Stress and stress management among geoscientists in the U.S. petroleum industry, August 1984: An analysis

For the past three years, employment in the petroleum industry has declined significantly. This, along with many other factors, has created a potentially stressful situation similar to the petroleum industry recession of the late 1950s. A four page Stress Questionnaire mailed to 1000 geoscientists in the U.S. petroleum industry in August, 1984, concludes that geoscientists appear to be coping very well with their potentially stressful situation. These geoscientists rated themselves considerably up-to-date with respect to their professional discipline and show a strong need to grow and develop. They are very personally involved in their work and at least some of the major satisfaction in their lives comes from work, yet they have other important activities outside of work. Among the 504 respondents (50.4% response rate, excluding retirees and blank responses), the majority are not overly depressed, anxious, high levels of self-esteem or resentful; and they have and hope for the future. However, many indicated a need for stress and stress management seminars. The three main stressors among petroleum geoscientists are (1) meeting time schedules, (2) too much work/too little time, and (3) lack of proper resources. Their major methods of coping with stress are (1) physical exercise, (2) talking with a friend, and (3) analyzing and eliminating the cause of stress. If time and opportunity were available, geoscientists would (1) exercise, (2) rest and relax, and (3) apply time management techniques to cope with stress --Abstract, pages ii-iii

Reflected light microscopy, electron microscopy, electron spectroscopy, and x-ray diffraction mineralogical characterization of electric arc furnace (EAF) dusts

The secondary steel industry in the United States generates 600,000 tons of electric arc furnace (EAF) dust each year. Over 5,000,000 tons of EAF dust are generated annually world wide. The dust, which is removed from off-gasses from the high temperature furnaces, is considered by the Environmental Protection Agency to be hazardous waste due to its leachable lead, cadmium, and chromium. In addition to hazardous components, EAF dust contains valuable zinc, averaging 19%. This study was initiated to determine the mineralogy and characterization of the dust to aid in the processing of the dust for metals recovery and rendering the remaining material non-hazardous. Reflected light microscopy, scanning electron microscopy-energy dispersive spectroscopy, electron probe microanalysis, transmission electron microscopy-energy dispersive spectroscopy, X-ray diffraction, Mössbauer spectroscopy, auger electron spectroscopy, electron spectroscopy for chemical analysis, and cathodoluminescence microscopy were applied to the study of EAF carbon steel (CSD) and stainless steel (SSD) dusts to determine the mineralogy and character of the dusts and some processed dusts. EAF dust is composed primarily of spinel solid solution crystals ((Zn,Fe,Mn,Mg,Ca)(Fe,Mn,AI,Cr)2O4) and zincite (ZnO). Most of the spinel crystals are crystallized within a Ca-Fe-Si glass matrix. Some of the \u3c 1 µm spinels are euhedral crystals. Zincite is predominantly in the fines. Large zincite forms rounded aggregates and \u3c1 µm zincite forms elongated crystals. The abundance of zincite increases with increasing zinc content. Coke, sylvite, hematite, metallic iron, and periclase are minor phases in all of the CSD studied. Halite, fluorite, and wustite are minor phases in most of the CSD. Calcite is present in some of the dusts. SSD varied from the CSD in a greater abundance of sylvite and the presence of halite and 304 stainless steel as minor phases in all the SSD. Lead is present in clusters of 200 – 500 Å spheres in association with phosphorus. Lead is present on the surface of particles to a few atomic levels deep in association with oxygen, fluorine, sodium, zinc, and/or chlorine in the CSD. Lead is not present on the surface of SSD, which have sylvite and halite surface coatings. Chromium is present as Cr3+ in solid solution in the spinel crystals. Leachable hexavalent chromium was not identified and is suspected to be present in very small quantities, with most of the chromium (0.23% total chromium) as trivalent chromium in the spinel crystals. Cadmium averages 250 ppm in the CSD studied and its mineralogical form was not identified. Chlorine is present as sylvite, halite, hydrophilite, Cl-bearing lime, and Cl-bearing coke. Fluorine is present as fluorite. Chlorine and fluorine are deleterious constituents to the processing of the dust. Furnace processing recovers zinc through volatization. Residues from an experimental flash furnace were studied to determine the mineralogical form of the unrecovered zinc. One to two percent zinc was retained in the slags in solid solution with wustite. Pyrohydrolysis is another experimental technique being tested for EAF dust treatment. Residues from pyrohydrolysis tests show the silica and tungstite additives reacted with the dust forming willemite and scheelite. This process eliminated zincite, sylvite, halite, and fluorite. Some of the scheelite formed rims surrounding the spinel crystals, which would deter tungsten recovery and reusability. Reflected light microscopy, in conjunction with electron probe microanalysis and X-ray diffraction, have been the primary research techniques employed in this comprehensive study of EAF dusts. The mineralogy and character of EAF dusts are more fully identified and understood by the research presented in this dissertation. This is vital information for future recycling of EAF dust for metals recovery and processing to render the dust non-hazardous --Abstract, pages iii-v

Process Mineralogy of Roasted Pyrite and Arsenopyrite

Process mineralogical techniques can provide useful information on the mineralogy and textures shown by pyrite and arsenopyrite particles that have been roasted to enhance extraction of gold from refractory gold ores. Dark-field reflected-light microscopy has been found to especially reveal the extent of development of porosity and permeability in the roasted particles. X-ray diffraction has been used to identify the fine-grained, calcium-bearing phases in the roast. Cathodoluminescence microscopy holds promise as a rapid technique for studying the calcium-bearing phases

Mineralogical Characteristics of Electric Arc Furnace Dusts

Reflected light microscopy can contribute important information regarding the mineralogy, mineral abundance, internal textures, sizes and shapes of particles in electric arc furnace (EAF) dusts. Scanning electron microscopy-energy dispersive spectroscopy and electron microprobe analysis are useful to determine the chemical compositions of the specific mineral grains in the dust particles. Furthermore, the mineralogical reactions that have taken place during the pyro-metallurgical treatment of EAF dusts and the mineralogy and textural character of those treated dust samples can be directly observed by reflected light microscopy. Such studies are useful in monitoring the efficiency of experimental pyrometallurgical treatment of EAF dusts which are designed to render them nonhazardous

Refractory Copper Ore from Nchanga, Zambia: A Materials Characterization Study

The Nchanga Cu-Co ore deposit of the Zambian Copperbelt, is hosted in Neoproterozoic siliciclastic-carbonate sedimentary rocks, and it consists of two orebodies: the Lower Orebody (shale) and the Upper Orebody (arkose). Refractory Cu ores present in the Upper Orebody comprise 150 Mt with average 0.87% Cu, and are characterized by inadequate recovery of copper by leaching. This materials characterization study, conducted on refractory ore samples from the Upper Orebody using optical microscopy, QEMSCAN®, and microprobe, has shown that copper occurs mainly in biotite, phlogopite, malachite, pseudomalachite and goethite. QEMSCAN® has quantified the abundance of each phase and total Cu deportment in each phase

Applied Mineralogy of Refractory Copper Ores from the Nchanga Mine in the Copperbelt of Northern Zambia

Certain copper ores from the Nchanga Copper Mine in the northern Zambia Copperbelt are refractory with respect to conventional beneficiation techniques. This paper reviews recent study of those ores to determine their mineralogy, textures and nature of copper occurrence. Two suites of refractory ores were selected for study: 1. samples of stockpiled ores from an open pit, and 2. drill core samples from copper ores. Both sample suites are from the upper orebody at Nchanga and contain about 0.3-1.4 per cent copper as determined by atomic absorption, but they represent separate stratigraphic, mineralogical and beneficiation problems. Ore microscopic examination showed that fine-grained copper sulfides are totally lacking from both suites of refractory ores. Petrographic study found malachite in the refractory ores from the open pit, but that malachite probably is post-mine. The opaque mineralogy of the open pit refractory ores is dominated by goethite that occurs mostly as pseudomorphic grains after pyritohedral pyrite crystals that average 200-250 μm across. Haematite occurs as bands within or as outer shells of the goethite grains. Additional goethite occurs locally as finer-grained areas of exotic goethite. The opaque minerals in the drill core refractory ores are dominated by euhedral ilmenite crystals about 50-175 μm long. Anatase is the dominant opaque mineral in some drill core samples where it is largely pseudomorphic after ilmenite crystals. Goethite accompanies malachite in unusual drill core refractory ores that have experienced intense hydrothermal alteration. Thus, ore microscopy and petrography showed that fine-grained chalcopyrite and bornite and pre-mine malachite were not the causes of the refractory nature of the ores studied. Electron microprobe revealed that most of the copper occurred in solid solution within micas. Application of automated SEM techniques has provided a detailed understanding of the distribution of copper in these refractory ores