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By J. A. Hillier

The staff of the Hudson Bay Mining and Smelting concentrator have developed a new type of reagent feeder. Several factors encouraged the development of such a system: varying heads caused by the mixing of ores from several mines, the increasing number of flotation circuits operated and reagent feeding stations remote from the flotation operator's work area. The reagent feeders also had to be compatible with future plans for reagent control from an on-stream X-ray analyzer and computer system. The new feeder is a positive-displacement pump set to deliver a constant volume per stroke. At a remote panel, the feed rate is altered by changing the time between strokes. The feeders have been found to be reasonably trouble-free and accurate to less than 2 per cent error.

Jan 1, 1973

By A. V. Tarasov, V. M. Paretsky

"The design is based on the thermal processing of the wastes in· the intensively bubbled melt in the Vanyukov furnace at the relatively high temperatures (1350- 1450 °C), In this case: -the secondary wastes are not formed; - the especially toxic substances at the outlet from the furnace are absent. The technology was tested on a large scale (on semicommersial bases). Technical and economical basis show profitability of recovery complex for processing of hard garbage waste (HGW) using this technology: the period of capital, investments refunding for the, recovery, complex construction with process annual capacity of 240 thousands tons of wastes is 1,5-2,5 years,"

Jan 1, 2000

By Willard P. Ward

Having been engaged during the past year in the manufacture of ferro-manganese in a blast furnace, I have imagined that some further information on this subject might be of interest to that large number of members of the Institute who are engaged in the iron and steel industries. The great question of the economical production of good steel, ingot metal, or homogeneous iron (we scarcely know now what to call it) from good materials, and at reasonable prices, has, thanks to the intelligence and energy of a few American engineers, been successfully solved in this country. Nearly all first-class railroads, and many that would not rank so high, have adopted the Bessemer rail. Martin boiler-plates are rapidly gaining ground, in competition with

By Roger N. Kust

Removal of heavy metals from industrial process streams is becoming increasingly important for _the recovery and reuse of values in process tails. Technology has been available for several years which removes heavy metals, from dilute (0.1-3.0 g/L) streams, as hydroxide or hydrated oxide sludges, allowing discharge of washed cakes with up to 60% solids. This paper reports on improvements to this technology which now allows treatment of streams with metal concentrations in excess of 60 g/L while eliminating the need for thickeners. Streams containing copper, iron, aluminum, chromium, nickel, zinc, cobalt and lead have been successfully treated.

Jan 1, 1992

By Andrew Campbell, Michael Reed

"WorleyParsons has used Discrete Event Simulation methods in conjunction with more traditional process models to assess the performance of copper smelting operations. This work was performed to determine the plant capacities and suitability of proposed debottlenecking options including accounting for the planned and unplanned (breakdowns) shutdowns in the various parts of the plant and supply chain. This paper outlines the methods used along with demonstrating the benefits of selecting a feasible option and minimizing capital and operating costs.IntroductionTraditionally for de bottlenecking studies of smelters and other process plants, a mass balance is performed based on continuous operating rates and expected operating hours. Smelters have several points of failure that will restrict, if not take the entire plant offline. By using a more detailed model, validated against plant experience, bottlenecks can be demonstrated and strategies to remove them to increase plant availability and economic.The modeling simulates the plant performance in real time, and by performing enough simulation the expected long run performance of the plant can be estimated. The models have been built using ExtendSim which is a powerful Discrete Event Simulation software package that is ideally suited to the batch and semi-batch processes and events that occur within smelter operating environments. The value of performing this work is that the operational performance of the plant can be assessed ensuring production targets are met, without using excessive capital outlay."

Jan 1, 2013

Overland conveyor belts that exhibit tracking problems under loaded and unloaded conditions can be tested to' determine the root cause of the mistracking. Moveable conveyors are more prone to mistracking due to structure alignment requirements. In addition, belting quality, splice straightness and carcass condition has a dramatic effect on the performance of a belt in relation to tracking. Methods are discussed that are proven to reduce belt mistracking and improve the operational reliability of the conveyor system.

Jan 1, 1995

By A. R. Conroy

Microscopic observation of physical and chemical changes which take place in various materials under conditions of elevated temperature and controlled atmosphere can often yield valuable insight into the fundamental physical-chemical reactions which control processes in which these materials play an active role. The technique of high-temperature microscopy thus becomes an important tool for basic and applied research in pyrometallurgical and allied fields. Investigators have long been aware of this and through the years have applied the technique to a wide variety of problems. However, up to this time, application has been on a rather limited scale due to the high initial cost of equipment and the relatively low rate of production of data resulting from the complexity of the apparatus and attendant problems in manipulation.

Jan 1, 1964

By D. B. Buddecke

Powell Bend Mine, located in Bastrop County, Texas, is owned by the Lower Colorado River Authority (LCRA). The mine is operated under contract by the Powell Bend Mining Company (PBHC), an affiliate of Pittsburg and Midway Coal Mining Co., and produces 210,000 tons of 6500 BTU/LB lignite per year for LCRA's Fayette Power Project near La Grange, Texas. PBHC operates the surface strip mine one shift per day, five days per week with a total of nine employees; six operations/maintenance and three office/supervision. The mine's productivity in 1988 averaged 100.3 tons per manshift using an l8-cubic yard dragline to uncover the lignite. Delivered cost to LCRA, F.O.B. mine, is $6.11 per ton, which includes water control and final reclamation.

Jan 1, 1990

By A. G. Royle

Sampling formulae for in-situ material, hard rock sampling and alluvial sampling are briefly discussed

May 1, 1991

By Fred N. Kissell

A self-sealing brattice intended for use during coal mine rescue and recovery operations has been designed and tested by the Bureau of Mines. The major design difference between self-sealing and conventional brattice is that the fabric is cut and sewn BS a hemisphere instead of as a flat sheet. This new type of brattice offers reduced weight, leakage, and installation time. Preliminary testing indicates that the concept is worthwhile, but that further developmental research is required.

Jan 1, 1976

By D. M. Conner

An innovative patented process has been developed to convert high volume wastes--fly ash from coal-fired power plants, municipal solid waste (MSW) ash from incineration, solids from waste water treatment and paper mill sludge into a high value and environmentally benign product in the form of a lightweight aggregate. Lightweight Aggregate is widely used in the building construction industry in the United States, Europe and some Asian countries. This paper will present the development of the process, the process itself and details on the first commercial scale plant. The commercial plant is owned and operated by Wisconsin Electric Power (WEPCO).

Jan 1, 1997

By N. H. Coates

The Bureau of Mines designed, constructed, and operated an 18-inch- diameter, fluidized-bed combustor for highly caking coals to evaluate the method for possible application to power generation. In initial tests, combustion was carried on successfully, with carbon losses as low as 0.8 percent. Coal ash was not satisfactory as a bed material, but mullite proved to be acceptable. Overall heat-transfer coefficients from the bed (-20 + 50 mesh mullite) to a water-cooled tube were about 75 Btu/hr-ft2- °F.

Jan 1, 1970

By R. F. Errington

"Radioactive minerals are found together with the more familiar ore minerals in veins, gossans, and pegmatites, Since they have a peculiar property, that of giving off penetrating radiation, the simplest means of field detection is by the use of some radiation detector.The two principal radioactive elements one may encounter are uranium and thorium. These may occur separately or together. At present there is very little demand for thorium and hence radioactive occurrences should be examined with some care to determine which element is present. To do this it may be necessary to have a chemical analysis made of samples from the occurrence. Uranium minerals that do not carry appreciable thorium have a conventional occurrence in quartz or carbonate veins. They are distinctive in appearance. Pitchblende, the principal ore, is hard, black, and very heavy. It weathers readily to soft, powdery minerals •brilliantly coloured orange, yellow, and sometimes green. It may be associated with familiar minerals such _as native silver, nickel-cobalt sulphides and arsenides, chalcopyrite, and hematite.It is the purpose of this paper to review very briefly the types of radiation detectors available .and to draw some general conclusions as to the types most suitable for particular applications.The highly penetrating gamma radiation is the most useful for detection of radioactive mineralization. The alpha rays have little or no penetration, and beta rays are stopped by thicknesses of a millimeter or so of material. We shall confine our remarks principally to those instruments intended to detect gamma radiation. These are of three types."

Jan 1, 1950

By Porter W. Shimer

(New York Meeting, February, 1912.) IT does not seem to be generally known that some American pig-irons contain notable amounts of vanadium, and while the present investigation is far from covering the whole range of irons, it is hoped that, at least, it may serve to call attention to the importance of looking for this element. The majority of the pig-irons investigated were made in the Lehigh Valley and neighboring furnaces, using more or less New Jersey magnetite in their mixtures. Many of these ores, and probably all of them, contain a little vanadium as well as titanium; the ore from one of the largest of these mines contains 0.05 per cent. of vanadium and 0.60 per cent. of titanium. Dr. Thomas M. Drown was the first to detect the presence. of vanadium in the incrustations 1 occurring on certain pig-irons, and he also found this element in a number of magnetites, but the methods for its accurate determination had not, at that time, been well worked out. In a general way, it may be said that the Lehigh Valley pig-irons contain from 0.02 to 0.05 per cent. of vanadium and from 0.10 to 0.20 per cent. of titanium. These elements follow the silicon; that is, the furnace-conditions which produce a high-silicon, low-sulphur iron will cause the maximum reduction of vanadium and titanium, and the lower grades of iron, with low silicon and high sulphur, have a lower content of these elements. The following analyses of irons made from the same mixture, but under varying furnace-conditions, show this very well Vanadium. Silicon. Sulphur. Per Cent. Per Cent. Per Cent. NO. 1 X, . . . 0.042 3.46 0.022 No. 2 plain, . . 0.038 2.26 0.041 Mottled, . . . 0.0'29 0.52 0.106 1 Robertson and Firmstone, Note Concerning Certain Incrustations on Pig Iron,Trans., xii., 641 (1883-84).

Aug 1, 1912

By JOHN R. SUMAN

I WOULD like to spend a few minutes describing to you the present condition which exists in the oil industry and then point out some aspects of this deplorable situation in which I think petroleum engineers can be helpful. As you know, the oil business at this time is in a very critical condition, .due to the tremendous potential production in excess of current demand. This is a world-wide condition as well as a national problem, as it is estimated that the surplus production available for the market in foreign countries is of about the same proportion as that existing in the United States. Due to the inability within the United States to hold production within the bounds of demand prices have been slumping for the last four years and at this time have reached the point where the sales value of the average barrel of crude oil in the United States, is far below the cost, of production. In addition to the large amount of potential production available for the market in excess of demand we have in storage in the United States about six hundred fifty millions of barrels 'of oil. Unless something can be done to limit the amount of oil coming onto the market to a point well below the demand, which point will permit the reduction of stocks, it looks as though the 'oil business is facing demoralization.

Jan 1, 1931

By AIME AIME

THERE is a constant reiteration in some quarters that technical societies are autocratic and that democracy is utterly lacking and that members would welcome democratic societies in which they had full, control of affairs. While we may not speak for other societies, than our own, in so far as th's Institute is concerned such charges- can only come from people uninformed as to the circumstances. It. is no curtailment of the democratic privileges of the members that a -slate is prepared by the Nominating Committee to be voted on at the annual meeting. The Constitution of the, institute stipulates how the nominating committee shall; be chosen and who shall compose it, which prevents anything like- a- clique controlling- the situation. The Constitution further provides how the nominees shall be distributed geographically and the by-laws specify geographical boundaries: for-these nomination districts. Further more, any man or complete ticket can be placed in nomination by means of a petition signed-by only; twenty-five members,- and three or four times such an independent slate has been so nominated and elected.

Jan 1, 1920

By SAMUEL GOMPERS

THE name engineer makes a very strong appeal to one who appreciates the mechanism underlying the fabric of our civilization. Engineers are scouts of civilization. We send them ahead into the lone 'places-the wilderness, the jungles, the great watery expanses, to build the highways necessary for civilized man. The engineers must deal with Nature, with that mysterious dynamic thing we call "force," with materials. It is their function to direct the human activity necessary to coordinate these forces and material in order to make them serve the needs and aspirations of men. Because of my high conception of the engineering profession I was glad to accept the invitation to address The American Society of Mechanical Engineers to voice my understanding of the possibilities of your work as engineers of industry, and to suggest what seems to me the responsibility of the-engineer to the whole modern industrial system.

Jan 1, 1921

By J. McD. Porter

IN many of the old placer-mining districts are still to be found large tracts of gold-bearing gravel not suitable to be worked with a dredge, because the bed is too shallow- or the gulch too narrow. Frequently there is not enough grade to handle the gravel successfully by ground-sluicing or a bedrock flume, or it contains too many boulders to be worked successfully with the ordinary pipe or tube hydraulic elevator. In southwestern Oregon, two practical placer-miners named Ruble, after working for years trying to make money out of placer-ground containing many large boulders, invented and patented a hydraulic elevator of an entirely new type, and one . that has been found to work very successfully in flat' ground and in gravel containing many large boulders. It is a very simple contrivance. A few years ago I acquired the property near Pierce City, Idaho, known as the American placer-mine. Various attempts .bad been made to work this ground. A bed-rock flume had been installed by one company, an Evans elevator by another, and still other methods were tried on a smaller scale. All were unsuccessful. I installed a Ruble elevator, and it has proved very satisfactory. Working under 100-ft. (pipe) head, the 'ground has been handled at a cost of a little less than 8 cents per cubic yard. The conditions at the American mine are exceptionally hard, the boulders being large, heavy, and numerous. Basalt-boulders, up to a size of 16 by 18 by 32 in., have been elevated to a height of 16 or 17 ft., with a 4-in. nozzle-stream, under 100-ft. head. Boulders larger than this size are blasted. At the American mine, a foreman, two pipemen, and two laborers are-required per day of 24 hr. to operate the elevator. Several sizes of this elevator are in use, the one at the American mine being the 25-ft. size, having 25 ft. of grizzly

Oct 1, 1909

By H. J. LONGMORE

MORE improvements have probably been made in the diamond-drill field in the past decade than were accomplished in the entire prior period since diamond drilling was discovered in 1864 by a French engineer named Leschot. True, machines were improved, and new accessories were adopted from time to time up to 1929, but no radical changes were made. The basic principle instituted during the early years of the industry were still in use in 1929. At that time, practically the only diamonds used were "black diamonds" or "carbon." These came from Brazil through a rather round- about route, and by the time they got to the drilling trade their cost was excessive-$175 per carat and even higher at the peak. Perhaps because of this. or perhaps because of increased competition, the industry sought ways to reduce expenses even in the face of constantly increased labor costs due to higher wages and reduction in hours worked. The solution seemed to rest in two things-use of a cheaper cutting medium to replace the carbon diamond and the development of new machines to drill faster and thus produce more hole per shift of operation.

Jan 1, 1940

By E. R. MARBLE

THE introduction of a new fuel, such as natural gas, necessitates careful study where it has not been used previously. At the El Paso smelter natural gas required the installation of apparatus with which no one at the plant was familiar, either as to the type of equipment needed or as to the burning of the gas in it. Observation of existing installations of a similar character and assistance from gas engineers served as a basis to determine what was advisable to use. The gas line entering the plant goes to a metering station equipped with a duplicate system of pressure regulators, a temperature recorder and the gas company and smelter orifice meters in tandem. There are three distribution lines that can be inter-connected at a later date, if necessary, to assist in equalizing the plant load. All the larger lines are of heavy

Jan 1, 1930