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Introduction Research has shown that when an emergency occurs, work-ers often do not get the information they need to take appropriate action. Important information about incidents is either not com-municated effectively or not at all to those affected by the event. The "Emergency Communication Triangle" safety talk focuses on the content of emergency warning messages. It presents a procedure using mental cues that can be used by senders and receivers of emergency warnings. The talk includes graphics for use during the presentation, as well as references for more information. Background Interviews with 48 miners who had escaped one of three different underground mine fires revealed that warning information provided to them was inadequate. Either insufficient information was provided to miners inby the fire areas or they failed to ask the questions needed to let them plan and execute an effective escape. Most of the miners who evacuated from these three mines did not have information that would allow them to make decisions about efficient escapes. The communication breakdown came from two directions: (1) the individuals providing the warning did not offer details about the situations even though some were known and (2) the individuals who received the warnings did not ask for clarification of the situation. The lack of information allowed miners to continue attempting to place cues into normal frameworks after they should have evaluated the situation as abnormal and threatening. The uncertainty created by the lack of information influenced their decision-making and therefore their actions. Approach Researchers at the NIOSH Pittsburgh Research Laboratory have developed a training intervention that can be used by senders and receivers of warnings during a mine emergency. This material was developed for use in short safety training sessions such as start-of-shift safety talks. The information can be presented in about 15 minutes. Although the illustrations were taken from the underground coal mining industry, the training can be tailored to any work setting by substituting appropriate examples. How It Works During the safety talk, miners learn about the six categories of critical information that should be provided during emergency communications: Who, Where, What, Miners, Event, and Response. • Who: When reporting an emergency or receiving a warning, the first thing a miner must do is identify himself or herself. This is important because people react differently based on who gives them information. • Where: Giving or finding out the location of the problem is important. Of the 48 miners interviewed about their escape, only 2 knew where the fire was located. However, this information was known by either the dispatcher or the person who discovered the fire. • What: Miners must tell or ask exactly what is happening. At one mine fire, miners near the phone heard the message to evacuate and went to gather the others on their crew. One worker shouted to a machine operator: "Come on down to the mantrip. We're going out." Because it was close to quitting time, the machine operator thought they were just leaving the section a little early and went through his normal end-of-shift routine, wasting valuable time. After giving or obtaining the three initial pieces of critical information, miners can then give or obtain details about the response in progress. • Miners: Is anyone hurt? Has everyone been accounted for? When and where was a missing person last seen?

Sep 1, 2004

By Joseph F. Shirley

A froth flotation plant to recover by-product molybdenite must be designed specifically for the selected separation process and the type of ore being treated. However, some general rules concerning by-product molybdenite plant design can be suggested that would be valid for most processes. The term by-product molybdenite in this paper is limited to the recovery of molybdenite from copper porphyry ores, which essentially amounts to selectively separating molybdenite from copper and iron sulfide concentrates. In addition, most of the discussions would apply only to the almost universally used approach of floating the molybdenite and depressing the copper and iron sulfide minerals.

Jan 1, 1979

By Charles Will Wright

THOSE that attended the seventeenth International Geological Congress held in Russia last summer had an excellent opportunity to gather data and to form impressions on the progress made in the industrialization of the country, particularly with regard to the mineral industries. Several trips to places of interest were arranged, supplementary to the technical sessions held in Moscow, the one to the Ural region being that which I selected as being most likely to be of interest. The accomplishments of the last decade in opening up new mines and building new metallurgical plants in the Soviet Union have been outstanding. This could only be accomplished by a central government ready to employ the best technical talent, which was

Jan 1, 1937

By Rajesh S. Ransing

An intelligent tool has been developed to analyse the quality of diecast components. The influence of both design and process parameters has been studied in great detail. The tool, based on expert systems related technologies, can identify the causes for the defective castings manufactured. Design related causes such as gate position; gate area, runner design etc. as well as process related causes such as cycle time, cavity filling time and melt temperature are suggested by analysing the data on defective castings for a manufacturing campaign. This intelligent analysis is useful for both design as well as production engineers in the decision making process. All the causes for the occurrence of defects are classified into two categories. The firs category is the 'rootcauses' i.e. the causes which are related to the actual process, material and design parameters and which can be directly monitored. The second category is more abstract in nature and is classified as `metacauses'. These capture the scientific rationale implicit in the cause and defect relationships. This knowledge on causes and defects is represented in the form of a structured graph rather than by a set of rules, which, coupled with forward reasoning and heuristic search techniques results in an elegant and efficient approach. Uncertainties and the degree of relationship among causes and defects are represented by a fuzzy probabilistic model.

Jan 1, 1994

By X Tian, J Forster, A Olmsted, E R. Bobicki, M Goldbaum, D Boucher, C A. Pickles

As the global demand for metal values expands, it becomes increasingly important to create more sustainable mining operations. Consequently, considerable research and technology development is required to produce processes which are both more energy efficient and have a minimal environmental impact. One potential technology is the utilisation of microwave pre-treatment to reduce the energy requirements in comminution. Microwaves can preferentially heat the valuable mineral phases in an ore and the resulting differential thermal expansion leads to the formation of microfractures along the grain boundaries. As a result of the preferential heating, ore competency is reduced, mineral liberation is enhanced, a coarser grind size can be employed, and plant throughput can be increased. Furthermore, microwave pre-treatment can be combined with advanced ore sorting, to decrease the quantity of gangue material processed downstream and hence reduce tailings production. Previous studies on the microwave treatment of ores over the last 30 years have mainly been limited to low power bench-scale studies and there is a paucity of information on pilot and/or commercial scale studies. In the present research, the microwave heating behaviours of over 40 ores have been studied at the bench-scale. These results were used to generate a database, from which a unique classification system was developed. This system was used to rank the amenability of any given ore for microwave pre-treatment. This knowledge can be employed to predict the performance of the ores in the high-power pilot scale tests and thus can be used as a pre-screening tool. The effects of high-power microwave pre-treatment on grindability and liberation were reported. Additionally, the ore sorting potential was evaluated using a combination of X-ray transmission (XRT) and microwave infrared (MW/IR).

Aug 24, 2022

By Arthur A. Cole

Although the metal silver has been known and prized from very ancient times, it is in the New World that the greatest silver camps have been found. This is shown in the following comparison: [] For the last few years, the World's annual production of silver has averaged about 240 million ounces troy. Of this total, the North American Continent contributes approximately three quarters, Mexico leading with 38 per cent, followed by the United States with 27 per cent, and Canada with nearly 9 per cent.[] Of the largest silver producers in Canada, the Sullivan takes first place. Although primarily famous as a lead and zinc mine, it produced, in 1926, more than 4.5 million ounces of silver. The Premier mine, in northern British Columbia, produced more than 3 million ounces. In Ontario, the largest producers in 1926 were the Nipissing mine, .with 1.9 million ounces, and the Keeley mine, with 1. 7 million ounces. The Mining Corporation produced 1.1 million ounces from mines in the Cobalt district proper, and an equal amount in South Lorrain; while from the Castle-Trethewey mine, in Gowganda, there was an output of slightly less than one million ounces.

Jan 1, 1927

By P. Nelson, B. Salt, J. A. Scott, H. Shang

ABSTRACT In a nickel smelting process, large amounts of off-gas emissions are generated, which can cause serious environmental and plant hygiene problems if not properly treated. With increasingly stringent environmental regulations, an enhanced understanding of well-controlled, off-gas cleaning systems is vital. In this paper, dynamic models for an industrial smelter, off-gas system tackling hazardous sulphur dioxide, carbon monoxide, and carbon dioxide are developed using mass continuity, momentum, and energy conservation laws. The effect of air in-leakage is explored under different operating conditions. The developed models provide an enhanced process understanding and a necessary basis for highperformance control analysis of smelter off-gas systems.

Jan 1, 2011

By Charles H. Rawlins

Reported is work done on processing of steel mill effluents in the areas of dewatering and separation. Much of the waste from these operations is in the form of sludges from scrubbers, in which the primary constituent is iron oxide. Recycling of the sludge&apos;s magnetic fraction has become economically attractive in order to reduce the overall volume placed in landfills. The objective of this research is to determine the effectiveness of combining magnetic and cyclonic forces, to recover iron oxide particles from waste water stream, while decreasing the volume to be disposed. Three different size hydrocyclones, operating within the field of a quadripole magnet, were tested using varying feed pulp densities of magnetite, magnetite/dolomite, blast furnace (BF), and basic oxygen furnace (BOF) slurries. In the first three cases, the percentage of magnetics recovered increased to greater than 95%. The limiting operational factors are; high pulp density for small cyclones, which can cause flow blockage within the magnet field, and extremely fine particle sizes (<2 microns), which cannot be recovered. The results indicate this technique can remove virtually all the magnetic particles from some steel effluents to a 40-50% weight percent solids pulp, on an in line continuous basis.

Jan 1, 1994

By Alan J. Solomon

The function of advertising is communication. Viewing the advertisements of mineral suppliers exposes the reader to a broad spectrum of purposes: announcements of new products, availability and supply, departmental services, company image, etc. It is the advertiser&apos;s hope that the message being conveyed is the same message being perceived by the viewer. To maximize this probability, the advertiser at least must carefully construct precise copy, identify the target audience and select the appropriate advertising medium. A truly successful and efficient ad, however, also must accurately reflect a product&apos;s life cycle, i.e., the rise and fall in demand for a product. Buggy whips and radio tubes are classic examples of items formerly in high demand. Industrial minerals are similarly affected by occurrences of product life cycles.

Jan 1, 1983

By Grant E. Casley

Since 1970 Mount Isa fines Limited has made a significant increase in blister copper production from approximately 100,000 to 155,000 mt per annum and in fact 161,040 mt were produced in the calendar year 1974. Flowsheet developments including fluidised bed roasting and converter slag flotation are discussed, particularly their contributions to minimising major equipment changes in smelting and converting. The use of model- ling and simulation techniques for such an exercise is mentioned. The paper reports the alterations made to both equipment and operating techniques in the reverberatory furnace and converter sections to achieve the regular production of 250 mt of blister per converter day from a 41% Cu matte grade. The effects of flux composition on converting performance are highlighted. The air quality control programme is discussed in relation to its restriction of blister copper production.

Jan 1, 1976

In order to overcome some of the deficiencies associated with conventional fine coal cleaning methods, a novel process known as microbubble column flotation (MICROCEL?) was developed at Virginia Tech. This article provides an overview of recent commercialization efforts and in-plant testing of this technology. The results of the in-plant test work indicate that the MICROCEL technology offers several advantages for the upgrading of difficult to clean coals. The test data have also been used to develop guidelines for the design of coal flotation columns and to validate existing scale-up procedures.

Jan 1, 1991

By M. D. Cooper

IN spite of the uncertainty in the bituminous coal industry during 1933, progress worth recording has been made. Along with other industries, coal has felt the effects of business stagnation, but even in the worst weeks of the past four years, .the total production of bituminous coal in the United States was seldom less than half the production in some of the best weeks of the more prosperous years, a record better than that of many industries. However, the competition of other fuels and sources of power, together with the increased efficiency in the use of coal, has brought anxiety to producers. This has resulted in pressure for reduction of costs, not always by the wisest means. On the other hand, the effort to survive has directed increasing interest toward research, a wholesome development in a difficult situation. Wages, limitation of hours of labor, and the NRA have occupied much time and thought. Following a period .of wage cutting paralleling price cutting, the industry found itself rather suddenly faced by the President&apos;s Agreement, followed in due course by the Code, and then in many places by the agreement with the United Mine Workers. Although there is still some uncertainty in regard to the detailed working out of the new arrangements, there seems to be an honest endeavor by the signatories to the Code and Agreement to work them out in a straightforward manner.

Jan 1, 1934

By Grace N. Broderick

U.S. supply and demand data for coal, by States and regions, were tabulated for the years 1960 and 1965. Estimates are provided of State-by-State quantitative data for the coal industry that can be integrated into State and regional energy balances by source, form, and consumer sectors, and used for estimates of interstate and interregional energy flows. The tables give an estimated total supply of coal available for consumption, and also report the distribution of the supply among the major consuming sectors (household and, commercial, industrial, transportation, and electricity generation). To enable comparison of coal data with those for other energy forms, tonnages were converted to British thermal units (Btu). Future energy analysis studies could be facilitated by changes in the categorization of information collected on the coal industry. The data shown are based primarily on Bureau of Mines source material.

Jan 1, 1969

By J. L. Eakin

The Bureau of Mines determined agents that are effective in foaming heavy brines and oil from gas wells in severe concentrations of sodium chloride, in severe concentrations of calcium chloride, or in moderate oil-brine mixtures. Dynamic foam tests were designed to select the more effective foaming agents. Numerous foaming agents were tested in concentrated simulated brines, in oilfield brines having varied concentrations of ions, in heavy natural brines, and in a commercial brine generally used as a reservoir pressure-balancing fluid. Several agents were detected that could perform efficiently in the field under the most severe saline conditions. Agents that promote foaming in oil-brine mixtures were also determined.

Jan 1, 1965

By P. S. Pashkovsky, S. N. Smolanov

The essence of the method consists in creation of drop of opposite sign at the isolating stoppings, by which air losses through the accident district change direction of their motion. The period of reversal is selected in that way so that air may not find itself in the zone of burning. The method of fighting the fire considered was repeatedly used in the coal mines of the Ukraine. The theoretical basis of efficiency and two examples of use of this method by fighting the underground fires are adduced in the paper.

Jan 1, 2003

By William C. B. Gates

Demolition blasting next to an active railroad can be very challenging because of track safety, blasting vibrations, potential track fouling by blast debris, and short work windows on a live track. Recently, in eastern Washington, one of the major railroad companies has been aggressively constructing a second main track to accommodate the expected increase in rail traffic of natural resource products. To accommodate construction of the second line, the railroad company used blasting demolition techniques to remove an old railroad trestle pier on the Milwaukee Road that was in the footprint of the new track bed. The trestle bridged the present rail line and flanked the track with two massive 550-ton (499 tonne) twin-columned steel reinforced concrete piers. The railroad contracted with a specialized contractor to remove the south pier using blasting demolition techniques. The blasting design presented the following challenges: blasting during live track conditions and short work windows; designing a V-notch blast pattern to ensure the pier fell away from the live track; drilling, loading, and timing of the shot; maintaining blasting vibrations at the track below 4 in./sec (102 mm/sec); maintaining ambient overpressure noise below 133 dB; control of fly rock and debris; and track protection and emergency debris removal plan.

Jan 1, 2016

By H. R. Hanley

IN AS MUCH as the interesting changes in the economics of the zinc industry are covered nowhere else in this issue, and they are related to technological progress in the metallurgy of zinc, some reference to prices and production will first be made. The latter part of 1939 is outstanding in the large war demand for metals including zinc, whereas in the first eight months the demand for zinc was subnormal. The cause of the rapid in- crease in demand was the European war and hence the future is problematical. When the year began zinc was in the doldrums, with low prices, and continued thus until August when an advance in price started, reaching 6.5. per pound early in October. (Prime Western, St. Louis.) Rapid changes in the price of any metal are viewed adversely by the metal industry. The persistent low price for zinc of 4 to 49512 for about two years curtailed production and in one instance closed one large plant for a brief period.

Jan 1, 1940

By Dan Urich

This paper covers the construction and operation of the Grate-Kiln system at the Humboldt Mine. The mine concentrator and pellet plant are located approximately 14 miles West of Ishpeming, Michigan, on the Marquette iron Range. Production of pellets began in mid-July, 1960.

Jan 1, 1962

By Bryan Wilson

Background ?Nickel Rim South Mine started production ramp-up in Q2, 2009. ?The main dewatering pumps were put into use in August 2009. ?3 Feluwa?multisafe?positive displacement pumps ?1700m single lift pumping ?Reliability has been an issue due to the amount of slimes and fibers (from shotcrete) at the pumps. ?Critiqued internal dewatering system to solve some issues we were having with our sumps Findings 1.Much of the final dewatering system was not in place. a)Temporary pain. Difficult to say something is not working when the system was not yet in place as per design. b)Not enough capacity to handle slimes within the system. 2.Need to address issues with the final design: a)Ongoing costs: The end design has operating costs of $2.5 million b)Scoops in Sumps: The end design relies on scoops to be used for cleaning the sumps c)Slimes Recovery: The system mixes 3 different products in the sumps along with the fibers d)Pump repair costs: The existing Tsurumi pumps are too light duty for our slimes

Nov 1, 2011

By A. W. Frolli

This paper, describing the mining and reduction methods and costs at the Oceanic quicksilver mine, is one of a series of similar reports being prepared by the Bureau of Mines on various mines in the United states. The property, which is owned and operated by the Anglo American Mining Corporation, Ltd., is 5 miles east of Cambria, San Luis Obispo County, Calif. It lies in a region of steep hills and sharply incised canyons on the west slope of the Santa Lucia Range at an elevation of about 500 feet above sea level. The climate is ideal for living and operating conditions. A 40-mile paved highway connects the mine with San Luis Obispo, the nearest convenient railroad town.

Jan 1, 1937