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By Kendrick C. Hardcastle

Although the basic techniques employed in hydraulic pumping in open pit mining have been practiced throughout the better part of this century, only relatively recently have studies of' sufficient depth and scope been conducted to improve these techniques. This paper will point out the basic techniques involved and some of the more recently discovered data concerning hydraulic pumping, Inherent in all hydraulic transportation systems apart from the consideration of transportation cast, is the outstanding advantage of slurrying the matrix at the mining pit so as to provide a lengthy and thorough soaking and washing of the material while in the pipe line and thereby reduce the necessity for washing, scrubbing and other treatment in the beneficiation plant. This is quite important in view of the constant increase in demand for a cleaner product.

Jan 1, 1964

By Yutaka Shiraishi

Two methods were developed to measure the viscosity of the slag from the glassy to the liquid states in an ascending temperature process. The first method employs rotating parallel plates within which is placed a solid cylindrical sample in line with a sphere. The second method uses a tube which is pushed into a sample held in a rotating crucible. Both methods were tested using standard glasses, including boron trioxide and NBS standard glass #711. The main difference between these two methods is in sample preparation. Comparative measurements between two methods were performed using a sodium boro-disilicate glass containing 5%mol of alumina. The results showed good agreement in the mid-range of glassy viscosities, 105 to to7 Pa.s. In the liquid state, there were no significant differences between the two methods.

Jan 1, 2003

By J. Guha, R. Kanwar, G. Archambault, A. Tremblay

The Copper Rand Cu-Au deposit lies within a shear zone which strikes N50-60W and dips steeply southward (50°-55°) and extends over 1. 5 km with a thickness which varies form 350 to 425 metres. Mineralization, inside the shear zone, is structurally controlled by a dilation mechanism which can be explained by a fracture dilatancy model. The principle of this model involves the mechanics of overriding of irregular planes and surfaces of faults and schistosities, These structures are characteristic features of the Copper Rand shear zone. A structural analysis of the shear zone has been carried out to establish relations between the different structures within the shear zone and their evolution with the development of the shear zone. A geomechanical interpretation of the Copper Rand shear zone explains the formation of internal structures such as faults, schistosities and microstructure during the shearing. This interpretation confirms Ramsay's theoretical model on the geomechanical evolutuion of shear zone development, and the experimental work of Morgenstern-Tchalenko on the simulation of shear zones in clay models. The geomechanical interpretation of the shear zone demonstrates that at the onset, subsidiary fracture patterns are developed in second order faults in the following sequence. At peak strength Riedel shears ( R and R') are formed which propagate outside the strength, restraint (P) shears are developed in the thrust attitude within the shear zones. Principal displacement shears (D) develop toward residual strength in the direction of movement. Shear lenses are formed by the interaction of these shear discontinuities and these facilitate the formation of schis tosi ties with the continuation of the shear displacement within the main shear zone. While the main shear zone and the P and D shears within the main shear zone were in continual movement, the Rand R' structures, once formed, retained a simple fracture pattern and moved little outside the shear limits in comparison to the main shear zone. Parts of these structures inside the shear zone were reactivated by subsequent movements and deformed into folds to account for the present attitudes of the HW-1 and HW-2 and HW-3 structures. This geomechanical model for the shear zone with its subsidiary structures (R, R', P and D shears) is also applied on a larger scale to the Dore Lake shear belt and explains the different structures accompanying it. The initial development of the WNW shears (most are ore deposits) was followed by the subsidiary structures of the Dore Lake shear in a north-south stress field and is well defined by the movements characteristic of the different structures. It is concluded that the Dore Lake shear cannot be the prolongation of the McKenzie Narrows shear but it seems that this prolongation relates to the Henderson-Portage shear zone.

Jan 1, 1984

By Ferit Gurses

Extensive coal and lignite deposits exist in Turkey. Bituminous coal is the nation's principal mineral resource; important not only as fuel for the industrial development of the country, but also as a means of obtaining foreign exchange. Of the electrical power generated during 1939, 82.8 per cent was derived from coal.' It is anticipated that the lignite deposits will be one of the major sources of power for the electrification of the country. Bituminous Coal The locations of the four principal bituminous-coal2 basins are indicated on Fig. 1. The Eregli-Zonguldak basin lies on the Black Sea northwest of Ankara; the Canakkale basin lies near the junction of the Dardannelles; the Trakya basin is in European Turkey northwest of the Bosphorus and the Erzurum basin lies far to the east. The Eregli-Zonguldak basin is the most important of the four. This coal basin was discovered in 1829 but did not arouse interest until 1848; up to 1865, its annual production had not exceeded 50,000 metric tons. In 1865, during the Sultanate, working of coal mines was started by the Navy department, and the annual production was 61,145 metric tons. In 1908, the Minister of Commerce and Agriculture was authorized to develop the whole coal basin. Production reached 264,397 metric tons in 1910, and during 1915-1922, preceding the revolution, the total produc- tion of the basin was' 2,676,043, or an average of 334,000 metric tons annually. The period of national revolution that followed was marked by a steady increase in coal production in Turkey, although world production decreased, because of the crisis of 1929-1932, about 52 per cent. ARea and Geology of the Coal Basin The geology of the Eregli-Zonguldak area is not yet completely known. The basin begins -at Gungazi, to the west of Eregli, and extends to Sogutozu, a distance of about 106 miles. The coal beds, however, appear only in places and the overlying Cretaceous strata hide them elsewhere. This area includes the most important centers, such as Kandilli, Alacaagzi, Teflenli, Kozlu, Gelik (see Fig. 2). The geological sequence of the district is correlated with the Cretaceous of the Balkans; which is, in turn, a prolongation of the Alpine zone. Geological surveys made by G. Ralli, R. Zeiller and P. Arni3 show that the Eregli-Zonguldak formations fall into three natural divisions. Series a, The Alacaagzi in the district of that name (Fig. 2), is of the Culm stage. The strata strike generally east-west and dip about 30" south. This series appears also around Kandilli and Camli, with a steeper angle of dip, but the deposits there lack regularity. The Alacaagzi stage appears also farther east, to the south of Kozlu and Gelik. The Alacaagzi series contains 15 seams of an average thickness of 2 ft. of good coal. Series b, the Kozlu, best represented in Zonguldak, Kilimli, Catalagzi, and between

Jan 1, 1944

By Ferit Gurses

Extensive coal and lignite deposits exist in Turkey. Bituminous coal is the nation's principal mineral resource; important not only as fuel for the industrial development of the country, but also as a means of obtaining foreign exchange. Of the electrical power generated during 1939, 82.8 per cent was derived from coal.' It is anticipated that the lignite deposits will be one of the major sources of power for the electrification of the country. Bituminous Coal The locations of the four principal bituminous-coal2 basins are indicated on Fig. 1. The Eregli-Zonguldak basin lies on the Black Sea northwest of Ankara; the Canakkale basin lies near the junction of the Dardannelles; the Trakya basin is in European Turkey northwest of the Bosphorus and the Erzurum basin lies far to the east. The Eregli-Zonguldak basin is the most important of the four. This coal basin was discovered in 1829 but did not arouse interest until 1848; up to 1865, its annual production had not exceeded 50,000 metric tons. In 1865, during the Sultanate, working of coal mines was started by the Navy department, and the annual production was 61,145 metric tons. In 1908, the Minister of Commerce and Agriculture was authorized to develop the whole coal basin. Production reached 264,397 metric tons in 1910, and during 1915-1922, preceding the revolution, the total produc- tion of the basin was' 2,676,043, or an average of 334,000 metric tons annually. The period of national revolution that followed was marked by a steady increase in coal production in Turkey, although world production decreased, because of the crisis of 1929-1932, about 52 per cent. ARea and Geology of the Coal Basin The geology of the Eregli-Zonguldak area is not yet completely known. The basin begins -at Gungazi, to the west of Eregli, and extends to Sogutozu, a distance of about 106 miles. The coal beds, however, appear only in places and the overlying Cretaceous strata hide them elsewhere. This area includes the most important centers, such as Kandilli, Alacaagzi, Teflenli, Kozlu, Gelik (see Fig. 2). The geological sequence of the district is correlated with the Cretaceous of the Balkans; which is, in turn, a prolongation of the Alpine zone. Geological surveys made by G. Ralli, R. Zeiller and P. Arni3 show that the Eregli-Zonguldak formations fall into three natural divisions. Series a, The Alacaagzi in the district of that name (Fig. 2), is of the Culm stage. The strata strike generally east-west and dip about 30" south. This series appears also around Kandilli and Camli, with a steeper angle of dip, but the deposits there lack regularity. The Alacaagzi stage appears also farther east, to the south of Kozlu and Gelik. The Alacaagzi series contains 15 seams of an average thickness of 2 ft. of good coal. Series b, the Kozlu, best represented in Zonguldak, Kilimli, Catalagzi, and between

Jan 1, 1944

By R. August Heindl

A process for recovering manganese from open-hearth steel-plant slags was investigated. The proposed method of accomplishing this is indicated by the flow diagram in figure 1. Mixtures of open-hearth, steel-plant flush slags and limestone, so proportioned as to have molar [CaO -3P205] ratios of approximately 2, were fired at approximately 2,400° F. in an oxidizing atmosphere and then cooled slowly. This treatment produced a clinker consisting principally of two solid phases comprised of (1) various combinations of the oxides of manganese, iron, aluminum, and magnesium, probably in spinel complexes, and (2) a dicalcium silicate phase, which contains the phosphorus. Reduction of these clinkers with hydrogen or with gaseous mixtures containing CO, CH4, and other hydrocarbons at about 1,300° F. formed manganous oxide as well as varying amounts of ferrous oxide and iron. Carbon monoxide and mixtures of hydrogen and carbon monoxide effectively reduced the clinkers but also gave higher proportions of soluble iron when the manganese was extracted from the reduced clinkers by leaching at about 80° F. with ammonium carbonate solutions containing 26 to 28 percent ammonia and 15 to 26 percent carbon dioxide. It is believed that the manganese is in solution as an ammonia-manganese complex. Concentrations of about 90 grams of manganese per liter were obtained by batch countercurrent procedures. By distilling 50 percent of the ammonia, the ammonia-manganese complex was decomposed, and approximately 90 percent of the manganese was precipitated as the carbonate with the simultaneous precipitation of 15 to 30 percent of the iron, the larger amounts of iron precipitating in the continuous tests. The manganese-iron ratio in the product could be increased either by recycling more manganese from the distillation to the extraction or by aerating the liquor to purge it of iron before, rather than after, the distillation step. Calcination of the pelletized manganese carbonate in an oxidizing stmosphere at 2,000° F. or above gave a final product, Mn304, resistant to crushing and apparently possessing the other physical properties essential in a ferromanganese blast-furnace feed.

Jan 1, 1955

By Jean Habimana

The Detroit Upper Rouge Tunnel CSO Control Project will capture and store up to 201 MG of combined sewer overflow from 28 outfalls in Detroit, Dearborn Heights and Redford Township during wet-weather events. The history of rock tunneling in the area is associated with high groundwater inflows, artesian pressure, and hazardous and combustible gases. This paper presents the geotechnical considerations for designing the 11.28-km (7-mile) long, 9.14 m (30-ft) finished diameter tunnel and its associated adits, chambers and shafts, including the discussions of geotechnical investigations, rock mass characterization, estimated groundwater infiltration during construction, and the selections of excavation methods and lining system based on anticipated ground behavior to be encountered.

Jan 1, 2008

By Doris M. Hyde

In the past, mining has represented between 11% and 12% of the gross domestic product (GDP). In 1982, mining contributed over $150 million to the estimated $1.4 billion GDP.2 Overall economic growth for 1983 was projected at about 2%, primarily as a result of increased tourism. The inflation rate remained at or fell below the 1982 level of almost 4%. The Government continued its efforts to strengthen the industrial base by improving infrastructural systems and the establishment of a free trade zone. Laws against property ownership by foreigners or foreign-owned companies were strengthened, but the prohibition was softened to allow for close family inheritance. Otherwise, Government approval must be obtained to retain property acquired through inheritance, court order, mortgage, or other means. Special consideration was granted to foreign investors seeking to promote industries beneficial to the economy.

Jan 1, 1985

By W. M. Weigel

SALT production in Louisiana and Texas at the present time is entirely from salt domes of the interior and coastal groups. Before and during the Civil War salt was recovered from numerous salines and salt springs by evaporation in open 'kettles. The location of these in nearly every instance was near what is now known to be a salt dome, and the source of the salt in the salines and spring waters was that in the salt core. The tops of many of the shallower domes have been subjected to erosion1. The discovery that the salt occurred as large masses of rock salt in the form of domes was made in May, 1802, at Avery Island, La., by John Marsh Avery, grandson of the original owner, John C. Marsh, who built the old salt works in 18122. The first shaft for mining was sunk on the Avery dome in 1867 by Chouteau and Price. It was 90 ft. deep, about 58 ft. being in solid salt. It was abandoned in 1870. There are three general groups or fields of salt domes; interior Louisiana in northern Louisiana, interior Texas in northeastern Texas, and the coastal domes nearer the Gulf Coast and extending from the Mississippi River to the Rio Grande. This last group contains by far the greatest number of domes. As many of the coastal domes especially are prolific producers of petroleum and a few of sulfur, their geology has been intensively studied and fully covered in the literature. The depth to the top of the salt varies from near the surface, where shallow ground waters have dissolved the salt to just below recent deposits, to several thousand feet, where the depth has been estimated only by geophysical methods. The diameter of the salt core varies from less than ½ mile to over 2 miles. Only domes where the salt is compara-tively near the surface have been developed for commercial salt. Three deeper domes, which will be described later, have recently been developed or are in process of development, as a source of brine for chemical use.

Jan 1, 1935

By R. D. Leitch

The work of the United States Bureau of Mines on stream pollution3 by coal-mine drainage has included a study of seasonal variations in acidity and volume of several streams in Pennsylvania. The acidity of these streams has been determined during the two or three years prior to 1930 and the results may be considered to represent "normal" low water conditions. The summer of 1930, however, was unusually dry and represents what may be termed "extreme" low water conditions on these streams. This report is a comparison of the results obtained for extreme low water of 1930 and for other years. The streams investigated were Buffalo Creek in Somerset County, Indian Creek (lower 5 miles) in Westmoreland County, Little Toby Creek in Elk and Jefferson Counties, Daguscahonda Run in Elk County and West Creek in Elk and Cameron Counties. These will be treated separately in the order given. Most of the descriptive matter and physical data pertinent to the streams and drainage basins are taken from published reports of the Pennsylvania State Water Supply Commission, 1917.4

Jan 1, 1931

By R deMoraes, A Bobet

The last decade has seen a resurgence of interest in lunar exploration and the emergence of countries like China and India as space fairing nations. In 2004, the US announced a new Vision for Space Exploration, whose objectives focused on human missions to the Moon and then Mars. The near future is likely to see the emergence of a worldwide drive to revisit the Moon as the first step in investigating the Solar System. To date, the Apollo missions provide our only experience of human operations on the Moon or anywhere else beyond Low Earth Orbit. Much was learned from these missions. However, their short duration means that many of the environmental effects that will be important for longer-duration missions could not be quantified. In addition, long-duration missions and infrastructure on the Moon require new technologies and capabilities, which must operate successfully and reliably in this lunar environment. Developing these technologies poses significant challenges for the exploration program. The paper discusses the risks associated with the construction of lunar surface and underground structures and the challenges to adopting the standards and rock mass classification systems developed on Earth and their applicability to the Moon. Moreover, an exchange of views to explore near-surface geologic and geotechnical profiles of the Moon is emphasized and implications of the lack of knowledge on rock mass characterisation of the Moonrock mass, the lack of theoretical/empirical experience on the use of rock mass systems outside Earth, and uncertainties.

Nov 29, 2022

Gold deposits in Eastern China have characteristic of belted distribution. The concentrating belts of gold mineralization are about parallel to the island are belt in Western Pacific Ocean. Gold deposits are mainly concentrated in the aged metamorphic rock series on the upwarping zones and upwarping fault zones, and obviously controlled by the deep fractures and their deriva-tive secondary faults. Gold mineralization had genetic relation to the Mesozoic (especially Yanshan period) magmatic activity. The distribution and genesis of gold deposits can be explained by the assumption of wavy structure. The formation of wavy structure is related to the process of Pacific plate and India plate.

Jan 1, 1990

By Richard J. Robbins

Mechanical raise and tunnel boring are new techniques to most of the mining industry. Coal, salt and potash have been bored economically, but until recently boring machines were not designed specifically for rock boring in underground mining. The construction industry has led the field of rock boring since 1854 when the first tunnel boring machines built by James S. Robbins and Associates went to work at Oahe Dam, South Dakota. Since that time the company has built boring machines for tunneling through ground conditions varying from cohesionless soil to hard rock, and in diameters ranging from 7 feet to 36 feet 8 inches. It is natural that the construction industry got the jump on mining with the use of mechanical rock boring equipment. Mines have looked for the long range answer to problems of underground excavation and they have chosen proved and established techniques they expect to employ for the next ten or twenty years. The mine development was laid out to accommodate these techniques.

Jan 1, 1964

By P. J. Yttrup

Small diameter timber piles are used in Australia to solve foundation problems in soft or filled ground and expansive soil. The paper describes the results of pile load tests to develop simple methods for bearing capacity determination and observation of the performance of piles in expansive soil.

Jan 1, 1989

By J. M. Hassler

Nowhere can there be found a more misleading statement than the old one that "Iron can be manufactured cheaper in the South." During the past decade ironmakers and users of iron have heard varied and sundry stories of the wonderful resources of the Birmingham district, including abundant ore and coal fields, cheap labor, a wonderful climate and similar industrial Utopian statements. Birmingham represents the major portion of the iron business in the South, and as Birmingham fares so goes the iron business of the South. The intent of this paper is to shed some light on the actual conditions surrounding ironmaking in the South, especially in the Birmingham, or North Alabama, district. By a presentation of facts it is desired to point out that the "cheap iron" of the industrial South is a thing of the past, primarily because of increased labor cost and because labor is radically different in performance to what it was years ago. Also, because most of the raw materials needed in ironmaking that would be classed better than inferior are gone. Important Factors The several important factors that have been responsible for this change are : 1. Shrinkage of the iron business in the South. 2. Increased labor cost. 3. The development of the South, with an industrial trend, without a substantial increase of its own iron-consuming market. 4. Increased freight rates, which has narrowed the market that might be reached from this district. 5. Depletion of the better grades of raw materials, both ore and coal. Shrinkage of Iron Business in South.—Table 1 was prepared in early 1936 and revised in 1937, of blast-furnace units in the North Alabama district, considering the year 1936 compared with a maximum number of furnace units of previous years, the peak point being very near the year

Jan 1, 1937

By A. T. Yu

The broken hill proprietary company Ltd., Australia's only steel producer, has come a long way. Since 1885 to reach today's. Capacity of 6.6 million long tons of ingot steel per year.* its Newcastle steel complex in New South Wales, located 100 miles north of Sydney and on-stream since 1915, has likewise shown continued impressive growth (fig. 1). The most recent expansion plans at Newcastle call for sub¬stantially increasing its production, with the help of some added facilities, but principally relying on the increase in efficiency of the furnace operation. Its modern raw materials blending system will playa major role in meeting Newcastle's new targets.

Jan 1, 1969

By M. S. King

"A simple method is proposed for determining the long-term deformation behaviour of evaporites. The theory developed can be tested by measuring the change in diameter as a function of time of a vertical mine shaft opposite evaporite strata. Ultimate shaft closures predicted by the theory agree well with those calculated with the very much more complex theory of Serata (1968), provided that sufficiently high octahedral shear strengths are used in the former.An analysis of measurements made in an isolated opening in a Saskatchewan potash mine shows that the octahedral shear strength of the surrounding potash and halite was approximately 500 psi several years after the opening was mined. This value is less than that deter-mined experimentally for halite by Serata. The same data indicate, furthermore, that the in-situ octahedral shear strength is decreasing slowly with time.The current controversy regarding the actual deformation of evaporites will only be resolved by the cooperation of potash producing companies in releasing data on the long-term deformation of their mine shafts."

Jan 1, 1971

By R. Hurman Eric

The dew-point technique of activity measurements take advantage of the volatility of a component in solution. The pressure of the volatile component over a sample is determined from observations of the temperature at which condensation of the vapor occurs. The method is applicable best when the vapor pressure of the components would differ by about two to three orders of magnitude. Experimentally, this is a closed system involving the use of evacuated and sealed transparent quartz sample probes. Furthermore reliable vapor pressure data of the volatile component is essential along with a specialized high temperature furnace capable of giving reproducible results. In this context, the vertical Dew-Point Furnace (DPF) was designed and built after elaborate trails until enough proficiency was gained for reprodueible results. Over the years the DPF was modified and improved. The DPF developed was versatile and could easily be used for activity measurements in the isopiestic mode (another method of measuring activities of a volatile component in a solution). The necessary ancillary systems; namely evacuation-flushing-evacuation followed by sealing of quartz sample probes under vacuum were also perfected over the years. As and when necessary the dew-point technique was supplemented by classical equilibration-quenching method employed on the sealed quartz sample probes to reveal necessary phase equilibrium information. The following were studied utilizing the above technique: (i) Activities in CuzS-PbS and FeS-PbS binaries and CU2S-FeS- PbS ternary at 1200°C; (ii) Activities in CuzS-SnS and FeS-SnS binaries and Cu2S-FeS-SnS ternary at 1200°C; (iii) Phase equilibria and thennodynamic in Cu-Pb-S, Fe-Pb-S, Fe-Sn-S, Cu-Sn-S and Ag-Sn-S systems. Most recently the following systems have been tackled: (i) Phase equilibria and thennodynamics in the Ag-Pb-S and Sn-Pb-S systems; and (ii) Activities in Ag2S-FeS-CuzS-PbS quaternary at 1200°C.

Jan 1, 2003

By Frank Schrama

Steelmakers worldwide agree that the most efficient and cost-effective solution in BOF steelmaking is to desulfurize the hot metal between the blast furnace and converter. Various methods are currently in use, among which the Kanbara Reactor (KR, using only lime as a reagent), Magnesium mono-injection (MMI, using only magnesium; also known as the Ukraina-Desmag process) and co-injection (using magnesium and lime/CaC2) are leading. These three hot metal desulfurization methods are compared based on metallurgy, efficiency, costs and overall performance. Both available data from literature and experience from Danieli Corus engineers is used for this study. The KR process is able to reach low sulfur concentrations (> 10 ppm) in hot metal and has lower reagent costs. However, due to higher Fe-loss and heavy wear the KR process has the highest operational costs. The Magnesium mono-injection process is very fast due to the use of the reactive magnesium as reagent. Major problems with resulfurization (sulfur levels below 50 ppm cannot be reached) and the violence of the process made that this process could never get a firm foothold in the western steel industry. The co-injection process with magnesium and lime proves to be able to combine the best of both worlds. It can reach low sulfur concentrations and desulfurize fast. Co-injection is also the most flexible and cost effective.

Aug 16, 2017

By A. Wieniewski

The observed progress in technology of non-ferrous ores enrichment and condition of machines and equipment in the ores concentrators on the one hand have brought a possibility and on the other resulted in necessity for introduction of modernization actions. Positive results of investigations into influence of chemical modification of selected products of enrichment process on copper ores enrichment results gave possibility for implementation of chemical-flotation technologies of ores enrichment. The substantial development in flotation machines structure has contributed to modernization of flotation process resulting in increase of enrichment efficiency. The paper presents the idea and results of chemical modification of difficult in enrichment semi-products in the technology of copper ores enrichment and the results obtained after application of the modernised technology. The structure of large-volume flotation machines used in various stages of flotation and current situation in modernization of flotation process in copper ores concentrators are also described. The paper presents industrial-scale results of flotation after application of modified flotation reagents of collector group. Introduction of modifiers into the widely used xanthates resulted in increase of copper recovery in concentrate.

Jan 1, 2014