Tons Of Copper Research Articles

Mineralogy and metal distribution in the copper-tungsten deposit at Ylojarvi, southwest Finland

The Yloejaervi Cu-W deposit in southwest Finland is located at the western end of the Svecokarelidic Tampere schist zone, which consists of argillaceous sediments and volcanics. The deposit was mined from 1942 to 1966. During that time a total of 4,013,500 tons of ore were hoisted, from which 128,343 tons of copper concentrate, 894 tons of scheelite concentrate, and 2,100 tons of arsenopyrite concentrate were produced.The mineralized rock is confined to a tourmaline breccia close to the Haemeenkyroe granodiorite, both some 1,850 m.y. in age. The breccia fragments, which are tuffite and porphyrite, are enveloped by a quartzose alteration seam about 1 cm thick. The matrix is composed of tourmaline with variable amounts of chalcopyrite, arsenopyrite, pyrrhotite, scheelite, and some accessory ore minerals.

The effects of acid rainfall and heavy metal particulates on a boreal Forest ecosystem near the sudbury smelting region of Canada

Sulphur dioxide and particulate pollution have been occurring over a wide area in the Sudbury region, Ontario, as a result of massive smelting operations. In excess of 3Z million short tons of SO2 were released into the atmosphere in the area in 1972, and this pollutant is now discharged through a 1250-foot smokestack. The particulate contribution is an additional complicating and phytotoxic factor. For example, in 1971, 192 tons of nickel, 145 tons of copper, 1130 tons of iron and 4.5 tons of cobalt per 28 days from two of the smelters were released as airborne pollutants (Hutchinson and Whitby, 1974). The natural vegetation of the area is a mixed deciduous boreal forest, with white pine (Pinus strobus), jack pine (Pinus banksiana), red maple (Acer rubrum), red oak (Quercus rubra), etc. as dominant trees. This forest, which previously surrounded the mining town of Sudbury, has been devastated over the past 50 yr, especially by the SO2 emissions and the increased acidity of rainfall and soils. An area in excess of 100 mi2 is now almost devoid of vegetation and damage to the forest vegetation is visible over an area of approximately 1800 mil. The increased stack heights to dilute local pollution problems have spread the problem more widely. The pH of rainfall sampled up to 12 mi east of the smallest smelter in 1970 was less than 4.3 and that within 2 mi of the stacks was frequently of less than pH 3.0. Soil erosion has occurred on a large scale as a consequence of loss of vegetation. Metal accumulation in the soils has also been a complicating and probably highly persistent phenomenon. Concentrations of nickel in excess of 3000 ppm and copper of 2000 ppm in surface soils occur widely. The increased acidity of these soils has increased metal mobility and solubility, presenting phytotoxic problems. The effects on the soil chemistry, especially of organic composition have been profound. They involve an increased metal binding capacity of these soils, and very high levels of sulphur in the purified Tulvic acid′ fraction itself. Indeed, the evidence is suggestive of the incorporation of sulphonic groups into the changed extracts. Such profound and damaging changes may be merely a consequence of the extreme conditions experienced at Sudbury or they may be a harbinger of things to come in many potentially podsolic soils in areas of increasing acidity of rainfall.

Optimization of copper refining

The optimum cd in copper refining is computed along the lines developed in earlier papers, balancing energy against investment cost. The paper discusses the problem of data selection which, among others, arises because a forecast of the future is involved. Depending on the values chosen for the period of amortization, the rate of interest and the energy cost the optimum cd ranges from 0.4 to 1.3 kA/m 2. It is much higher than the cd of 200 A/m 2 used in conventional plants. The savings which could be achieved by operating at the optimum current are considerable. They range from 10–50 $ per ton of copper produced. For most of the conditions envisaged the optimum cd is larger than the limiting cd for natural convection. It can thus be realized only by accelerating the rate of mass transfer. A flow cell is considered in some detail. It is calculated how much energy must be dissipated through friction in order to rise the limiting cds to the values expected to be necessary in order to be able to operate at the optimum cd. It is found that the expenses directly connected with the stirring (power and investment) are a small fraction of the savings attainable. Some other features of a flow system and the modifications in cell design and operation due to the stirring are briefly discussed. The savings would not be drastically reduced even if the use of a flow system should lead to a doubling of the investment as compared to the conventional operation.

Machining of tungsten powder compacts

1. A study was made of the possibility of reusing for subsequent pressing tungsten powder removed by machining from compacts before sintering. 2. The machining of compacts has simplified equipment, increased the coefficient of utilization of tungsten powder from 0.05-0.4 to 0.5–0.7, improved the quality of sintered parts, and reduced the blank sintering and impregnation times. 3. The introduction of machining at only three plants producing tungsten parts has saved about 40 tons of tungsten powder and 4 tons of copper, resulting in an overall annual saving of more than 500,000 rubles.

Future of Oil Exploration Abroad: ABSTRACT

In any consideration of the status of exploration of the oil industry today we are bound to look to history. The industry has always been pursued by the ghost of scarcity one day and the specter of overwhelming surplus the next. Part of this has been due to the sudden opening of new areas for exploration and part of it to the introduction of new methods of exploration, all of which has made available new supplies. Politics also affected the supply of crude. Today we face surpluses in most areas of the world and the problem of these surpluses has afflicted us with a pessimism that has reached into our training schools for geologists and petroleum engineers. Such a mood makes it imperative that we glance at the future. First we must remember that present world proved reserves of oil, producible at present costs, run in the neighborhood of 275 billion barrels, and that there is probably in sight 500 billion barrels. This is in contrast to Pratt's estimate of 77½ billion barrels made 10 years ago. Present world demand is close to 7 billion barrels per annum and is doubling every 11 years. This means that we have proved more than 20 years of supply. These figures would look very different, however, if it were not for the restriction of automotive use in the Communist countries. If all the world consumed oil a the same per capita rate as the United States, the demand would be 50 billion barrels a year and we would have about 5 years of supply in sight. We should, therefore, in our long-run interest keep on looking. This raises the question of how well we have explored the world. It is probably a maxim that every generation believes it knows the limit of world resources. This is largely self-delusion. The next barrel of oil (or ton of copper, if you prefer) is always the hardest to find. But ingenious minds develop new methods which are successful, or bold spirits invade new areas. We drill deeper holes, we refine our means of gathering data. We venture End_Page 263------------------------------ to sea and we today have no idea of the limit to which those explorations will carry us. Three maps are presented showing prospective areas of the world: first one, dated 1944, was prepared by the foreign division of P.A.W.; second one is from Geography of Petroleum, 1950, by Wallace Pratt and Dorothy Good; third one is speaker's own interpretation of the data available today. The first conclusion from all this is that the exploration of the world has just begun. The second conclusion is that instead of slackening our geological, geophysical, and engineering programs, we shall be wise to increase them and to develop wider and better training programs with particular emphasis on technical excellence. End_of_Article - Last_Page 264------------

Alteration associated with ore at Gaspe copper mines [Quebec

The geology of the copper deposits now being developed by Gaspe Copper Mines in the Gaspe Peninsula is summarized in this paper with attention restricted to metamorphism in the host rocks associated with ore replacement. The ore occurs in faulted and gently folded Palaeozoic sediments and seems derived from a buried stock of granite. The best ore-body is a replacement in a limestone bed and lies up-dip from the intrusive. The deeper end of this limestone ore approaches within half a mile of the granite and the upper end is one and one-quarter miles away, with the ore confined to an area of lime-silicate alteration. More siliceous sediments above and below the limestone bed have been bleached and silicified over a two-square mile area. All known ore deposits in these rocks are within the altered zone. The chemical changes accompanying hydrothermal alteration in these ore horizons, which were originally different in composition, are compared. In each case a marked net gain in silica and a corresponding loss in lime is indicated. Quantitatively some 500 tons of silica seem to have been deposited in the host rocks for every ton of copper. In rocks low in calcite, the silicification is widespread and is not a specific guide to the location of ore within the zone of alteration. In limestone rocks alteration is less widespread and is a useful guide in locating ore.

Modern Electric-Power-Distribution Ideas as Applied in a Large War Plant

It may be concluded, without reservation, that the application of load-center distribution principles as herein described was responsible for an amazing reduction in material investment, principally copper and steel, compared with that which would have been required by power-distribution methods employed only a short time ago. In the planning of this project, the greatest emphasis constantly was placed on conservation of materials. The use of compact, repetitively manufactured metal-clad, load-center unit substations do realize good economy in materials and man-hours, and at the same time incorporate simplicity and safety. Unusual features incorporated in this system, which in themselves are responsible for large savings in material, manhours, or both, include: 1. The application of forced-oil air-pressure cooling to the main incoming service transformers. 2. The use of overhead high-voltage feeder-cable troughs. 3. The use of spaced single-conductor low-voltage feeder design with moderate unit copper cross sections. 4. The use of 265-volt fluorescent lighting in combination with common load-center unit substations for serving power and light. (This feature alone accounts for a saving of five tons of copper and ten tons of steel compared with the most economical method of applying 120-volt fluorescent lighting. The secondary selective system design offers a well-balanced combination of simplicity and service reliability. The negotiation of the entire distribution system as a single unit proved highly beneficial in reducing the time of execution and insuring the best co-ordination between the several component portions.

Modern Electric Locomotives in Open-Pit Mine Haulage

Early in 1942 Phelps Dodge Corporation started production of copper from their new open-pit mine and reduction plant at Morenci, Ariz. One of the earliest mining districts of the state, Morenci had produced some 900,000 tons of copper since the beginning of operations in the early 70's, largely from ores of two to three per cent copper content, mined underground.

Modern electric locomotives in open-pit mine haulage

Early in 1942 Phelps Dodge Corporation started production of copper from their new open-pit mine and reduction plant at Morenci, Ariz. One of the earliest mining districts of the state, Morenci had produced some 900,000 tons of copper since the beginning of operations in the early 70's, largely from ores of two to three per cent copper content, mined underground.

The Copper Industry in 1931

W HEN the I930 balance sheets of the leading copper companies of the Western Hemisphere appeared in I93I, it was evident that with certain significant exceptions these companies could, if they chose, go on for some time producing copper at then &rrent rates, sell most of it for less than total true cost, if need be, and stock the rest, without worrying unduly about working capital. This, most of them did for a time. The rest of the world's producers, for one reason or another, also generally went on producing copper at previous rates. The consumers of copper finally chose to stop, look, and listen. Six-and-a-quarter cent copper was one result. Excess world stocks of refined copper at the yearend, amounting to at least 500,000 tons, were another. A third consequence was the series of intercontinental conferences and conversations which lasted from early autumn until the second half of December and brought about further cuts in production. There was, to be sure, substantial curtailment of output in the United States in I93i, as compared with I930. It amounted to about I90,000 tons out of a total world curtailment of approximately 250,000 tons. The major part of the domestic decline was accounted for merely by the fact that production during the first half of I93I was about on a level with that of December I930, when output was well below the average for the other eleven months of that year. Further curtailment including that resulting from the shutdown of the United Verde property in May -occurred in the second half of I93I. Elsewhere in the world, changes were relatively small. The American Bureau of Metal Statistics was forced in October to discontinue the publication of its regular monthly statistics. The data of the Bureau of Mines of the Department of Commerce indicate smelter production in the United States from domestic ores of about 525,000 tons of copper. This figure, in conjunction with the American Bureau's figures for the first nine months of I93I, points to domestic mine output of about 500,000 to 5I0,000 tons, as compared with 69o,ooo to 700,000 tons in I930. Domestic outpuit was just about one-third of total world production of approximately I,500,000 tons. The latter figure, as has been said, represents a decline of some 250,000 tons from the I930 total of I,750,000 tons. In I93I, therefore, curtailment by United States mines accounted for 75 to 8o per cent of world curtailment, a rather smaller ratio than in I930. Curtailment by Latin-American mines was apparently responsible for the greater part of the 5o,ooo-odd tons reduction outside the United States. Changes elsewhere were quite minor. In Canada, production declined about 4 per cent. In Africa, reductions at some properties were virtually offset by increases at others. In Europe, it is probable that the little curtailment which occurred was principally by Rio Tinto. The I93I world output of I,500,000 tons was less than 30 per cent below the I929 production of approximately 2,I25,000 tons, and was only slightly below the output of I924. World consumption of copper, however whatever it was for the year I93I as a whole -had apparently by the end of the year declined to a level that represented an annual rate not exceeding that of IgIo, or about i,000,ooo tons, and was perhaps below that level. For September, the last month for which figures were made available by the American Bureau of Metal Statistics, there was an increase of more than 24,000 tons in the stocks of refined copper in the yards of refineries in the Western Hemisphere. Doubtless stocks increased elsewhere, also. Since there was a world output of blister copper that month of around I20,000 tons, September shipments to consumers at an annual rate between i,000,ooo and i,I00,ooo tons were indicated. There is good reason for believing that in the last quarter of the year both takings and consumption were below, rather than above, the September figure. Output, however, apparently continued at about previous rates, so that stocks of refined copper in WesternHemisphere refineries at the end of I93I may have been as high as 55o,ooo tons, in addition to stocks in the Eastern Hemisphere. It is therefore conservative to say that excess stocks of at least 5oo,ooo tons of refined copper existed in the world at the close of last year.

The Recent History of the Copper Trade

DURING I923 the average price of refined copper in New York was lower than it had been in I9I3, whilst general prices, as shown by the index number of the Bureau of Labour, were 54 per cent. higher. This fact seems to require the more explanation when one considers the great expansion in the use of electricity which has taken place since I9I3, and the importance of copper as a raw material in the electric industry. This explanation may be found in the history of the metal in the post-war years, and in the following pages I have given an account of the course of the copper market since I9I8, and have then attempted to set forth the factors which bear upon the future of the industry. A few introductoryparagraphsprecedethis account, dealing with the sources of supply and the nature of the market considered. The following table shows the copper production of various countries since I9I3. It exemplifies the predominant part played by North and South America in this production, for these countries produced in I9I3, 73 per cent., and in I922, 78 per cent. of the world's total output. The quantities produced by other countries are small in amount and their variations have been of little importance during the period under review, the expansion in production since I9I3 being due almost entirely to variations in the American supply. The only source of supply outside America which seems likely to have an appreciable effect on the market in the near future, is the Katanga region in the Belgian Congo, where resources are being rapidly developed and it is hoped eventually to produce I78,000 tons of copper annually. But at the moment the output of the area is comparatively small, so that any study of the past four years may confine itself, in considering the conditions of supply, to the production of North and South America. Consequently, in the pages which follow, costs and methods of production refer to these countries only, and it is mainly the New York market which is considered. In the American Continent itself it is necessary to note the growing importance of Chile in the production of copper. The resources of this country (which in I9I3 produced 4I,000 tons of ore) have been rapidly developed during recent years, the development having been largely facilitated by low costs of production.,

COPPER RESOURCES OF JAPAN

The production of copper and copper ores in 1921 amounted 57, 597 metric tons and 1, 244, 657 tons respectively, as against 69, 346 tons and 1, 602, 582 to: is in 19-0, a decrease of 11, 749 tons of copper and 57, 925 tons of copper ores. Miues yielding above 250 tons of copper or 10, 000 tons of copper ores, the deposits of which are here to be considered, are shown in the following table, together with their outprits: (unit in metrictons).

Copper Deposits of Arizona

A VERY complete and highly interesting monograph on the copper deposits of Ray and Miami, Arizona, by Mr. F. L. Ransome has just been issued by "the United States Geological Survey as Professional Paper 115. These ore-bodies have rapidly attained first-class importance among the great copper producers of the United States. For a good many years, dating back to 1880, work had been carried on in this district, the small richer veins being worked and a fair amount of copper won, but these deposits were not of a permanent character. About 1905 the attention of mining men was directed to the low-grade disseminated ore of the region, and work on this commenced about 1911. Up to 1918 nearly 46,000,000 tons of this ore had been mined and 490,000 tons of copper produced. The reserves in one group of these mines, that of the Ray Consolidated Copper Co., were estimated in 1916 as more than 93,000,000 tons, averaging 2.03 per cent, of copper; those in the Miami mines at 50,000,000 tons, averaging 1.6 per cent.; and those in the Inspiration mine at 97,000,000 tons, carrying 1.63 per cent. The ore-bodies are large, irregular, flat-lying masses, and consist partly of Final schist and partly of granite and monzonite porphyry, carrying disseminated copper-ore, some being more or less uniformly distributed through the rock and some concentrated in threads or veinlets. The copper occurs principally as chalco-cite, Aough chalcopyrite is also met with. The ore-deposits have apparently been formed by a process of secondary enrichment upon rock that contained relatively little copper. The latter is termed by the author “protore,” and apparently contained from 0.4 to 0.8 per cent, of copper. This “protore”appears to have been formed by the action of thermal alkaline sulphide waters carrying copper in solution, and there is considerable evidence that the presence of great bodies of monzonite porphyry lying far deeper than the present ore-bodies were in some way connected with the presence of these hypogene solutions.