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By Larman J. Heath

Wellbore enlargement was tested using hydrazine hydrate in a gas-storage well in Ohio to increase the well productivity. The wellbore was to be enlarged by chemical disaggregation of the sandstone adjacent to the wellbore. Productivity immediately declined 49.1 percent and gradually declined to zero in 7 months. A down-hole camera survey showed a white-to-gray precipitate covering the entire wellbore surface. The precipitate was chemically analyzed and identified as mostly carbazic acid, a hydrazine derivative of carbonic acid. Formation of this precipitate was not anticipated; this viscous sub-stance caused the gradual loss in productivity of the well. The wellbore was not enlarged. Laboratory tests were run to determine what clay stabilization measures could be taken in sandstone cores to prevent clay swelling and particle migration caused by hydrazine hydrate. Normal clay stabilization methods did not prevent the virtually complete loss in permeability to hydrazine hydrate. Other laboratory tests using natural gas diluted with small amounts of carbon dioxide confirmed the ease with which carbazic acid could be formed in a hydrazine hydrate-saturated environment within and adjacent to the wellbore.

Jan 1, 1970

By Allen H. Rogers

THE need for coordinated effort on public problem by engineers has long been felt. Early in June there will assemble in Washington a conference composed of delegates from all the engineering organizations in the country. The call for this conference is issued by the Joint Conference , Committee of the four national societies as the completion of its work on the organization of a congress composed of delegates representing all the engineering organizations of the United States. The plan for this confederation was presented at a joint meeting of the administrative boards of the national founder societies on Jan. 23, 1920; and was unanimously approved in principle by that meeting. The work of the committee since that date has consisted in drafting a constitution of the organization to be presented at the conference for discussion and, after such amendments as may be adopted, acceptance.

Jan 1, 1920

By Manuel Enrique Rodriguez Blanc

A média do tempo tap to tap para refino de uma corrida de ferroníquel era 280 minutos. O objetivo do projeto é alcançar média de 240 minutos. Realizado análise das principais perdas de tempo do processo de refino de ferroníquel, análise dos tempos e métodos do processo de amostragem de ferroníquel e brainstorming com os operadores. A partir destas informações foi realizada revisão na receita de refino de ferroníquel com a utilização de cálcio silício ao invés de alumínio para desoxidar a escória e teste com sensores de silício (sem utilização de CAPEX) e proposto para CAPEX utilização de espectrômetro de emissão atómica/óptica para reduzir tempo de espera por resultados de laboratório. A revisão da receita reduziu o tempo tap to tap de corridas sem sucata para 211 minutos.

Oct 30, 2017

By J. Koskinen, P. Vanninen, T. Leskinen, A. Leppala

Continuous and accurate analysis of slurries has become a critical requirement in mineral processing. With on-stream assay data, automation procedures can be employed to obtain higher recovery and improved control of production. The Courier system was developed by Outokumpu Oy, taking advantage of mineral processing know-how, to provide means for achieving these objectives in the company's ore concentrator operations. It became evident, based on early experience with on-stream analysis, that the Courier should be a complete system to fulfill all functions of the analysis operation. The system includes equipment and techniques for primary sampling, sample preparation for assaying, and processing of data for final assay results. In addition, the on-line X-ray spectrometer unit was developed specifically for industrial use, incorporating a number of technical advances. A new system for converting spectrometric data to assays is based on a physical model programmed on a digital computer. The Courier system is furnished on a turn-key installation basis incorporating all elements needed for operation including calibration. The experience to date with the Courier system at the Pyhäsalmi concentrator is summarized. Reference is also made to recent results with installations at the Outokumpu and Vihanti concentrators.

Jan 1, 1972

By F. M. Benavides

The mining complex being analyzed consists of four mines and two processing plants located in an area where there are several existing modes of transportation. Figure 1 shows a map of the general layout of the four proposed mines and the two existing processing plants. The mines are identified by the numerals "I" through "IV" and the plants by the letters "A" and "B". A proposed overland conveyor would collect the product from all four mines and convey it to Processing Plant A. Alternate transportation systems are as follows: Railroad transport from Mines I and II to Plant B; Highway trucking from Mines I and II to Plant A; Off-the-road truck haulage from Mine III to Plant B and from Mine IV to Plant A. River transportation from the mines to the processing plants was not considered in this study under the assumption that the high capital investments for the loading and unloading facilities, in addition to difficult traffic problems, would make this mode of transportation unattractive.

Jan 1, 1980

By Pinakin Chaubal

The campaign life of a modern blast furnace depends on hearth wear. Distributions of liquid iron flow and refractory temperatures have a significant influence on hearth wear. A 3-D comprehensive CFD model has been developed specifically for simulating the blast furnace hearth. It includes both the hot metal flow and conjugate heat transfer thorough the refractories. The model has been extensively validated using measurement data from actual blast furnaces. Good agreements between measured and calculated refractory temperature profiles haven been achieved. It has been used to analyze the velocity and temperature distributions and wear patterns at different furnaces and conditions. The results can be used to point out the directions for protecting the hearth.

Jan 1, 2006

By G. L. Gates

The waters used to waterflood the Wilmington oilfield were studied by the Bureau of Mines, in cooperation with the city of Long Beach, Calif. Increases in the pressure of the injection wells indicated that they were being plugged by materials suspended in the waters. This study was made to identify the suspended materials, determine their origin, and find methods of preventing their formation. The suspended oil-coated materials were iron sulfide, barium sulfate, calcium carbonate, clay, and sand (or silica). Results indicated that the sulfide, which was as high as 90 milligrams per liter, was the product of sulfate-reducing bacteria. The injection of ocean water increased the sulfate content of the waters in the petroleum reservoirs from 3 to 250 milligrams per liter, thereby furnishing sulfate for growth of the bacteria. The waters were supersaturated with barium sulfate. Laboratory tests showed that sulfide could be removed from the waters by adding iron at a cost of 1 to 2 mills per barrel. The solubility of iron sulfide and calcium orthophosphate in the injection waters was also determined.

Jan 1, 1975

By Robert Glass Cleland

IN SPITE of its widely ramified interests in manufacturing, mines, lumber, railroads, and real estate, Phelps, Dodge & Co. remained primarily interested in exporting and importing, in buying and selling, and William E. Dodge, the directing-partner, consistently styled himself a merchant. After 1849 the profits of the company mounted steadily for seven years until they approached the half-million mark, but in 1857 another severe panic ended the long period of national prosperity that had begun some fifteen years before. Extravagance, indebtedness, and inflation again took their costly toll; or, as the New York Herald of June 27,1857, declared: Governmental spoliations, public defaulters, paper bubbles of all descriptions, a general scramble for western lands and town and city sites, millions of dollars, made or borrowed, expended in fine houses and gaudy furniture; hundreds of thousands in the silly rivalries of fashionable parvenues, in silks, laces, diamonds and every variety of costly frippery are.only a few among the many crying evils of the day. The worst of all these evils is the moral pestilence of luxurious exemption from honest labor, which is infecting all classes of society. The country merchant is becoming a city stock-

Jan 1, 1952

By Bruce Maxwell

The deformation modulus of coal mine pillars theoretically can be reduced by drilling holes in advance of the mining face. This reduction of modulus along the edge of the pillar has the effect of decreasing the stress concentration in the roof; control of roof caving is thereby predicted. Initial field work indicated that a high horizontal stress field existed at the field test site: Subsequent field work was undertaken to confirm the high horizontal stress field and to attempt to relieve the horizontal stress in the immediate roof. A method of softening pillars in conjunction with normal mining activity was developed. Instruments to measure horizontal roof strain, roof parting, roof tilt at the rib, and changes in vertical and horizontal stress in the roof and in the coal were used. These instruments were installed in both softened and unsoftened entries and in locations to indicate the effect of vertical slots in the roof. Significant stress reduction due to pillar softening was indicated, but the effect of this reduction on roof stability was not established. The vertical roof slots relieved the horizontal stress in the immediate roof very effectively, and observations of roof conditions indicated that the slots definitely improved roof stability.

Jan 1, 1977

By C. G. Dunn, J. L. Walter

The c/laracterzstics of cube-oriented nuclei ard other matrix grains that are associated with secondary, recrystallization to the cube texture in high-purity silicon iron were investigated by me-tallographic and X-ray methods. The results show that the structure consists of relatively perfect grains of average diameter between one and two times the sheet thickness ad that the texture has a moderately strong (110) [001] component and a weak (100) [001] component. The results also indicate that matrix stability results from the two-dimensional nuture of the graitzs and that cube-orzented nuclei are neither more Perfect nor larger grains than other matrix grains but have a preferred [001] direction in the rolling direction and have a more effective driving force for growth than other grains because of a low (100) surface energy. THE structures and textures of fine-grained rnatrices determine to a large extent the kinds of secondary recrystallization textures that form on annealing. The understanding of secondary recrystallization processes therefore depends on adequate information about the initial matrices. Matrices usually have three characteristics: 1) they consist of fine-grained primary recrystallization structures, 2) the fine-grained structures are stable toward normal grain growth, and 3) they contain secondary recrystallization nuclei. Stability toward normal grain growth may be due to either a strong single orientation texture (texture inhibition)' or a dispersed second phase (dispersed phase inhibition).2"4 If normal grain growth is not inhibited by either of these two factors, it nevertheless stops when the average grain size is between one and two times the sheet thick- ness.5 This thickness effect satisfies one of the characteristics of a matrix for secondary recrystallization. Its importance in the development of the cube texture in high-purity silicon iron by secondary recrystallization was pointed out by the authors in a recent paper on tertiary recrystallization7 and will be discussed further in the present paper. Assmus, Detert, and he8 have provided some information on a matrix for secondary recrystallization to the cube texture in silicon iron. They found a (110)[001] or Goss texture with enough spread about the rolling direction to include a small amount of the (100)[00l] orientation. The distribution of the [00l] directions was strongest parallel to the rolling direction for both (100) primaries and cube secondaries. These authors found no correlation between size of a matrix grain and orientation and concluded that some property other than size must be the distinguishing characteristic of the cube-oriented nucleus. No consideration was given, it

Jan 1, 1961

By C M. Deosthale, V N. Pangal, M N. Rao

New Mangalore Port is the most important port in Karnataka State, on the west coast of India on Arabian Sea. It handles export of iron ore, granite, coffee, spices etc and imports of crude oil, fertilizers etc. Since 1991, after economic liberalisation by the Government of India, the exports and imports at this port got a boost. Hence the Port Trust felt the need to increase the draught by about 3 to 5 meters for access to bigger ships. In response to a global tender in 1995, the Dutch Dredging Company got the contract to remove 30,000 cu.m of hard granite bed rock, covering 28,000 sq.mtr. area for the Turning Circle and oil Jetty. The operations of drilling, blasting and dredging were to be carried out to deepen the area to about 15 m draught without affecting the normal trade at the Port. This was a time bound contract to avoid interruption by severe Monsoon rains.

Jan 1, 1999

By F A. Rosyid

Mineral resources are national assets which must be capitalised for national development. Those assets should be transferred into real economic capital and then into social capital to achieve national/regional prosperity. Successful development in the mining industry will depend on the correctness in determining the role of mining industries for regional development. Using the context of sustainable development, this paper will analyse the concept and process of mining industry development as an accelerator to achieve regional sustainable development, using the mining operations of PT Newmont Nusa Tenggara (PT NNT) in Batuhijau, Sumbawa Barat Regency as a case study. In the premining activity phase, Sumbawa Barat was dependent on the agricultural sector. Agriculture contributed around 40 per cent of the regional gross domestic product (GDP). Meanwhile, in the activity phase, mining became the sector with the biggest contribution to regional economy. From its operation in Batuhijau, PT NNT contributed around 70 per cent of the regional GDP per year since 2001. In year 2000, the GDP had increased 170 per cent from its figure in 1999. However, due to its depleting reserve, PT NNT will finish its activity in Batuhijau by year 2015. Consequently, the Government of Sumbawa Barat Regency must develop other sectors in the post-mining phase to sustain economic development. Based on location quotient (LQ) and input-output analyses, Sumbawa Barat should develop its priority sectors, ie agriculture, trading and hotel, services and construction to achieve sustainability after mining life. Development of these non-mineral sectors is expected to sustain economic growth in the region.

Jan 1, 2008

By Lóren Kelly de Paula Inácio, Witor Wolf, Renata de Oliveira Melo, Dagoberto Brandão Santos, Graziele Gianini Braga Maria, Nayara Aparecida Lopes Viana

Os aços inoxidáveis duplex combinam as propriedades mecânicas da ferrita com a resistência à corrosão da austenita. Quando submetido a tratamentos térmicos, pode haver precipitação de fases secundárias que prejudicam a resistência mecânica e à corrosão. O objetivo desse trabalho é avaliar a ocorrência de fases secundárias em um aço inoxidável duplex 2205 de grão ultrafino laminado a frio e submetido a temperaturas de recozimento de 600°C a 950°C por diferentes tempos (300-86400 s). Para identificação e quantificação das fases, foram utilizados microscopia eletrônica de varredura, difração de elétrons retroespalhados e difração de raios-x. As propriedades mecânicas foram avaliadas através de ensaios de tração e teste de microdureza Vickers. A presença de fase  e  foi observada junto ao carboneto de cromo, M23C6. A fase  foi confirmada apenas depois do tratamento à 800°C. De modo geral, o aumento do tempo de recozimento leva à uma maior precipitação das fases secundárias. À medida que a precipitação ocorreu, houve aumento da fração volumétrica de austenita e redução da fração de ferrita. Embora a resistência mecânica tenha aumentado, no geral, as propriedades mecânicas, como ductilidade, são prejudicadas pela precipitação.

Oct 5, 2019

By John A. Graves

Anaconda's Jackpile-Paguate mine, located between Albuquerque and Grants, N.M., is situated at an elevation of 6000 ft in a semi-arid desert region. The original Jackpile deposit was discovered by Anaconda air and ground exploration parties in Nov. 1951. A large percentage of the uranium mined in New Mexico comes from the Jackpile-Paguate, which is one of, if not the largest, open pit uranium mines in the world. From 1953 to the present, 120 million tons of overburden, mining waste, and low-grade material have been removed to produce approximately 10 million tons of merchantable uranium ore, having an average grade of about 0.25% uranium oxide. Identifying the Orebody Surface drill holes delineate the ore bodies on a predetermined grid which varies in dimension but usually affords 100-ft control. These holes are probed immediately after drilling by geophysical logging trucks, resulting in a gamma log and digital readout from each hole. From this information it is possible to arrive at an almost immediate conversion to percentage of U3O8 on 6-in. intervals. Initially a hole is probed at a reconnaissance speed of 10 fpm with a time constant of 8 sec. Wherever the gamma recording goes off scale on an initial run, that particular zone is rerun at 2 fpm and at a time constant of 2 sec. This time constant is the interval that emissions are counted and accumulated for recording purposes. The search radius of the Geiger probe is approximately 18 in.

Jan 8, 1974

By John Parianos

"Seafloor mining provides significant potential economic benefits for many Pacific nations that may be “land poor” but “coastline rich,” meaning they have the potential to utilize and profit from the mineral wealth within their Exclusive Economic Zones that extend 200 nautical miles (360 km) out from their coastlines. Within international waters, mineral wealth is the “Common Heritage of Mankind” with additional benefits for sponsoring states and their people.The Solwara 1 Project build continues with significant progress over the last twelve months. The Seafloor Production Tools (SPTs), Subsea Slurry Lift Pump, riser pipe, launch and recovery systems and winches are now complete with delivery to test facilities and the vessel ongoing. Recent focus has been on submerged trials for the SPTs, but the vessel build continues to progress to schedule. Nautilus appreciates the great support thus far from our all our stakeholders.Our focus is to develop the world's first commercial high grade seafloor copper-gold project in an environmentally and socially responsible manner and to launch the deepwater seafloor resource production industry.Nautilus’s marine research continues, including a 3.5-month series of exploration cruises for Seafloor Massive Sulphides in the Bismarck Sea, as well as fabrication of purpose designed exploration equipment."

Jan 1, 2017

We have seen that the first coal development in Pennsylvania was in the Pittsburgh bed in the southwestern corner of the state. The next mining, in point of time, was done in Clearfield County along the West Branch of the Susquehanna River, but the amount of mining done was quite small for a number of years and was soon exceeded by that from the area north of the Susquehanna River in Tioga, Bradford and Lycoming Counties, which will be considered now. It is claimed that coal was first noticed in Tioga County, in 1792, by Robert and Benjamin Patterson who were leading a party of settlers from Williamsport to southern New York, and while clearing a road near the site of Blossburg, found coal, which was said to be good. About 1815 David Clemons made an arrangement with Aaron Bloss, owner of the land, to work some of the coal and hauled the first load down the river to Painted Post, N. Y., as there were no available markets in his own state. Smiths found it an excellent fuel and apparently he found a ready market for the small amount he could transport by wagons and sleighs. As wood began to become scarce around the towns in New York State, the knowledge of the coal deposits in the mountains at the head of the Tioga River attracted attention to the field and the necessity, for means of transportation from it. Some coal had been floated down the river, but navigation was uncertain and dangerous. In 1827 an iron plant was built, and to ship its product and coal, it was proposed to build a canal along the river to reach Corning, N. Y. A company had been chartered in 1826 in Pennsylvania to "make a navigable canal or slack-water navigation" to the state line and coal was shipped on rafts of logs, both being sold, during highwater. In 1828 the company was authorized to build a railroad instead of a canal, and in September 1840, the railroad was completed from Corning to Blossburg.1 That some coal from Pennsylvania had been reaching southern New York towns prior to the improved means of transport is shown by the report of a committee to the New York Assembly: "the bituminous coal has been brought to us either from Great Britain or from that part of our own country which borders on, and lies west and south of the Susquehan-

Jan 1, 1942

By R. P. Smith

The diffusivity of carbon in iron, cobalt, and alloys of 89.7 and 79.3 wt pct Co has been determined by a decarburization method for the temperature range 850° to 1100°C. The Plots of log D us 1/T for the two Fe-Co alloys are linear through the region of the Curie temperature, showing that, unlike some cases of substitutional diffusion, carbon diffusion in these alloys is not affected by electron spin order. RECENT investigations1-' have shown that for substitutional diffusion in iron the change in diffusivity with temperature does not follow an Arrhenius equation, at temperatures near the Curie temperature. Data on the diffusivity of carbon in a iron5"9 indicate that this anomaly does not exist for interstitial diffusion; however, this has not been definitely established. Since cobalt and Fe-Co alloys, 80 to 100 pct Co, have Curie temperatures in a temperature range convenient for carbon-diffusion measurements they are suitable systems for studying the relation of interstitial diffusion and the Curie temperature. EXPERIMENTAL The carbon diffusivity, D, was determined by a decarburization method. The diffusion cylinders, made from small vacuum melts of electrolytic cobalt and plastiron, were about 0.76 cm diam and 6.3 cm long. A small amount of carbon was added to each melt to keep the oxygen content as low as possible. The cylinders were first treated with a hydrogen-3 pct water vapor mixture at 1100°C to constant weight, then carburized to the desired initial carbon content with a suitable CO-C02 gas mix-

Jan 1, 1964

By Rustu S. Kalyoncu

Rainbow colors of roofing granules, adorning the roofs of buildings from single family units to largest office buildings, have their origin in the roofing shingles as burlap soaked with tar appearing as early as the 1700s. Dusting of talc and mica on the coated surfaces, to keep roofing from sticking to itself in storage, represents an early improvement to the original construction product. Sometimes, colored, natural mineral dusts were added as color pigments within the dusting material, for initial color. Prolonged exposure to sun caused the asphalt to become brittle, and it eventually cracked and leaked. Search for solutions to cracking and subsequent leaking problems eventually led to the use of crushed mineral granules on asphalt coated shingles. This provided the impetus for further growth in the asphalt roofing industry. Application of a layer of crushed mineral on the asphalt coating minimized the coating deterioration from exposure to ultraviolet light, thus significantly improving the shingle life. In the 1900s, screened waste from slate quarries was the most commonly used granule in asphalt roofing products. Records indicate the use of coarse slate screenings for asphalt roofing as early as 1906. As the asphalt roofing industry further developed, other naturally colored minerals, such as silica sand, quartz, mica, feldspar, talc, slag, granite, rhyolite, and oyster shells were used on roofing surfaces. Later on, a number of manufactured granular materials, such as crushed brick and tile, fire clay, and white porcelain were used. The first artificially colored roofing granule was produced in 1914 by running molten slag into a solution of alkaline metal silicate, which was absorbed by the porous slag. Various colors were obtained by adding pigments to the silicate coating and by subsequently heat treating the granules. In 1922, another technique was developed in which green slate granules were saturated with copper sulfate solution and heated to 760°C to form copper oxide. Since then, many other granule coloring processes have been patented, one of the most significant being the sodium silicate coatings introduced around 1975. Granules as used in construction (specifically roofing materials) are defined as natural or synthetic-mineral grains smaller than gravel and larger than sand in particle size. They are used primarily for protective and decorative purposes on the weather- exposed surface of asphalt composition roofing. Development of artificial coloring techniques has made it possible for the roofing industry to provide asphalt roofing shingles in a wide variety of colors complementing the color and style of buildings. Roofing granules, as we see today, are the products of long technological evolution.

Jan 1, 1994

By J. D. Lindner, Gene E. Roark

Waterflooding operations in the Langston-Kleiner field. Young County, Tex., are described. Widespread application of formation fracturing has been practiced in both producing and injection wells. Field performance data arc cited which indicate than no detrimental effect on sweep efficiencies and that probable benefits in imectivily have resulted from the fracture treatments. I N T R O D U C I O N This paper is a report on a waterflood operation which is being carried out in the Lanpston-Kleiner field located in Young County, Tex. The oil reservoir aflected by this flood operation occurs in a Strawn sand member at an approximate depth of 3.550 ft subsurl'ace. The operators of' the project are Kleiner Estate. Turncr. Fiske. and West who are hereinafter collectively referred to as the Operators. Although the operation is unusual in several respects, the distinctive feature of this flood has been the widespread application of hydraulic formation fracturing treatments as a means to improve productivity and injectivity of the wells. It shall he the purpose of this paper to present basic information regarding the reservoir characteristics. op- craling practices, and waterflood behavior so that conclusions may be drawn concerning the effects which the fracture treatments have had on the performance of this water flood to datc. DEVELOP MENT Development of the 3,550 ft Strawn sand reservoir occurred during 1951 and 1952. The early development occurred on the Langston and Davis leases which arc in the northern region of the Operators' holdings and the wells were drilled on 20-acre proration units according to the field rules. However, studies of the economics of this program. coupled with the decision to proceed with pressure maintenance by water injection. resulted in the adoption of wider spacing in the later stages of development. This variation in spacing is apparent upon inspection of Fig. I upon which only the 3,550-ft Strawn sand producing and injection wells have been located on the Operators' properties. The development to the north of the operators leases is Ihe Garvey Strawn field and that to the south is the Taylor Strawn field. It wits determined that unitization of the leases to he involved in the waterflood program was not feasihle. Consequently. a system of offset injection wells, or lease line injection wells, was adopted from place to place as required to protect correlative rights in the program. This resulted in a dispersed array of injection and producing wells with relatively close proximity of wells along lease line areas and wider spacing toward

Jan 1, 1956

By Jaime Huidobro, Michele Hall

The desensitization of an explosives column by the transmitted effects of the earlier detonations in nearby explosive charges is of vital concern to the explosives and blasting industries. Stress waves from detonations of borehole charges have the capacity to desensitize adjacent delayed borehole charges. This desensitization can be of a transient or a permanent nature.

Jan 1, 1994