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By Basil B. Zavoico

CRUDE oil production in the United States during 1938 reached approximately 1,214,355,000 barrels, an average of 3,327,000 barrels per day, or 5 per cent below the 1937 record output of 1,279,160,000 barrels. The decreased production did not prevent the stocks of all products from increasing to a total of 575,954,000 barrels by Sept. 30, an increase of 10,957,000 above the total on Jan. 1, or an average daily storage increase in all products of 40,135 barrels. The increase in total stocks was made entirely in the refined products, stocks of crude oil during the first nine months of 1938 having actually declined 7,155,000 barrels to 299,671,000 barrels, or an average daily decline of 26,209 barrels. The 1937 reversal of the preceding five-year trend of discoveries totalling less than withdrawals was continued through 1938 with indicated reserve addition from both new discoveries and extensions considerably in excess of the

Jan 1, 1939

By M. I. Freeman

This paper point put if the companies will considerate large- scale mining in South Américan in the future. In this sense, the philosophy of an international mining company means that the company and the country working in the partnership and they can convince the outside world of the creditworthiness of the project. The mining company would be considering the account metal requirement in the future, the code of behaviour, the obligations and the rights among the employees, the shareholders, the customers, and to the State in wich its work. However, is not specially tailored philosophy for South America. The most important is the satisfactory agreement can be reached even with governments whose domestic laws preclude equity participation by the mining company.

Nov 20, 1969

By Paul M. Tyler

THE farmer pays the phosphate miner! Phosphorus is used in fireworks; goes to battle in military smoke screens, incendiary shells, and tracer bullets; and, in vermin destroying pastes, does its part in the war against insects. A lemon phosphate can be had for a nickel at most soda fountains, and tens of thousands of tons of phosphate rock are mined annually for use in the food industries, chiefly for making monocaleium phosphate baking powder. Sodium phosphate cleaning, washing, and scouring compounds consume substantial quantities: the iron and steel industries buy a few thousand tons yearly to make ferrophosphorus and to balance foundry-iron furnace charges; and even nonferrous metallurgists use a little for phosphor bronze and other alloys. Phosphoric acid, its salts, and diverse other derivatives of this versatile element have countless applications, and industrial outlets are increasing rapidly, especially in the United States. Nevertheless, in this country nearly 90 per cent and in the whole world fully 95 per cent of the phosphate rock consumed is absorbed ultimately in agriculture.

Jan 1, 1938

The Physical Basis of Non-Random Breakage in an Iron-Oxide Ore Hosted Copper Gold Ore

Sep 13, 2010

By J. W. Motter

Currently, virtually all new electric power generation systems under construction are designed with natural gas as the primary fuel. Factors driving these construction decisions involve sustained low prices for natural gas, environ-mental (and consequent regulatory) risks associated with the use of coal for power generation, and relatively high costs of construction for conventional coal-fired power plants. Despite the unarguable abundance of coal in the US. and worldwide, a fundamental question arises: What will be the role of coal in electric power generation in the 21st century? Congress, recognizing the vital and strategic importance of preserving the coal option for electric power generation, authorized the Clean Coal Technology Program. This pro-gram, with original funding in excess of $2,500 million, is intended to promote the demonstration and commercialization of a new generation of clean, efficient coal-based energy technologies through collaboration and partnering with private industry. The two technologies being demonstrated under this program which are the key to the continued use of this nation's huge coal reserves are coal gasification and the pressurized fluid bed. Either or both of these technologies, coupled with a combined cycle will pro-vide the continuing future coal option, while responding to increasingly more restrictive environmental standards. Recent Congressional budget-cutting efforts, however, could threaten the effectiveness of that model program, and ultimately other subsequent government-industry collaboration.

Jan 1, 1996

By Harvey N. Davis

MUCH has been written and said during the last twenty years about the place of the engineer in modern life, about the fundamental role that he plays both in developing and in maintaining the material foundations of modern civilization, about the advantages, and also the dangers, of the machine age that he has inaugurated, about the Frankenstein problems that he has unconcernedly foisted upon a generation utterly unable to cope with them, and about the obligation that rests upon him to stop inventing machines and turn his almost legendary energy and skill to inventing institutions that will constitute a solution of the problems he has raised, and contrariwise about his utter inability to offer wise or useful counsel in fields outside the narrow boundaries of his technical training.

Jan 1, 1938

By Tap Pryor

A very small nation with large seabed resources requires a strategy. The simplest approach is to duplicate every step taken by the United Nations (UN), in its own leasing programme. In addition, the smaller nations must sell itself and its competitive offering. It is one thing just to await applicants and/ or tenders, another to work to make the leasing seem like a very good idea. This cap be achieved through publications, correspondence, meetings (such as the Underwater Mining Institute, but especially through pro-active planning, seeking the ideal technologies in both harvesting and processing. The ideal would be some combination that could begin quickly and on a small scale. It must be within the UN environmental guidelines. To meet the "quick and small criteria," simple harvesting and physical processing methods must be given the highest priority. Once these are satisfied, then marketing studies can be completed. There is, of course, a market for every element but only careful engineering and cost analysis will determine accessibility. What is required is a stepwise approach, gaining greater and greater credibility at each step. In fact, much planning can be done for very low cost. In the Cook Islands, the first crucial step was the East-West Center publication which pulled together all facts in one volume and which found the local resource to be richer in significant ways than Clarion-Clipperton. Most seem to believe that it could be many years before full production is possible, but this has been conventional wisdom for so long that it has taken on the suspicious aura of myth. Is it real? Have all possible recent technologies such as robotics and physical processing been taken into account? Either way, it is essential that a comprehensive approach be taken so that all factors from resource to market are considered as inter-related until a single business plan emerges. When that is in hand and when its profitability and risk levels are found to be credible, adequate investment funds are available.

Jan 1, 1994

By A Watson

We tend to overestimate the volume of water used to process ore and the evaporation from tailings and heap leach stockpiles. During mine operation, a significant portion of the water collected from onsite water management systems is consumed and recycled by ore processing and lesser portion discharged to the environment. When mining and processing cease, however, the mine site water balance is altered and the real effort and cost associated with managing and disposing of excess mine-influenced water becomes evident. As these flows can no longer be recycled and may not be suitable for discharge to the environment, the cost of dealing with them can comprise a significant portion of the post-mining liability. The problem of dealing with large volumes of mine affected water has the potential to become worse in the future due to the established trend of lower grades which require more water per unit of mineral processing. As a result, future mines may be expected to have greater water needs and problems than we experience today.This paper discusses various aspects about how water usage changes when a mine transitions from operation to closure based on observations and numerical simulations of made with site-wide water balance models. The intention is to provide general considerations for mine operations in planning for end of mine life and post-mining care and maintenance.

Jan 1, 2009

By L. Alan Weakly

The Powder River Basin is the largest strippable reserve of compliant coal in the United States. It is the mother lode, for this Basin is currently supplying 25 percent of the coal produced in the US annually. This paper updates what has happened in the Basin since 1993 in terms of increased production, higher productivity, changes in mine ownership, safety statistics, new equipment, latest coal technologies, and electrical deregulation ramifications.

Jan 1, 1998

By J. A. Reid

THE views and observations expressed herein on this old but constantly recurring question are our own, no effort having been made to align them with standard texts. Therefore, while they may find general acceptance amongst fellow engineers, they must stand as personal opinions and as such are open to debate and discussion. In order properly to consider the subject, it should first be 'set in proper perspective. Why are Prospects Examined? Prospects are examined to determine whether they may contain economic concentrations of metals or minerals, the legitimate mining business being run, pretty largely, to make money. Next to food and clothing, modern civilization is based on metals, with which are included in this discussion minerals, oils, and fuels. A constant and increasing demand for the common metals requires the location of replacements for depleted orebodies, while the use and appreciation of new metals brings increasing demand for them. Aluminium is a good example of a metal which has, within recent years, made great progress. Today, we are becoming increasingly aware of magnesium, chromium, tungsten, thallium, and other lesser known, metals.

Jan 1, 1945

The profitability of individual ore blocks can be classed as clearly profitable, clearly not profitable, and those in between which are by nature quite sensitive to their major cost and revenue drivers. It is often the case that the most effort goes into the least profitable ore blocks to ensure that these will in fact not generate a loss. In these cases a cut-off grade policy is often not sufficiently live to separate individual sources given the volatility of financial markets and individual circumstances of some sources particularly in remnant operations such as Mount Isa MinesÆ Lead Mine. Standard sensitivity analysis can determine which factors stope profitability is most sensitive to. However, this does not usually indicate the likelihood of any input change, nor the combined effect of multiple inputs changing. The author attempted to modify the Lead Stream financial model that determines cash margin by inserting probability distribution functions and then using Monte Carlo simulations to determine the probability of any particular ore block making a profit. This effectively demonstrates the combined effect of varying a number of inputs simultaneously to provide a probability of making a profit. The limitations of this analysis lie in the accuracy that individual probability distributions can be specified. Attempts to generate valid functions from first principles have proved difficult for a number of reasons and these are discussed along with some practical alternatives.

Jan 1, 2002

By Frederick Bird

This paper is based upon a review of studies of mostly Canadian mining companies in Chile, northern Canada, Tanzania, Guatemala, Ghana, Sierra Leone, and the Democratic Republic of Congo. In spite of often well-meaning efforts most mining firms produce wealth in developing areas that largely benefit those immediately involved, sometimes neighboring communities, and often those in the governing strata. Typically mining takes place in enclaves and fosters enclave development, rather than the kind of inclusive wealth development favored by the recently UN published Inclusive Wealth Report. One way by which mining operations can foster more inclusive wealth development is to adopt much broader approaches towards the construction of the various physical and social infrastructures ? roads, water, electricity, health services, schools, security ? required for their own operations by collaborating with diverse regional, provincial, and/or national agencies and businesses to develop these infrastructures for larger populations and areas beyond the immediate sites where they are operating. Established mining firms can also foster more inclusive wealth development by establishing more formal, collaborative relationships with artisanal miners.

Aug 1, 2013

By Arthur Mackwell

The role of the precious metals is changing rapidly. They are becoming primarily materials of modern industry, and their decorative and monetary functions are diminishing in relative importance. Certainly gold is still the premier metal for jewelry, as silver is for silverware. But these uses are not growing nearly so fast as are the uses of these metals in a variety of industries. This is even more true of the platinum metals. Moreover, this is true despite the fact that the precious metals are highly expensive and liable to substitution by the base metals in cases where this is feasible. For the fact is that the physical and chemical properties of the precious metals make them relatively invulnerable to substitution; where they can be replaced by the base metals, they have been, and the opportunity for further substitution is, therefore, limited. SILVER In November 1969 the United States Treasury stopped minting the only remaining coin with any silver content. That was the silver-clad Kennedy half dollar, which had a silver content of approximately 40%. The step was taken out of necessity, because of the rising shortfall between world mine production and consumption. It was important to divert the 35 to 40 million oz of silver per year used for the minting of this coin into the open market, where it would be available for industrial consumption. This decision was important, not only for its practical effect but also for what it symbolized. Only four years earlier, in 1965, the Treasury had used 320 million oz of silver" for the full range of coinage. Now not an ounce of silver goes into the United States coinage. The reason is simple and yet complicated. For many years the U.S. Treasury had purchased silver at prices which provided a subsidy to domestic producers. As a result, silver producers were eager to sell to the Treasury, and that agency built up a huge supply of the metal -almost 2 billion oz by- 1961. But, as the free-market price neared $1.29, the basic melt value of the coinage, the Treasury became a seller of silver, not a buyer, and its stock was depleted rapidly. The Treasury lost more :than a billion ounces of silver in the years 1962 through 1965, and it continued to lose silver, both through coinage and through sales to consumers, through 1969. The Government continued to sell silver to consumers at the rate of 1.5 million oz a week, even after terminating the 40% silver Kennedy half dollar. But it was apparent that the Government stocks could last no more

Jan 1, 1976

By J. B. Morrow

Methods of Coal Preparation Fundamentally, the object of coal preparation is to increase, economically, the value of a fuel by making it more suitable to the uses of the consumer. This can be accomplished in three major ways: 1.Screening or sizing 2.-Mixrng or blending 3.-Cleaning By combinations of any or all of these methods we can prepare coal to meet standard specifications-a process of standardization which is the more desirable the more nearly it approaches the unvarying quality of packaged goods, where the package you buy today and tomorrow is the same as that you bought yesterday. It should be noted that it is readily possible to get good cleaning and still have poor preparation because of faulty screening and mixing, and, on the other hand, it is possible to get a passable grade of cleaning, combined with good screening and mixing facilities.

Jan 1, 1931

By L Zhang

The Chinese coal industry is the largest coal producer in the world. The total production in I995 was 1.28 bnt. On the way towards introducing a market economic system, this mature industry is facing major challenges. The main problems are a large surplus of manpower, shortage of current assets and capital, low productivity, high casualties and a huge deficit. This paper discusses the present situation and the future developments in the Chinese coal industry. The current policy can be stated as ‘rapidly developing the state collieries and improving the village and private mines; integrated development to achieve an economic operating scale and encouraging a diversified economy; rapidly exploiting and developing in the North west and South west; promoting productivity and efficiency; welcoming multi-sources and types of investment; setting up coal exchange markets; and the careful control of resources and the environment'.

Jan 11, 1996

By R. B. Moore

IN 1914 the writer and K. L. Kithil announced, through Bulletin 70 of the U. S. Bureau of Mines, that the United States possessed the largest deposits of radium-bearing ore in the world. At that time a small amount of this ore was being, mined and shipped to Europe, and one company was preparing to start the extraction and recovery of radium in this country. The importance of our carnotite deposits in Colorado and Utah up to the publication of Bulletin 70 was not, however, appreciated by anyone.. At that time the total supply of radium in the world was about 10 g., calculated as element, and when I estimated that at least 100 g. of radium element, and probably 200 g., would be produced from our carnotite deposits, there was a considerable amount of skepticism. Up to the present time almost 200 g. have come from this ore, and some writers put this figure a little higher. Uranium ore was found in the copper mines of the Union Minière du Haut-Katanga at Luiswishi in 1913. Later discoveries were made at other places in the Belgian Congo, and the Katanga ores now represent the largest supply of radium-bearing ore in the world. In fact, since 1923 very little radium has been produced from American carnotite, the Katanga ore representing practically the world's supply of. radium since that date.

Jan 1, 1930

By T. F. Bamber

The South Nottinghamshire Area has not been greatly troubled by spontaneous combustion until the last few years, during which the Blackshale Seam has been developed and exploited. The problem was first encountered at a colliery which was heavily preoccupied with a major reconstruction scheme, and with the sudden appearance of a completely new hazard both men and management had to adapt themselves very quickly to meet the situation. The paper contributed to the Symposium by the South Nottinghamshire Area illustrates the problems by reference to actual incidents, and shows how the lessons learned from them have been applied to the shaping of future policy on the avoidance and treatment of spontaneous combustion.

May 23, 1905

By E. Ozberk

The copper and nickel smelting industries are important contributors to the technical and economic well-being of Canada while some of the smelters are among the largest sources of sulphur dioxide emissions in Canada. A review of the operations in six smelters - Falconbridge Limited, Falconbridge, Ontario; Hudson Bay Mining and Smelting Co. Limited, Flin Flon, Manitoba; Inco Limited, Copper Cliff, Ontario and Thompson, Manitoba; Noranda Mines Limited, Horne Division, Noranda, Quebec and Gaspe Mines Division, Murdochville, Quebec - have shown that about 80% of the total sulphur input to these smelters was emitted to the atmosphere in 1980. A simultaneous review of the existing and emerging technologies which can directly or indirectly reduce the sulphur dioxide emissions indicated that it is possible to reduce the emissions to below 20% of the sulphur input to these smelters. This can be achieved by varying degrees of modifications to the smelting operations and installing sulphur fixation facilities at significant costs which may increase the metal production costs. This would consequently make the competitiveness of the Canadian copper and nickel producers more difficult in the already tough world metals market.

Jan 1, 1983

FOLLOWING the presentation of the papers by Messrs. Mahan and Butler, the discussion printed below ensued. A. C. LANE* With particular reference to the New England con-sumer, I entirely agree with Mr. Mahan that intelli-gent marketing methods will do a good deal, but there is more than one way of improving them. For instance, coal can be shipped best to New England about this time of year-after the storms of the winter and before the movement of crops in the summer. For that reason there ought to be seasonal freight rates. This will be agreed to by most coal men if you will ask them, especially those who are connected with large concerns like the Metropolitan Coal Co., and yet they do not get seasonal freight rates partly because the railroads are afraid if they once reduce them they will never have a chance to get them back again. But it would be an improvement to have seasonal freight rates. Another thing: When we are buying in New England we want really a certain amount of heat value in our coal. There is no great advantage in our buying ash, nor is there any particular advantage in the railroad shipping ash and clogging the circulatory system of the body politic any more than clogging the circulatory system of the physical body. It would be desirable if the wholesaler, and to some extent the retailer, could guarantee the amount of ash or sell their coal on heating value. If you are interested in that you will find some interesting charts, in "Anthracite Coal Costs Analyzed," a pamphlet issued by the Anthracite Coal Consumers Association, Inc., New York City, as to rates from various and sundry points for bituminous and anthra-cite coal from the field to New York, Buffalo and Chi-cago. Here in New England they are both up against the competition of oil. About 3 or 3 1/2 bbl. oil will do the work of a ton of coal. One of my millionaire friends who is well posted on the situation is putting oil in his Commonwealth Avenue house because it is the most economical. Moreover, we can get Welsh coal from across the water (and help equalize this matter of exchange with Europe) in close competition with Penn-sylvania coal.

Jan 4, 1928

By G. M. Carr-Harris

"THE SUBJECT of permanent molding has received a great deal of attention in the technical press as illustrated by the many excellent articles in the bibliography which follows. In general, this covers the period 1940-1958 and is merely representative of what is available. Numbers in •brackets refer to items in the bibliography.It may be desirable at the outset to give a few definitions covering those terms directly related to this subject. The following is a definition of permanent-mold casting as given by J. W. Meier in a paper, ""The Non-Ferrous Metals and Alloys"", read before the Ottawa Valley Chapt.er of the American Society for Metals:""Permanent Mold Casting is used where a large number of castings of the same part are required and higher mechanical properties, greater density and closer tolerances are essential. Since metallic mold s are very expensive, the number of castings must be sufficient to, defray, at least partially, the added expense. Molds are usually made from a good quality cast iron, 1but other mold materials, such as the aluminum and copper alloys, graphite, ceramics, etc., are being used in certain cases. Important factors in permanent mold casting are the mold temperature; the proper mold dressing; and, as in all other casting methods, the mold geometry, that is to say, the design of spruces, gates, risers and vents""."

Jan 1, 1960