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By Enid C. Plante

To extend our knowledge of the flotation behavior of sulphide minerals, the response of the following minerals to ethyl xanthate as collector was studied by captive bubble and cylinder flotation tests: antimonite (Sb2S3), arsenopyrite (FeAsS), covellite (CuS), rnarcasite (FeS2), orpiment (As&.), pyrrhotite (FeS) and tetrahedrite (4CU2S, Sb2S3). Lollingite (FeAs2) was also exarnined to determine if its behavior could be correlated with that of pyrite or rnarcasite (FeS2. Experimental Method Mineral for Flolation and Contact Tests Mineral was prepared in the manner a1ready described1 and its behavior both freshly ground and "oxidized" was studied. Tests in which the mineral was allowed to oxidize for various periods showed that a uniform response to xanthate was reached in two days or less. Oxidation Products The soluble oxidation products from most of the above minerals were measured and their effect on the flotation of the mineral studied. The mineral samples were wet ground to minus-52 mesh and deslimed, and 20 g of this material placed in 200 ml of distilled water of a measured pH value, and CO2-free air bubbled through each suspension at a constant rate (about I bubble/sec) for 5 days. It has been shown1 that the size of the mineral is unimportant in the rate of formation , oxidation products and that probably the supply of oxygen to the mineral is the rate-determining step. At the end of 5 days the pH value of the 'supernatant liquid was measured again, the mineral filtered off and the soluble products determined. Methods for estimation of sulphur acids, ferrous and ferric iron and copper have already been described.l No satisfactory method was found for antimony. Arsenic was estimated as the arsenate.2 Flotation of "Unoxidized" Minerals with Ethyl Xanthate as Collector Fig I to 3, 4. 6, show the effect of alkali and cyanide as depressants for the minerals with 25 mg potassium ethyl xanthate per liter as collector at 35°C. Wark and Cox8 have shown that with ethyl xanthate as collector, galena, pyrite and chalcopyrite show a greater tolerance to cyanide and hydroxyl ions at room temperature than at 35°C Covellite (Fig I), marcasite (Fig 2) and pyrrhotite (Fig 3) behave similarly. The independence of the curves for pyrrhotite at 35°C with respect to cyanide

Jan 1, 1949

By Giselle de Mattos Araújo

A autorredução é afetada por características das matérias-primas tais como granulometria, porosidade, tipo e teor da fonte carbonácea, e também por características do ciclo de processamento imposto, taxas de aquecimento, tipo de atmosfera gasosa, temperatura média de processo. No presente trabalho objetiva-se, através de testes de termogravimetria, avaliar a cinética de autorredução e também o fluxo térmico associado, durante o processamento de diversas associações de finos de minério e fonte carbonácea. Com os resultados obtidos identificam-se condições que otimizam tanto a mistura autorredutora quanto o processamento, observando-se que em uma mesma faixa granulométrica, o maior conteúdo de Cfixo da fonte carbonácea e materiais mais reativos otimizam a cinética, em detrimento da maior quantidade volumétrica de partículas carbonáceas observada em amostras contendo carvões mais pobres em Cfixo. Taxas adequadamente controladas permitem a definição de instantes distintos para as diversas etapas fenomenológicas envolvidas no processamento da autorredução.

Aug 2, 2018

By Girley Ferreira Rodrigues, Crocce Denise Romano Espinosa, Victor Bridi Telles, Eduardo Junca, Jorge Alberto Soares Tenorio

"Steel sector is responsible for the generation of solid waste, liquid and gaseous effluents. The Solid waste are mainly composed of slag, dust, sludge and scrap. The industry generates approximately 650kg of solid waste per tonne of steel. Approximately 10% of this waste is in the form of dust and mud. The basic oxygen furnace dust is a waste generate by steel sector. Each tonne of produced steel generates 10 to 20 kg dust. Thus, the aim of this paper is study the reduction of pellets made with BOF dust using hydrogen and study kinetic during the reduction. The tests were performed in a netzsch thermobalance to obtain the data of lost mass. This loss mass is coming from iron oxides present in the BOF dust.IntroductionThe generation of solid waste is a problem for many companies in the steel sector. The main solid wastes generated are slag, dust, sludge and scrap [1]. Beyond solid waste liquid and gaseous effluents are also generated.The basic oxygen furnace is responsible for 60% of all steel produced. This sector is the second largest generator of solid waste from an integrated steel mill, contributing with 27% of solid waste generated in a plant ( 5-7 million tons of waste generated annually worldwide) [2,3,4]."

Jan 1, 2013

By Fukui M

An increase in pig iron output by 50 per cent was aimed at after re-lining No.2 blast furnace of NAKAYAMA STEEL WORKS. This had to be achieved by increasing both the furnace volume (from 673 to 757 m3) and its productivity, Without equipment for high top pressure operation, high productivity was mainly attained by the following three measures; (1) improving the gas flow characteristics by maintaining a high ratio of agglomerated ores, increasing the strength of sinter and coke, and optimizing the charge distribution, (2) decreasing the fuel ratio by low Si operation and the use of hot blast, and (3) oxygen enrichment. In addition, the tapping controls for pig iron and slag were intensified. As a result of the above measures an excellent hot metal output of 2.7 tonne/m3/day was attained in April 1979 (monthly average).

Jan 1, 1980

By AIME AIME

ON Thursday, Oct. 9, oil men from far and wide gathered at Beaumont, Texas to participate in a three-day celebration of the fortieth anniversary of the completion of the famous Lucas gusher well at Spindletop field just south of Beaumont, and to pay tribute to Anthony F. Lucas, for whom the Lucas Medal of the A.I.M.E. is named. In the afternoon the gathered host drove to the site of the discovery well to dedicate a 58-ft. granite monu¬ment erected on the spot where the original derrick stood. Representatives of the A.I.M.E. took a prominent part in the dedication ceremonies, giving the two principal addresses of the afternoon's program. Everette DeGolyer, past President, paid a personal tribute to Capt. Lucas, as a pioneer producer, an engineer, and a friend and well wisher of all young engineers. He gave a splendid picture of the useful and full life of Capt. Lucas who always took a great interest in the activities of the Petroleum Division of the Institute, from its inception to the time of his death.

Jan 1, 1941

By C. W. Tomlinson

The analyses which have been made by the writer according to the method described below were made as part of Professor Withey's investigation of the concrete aggregates1 of Wisconsin, in the hope of throwing light on the extent and nature of the influence of the mineral-ogical constitution of aggregates upon the properties of the concrete and mortar made from them. This method was found most satisfactory after four weeks of experiment and modification. It attains an accuracy quite sufficient for the purpose of the analysis, and is fairly rapid. mineralogical analyses may be thus made at a cost considerably less than that of chemical analyses of a similar degree of completeness. The results obtained by this method should not vary in any item by more than 1 per cent. of the total weight of the sample, and may be made very much better than this by the exercise of greater care in the microscopic counting (see below). The accuracy of the hand sorting is of course dependent upon the experience and carefulness of the analyst. After a month's practice, the writer was enabled to turn out these analyses at the rate of four in 33 hr. of working time. It was found most economical to handle four samples at once. The samples analyzed weighed from 290 to 340 g. each. The same method could be applied to larger or to smaller samples, within reasonable limits. The following list covers the necessary apparatus and equipment: 1 good balance capable of weighing accurately to tenths (or, better, hun- dredths) of a gram, and of handling quantities up to 200 g. in weight. 1 Westphal balance, registering densities to two or three decimal places. 1 Meker or Bunsen burner, and gas supply. 1 nest of sieves, 10, 20, 40, and 100 meshes to the inch.

Jan 1, 1916

By W. J. Taylor, T. D. Parris

"Over 90,000 feet of raise have been bored at International Nickel underground mining operations throughout the Sudbury District since the advent of raise boring in the early part of July, 1964. With a total of 10 raise borers on hand at this time, techniques have improved steadily since introduction at INCO mines. The first unit, designed for use in rock of low compressive strength, had to be modified and redesigned to cope with Sudbury Area Precambrian rock. As equipment and boring techniques improved, a specially designed machine for larger holes was developed and is now in use. More powerful units, with a thrust capacity of up to 750,000 pounds, are under investigation. Raises have been bored up to 84-inch diameter, and the changeover to 5- and 6-foot flat reaming heads with improved cutter design has increased performance substantially. As a result, 5-foot-diameter raises have been completed to a length of 750 feet and 6- and 7-foot raises to over 500 feet. Reference is also made to the drilling of over 23,000 feet of drainage and sand-fill holes, ranging up to 7% inches in diameter, with smaller underground rotary drill equipment.Finally, a look into the future indicates the need for further improvements in equipment design to permit economic boring of 7- to 8-foot-diameter raises in Sudbury Area ground types."

Jan 1, 1972

Abrahamson. Guy C., (S'43) Univ. of California, Berkeley. Calif. ' Abrego, Alfredo, (S'43) Texas College of Mines Metallurgy, El Paso, Texas. Adamec, Lew, (S'42) c/o Braden Copper Co., Ran¬cagua, Chile. Adams, Charles E., (S'42) Box 1527, Stockton, Calif. Adams, John W? (S'42) Asst. Petr. Engr., Vander¬ bilt Dist., Magnolia Pets. Co., Edna. Texas. Adams, Karl S., (S'43) Univ. of New Ha mpshire, Durham; N. H. Adamson, Charles R., (S'41) Univ. of Utah, Salt Lake City, Utah. Aguilar, Ruperto G., (S'43) Texas College of Mines, El Paso,. Texas. Almone, Francis M., (S'41) Univ. of Toronto, Toronto, Ont., Canada. Ainge, Ronald Farra, (S'43) Otago University, Dunedin, New Zealand. Akarun, Cevdet A., (S'44) Pennsylvania State College, State College. Pa.

Jan 1, 1944

By E. Chin

The countries of Asia and the Pacific, with their large mineral resource base, are significant suppliers of a wide variety of minerals to both regional and world markets. Australia, China, and India dominate the commercial mineral exploitation in the region. Australia has known reserves of major minerals, which are adequate for both domestic demand, and for exports, and is a significant producer of bauxite; copper; diamond; gold; iron ore; lead; manganese; mineral sands (titaniferrous minerals, monazite, and zircon); nickel; salt; silver; tin; uranium; and zinc. China is the world leader in proven reserves of antimony, barite, ilmenite (titanium), magnesite (magnesium), molybdenum, rare earths, and tungsten. China also has large resources of low-grade iron ore and significant resources of other mineral commodities, such as coal, based on its production and export capabilities. India has significant resources of bauxite, barite, graphite, iron ore, and mineral sands.

Jan 1, 1995

By John E. Udd

In early 2000, CANMET-MMSL was engaged by the Ontario Ministry of Labour (OMOL) to conduct an international study of the practices, in several key mining jurisdictions, of determining the criteria that are used to decide when the wire ropes used in mine hoisting are to be retired from service. Subsequently, the writer visited key officials and institutions in Canada, the USA, the Republic of South Africa, the United Kingdom, Germany and Poland. Material from the Australian province of New South Wales and Hungary was also included. The report that resulted included, among other sections; (1) the history of wire rope and trends in manufacturing technology; (2) a review of mine hoisting practices; (3) the requirements as regards safety factors; (4) a review of the players and the inspection practices; (5) the criteria for rope replacement; (6) a look into the future to outline the developments that could take place in both hoisting and rope inspection practices in Canada; (7) recommendations. Subsequently, the report was issued as a book by OMOL, and as a CD-ROM by the Mining and Mineral Sciences Laboratories, Natural Resources Canada. In this paper the author presents the key findings and the recommendations made in the study.

May 1, 2003

By R. E. Shinkosk

This paper outlines the development of a program for increasing the life of woolen bags used for filtering Dwight-Lloyd gases by treating the bags and gases with hydrated lime. Methods and apparatus are described for determining alkalinity of dusts, acidity and breaking strength of bag cloth. Procedure and results, based on several years of operation, are presented. DURING 1939, additional facilities were constructed in the Dwight-Lloyd Blast Furnace and Baghouse departments at the Selby, California, Plant of the American Smelting and Refining Co. In order to handle adequately the increased volume of gases from the resultant increase in production, it was necessary to increase gradually the amount of water used for cooling gases ahead of the sinter machine baghouse. As a result of this increased water cooling, the average bag life dropped from 27 months in 1939 to 14 months in 1941. (Table I). This drop in life meant an increased. bag cost, as well as lower recovery of dust and some curtailment of operation. During 1941, it was found new bags showed as high as 0.3 pct acidity* after two weeks of opera- tion and as much as 2.0 pct acidity after some months of operation. This high acidity was present in spite of the fact that free oxide or relative alkalinity of the unburned dust ran from 5 to 6 pct. In view of these circumstances, a twofold program was started in Nov. 1941.t Part one of this program consisted of vigorously dipping all new bags in a weak lime solution, containing 50 lb of hydrated lime per 50 gal of water. Part two consisted of feeding fine, dry, hydrated lime into the gas stream intake of the sinter baghouse fan. Apparatus for feeding this lime is shown in fig. 1. All baghouse chambers are shaken in rotation about once each hour. On alternate hours, the baghouse operator places 50 lb of hydrated lime (one sack) into the lime feeder, starts feeder and immediately starts the bag shaking machinery. The rate at which lime is fed is set to coincide with the approximate time necessary to shake all sinter bag-house chambers, or about 15 min. It is felt this method of lime addition is most effective for getting lime into the woolen bag fabric. The amount of lime so fed averages about 600 lb per day. The amount of lime fed per day is varied to keep a minimum relative alkalinity of 9 pct in the unburned sinter dust. A daily dust sample is taken for alkalinity by allowing dust to accumulate in a sample pipe over a 24-hr period. This sample pipe, placed in any chamber cellar, is 2 in. in diam, 4 ft long, is sealed on the inner end, and capped on the outer end. It has a 1/2 in. slot cut for 18 in. along the tip end. This slot faces upward and allows the pipe to fill gradually with dust as bags are shaken. Breaking strength of bags has, in most cases, been the deciding factor in bag replacement. Bags that normally test 100 psi breaking strength when new are replaced when they test under 35 lb. The method for determining breaking strength is shown in the description accompanying fig. 2. Since the start of the liming program in 1941, bag life has increased from 14 months to an average of over 23 months, with a consequent material decrease in bag cost per year. Acidity, as per cent sulphuric acid, may be determined by means of a Beckman pH meter as follows: From a piece of bag cloth. which has been thoroughly cleaned of dust, a 5 g sample is weighed on a balance. Cut the sample into fine pieces and place in a 400 cc beaker. Add 100 cc (measured) of distilled water and stir vigorously. Filter on suction funnel, holding cloth pulp in beaker with a stirring rod. Wash cloth sample and filter wash water four additional times, each time with 20 cc distilled water, the last time squeezing cloth pulp over funnel. Discard pulp and rinse funnel and filter paper. Pour wash solution jnto measuring graduate and make up to exactly 300 cc with distilled water. Place into clean 600 cc beaker and measure the pH on meter. The per cent acid in bag cloth is read from the following table:—

Jan 1, 1951

By David Lowell

"The paper point out the cycles of metal prices, and cycles of exploration that tend to lag one year behind metal prices. It appears that mergers and acquisitions are likely to continue in the currentvolatile industry environment, and a two-tier industry will evolve with giantcompanies representing the upper tier and juniors the lower. Strategic alliances will become more common, but irregular and inefficient exploration financing will continue unless the majors make a specific and consistent effort to solve this problem, and also show more discipline in balancing metal prices and production levels. "

Apr 24, 2001

By M. Akser, M. Tomas

Six Sigma is a methodology that uses a structured and disciplined approach to improve process performance (higher throughput, better recovery, lower cost, shorter cycle time, etc.). Specially trained people called “black belts” lead and manage Six Sigma projects. Black belts, with assistance from their team, ensure that projects follow the DMAIC (define, measure, analyze, implement and control) process phases. Timely completion of each project, with measurable deliverables, is key to Six Sigma’s significant financial success. Implementation of Six Sigma has been growing in recent years in a wide range of industries. The heavy mineral industry, like many other industries, could benefit from what Six Sigma has to offer. Specific Six Sigma project examples are included from DuPont’s Heavy Mineral Production Plant in Florida.

Jan 1, 2005

By Zhaohui Xie, Bin Xu, Qian Li, Yongbin Yang, Tao Jiang

A high carbon low-grade gold ore, in which gold mainly occurs in carbonaceous matters, is a typical refractory gold ore whose conventional cyanide leaching extraction is only 12.9 %. In this paper, by the process of flotation-roasting-leaching, gold was effectively enriched and extracted. The flotation results showed that the enrichment ratio of gold was relevant to that of carbon, indicating that gold occurred in close association with carbon. A concentrate containing gold 7.26 g/t and carbon 12.37 % was obtained, with gold recovery 83.10 % and carbon recovery 90.24 %. Subsequently, the roasting of flotation concentrate favorably made the removal rates of carbon and sulfur reach 99.81% and 98.79%, respectively. After roasting, the gold in the roasted product was further enriched to 29.70 g/t and the optimal gold cyanide leaching extraction reached 93.66%.

Jan 1, 2015

By Brett P. Spigarelli

To meet the growing need for CO2 capture and storage technology, Michigan Technological University is researching CO2 capture and storage using alkali solutions1. Without implementing emission controls, world energy emissions will rise from 29.7 billion t in 2007 to 42.4 billion t in 2035. The first objective of the project was to determine the optimal amount of alkali in solution for CO2 absorption. This was accomplished using theoretical equilibrium calculations and experimental absorption data for alkali solutions of 1, 2, 3, 4 and 5 weight %. As the % alkali in solution increased, so, too, did the ionic strength of the solution. Theoretical calculations took into account the effect increasing ionic strength will have on the solubility of gaseous CO2. The calculations assumed negligible formation of H2CO3, constant temperature and constant pressure. In the experimental setup, a 16% CO2 /balance air gas mixture was bubbled through an Erlenmeyer flask filled with an alkali solution. The gas exiting the flask was fed to a gas analyzer to record the % CO2 in the exhaust gas stream. The % CO2 absorbed was taken as the % CO2 in the exhaust gas minus the % CO2 in the feed. Theoretical calculations found that as the % alkali in solution increases, the solubility of CO2 decreases. This was verified by experimental data, which found that a 2% alkali solution, by weight, was the ideal solution for CO2 absorption. Current research is focused on using the 2% alkali solution for permanent storage of CO2 via mineral carbonation to produce a value-added product.

May 1, 2012

By David E. Siskind

The Bureau of Mines has studied the fracturing produced in the vicinity of large-diameter blastholes in Lithonia granite. Cores were taken from the vicinity of AN-FO production blasts and examined using a total of seven laboratory and field measurement techniques to delineate zones of damage and evaluate the effectiveness of the seven diagnostic tests for fracture-state determination. Laboratory measurements of acoustic pulse velocity, porosity, permeability, compressive strength, and Young's modulus indicated the extent of fracturing with the acoustic techniques providing the best means of distinguishing between fractured and unfractured core. A severely fractured zone was found to extend approximately 25 inches (64 cm) from the center of the 6-l/2-inch blastholes, equivalent to 8 blast-hole radii. A second zone, characterized by a lesser degree of fracturing extended from 25 to 45 inches (64 to 114 cm) or 8-to l4-blasthole radii. Beyond 45 inches (114 cm) the rock was undamaged.

Jan 1, 1974

By William C. Miller

This report describes investigations by the Bureau of Mines designed to establish the noise level and spectrum of various types of pneumatic rock drills and to furnish information that would be useful in conducting sound measurements in mining environments and in reducing the noise generated in pneumatic drilling. These investigations show that (1) the noise generated by the drills in the frequencies below 100 cps is caused by the impact of the piston and drill steel, in the frequency range between 100 and 2,000 cps by the exhausting of air from the ports, and in the frequencies above 2,000 cps by the resonant frequencies of steel drill parts and of drill steel; (2) satisfactory instruments and instrumentation systems are available for field and laboratory measurements; (3) reliable sound measurements can be made in mining environments; and (4) devices can be developed that will abate the noise.

Jan 1, 1963

By C. I. Pierce

The Bureau of Mines conducted laboratory tests to determine if ultrasonic energy could reduce either the residual water or oil content of petroleum reservoir-rock samples from Appalachian area oilfields. Brine-saturated core samples were flooded with oil to residual brine saturation and subjected to 20 kilocycles per second ultrasonic energy. Then they were flooded with brine to residual oil saturation and again subjected to ultrasonic energy. Additional water displaced as a result of the application of ultrasonic energy to the flow system ranged from 0 to 4.3 percent of the original brine and averaged 1.9 percent. The increase in oil recovery as a result of the ultrasonic energy ranged from 0 to 9.0 percent of the original oil and averaged 3.1 percent. On the basis of the tests, it appears that 20-kcps acoustic waves would not have field application for oil recovery.

Jan 1, 1968

By Zhou Lu-Jian

The Port of Shekou is situated at Shenzhen Bay on the east bank of Lingding Ocean. Its coastline is about 6 km long and the water depth near the shore is Favourable. Across the bay is the ' New Territories " of Hong Kong. The port is at a distance of 22-23 seamilesaway from center of Hong Kong and 80 seamiles to Huangpu Harbour of Guangzhou, its highway links with Shen-Guang Highay. Since 19 79 China Merchants Group of the Transportation Department, began to set up Shekou Industrial Zone, the port has been developing and flouri­shing in business. With 15 large or small berths in all, the present portline is 2600 m, and the annual cargo throughout is over 3,000,000 tons and the annual passenger traffic is about 2,000,000 persons. Equalling a medium-scale seaport, it has been officially approved as an oceangoing transit port by the ministry of Transportation. The construction of Shekou port is chara-terized by the self-collected funds and the short construction period. In view of this, the optional plan of the port structure must serve the requirements of simplicity in struture, economy in mate­rial and speed in construction. That accounts for the most application of the sheet piling type to the port in Shekou. Once the project was approved, the cons­truction started. Only within an average period of 7-8 months, a deep water pier was completed and put into operation, which covered series of processes from exploration, designing, tender for con­struction to completion.

Jan 1, 1991

By George M. McArthur

General Statement In Montana, as in most states, the requirements for water quality control are becoming more restrictive. What was once accepted practice is now obsolete. The planning and construction of water quality control facilities has taken on new importance. Past practices and new ideas must be examined to meet the challenge. By this paper we hope to encourage the exchange of ideas for the improvement of water quality control techniques. Both the mining industry and governmental agencies should benefit from such an exchange. The following is a summary of the work done and in progress by The Anaconda Company in Butte to provide an improved water quality related to production processes. We invite your comments. Acknowledgements This paper would not have been possible without the efforts of many individuals and departments in The Anaconda Company, including the Environmental Engineering Department, Mr. Frank J. Laird, Director; Montana Operations, Mr. M. K. Hannifan, General Manager, and their assistants.

Jan 1, 1972