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By P. B. Leavenworth

Twenty-six fields were found in the Texas Gulf Coast in 1940 as compared to 17 fields in 1939. Of these, 14 were oil fields and 12 were gas and distillate. About 150 wells were drilling at the end of the year. Production for the year 1940 amounted to 104,127,247 bbl. as compared to 100,-253,937 bbl. for 1939. Considerable wildcatting for Wilcox production featured the exploration, but discoveries were few and the type of fields found mainly gas and distillate. On the whole, the program was discouraging. New Fields Alta Lomu. Galveston County.—The Alta Loma field was discovered on May 20, 1940, by the Stanolind Oil and Gas Company's No. I John A. Hulen, which blew out at a depth of 9166 it. and ran wild for several days, with an estimated production of 400 bbl. per hour of 36" gravity oil from a sand in the top of the Frio. Water soon appeared but the well produced more than I3o,ooo bbl. of oil between May 20 and June 10, together with a large amount of salt water. Later the well was killed and recompleted on Nov. 23, for 276 bbl. of 34" gravity oil per day. Probably this was the most sensational discovery of the year, although development to the end of the year was disappointing. The discovery was the result of reflection seismograph work of the Stano-End Oil and Gas Co., the principal leaseholders. Bailey's Prairie, Brazoria County.— Glenn H. McCarthy9s No. I W. B. Munson was completed in a lower Frio sand from perforations 11,345 to II,349 ft. for 8 bbl. of fluid (50 per cent black oil, 27" gravity, and 50 per cent B. S. and W.) on Sept. 24, 1940. It was finally recompleted as a gas well from perforations 11,631 to 11,651 ft., on Oct. 9, 1940. The well had been drilled to a total depth of 11,860 ft. This well produced for only a short time and the area is at present inactive. Blessing, Matagorda County.—The Texas Company's No. I A. B. Pierce was completed from a Frio sand from 8265 to 8300 ft. on July 8, 1940, for an initial production of 29 bbl. of distillate, I 1/2 million cu. ft. of gas. One other gas and distillate well was completed in 1940. Borden, Wharlon County.—J. F. Hutch-ins' No. 2 A. P. Borden Estate was completed on Feb. 11, 1940, for 108 bbl. of 35,6° gravity oil, from a Frio sand at 4758 to 4771 ft. This is the second well drilled in the area by Hutchins. Two other wells in 1940 were failures and there was no activity at the end of the year. Dyersdale, Harris County.-The Dyers-dale field was opened by the completion, on Sept. 15, 1940, of H. C. Cockburn's No. I G. Burkitt from a sand in the top of the Frio, through perforations from 4067-4072 ft., for 240 bbl. of low-gravity oil. By the end of the year the field had been fairly well outlined and did not appear to be a major discovery. Duck Bay, Calhoun County.—Coronado Oil Company's No. I Welder, alter having drilled to 10,002 ft., perforated casing from 5654 1/2 to 5659 it. and was completed for 60 bbl. of 36.8° gravity oil On July 27, 1940, from a Miocene sand.

Jan 1, 1941

By Lloyd A. Morley

A concept is presented to improve underground coal mine electrical system safety and availability. This proposed technique is based upon the ability to predict incipient failures in the mine power system. Prediction is made possible by a new method, developed during this research, which uses a minicomputer to implement pattern recognition algorithms. The theoretical basis of the prediction system is discussed, along with synthesis of the hardware and software sections. The deterioration modes which could be detected are examined, and an evaluation of the system's ability to predict incipient failure is presented. Typical results of the system's performance during laboratory simulation of power system deterioration are given.

Jan 1, 1977

By S. V. Petrov

Oxidised ores possess a significant share among raw materials which are treated by traditional plant technology. As usual, the chemical composition of these ores is rather simple. They can be treated by standard cyanidation. In this case, the resulting wastes have an alkaline reaction. Their toxicity (in case of ROM ores treatment) is mainly due to the presence cyanides and thicyanades. The tails are dexotified before disposal. However, chemical reagents used cannot provide a complete removal of toxic matters. In this case, this disposal poses a real problem because these tails contain a significant amount of CN and SCN and their behavior during a long disposal should be studied. A sample with a simple composition taken from cyanidation tails was studied. The sample presents itself the quartz low-grade sulfide gold-bearing ore. Sulfide sulfur content is 0.15 per cent,and heavy metals content is 0.023 per cent. Method of testing is described further. The samples were tested under moderate and subarctic climates based on the difference in temperature, moisture and the degree of oxygen saturation of air. The pH of water extract, which was prepared using distilled water, was also determined besides measuring the concentration of cyanides and thiocyanates. This demonstrates the stability of sulfide-bearing minerals in the disposed tails. The tests time was 820 days. It was found that the alkalinity of the samples tends to lower under oxygen-containing conditions in proportion to temperature increasing. Under conditions without oxygen, the pH lowering is minimal. Mineralogical and chemical properties of the ore material give positive alkaline balance during testing. The solid sample contains enough alkaline agents to compensate dangerous to the environment reactions of sulfides oxidation.pH value maintaining under alkaline conditions witnesses to the possibility of a safe disposal of this tails type. The largest amount of cyanide is removed under acid-containing conditions at positive temperatures. The higher the temperature is, the more intensive destruction is. At the moment, of finishing the tests at 20ºC temperature, the residual concentration of CN- was 0.06-0.10 mg/L, at 4ºC, the residual concentration of CN- was 0.2-0.3 mg/L and at -18ºC was 0.4-0.6 mg/L. Under conditions with the lack of oxygen, cyanides can be removed within the first 200 days. Then, this process fully stops. A stabilized cyanides concentration is 3.0-4.0 mg/L. The presence of sulfides increases the content of cyanides at the initial stage of testing. Then, the concentration of SCN at the temperatures above 0ºC decreases rapidly under oxygen-containing conditions. At the rise of temperature, a narrowing of peak at the curve and an increase of the destruction process are observed. At the end of testing, the concentration of thiocyanates in the moisture of wastes was 0.2-0.3 mg/L at the temperature of 20ºC and 0.5-0.6 mg/L at the temperature of 4ºC, respectively. The concentration of thiocyanates contained in a frozen sample and media which have the lack of oxygen stabilizes at a certain level owing to sulfides and does not practically change further. It was found that detoxification of oxidized cyanidation tailings with a simple composition which were disposed as filtration cakes can be possible. In this case, the concentration of cyanide in the moisture of disposed wastes can have a close value or equal to actual concentration during cyanidation. In order to meet the requirements of high ecological safety standards and successful detoxification process of toxic compounds in the tails under the action of natural factors, the conditions of air aeration with oxygen for the whole volume of tails are required. Keywords: cyanides, thiocyanates, storage, detoxification, flotation cakes

Sep 1, 2012

The Tasman Orogenic Zone is regarded as a single metallogenic province (the Tasman Province) with four SUb-provinces corresponding with its major tectonic components: the Lachlan, New England, Hodgkinson.and North Queensland orogenic provinces. Within the Tasman Province there are four main ore-rock associations.These are1. manganese and iron with sedimentary and basic volcanic rocks,2. zinc-lead-copper and copper with intermediate-acid volcanic sequences,3. minor chromium, platinum, and osmiridium with ultramafic complexes, and4. tin, wolfram, gold, and copper with syn- and posttectonic granitic intrusions.Whereas the ores of ultramafic and volcanic associations form geographically-restricted metallogenic districts, the ubiquitous granitic ores may be subdivided into twenty-one districts that cover almost the entireOrogenic Zone. The Tasman Province is notably lacking in uranium ores and Mississippi Valley-type deposits.There is a distinct tendency for ores of each association to be progressively younger to the east and north, thus paralleling the progressive growth and stabilization of the Zone. Similar ore-rock associations are present in repeated phases of mineralization from the Cambrian to the Permian-Triassic, reflecting the essential homogeneity of the Tasman Province, and the similarity of the successive tectonic cycles.

Jan 1, 1972

By D A. Deglon

Solids suspension is important in the design and operation of mechanical flotation cells, and is a necessary precondition to particle collection. Most of the fundamental hydrodynamic research that incorporates some aspect of solids suspension was done by Arbiter, Harris, and co-workers, or Schubert and co-workers. However, a need for research into solids suspension in mechanical flotation cells exists, since very little has been done since the late 1980s; a time that also coincides with the advent of round mechanical flotation cells and the subsequent dramatic increases in maximum flotation cell sizes. In this work, concentration profiles and critical impeller speeds, Njs, were measured in a 0.124 m3, round cell fitted with a 0.150 m, Bateman impeller mechanism. Two solids size fractions (75 - 106 and 150 - 250 ¦m) were tested, in ungassed and gassed conditions (JG = 0, 1 cm/s) and at various impeller speeds (300 - 900 rpm). The effectiveness of solids suspension was quantified in three ways in terms of extent of off-bottom solids suspension, suspension height (extent of solids distribution), and variation within the solids distribution, which together present a complete quantitative picture of solids suspension and distribution within the cell. Consistent trends were found when these effectiveness criteria were considered against relative impeller speed, in terms of percentage of critical impeller speed, N/Njs. Off-bottom solids suspension is complete at or above 100 per cent of Njs, with significant sedimentation occurring as the impeller speed drops below 60 per cent of Njs. Suspension heights consistently reached a level equivalent to 90 per cent of the tank diameter at the critical impeller speed, and dropped off significantly as N/Njs dropped below 60 per cent. The variation in the solids concentrations within the sampled profiles showed consistent trends in two-phase but not under three-phase conditions. The paper concludes that the critical impeller speed, Njs, commonly used in the design and operation of standard stirred tanks, is a very useful solids suspension benchmark for describing all aspects of solids suspension in mechanical flotation cells and should be correlated to system conditions.

Jan 1, 2005

By Jeon Jeon, Yong-Kun Choi, Chung-In Lee, Yong-Hun Jong, Hag-Soo Kim

In this study, a computer program to design tunnel blasting pattern has been developed. The program consists of two parts; one is for tunnel blasting pattern design and the other is for blasting modeling to estimate the peak particle velocity, the distribution of fragmentation and the excavation damage zone. We modified the design method of tunnel blasting pattern suggested by Langefors because it provided undesirable pattern in blasting practices such as considerably large center cut and too large burden for Vcut as drilling length increased. As a result, the burden and spacing were reduced to practically appropriate amounts. In addition, the correlation between rock mass rate, RMR, and rock constant in blasting, c, was analyzed based on the data collected from twenty three tests of tunnel blasting. It was concluded that the correlation between them was fairly good enough to be applied in cut design. In order to check the validity of the modified methods and their practical applicability, test blasting was carried out at two different tunnel construction sites in Korea. The results were satisfactory in that the average rate of advance was 90% and the overbreak did not cause additional support. Futhermore, the developed program is capable of estimating peak particle velocity by using (a) the existing vibration equations, (b) the vibration equation obtained by test blasting to check out the practical applicability of the designed blasting pattern. Feedback is implemented into the program to adjust the designed blasting pattern and control the vibration.

Jan 1, 2005

By J. Eriksson

Slag from stainless steelmaking is known to disintegrate, which is an environmental problem and prevents the cooled slag from being utilized. This disintegration is due to the transformation from the ßto the ? polymorph of di-calcium silicate. The transformation is accompanied by an increase in volume of about 11% and a total disintegration of the slag. AOD slag from stainless steelmaking was re-melted in a laboratory induction furnace, together with olivine and calcinated dolomite, to investigate the prevention of disintegration by increased MgO content of the slag with small changes in CaO to SiO2ratio. The modified slag was examined with X-ray diffraction and scanning electron microscopy. The trials showed that an increased MgO content can change the mineral composition towards formation of more Merwinite and Bredigite, which prevents disintegration of the slag. Keywords: slag, disintegration, di-calcium silicate

Jan 1, 2004

By John Guilbert

El presente texto describe la historia del descubrimiento y desarrollo del yacimiento de pórfido de cobre-oro Bajo de la Alumbrera. En ese sentido, dicha minera es menos geológica, teórica y está más orientada a más modelos geológicos, puesto que cuando K. Richard finalizaba la exploración y evaluación del yacimiento de Toquepala en la década del 60, Bajo de la Alumbrera estaba siendo descubierta. Asimismo, la minera se encuentra al noroeste de la República Argentina en una región donde ocurre una cadena de yacimientos de cobre, conocida como el "Cinturón Metalogénico de Pórfidos de Cobre". Allí también existe el complejo volcánico llamado "Farallón Negro" que en superficie contiene muchos sulfatos denominados "alumbres", de donde se originó el nombre de Bajo (depresión topográfica) de la Alumbrera.

Apr 26, 1999

By C. B. Queja

Flexible synthetic membrane liners have become a standard facet to copper and gold heap leach pad design. While gold heap leach operations have utilized most types of synthetic liners, copper leach operations have commonly only been lined with polyethylene. The objective of this study was to determine if there are any chemical reasons why other synthetic membrane types could not be used to line a copper heap leach facility. With engineered consideration, the flexible membrane liner under the ore pile serves two purposes. The first provides a near impermeable boundary which aides greatly in the collection of the metal laden process solution. The second advantage to the flexible membrane is the almost non-permeable barrier to benefit increased environmental awareness that has led to an increase in solution containment technology. The Environmental Protection Agency (EPA) has developed a compatibility test for solutions and membrane liners. The EPA Method 9090 is intended for use in determining the chemical effects of a solution on the physical properties of the flexible membrane liner material intended to contain them. Data from these tests would assist in deciding whether a given liner material is acceptable for the intended application.

Jan 1, 1995

By M. Deniz Turan, HASAN NIZAMOGLU, MÜCEVHER TURAN, RAMAZAN ORHAN

Tailings, or flotation waste, formed during copper production may be considered in the class of valuable wastes because of the amount of copper they contain. With the decreasing grade values of copper ores, the utilization of wastes like tailings that carry certain amounts of copper as secondary sources has become a necessity in both the economic and environmental senses. This study was carried out with the aim of using ammonium derivatives for the recovery of copper from tailings waste produced during copper production and utilizing their complex formation characteristics. In the conditions of six hours of leaching at 30 °C in the presence of 22.5 percent ammonium hydroxide and 100 g/L ammonium persulfate, 91.47 percent of the copper was transferred into the solution, while iron was not transferred, indicating that copper can be selectively recovered from tailings.

By T. S. Montgomery

The performance of carbon-magnesia brick in electric arc furnaces (EAF) is interpreted in light of their observed optical microstructures. Features at the bricks' hot faces were protruding periclase grains, metal globules, graphite-metal contacts and linear void patterns. These features were com-pared to similar features previously seen from microstructures of basic oxygen furnace (BOF) refractories. Modes of formation were sought; an attempt was made to interpret their influence related to wear mechanisms.

Jan 1, 1982

By GEORGE L. CHRISTIAN

T HE Tonopah Extension assay office is a two- story, concrete structure on a solid foundation of andesite, situated about 100 yd. from the company's mill, so that it will not be affected by the stamps or the tube-mills; also it will not be affected by under- ground blasting. On the second floor are the mine superintendent's office and drafting and blueprint rooms. On the ground floor are the assayer's office,' mixing room, furnace room, crusher room, chemical laboratory, parting room, store room, and change and shower room for the mine superintendent, assayers, and engineers. The crusher room is outside of the main building, and has four concrete walls, thus eliminating the jar of the crusher; it is so situated that the least possible amount of dust spreads through the main building. An 8 by 10-in. jaw crusher, which crushes to ¼ in., was made by a local foundry. Attached to the top is a small galvanized-iron hopper covered with a ¼ in. screen, on to which the sample is dumped. The fines-pass through the screen into the hopper, while the oversize is dumped into the crusher. The crushed sample and fines from the screen drop down to a set .of splits suspended from an iron rod below the crusher jaws. The small sample is caught below in a small pulp pan. The rejects drop from the splits through a 2-in. pipe on to a bucket conveyor, which dumps into a galvanized-iron hopper in an upper corner of the room. The rejects drop through a 2-in. pipe to a reject bin outside the build- ing. This bin is constructed high enough for a truck to be loaded from it by means of a chute door on the side.

Jan 1, 1921

By A. W. Gauger

SMELTING of iron ore, manufacture of steel, and the fabrication of ferrous metal products are all processes that require energy. Charcoal was adequate, to supply this energy for the relatively simple processes of the early iron-masters. In the fourth decade of the nineteenth century, anthracite and bituminous coal and later coke supplanted charcoal for the smelting of iron. So far as the chemical phases of the process were concerned, charcoal was an ideal iron-furnace fuel. It had practically no sulphur, and its ash, besides being low in quantity, consisted chiefly of lime and alkalies, thus supplying a part of the flux required for smelting the ore. The ash of coal and coke on the other hand, being largely silica, had itself to be fluxed with bases added to the charge. Physically, however, coke proved to have many advantages over charcoal, which could not be used in the furnaces of today. The chief reason, however, for the change from charcoal to coke was the impossibility of maintaining an adequate wood supply.

Jan 1, 1941

By T. R. Ellis

Many appraisers/valuers believe that the only valuation method available within the Cost Approach category for Real Property appraisal is the depreciated replacement cost method. Some valuation and financial reporting standards setters also believe the same. This paper introduces the minerals appraiser to a number of useful methods for mineral property appraisal that are based primarily on the principle of contribution to value, the predominant economic principle in the cost approach. Most of these cost approach methods discussed are primarily for use in valuation of exploration tracts and resource properties that have no defined reserves. However, the powerful rural cost method can be used to calculate the contribution of categories of resources, reserves, and other property components to the value of a mineral property. This method can be applied to mineral properties at all stages of development, including producing properties.

Jan 1, 2011

President H. M. Howe, Boston, Mass. (communication to the Secretary): Le Chatelier's pyrometer is certainly a most convenient and accurate instrument for the laboratory, and one that may be used under some conditions in the mill. I have used it for several years and with great satisfaction. Like Prof. Roberts-Austen and unlike Herr Blass, I have always found that its indications remain constant over long periods. Like Prof. Roberts-Austen, also, I find it possible, in a quiet place, to read with extreme accuracy ; and, by the use of a telescope, I can read temperatures to within a degree, for some delicate determinations which I have in hand. Variations in the temperature of the room affect the readings of the instrument far less than one would expect. When the current is cut off, the mirror does not always return exactly to the same place; in other words, the zero shifts appreciably, and must be determined often, indeed every few hours if accuracy be desired. In some cases I have had it determined within a very few minutes of every important reading. To this end a switch should he introduced, so that the circuit may be broken readily. With this arrangement we can determine accurately the position of the zero within a very few seconds of the time of taking any especially important reading. The chief causes of the variation of the zero which I have noticed are as follows: a. The suspension may not be tight enough, so that the momentum of the galvanometer frame as it swings makes its supporting wires slip in their bearings. b. Changes in the position of neighboring iron objects may deflect the mirror. c. Changes in the temperature of the room may, perhaps, change the torsion of the suspension wires, and so shift the mirror. d. Dust may attach itself to the galvanometer frame, and by friction against the surrounding fixed parts of the galvanometer, may

Jan 1, 1895

By K. C. Watts

The Silver City mining region is located in Grant County, southwestern New Mexico (Fig. 1). This area is well known, having produced large tonnages of base and lesser amounts of precious metals over the past several years. Mining within the region continues today, as well as exploration activity, which seems to have been on the increase since the recent discovery of a large skarn-associated Zn-Pb-Cu replacement deposit near Pinos Altos, a mineral district within the region (McKnight and Fellows, 1978). Because the Silver City area contains a number of mineral districts and retains promise for additional deposits, as suggested by widespread hydrothermal alteration and favorable igneous rocks, it was selected as the focus of two independent geochemical studies, both seeking to enhance anomaly-to- background contrast in order to improve our abilities to detect blind metal deposits or subtle manifestations of near-surface occurrences. The first of these independent studies involved the systematic sampling of those secondary Fe-Mn oxides that occur within coatings, selvages, and fault fillings, and then the selective extraction of these oxides from the host-rock matrix by chemical methods. The second study sought to isolate clastic Fe-Mn-rich materials from the heavy fraction of stream alluvium. The ultimate source of the clastic Fe-Mn oxides is presumed to be the same coatings, selvages, and fault fillings sought by the direct sampling of joints, but has been transported as a result of lateral erosional processes.

Jan 1, 1981

By Paul E. Scheerer

Synthetically produced magnesium hydroxide serves as the precursor for much of the magnesium oxide produced in the world today. Magnesium oxide, in a variety of physical and chemically reactive forms, is a very important commodity. It is used as the main component in refractories employed in steelmaking furnaces and in many base metal refining furnaces. In the chemical industry, it serves as a raw material in the production of epsom salts, rayon acetate, oxychloride and oxysulfate cements and magnesium sulfonates. It is a minor component in fertilizers and animal feeds. It serves as the starting material for producing fused magnesia, used as an electrical insulator in electric heating elements. It is employed in the magnesium sulfite process for pulp digestion in the paper industry. Additional uses are in SO2 scrubbers, as a neutralizing agent in the tanning industry and as a component in rubber compounding. Magnesium oxide is produced not only from synthetically produced magnesium hydroxide. It is produced from natural magnesites, natural brucites, and natural and synthetic hydro-magnesites. Synthetic magnesium hydroxide, as a starting material provides more control of the chemical purity and chemical reactivity of resulting magnesium oxide products because of the uniform nature, chemical and physical, of the hydroxide that can be produced. Synthetic magnesium hydroxide is produced by precipitation of Mg (OH)2 from magnesium chloride bearing seawater or natural brines through the use of a base such as Ca(OH)2 or NaOH.

Jan 1, 1978

By Stuart Brashear, Robert Brush, Ben Cook

In early 1993, the Piney River quarry owned and operated by the Blue Ridge Stone Corporation of W.W. Boxley, received a series of complaints from the owners of a 130 year-old historic farmhouse that had been converted into a bed and breakfast establishment. Since the distance from the quarry to the farmhouse was substantial, a unique method of seismic data acquisition was utilized to determine if perceived blast effects were caused by air blast or low amplitude, low frequency ground vibration.

Jan 1, 1995

By X. Yang, G. D. Zhai

The prop is the most important part to ensure the proper functioning of hydraulic support. When the hydraulic support is impacted by the roof, the prop is prone to extrusion deformation, expansion, and even bursting. In order to study the stress on a doubly-telescopic hydraulic support prop under impact load, an impact simulation was carried out based on the drop weight method. First, the impact model of the hydraulic system of the prop was established in AMESim software and the dynamic response curves of the bottom and middle cylinder of the prop obtained. Then, according to the conservation of energy, the pressure formulaes in the hydraulic cylinder of the prop under impact load were derived and verified by the AMESim simulation results, and the maximum pressure on the inner surface of the hydraulic cylinder of the prop obtained. Lastly, the transient dynamic simulation of a hydraulic support prop was carried out in ANSYS Workbench software, and cloud diagrams of stress and deformation of the prop obtained using Workbench simulation. The AMESim simulation process describes the change in fluid pressure in the prop, and the pressure formulae can be used to estimate the internal pressure of the prop under impact load. The finite element analysis results show that the stress of the middle hydraulic cylinder is much greater than that on the bottom hydraulic cylinder under impact load, which can provide a reference for prop design.

Jul 2, 2022

By A-M Ahonen

The paper discusses the experiences of a fast-track curriculum designed to provide the industry with engineers capable of working in minerals processing industry. The course has been done once before and the second course has been started. Students chosen have graduated from other fields of engineering. For the first course, twelve students were chosen from 152 applicants and for the second the twelve students were chosen from 96 applicants. The basic idea of the curriculum is to alternate between theoretical studies at the university and working experience periods at industrial sites. In addition, there are several one week assignment tasks at industrial sites. The theoretical periods are six to eight weeks long and there are three of them. During the first period, the teaching concentrates on unit processes and their chemical and physical background. The theme of the second period is mineral engineering systems; flowsheet development, process dynamics, control systems etc. The last theoretical period teaches environmental issues, leadership, project work and other similar topics. Each of the theoretical periods ends with an assignment week at industrial sites. The assignments are designed to wrap up the teachings of the period. For the industrial periods, the students are given learning goals, which have been discussed and designed with their industrial mentors. They are required to find relevant literature, make experimental designs, implement those designs, present the data, and make conclusions of their results. During these periods, a weekly meeting over the Internet is compulsory. Keywords: mineral processing, flowsheet development, process dynamics, control systems, constructivism, zone of maximal development, Vygotsky

Sep 1, 2012