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By H. C. Miller

The gas-lift method of flowing oil from wells is the outstanding feature of petroleum technology today. Its forerunner, the air-lift, was used successfully first, in the Baku fields of Russia, in 1899, and later in the Gulf Coast fields of Texas and Louisiana and the Kern River field of California. It is still used to a limited extent in certain oil fields. The use of compressed natural gas for lifting oil from wells has supplanted the air-lift method in a measure in those fields where a sufficient quantity of gas accompanies the oil to make the gas-lift possible, or where natural gas is plentiful and inexpensive. We find, therefore, in California, that natural gas is used at practically every well where a gaseous medium is employed to flow the oil. The use of natural gas has many advantages over that of air. It is possible to recover and save the gasoline from the gas that accompanies the oil to the surface. This gasoline would be wasted if air were used as the lifting medium. Also, certain proportions of air and gas form an explosive mixture that cannot be handled safely by compressors. Another advantage that gas has over air is that gas under pressure is more soluble in oil. Gas in solution in oil reduces the viscosity of the oil that is being produced and causes it to flow more readily through the tubing and flow lines. The gas-lift has made it possible to recover many thousands of barrels of oil from deep wells in California that could not have been produced otherwise. It would not have been economical, had it been mechanically possible, to produce such wells as the world's deepest producing oil well (Miley Athen's No. 6, Rosecrans field, California) by any other method of pumping known today. At this well, production is obtained from between 7305 and 7591 ft. and 11 months after completion of the well, production was being maintained on the gas-lift at approximately 2000 bbl. a month. The crookedness of the hole, or its diameter and depth will not prevent the successful application of gas-lift pumping when other conditions are favorable.

Jan 1, 1928

By Yusuke Kimura, Ken-ichi Yamaguchi

"Secondary materials have long been processed at the S-furnace of the Mitsubishi continuous copper smelting and converting process at Naoshima Smelter and Refinery. Intensive recycling in the recent years has formed concerns that impurities in the secondary materials may cause drastic changes in the chemical properties of the CL-slag, which is separated from matte in the smelting stage. Among various impurities included in secondary materials, the authors have studied the influences of sodium oxides in the CL-slag because the behavior of sodium oxide has scarcely been studied with respect to the copper smelting slag. The examinations have been applied experimentally on the distribution between slag and matte of arsenic whose acidic characteristics suggest strong affinity to sodium-oxide of basic characteristics in silicate melts. The results have been discussed by thermodynamic evaluations and the results of pyro-tests at the commercial furnace.IntroductionAt Naoshima Smelter and Refinery, the existing line of the Mitsubishi continuous copper smelting and converting process has been operated since 1991. The Mitsubishi Process consists of three furnaces namely the S-, CL- and C-furnace as shown in Figure 1. In the S-furnace, copper concentrate and powdery secondary materials (scraps, sludges, etc) are charged through the top lances with oxygen enriched air. The other secondary materials of lumpy shapes are charged through the chute installed on the furnace roof. Charged materials are smelted by the reaction heat in accordance with the oxidization of copper concentrate. The mixed melt of matte and slag overflows through the launder into the CL-furnace, where the melt is separated into slag and matte by the difference of their specific gravity. Matte is siphoned out and sent to the C-furnace and converted to blister copper continuously. The CL-slag overflows continuously through the slag outlet to be water-granulated. Granulated slag is sold as a raw material used for the cement production and so on. Various secondary materials have been processed at the S-furnace of Naoshima Smelter and Refinery. Intensive recycling in the recent years has formed concerns that the chemical properties of the CL-slag may change drastically due to impurities originating from secondary materials. Among various impurities included in secondary materials, the authors have studied the influence of sodium oxide in the CL-slag because the impact of sodium oxide has scarcely been studied with respect to the copper smelting slag. The examinations have been applied experimentally on the distribution between slag and matte of arsenic whose acidic characteristics suggest strong affinity to sodium-oxide of basic characteristics in silicate melts."

Jan 1, 2012

By H. H. Kellogg

The thermochemical properties of molten solutions in the binaries Cu-Bi, Cu-Sb and Bi-Sb, as well as the ternary Cu-Bi-Sb, have been correlated and described in mathematical form by use of the associated species concept combined with the three-suffix Margules equations to account for the non-idea 1 behavior of the solution species. Agreement of the correlations with experimental data is excellent (relative deviation of less than 2.5% in the values of the activity coefficients) in most cases. The correlations are applicable over the entire composition range of each system, and in the temperature range 700°-1250°C.

Jan 1, 1985

By B. L. Chulu

In the carbothermic reduction of lead sulfate to produce lead, the inclusion of soda ash (Na,CO,) in the charge provides for the control of sulfur dioxide in the effluent gas. An important mechanism in the process appears to be the carbothermic reduction of the sodium carbonate whereby sodium gas and carbon monoxide are produced. These intermediates then participate in the reduction of the lead sulfate to produce lead metal and stable sulfur species in the molten slag phase. In addition, there is some evidence that the presence of lead metal in the charge may also serve to increase the lead recovery in the process. These aspects were investigated by conducting laboratory-scale smelting tests with small charges (;3g), at 1173°K(9000C). Recovery did not exceed 74w% and the role of incipient lead metal in the charge could not be clearly assessed.

Jan 1, 1993

By S Hapugoda, H Han, L Lu

Charcoal produced from Syzygium Zeylanicum trees was widely used in ancient Sri Lankan iron smelting practices. Charcoal made from Syzygium Zeylanicum tree trunks, branches and leaves were analysed by optical mineralogy and SEM and found to contain unusually high concentrations of calcium oxalate (CaC2O4.H2O – CaOx) crystals in plant cells. Partial and full reduction tests of a high-P Brockman ore were conducted at several temperatures with coke and coke doped with CaOx and CaCO3. It was observed that CaOx promoted reduction and generated comparatively more metallic iron in reduced samples. Furthermore, CaOx encouraged phosphorous partition into slag phases than into the metallic iron, suggesting CaOx can a potential alternative fluxing material to calcium carbonate for treating high-P iron ores in ironmaking processes.

Sep 18, 2023

A study was undertaken to remove the Se from waste solutions using a raw form of the biomass called Iota Chips derived from the seaweed, Eucheuma spinosum. Removal of Se from solutions was investigated as a function of time, pH, conc. of Se in solution (0.1 to 100 ppm) and lota Chips to liquid ratios of 10-2 to 10-5. For solutions containing initial conc. of 0.1 ppm Se, with the addition of Iota Chips at a solid to liquid ratio of 10-3, the Se conc. decreased to 0.03 ppm in about 3 hours. Iota Chips absorption capacity to the Se and its application to the treatment of the metallurgical processing effluents are discussed.

Jan 1, 1992

Stratiform lead-zinc mineralization at the Pegmont prospect occurs as a 4-6 m thick body interbedded within arkose, schist, amphibolite, and pegmatite of the Kuridala Formation in the Eastern Belt of the Lower Proterozoic of northwest Queensland.The overall structure of the body is that of a strongly crumpled east-dipping sheet. In detail it is subjected to complex and irregular deformation.Gossaneous outcrops of the mineralised body are anomalous in Pb-Zn-Ag content and have been traced, discontinuously, over about 36 km2 in a NNE-trending belt.Below the zone of oxidation, which reaches 25-40 m below the surface, the primary sulphides are galena, sphalerite, and pyrite.Drilling on a 2 km2 area near the discovery outcrops indicates fairly uniform grades of lead and zinc.Changes in thickness of the mineralised body are gradual.

Jan 1, 1977

By K. N. Subramanian, H. Kanduth

"It is well known that chalcopyrite can be dissociated into simple sulphides by heating with elemental sulphur at about 475°C:CuFeS2 + S -> CuS + FeS2Experimental work was undertaken to determine whether this ""activation"" could be used to advantage in the selective leaching of copper from chalcopyrite concentrate.A method of treating copper concentrate with molten sulphur was developed and the activated product was leached in dilute sulphuric acid using oxygen, ferric iron or manganese dioxide as the oxidant. The object was to obtain a solution suitable for electrowinning with minimal purification, but it was impossible to obtain rapid extraction of copper without simultaneously dissolving a large proportion of iron. This was attributed to the fact that some of the copper was present as a low iron-copper sulphide (idaite) and that the pyrite formed during the ""activation"" step was more easily oxidized than natural pyrite."

Jan 1, 1973

By Seyed Ahmad Jenabali-Jahromi

In this paper a meshless method called Finite Point Method (FPM) is developed to simulate the solidification process of continuously cast bloom steel in both primary and secondary cooling region. The method is based on the use of a weighted least-square interpolation procedure. A transverse slice of bloom as it moves with casting speed is considered as computational domain. The two dimensional heat transfer equation together with temperature dependent thermophysical properties is solved in the computational domain. The present work is verified in the mold region by the comparison of the surface temperature simulated by FPM and finite volume method (FVM) and also comparison of solidified shell thickness simulated by FPM and measured on a breakout bloom. For secondary cooling region the validation is done by comparison of the surface temperature simulated by FPM, FVM and thermovision measurements.

Jan 1, 2009

By M. Kosugi, M. Kawata, J. V. Satur, K. Mitsuhashi, R. Kawarabuki, W. Kracht, Y. Ebisu

Copper concentration is becoming more difficult because remaining copper ores are more complex and of finer copper mineral grain size, making copper minerals harder to float because of the fine particle size required to liberate the valuable species. The purpose of this work was to study the flotation behavior of fine copper sulfide ores at different conditions of agitation and aeration. The experimental campaign was carried out in a laboratory Denvertype flotation cell of 1 L volume modified to be operated with forced air that allows decoupling air flow rate and agitation speed. Four ore samples from Chile were used, all of them containing copper sulfides such as chalcopyrite, bornite, chalcocite, and tennantite, but with varying grain sizes and compositions. Preliminary flotation tests for establishing the flotation conditions of grinding size and collector dosage were conducted before the kinetic flotation tests that were carried out at different agitation speeds varying from 900 to 1300 rpm for gas flow rate ranging from 1.6 to 7.2 L/min. The flotation products were analyzed by ICP-MS and MLA (Mineral Liberation Analyzer). The results showed that high agitation speeds with corresponding air flow rates resulted in better recovery than moderate agitation speed and air flow rate, and an excess in gas flow rate resulted in bad performances. The flotation rates of the fine copper minerals were improved despite the different improvement rates among the fine size fractions. The impact of these operational variables, however, was different when comparing the results for the four ore samples. While it was found that the order of floatability in the four samples was the same, that is, chalcocite > tennantite > bornite > chalcopyrite, the kinetic constants of the copper minerals in the samples were different, indicating that mineral composition in the sample affects the flotation kinetics.

Jan 1, 2018

By Richard Kunter

INTRODUCTION Additional work has been done on the CIP circuit at Creede, and a brief description of this work is presented in this paper. DREDGE The original dredge for the Bulldog was built by Al Hack, Inc. of Denver. The dredge cutter head is mounted on a boom made of 6-inch diameter pipe which is raised and lowered by a cable-pulley system. Maximum cutting depth is 8 feet. Slurry from the dredge flows through a floating 6-inch diameter pipe supported on 55-gallon drums which runs from the dredge to the shore and then to a trash screen and pumping system. See Figures 1 and 2. The cutter head, suction pump, winches for dredge movement, and all other operations are controlled from a small operations house located toward the rear of the dredge. All of the basic dredge equipment is mounted on a chassis about 8 ft x 16 ft in size. Additional buoyancy was originally provided by sealed 55-gallon drums supported along the sides of the chassis by a small wooden framework. Additional framework and barrels on the front of the chassis on either side of the cutter boom provided additional stability, particularly when digging in hard material. The dredge was quite stable, but two problems were apparent. For one, it could have been sunk by someone from the shore firing a rifle into all of the barrels. In prime deer-hunting and sportsman country

Jan 1, 1983

By E. Ghali, A. D. Bas

There is a lack of electrochemical studies of oxidized gold ores since the majority of previous studies were conducted with sulphidic gold ores. In this study, the influence of agitation and iron oxide minerals, i.e. magnetite, hematite, and maghemite on gold leaching was investigated by means of galvanic and passivation phenomena. Cyclic voltammetry studies of Roasted Gold Ore (RGO) in de-aerated electrolyte have shown one oxidation and one reduction reaction while three oxidation and one reduction peaks were observed with gold electrode. Galvanic coupling results by Zero Resistance Ammeter (ZRA) mode indicated that magnetite showed a negative effect on gold dissolution while maghemite and hematite showed a positive effect, relatively, as a result of higher galvanic corrosion rates. Generally, gold dissolution was found to increase in the initial 15 minutes. Increasing agitation speed from 100 to 400 rpm resulted in higher galvanic corrosion rates for RGO, magnetite, and maghemite electrodes, while 250 rpm was found to be optimum for hematite electrode. Passive products such as silver and iron-oxide were identified by XPS and SEM-EDS analysis, respectively.

Jan 1, 2015

By F. Czerwinski

Mechanically fragmented chips of an AZ91D magnesium alloy were transformed into a semisolid slurry within the Thixomolding® system. Microstructural analysis of a material at various processing stages revealed that the cold deformation of the alloy, experienced during chipping, led to the recrystallization and growth of equiaxed grains which were subsequently converted to the globular structures by melting the grain-boundary network.

Jan 1, 2004

By Jay F. Colinet

Researchers at the Pittsburgh Research Laboratory (PRL) of the National Institute for Occupational Safety and Health (NIOSH) work to reduce respirable dust exposures in mining operations. One focus of this research is silica dust control for surface and underground operations in the metal/nonmetal mining industry. PRL researchers analyze dust sampling results from the Mine Safety and Health Administration (MSHA) to identify high-risk occupations to guide research efforts. Research is then conducted in an effort to improve existing technologies and/or develop new controls for reducing worker exposure to airborne silica dust. During the last few years, PRL researchers have conducted research related to the following goals: improving protection provided by enclosed cabs on mobile surface mining equipment, reducing dust generation from surface drills, reducing dust levels in iron ore operations, and developing a new method to clean dust from workers? soiled clothes. A description of each of these controls and subsequent dust reductions quantified through site surveys will be provided.

May 1, 2007

The emergence of China as a global economic power has not been without its birth pangs and the current coal market is testimony to this. Traditionally the coal market has been controlled by mature economies that functioned along balanced lines of supply and demand. The emergence of China and India as major forces in the international market has shifted this balance of power from mature economies to the developing economies of China and India. Of late Chinese Central Government policy has caused wide swings in the supply of Chinese coking coal and thermal coal to the international Asian markets. This has resulted in huge increases in demand for coal from producers in Australia, Canada, Indonesia, USA and Russia. Additionally since the late 1990s the liberalised Chinese economy has been growing by between nine to 12 per cent per annum. The corresponding rise in the standard of living of their 1.4 billion people has resulted in a strong demand for raw materials, initially met by domestic production and more recently met by the importation of raw materials including iron ore, oil, coking coal and thermal coal. Commensurate with this growth in China has been the emergence of India (pop one billion) as another major developing economy in the region. Whilst the Indian standard of living is lower than that of the Chinese, this subcontinent still has some 300 million people with middle class consumption demands. India is a major importer of oil, coking coal and thermal coal. It exports iron ore to China with growth parallel to China (seven to nine per cent per annum). These combined new demands from India and China have put unprecedented pressure on the global supply of coking and thermal coals. These pressures are reflected in the current world spot prices for coking and thermal coals which are at historically high levels. Whilst current demand from China and India is high it is anticipated that new projects will partially satisfy this increasing demand. Expectations are that overall thermal and coking coal prices will rise steadily. This paper seeks to identify the potential effects of Chinese and Indian economic growth on the international markets for coal.

Jan 1, 2004

By P. L. Loyselle, B. D. Comilsen, D. H. Carlson, J. H. Johnson

"In-mine airborne particulate samples have been successfully collected and the relative amounts of diesel and coal determined using the Laser Raman Quantitative Analysis (LRQA) method. This method allows analysis of filters which have been collected by a method similar to that used to determine the airborne respirable dust concentration in us underground coal mines. Samples were taken near the feeder-breaker, on haulage vehicles, and in the returns. Sampling methodologies were developed for coal-only and diesel-only particulate reference samples with sufficient filter loading for the LRQA method. A statistical analysis of reproducibility has been carried out. Samples have been collected simultaneously at two locations using the LRQA and the size-selective sampling methods. Good agreement between the two methods has been found.INTRODUCTIONThe goal of this research has been to develop the Laser Raman Quantitative Analysis (LRQA) method to measure the composition of respirable particulate, i.e. the fractions of coal and of diesel particulate, in the mine ambient air. In earlier Bureau of Mines sponsored research, we successfully demonstrated that the LRQA method could be used to measure the fraction of Diesel Particulate Matter (DPM) in coal/diesel particulate mixtures which were prepared in the laboratory.(I) 'The immediate objective was to test and refine this LRQA method on samples collected in a diesel underground coal mine.Specific objectives required to meet this goal include:I) Develop in-mine sample collection methods which will insure sufficient particulate loading on filters for LRQA. ,2) Develop methodology for in-mine collection of reference samples (""coal-only"" and ""diesel-only"" filters) which arc required for quantitative LRQA. 3) Analyze precision and accuracy of the LRQA method. 4) Compare composition measurements with another analytical method, i.e. the University of Minnesota/Bureau of Mines size selective sampling Micro-Orifice Uniform Deposit Impactor (MOUDI) method.An advantage of the LRQA method is that it allows analysis of filters which have been collected by a method similar to that used to determine the respirable dust concentration in US underground coal mines. No new sampling instruments and techniques are required. Transfer of sample from collection substrate to analysis substrate is not necessary. Furthermore, other analyses can be made on the same sample since the technique is nondestructive."

Jan 1, 1988

By J. Drelich, M. Pawlik

An improved experimental procedure to measure contact angle has been consolidated with coal surface preparation involving polishing with abrasive paper, alumina powder, and a cloth, followed by ultrasonic and mechanical cleaning. Specifically, the captive-bubble measuring technique has been compared with the sessile-drop technique and the former has been recommended for the examination of the hydrophobic properties of coal surfaces. Results of the research program, which is currently under way, on the examination of the effect of the nature, amount, size, and distribution of mineral inclusions in coal, on its wettability are briefly reviewed.

Jan 1, 1999

By B. Salopek, D. Rajkovic, D. Rumenjak

In decision making support system, that are used in various fields of environmental protection (environmental impact assessment, environmental management systems, setting environmental standards and regulation, etc.), it is often important to apply various mathematical environmental engineering models. The question of linking environmetal engineering modeling to decision making support system used in environmental protection is not yet methodically solved. The reasons for that could be manifold. Decison making support systems, used in environmental protection, because they are simply taken from bussines decision making, are not often adequate for specific problems raised in environmental protection. On the other hand, there are great number of types of models in environmental engineering, what urges the problem of finding the way of their proper linking with decision making support systems. The application of fuzzy logic in that field is estimated as one of possible solution of the problem.

Jan 1, 2005

By Winton Gale

"The aim of this paper is to summarise the results and conclusions of Australian Coal Association Research Project (ACARP) Report Cl3013 which relate to water inflows into a mine which occur through the overburden above and adjacent to longwall panels. The study assessed available data of inflows into underground coal mines and utilised computer simulation of water flow through fracture networks. The study concluded that flow into mines is typically via an interconnected network of pre-existing and mining induced fractures. The height above the coal seam that mining induced fractures extend is typically related to the width of the panel. However the potential for those fractures to form a connected network which can facilitate flow, is related to the amount of subsidence and the depth of mining. The study compares model simulations with measured data and provides guidelines to estimate the average hydraulic conductivity of the overburden above extracted longwall panels in Australia.INTRODUCTIONWater inflow into coal mines has been a design issue for many years. Guidelines as to the potential for water inflow have been developed in many countries based on local experience and the form of mining being undertaken. In most instances, the guidelines relate to inflows which would endanger underground personnel and operations.In more recent times, water inflow criteria for mines has been widened to include lesser inflows which may not impact on mine safety or operations, but have the potential to reduce water flow within streams and surface aquifers. For the purpose of this paper the larger inflows which are readily measured in a mine or may impact on mining safety are defined as mine inflow and the lesser inflow relating to aquifer water loss as environmental inflow.The water losses referred to are those which enter the mine from the surface or from near surface aquifers.The empirical relationships developed as mine design guidelines or regulations typically relate to high flow (mine inflow) situations and in this paper, these have been reviewed as to their application to environmental inflow. In many cases environmental inflows were unlikely to have been noted or recorded in many mining operations in the past."

Jan 1, 2010

By A. M. Gaudin

Jan 1, 1962