinc orebody. Ore concentration and metallurgical facilities were constructed in Flin Flon. The metallurgical complex capability is currently 89 000 tonnes of copper metal and 98 000 tonnes of zinc metal from both HBMS and purchased concentrates.Flin Flon, with a population of 7000, is in Manitoba and partly in the province of Saskatchewan. The location is isolated with Winnipeg 800 km to the south and Saskatoon 500 km southwest.Today, three underground mines feed the Flin Flon concentrator, one feeds the Ruttan concentrator at Leaf Rapids, 200 km to the north of Flin Flon, and Chisel North mine feeds the Snow Lake concentrator (Fig. 1).The Flin Flon volcanic massive sulphide proximal and distal orebodies are within the Flin Flon greenstone belt which stretches from the west of Flin Flon to the east of Snow Lake, a distance of 250 km. The belt is approximately 100 km wide before disappearing below the paleozoic cover to the south."

Jan 1, 2001

By Gregg W. Morrison

"The Craigmont copper-iron skarn deposit is adjacent to the southern margin of the late Triassic Guichon Creek batholith in south-central British Columbia. Host to the ore are sedimentary and volcanic rocks of the western calc-alkaline belt of the Upper TriassicNicola Group. In the mine area, the Nicola Group rocks are a stratigraphically complex sequence, at least 1800 feet thick, which have been subdivided into Basalt, Rhyolite, Carbonate and Clastic Sediment units. All the units strike and dip parallel to the margin of the Guichon Creek batholith and are within the batholith contact aureole. However, only the Clastic Sediment unit is in contact with the batholith.Most of the skarn and ore is within the Carbonate unit and more specifically within an Interbedded facies that consists of lime sandstone, lime siltstone, quartzo-feldspathic siltstone and argillite. The Interbedded facies and the adjacent barren Massive Limestonefacies are interpreted aspart ofa carbonate reef complex. The distribution of skarn and ore within the Interbedded facies suggests that the facies boundary was a physical and chemical barrier that resulted in concentration of metals adjacent to the Massive Limestone facies.Two stages of skarn formation have been recognized at Craigmont. In Stage I, ore-bearing magnetite-rich and actinolite-epidote-magnetite skarns developed both in basaltic rocks and in Fe-bearing siltstone and argillite of the Interbedded facies, while barren grossular garnet-epidote-calcite-pyrite skarns developed in Fe-poor rhyolitic bands within the Interbedded and Massive Limestone facies . In Stage ll, massive, barren grandite garnet skarn replaced mineralized Stage I skarns in the vicinity of diorite plugs. and specularite ore formed in brecciated Stage I skarn and clastic rocks away from the plugs. Theformation of Stage I skarns required no addition of material, only redistribution and concentration of elements already present within the Interbedded facies. However, the concentration of Cu in Stage lore requires a mechanism for more efficient leaching of Cu from the host rocks, an anomalous concentration of Cu at the site of the Stage I orebody or an additional input of Cu from an external source. The formation of Stage II skarn and ore requires only remobilization and recrystallization of Stage I skarn and ore.Copper and iron are the only elements in economic concentrations in the ore and chalcopyrite is the only significant copper-bearing mineral. Chalcopyrite is disseminated and interstitial to magnetite in Stage I mineralized skarns and is interstitial to specularite in the matrix of Stage II breccia ores. Chalcopyrite also occurs with pyrite as stringer ore in bleached • sediments and rhyolite tuffs in the stratigraphic footwall of the main orebodies.The Craigmont deposit has more features in common with Cu-Fe deposits hosted in metavolcanic and metasedimentary rocks than it has with typical skarn deposits associated with porphyry copper deposits. The orebody is more likely a product of concentration of metal contained within the Nicola Group rocks than of the mineralizing event that produced the . Highland Valley Cu-Mo porphyry deposits in the central part of the Guichon Creek batholith ."

Jan 1, 1980

By J. R. Levin, E. J. Schelter

"We present some of our recent efforts in the development of predictive, directed oxidation chemistry of cerium(III) complexes under non-aqueous conditions. The electrochemistry of cerium(III)- alkali metal heterobimetallic aryloxide complexes is reported and compared with cerium aryloxide complexes that are kinetically stabilized by hydrogen bonding cations that span between the complexed aryloxide ligands. Comparative electrochemical measurements reveal differences between the heterobimetallic complexes and the hydrogen-bonded complexes.INTRODUCTIONThe rare earth elements comprise the lanthanides, La–Lu, and the element yttrium (Aspinall, 2001). Rare earth ores such as monazite, LnPO4, and bastnäsite, LnFCO3, typically bear mixtures of light rare earths: La–Sm while monazite, LnPO4, contains mixtures of heavy rare earths (Eu–Lu) (Cotton, 2006). Pure rare earth elements typically are isolated using a liquid-liquid separations process.(Bautista, 1995) The hydrometallurgy of these elements is a difficult problem because the separation factors between neighboring rare earths, which are predicated on the small differences in the sizes of the trivalent ions, are quite small (Cox, 1992). The element cerium, with its 4f1 electronic configuration in the trivalent state, is unique among the rare earth elements due to a relatively accessible 4f0 electronic configuration. The accessibility of the 4f0 configuration underlies the chemistry of cerium(IV), the only rare earth ion with molecular chemistry in the tetravalent oxidation state (Cotton, 2006). Cerium is trivially separated from mixtures of light rare earths by making use of its unique oxidation chemistry. In an effort to extend separations chemistry by oxidation reactions to other rare earth elements such as terbium and praseodymium, the solution electrochemistry of well-defined cerium complexes is of interest."

Jan 1, 2012

By F. L. Casey

"Part 1 – Published Papers Baria, G., and Boshkov, S., ""Insights into Undercuttingin Block Caving"", Proc. 5th Rock Mech. Symp.,Mines Br. - Information Canada, 41-58, 1970.Barron, K., Coates, D. F., and Gyenge, M., ""ArtificialSupport of Rock Slopes'', Mines Branch ResearchReport R228, July, 1970.Barron, K., ""Criteria for Brittle Fracture Initiation inand Ultimate Failure of Rocks and Their Applicationto Fracture Zone Prediction"", Proc. 2ndCongr. Int. Soc. Rock Mech., Belgrade, 1970, 3-37.Bauer, A., and Calder, P. N., ""Projectile Penetration inRock"", Proc. 5th Rocle Mech. Symp., Mines Br. -Information Canada, 157-170, 1970.Bauer, A. M., ""Site Development and Rehabilitation ofPits and Quarries"", Canadian Mining Journal,Vol. 91, No. 7, 77, July, 1970."

Jan 1, 1971

By F. Sorensen

ABSTRACT Electricity production by the Electricity Supply Commission of South Africa (Eskom) is the most important beneficiation process for South African coal. As one of the world’s lowest cost producers, energy-intensive industries such as ferroalloys and aluminium were introduced. However the poor were neglected. The white paper on energy policy (Department of Minerals and Energy, 1998) sought to redress this. Also, chasing economic growth to generate jobs resulted in high electricity demand and interruptions. Lifespan estimates of South African coal reserves based upon peak theory vary widely. Approaching peak, coal production in the future will be more expensive and, thus, contribute to more expensive electricity, which could inhibit industrial development unless South Africans work smarter.

Jan 1, 2011

By G. P. Contractor

Many factors affect the forge ability of steels. One of the major factors is chemical composition.' This article discusses the individual effects of alloying elements and the effect of the resultant modification of microstructure onforgeability. INTRODUCTION T HE use of alloy steels is expanding considerably and the fabrication procedures for such alloys are becoming more complex. An attempt is made in this article to describe the effect of alloying elements on the hot-workability of steels. Most of the data reported here are taken from the studies of Ihrig, Clark and others (Refs. 1-4). Chemical composition is not the only controlling factor. Grain size and surface condition of the material, forging temperature, and speed of deformation are also important. Certain conclusions can be drawn regarding the effect of various alloying elements on the hot-work-ability of forging stock. The results of hot-twist tests are considered useful in this connection as the number of twists to failure has been taken as the level of forgeability at a particular temperature. The peak in the "Number of Twists -Tem--

Jan 1, 1962

By R. K. Collings

Mineral wastes from the mining, metallurgical and chemical processing industries in Canada amount to about 800 million tonnes annually. Such wastes often are largely non-metallic in composition and are of interest for traditional non-metallic mineral uses and applications. Mineral waste disposal and maintenance are costly; furthermore, these wastes may pollute groundwater, rivers and lakes. These factors and an increased appreciation of the potential utility of some mineral wastes have stimulated research in this area.

Jan 1, 1984

By P. J. Urso

"The coal reserves of the Crow's Nest Basin in British Columbia have been known since the late 1860's. The 51.0-million-long-ton (over 15 years) sale of low-volatile coking coal to Japanese steel mills, as finalized in 1968, establishes the importance of these coal reserves in the world markets.In the early stages of the exploration program, which began in January, 1967, emphasis was placed on deter-mining the reserve of underground low-pitch coal within the No. 10 or Balmer seam of the Kootenay coal forma-tion. The finding of low-cover reserves in excess of 100,000,000 tons altered the initially planned underground program. Extensive tests were performed, establishing the excellent coking characteristics of the open-cast Balmer coal. Due recognition was given to the ultimate reclamation costs of mined lands and associated spoil areas.t was determined that, to achieve the costs desired, a high productivity was necessary, requiring large mining equipment. Operating criteria were set out, based on producing 4.2 million tons of clean coal per year. To optimize recovery, the preparation plant feed size was fixed at Yi in. x 0. The initial basic design capacity of the plant was 1,000 tph. The washing plant is composed essentially of four separate cleaning sections: a dedusting section; a multi-stage heavy media cyclone section; water cyclones; and flotation cells. Subsequent to the basic program, additional sales were made of 6.0 million long tons over the initial three-year period and the plant capacity was raised to 1,400 tph through the addition of a 400-tph coarse-coal treatment section. All wet coal products from the fine coal plant will be dried in a 70-tph (water) heat dryer. A unit-train concept of coal transportation between the mine site and the Westward Terminals at Roberts Bank has been negotiated with the Canadian Pacific Railroad. Facilities at the port will include a 4,000-tph rotary car bumper, 400,000-ton clean-coal stockpiles, and a bucket reclaiming system having a total ship-loading capacity of 6,000 tph."

Jan 1, 1969