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By D Goel

India, the second-largest steel manufacturer globally, achieved crude steel production of around 126 million tonnes (Mt) in the last financial year of April 2022 to March 2023 (FY23), against an installed capacity of 162 Mt. In its National Steel Policy, 2017, India has undertaken targets to take the crude steel production capacity to 300 Mt by 2030–2031 and production and demand to around 255 Mtpa, also by this deadline. The blast furnace-basic oxygen furnace (BF-BoF):electric arc furnace-induction furnace (EAF-IF) ratio in 2022 was at 44:56.

Sep 18, 2023

By Denis Racicot

"L'Abitibi québécois a produit essentiellement de l’or, du cuivre, du zinc et de I' argent, ainsi que de faibles quantités de nickel, de plomb, de molybdène, de bismuth, de lithium, de fer et d’amiante. Depuis l’ouverture de la mine Horne en 1927, cent-cinquante mines ont contribué à la production de 1 420 tonnes d’or de 4,1 millions de tonnes de cuivre et de 4,7 millions de tonnes de zinc. Les productions minières annuelles ont été d'importance variable: des records de production ont été établis en 1955 pour I' or avec 35 tonnes et, vers 1965, pour le cuivre, le zinc et la quantile globale de minerai extrait avec respectivement 130,000, 275 000 et 13 millions de tonnes. Deux dépressions généralisées ont eu lieu, l’une vers 1946 et l'autre, a lafin des années soixante-dix. Des ralentissements de la production ont été observes pour le cuivre en 1953 et le zinc en 1959. Depuis le debut des années quatre-vingt. I' or et, de façon plus irreguliere, le zinc sont en progression, landis que le cuivre, malgre une hausse en 1983. pour suit son dec/in.La teneur de récupération des mines d’or est demeurée régulière et n’a subi qu’une faible diminution au cours des quarante dernières années. Célie du cuivre a diminué d'environ 50% dans la même période, landis que celle du zinc a subi d’import antes variations, aussi bien positives que négatives. Près des trois quarts des mines d'or ont une durée de vie inférieure à 12 ans et la distribution des tonnages de minerai extrait montre un maximum pour la classe de 100 000 à 1 million de tonnes. Du cote des mines de métaux de base, la durée de vie est plus étalée et les volumes de minerai ont une occurrence maximale dans la classe de 1 à 10 millions de tonnes.Concernant la distribution géographique de la production minière dans l'Abitibi québécois, le camp minier de Rouyn-Noranda vient en tête pour l’extraction de minerai et la production d’or et de cuivre. L’est sui vi par le camp de Val d'Or pour le minerai et l’or, landis que le camp de Chapais-Chibougamau occupe la deuxième place pour le cuivre avec une production équivalence a 60% de celle de Rouyn-Noranda. Le camp de Cadillac-Malartic suit de tres pres celui de Val d'Or pour ce qui est de I' or. Finalement, dans le casdu zinc, le camp minier de Joutel-Matagami domine largement avec une production qui a connu un développement accélère depuis 1963. Une analyse pré liminaire de ces données indique qu' i/ subsiste unpotentiel encore élevé de production d'or, décuivre et de zinc dans I' Abitibi québécois. ABSTRACTThe Quebec portion of the Abitibi belt has essentially produced gold, copper, zinc and silver, as well as some small quantities of nickel, lead, molybdenum, bismuth, lithium, iron and asbestos. Since the opening of the Horne mine in 1927, one hundred and fifty mines have produced 1420 tons of gold, 4,1 millions tons of copper and4,7 millions tons of zinc. Annual mine production has fluctuated: production records were established in 1955 for gold with 35 tons, and around 1965 for all extracted ore copper and zinc with respectively 13 millions, 130 000 and 275 000 tons. Two main recessions have occurred, the first around 1946 and the second during the late seventies. Cut backs in copper and zinc production occurred in 1953 and1959. Since the beginning of the eighties, gold production and to a lesser extent zinc production have been in progression. Except for a small jump in 1983, copper production is still declining.The average recuperation grade of gold mines has been quite steady and has only slightly diminished in the past forty years. The average copper recuperation grade was halved during the same time interval. For zinc there have been important ups and downs. At least three quarters of gold mines have an average lifespan of 12 years the tonnage distribution shows a peak in the 100 000 to 1 million tons class. Base metals mines show a more widespread life expectancy and have a tonnage peak in the 1 to 10 millions tons range"

Jan 1, 1990

By E. P. Youngman

The mining laws referred to by those who furnished the reports mentioned in the preceding paragraph are : General Austrian Mining Law of 1854 and the Law of 1868 , which prescribes for Hungary (as well as for Transylvania ) the full text and decisions of the General Austrian Mining Law; Government Decree 18346 , 1859 ; Parliamentary Decree of 1861 ; the Law of 1871 ; the Commercial Code , Law 37 of 1875 ; the Industrial Lar of 1884 ; the Law of 1386 ; the Decree of the High Court of Justice , 5540 , of 1399 ; Laws 6 and 7 of 1911 ; Law of 1921 ; Laws 23 and 24 of 1922 ; Laws 5 and 21 of 1927 ; and Law 40 of 1928. ( Lev 21 of 1927 and Law 40 of 1928 are labor laws . ) A compilation of the mining laws of Hungary , " Magyar Banya Jog , " or the " Hungarian Mining Law, " was made use of in part . This volume is the second edition of a school textbook , which ras prepared by Dr. Bela Balkay and Dr. Imre Szeoke , and which was published by the Apollo Press ( V. , Sas -utca 13 , Budapest ) in 1909 .

Jun 1, 1931

By Robert Isaac Williams

The Questa mine is located in northern New Mexico on the western flank of the Sangre de Cristo Mountains about 75 miles north of Santa Fe and ranges in elevation from 6,800 to 10,000 ft. GEOLOGY The rocks of the area are Precambrian metamorphic rocks covered by Tertiary extrusive andesites and rhyolites and intruded by Tertiary granitic rocks. These Tertiary intrusives are localized in an east-west belt about 20 miles long and 2 miles wide, extending from Questa to Red River. The Questa orebody is associated with a north-trending aplite intrusive about 3/4 mile wide and 1 3/4 miles long. In the area of mineralization, the metasomatism of aplite has produced a mottled porphyritic rock. This hybrid rock has caused much of the controversy about the Questa mine intrusive. The orebody is essentially monomineralic and consists of numerous closely spaced molybdenite veins varying in thickness from ' 'paint" to 3 in. and occurring in both the andesites and the intrusive. In the intrusive the veins are often siliceous. Common alteration minerals associated with the molybdenite ore vary with the original composition of the rock. The alteration of the aplite has produced phenocrysts of orthoclase, albite, oligoclase and biotite; veins of quartz, orthoclase, and biotite; and graphic myrmekitic intergrowths of feldspars and quartz. In many places near the contact, the andesite is indistinguishable from the metasomatized aplite. The dominant alteration in andesite, however, is the development of fine-grained biotite with apatite, rutile, and sphene.

Jan 1, 1969

By L. C. IlsLey

[In 1922 a conference of representative coal-mine operators, cable manufacturers, mining-machine manufacturers, and representatives of the United States Bur eau of Mines vas held at the Pittsburgh Experiment Station, regarding suitable cables for use with permissible raining machines. This conference recommended that the Bureau investigate rubber-sheathed trailing cables in order to obtain specifications for tests leading to approval for rise with mining machines. Effective until such time as an investigation could be made, the bureau asked the several manufacturers of approved mining machines to recommend cables for wise with their machines. In general the Cables recommended tentatively approved. Arrangements for the tests were completed in 1927. Concentric-type cables were investigated first, and Reports of Investigations, Serial No. 2909, covering the tests, was issued in January, 1929.]

Jan 1, 1929

Land is of extreme importance to citizens of Papua New Guinea and is fundamental to most of their customs and values. Because of this, matters to do with land cannot easily be separated from other matters to do with the community. Good relation-ships with landowners and the community surrounding a development are, indispensable ingredients that -must flavour and colour the entire ;operati on .

Jan 1, 1994

By N. J. Keys, B. Barlin

Operating properties of Bancroft Mines Ltd. are in the Western Province of Northern Rhodesia, just south of the Katanga border and at the north- western end of the Rhodesian Copperbelt. The concentrator, above, was commissioned in January 1957 to treat 150,000 tons per month of ore derived from the nearby Kirila Bomwe South orebody, and the Konkola orebody eight miles away. The Konkola orebody is comparatively low grade and mining was discontinued there in early 1958. Development work on the new mine at the Kirila Bomwe North orebody commenced in 1959. Today, the plant treats approximately 150,000 tons of ore per month from the Kirila Bomwe South orebody and development ore from the north orebody. Ultimately, 100,000 tons of ore per month will be produced from the north orebody.

Jan 9, 1963

By K. E. Stanfield

One of the initial projects under the oil-shale research and development phase of the Synthetic Liquid Fuels Act, Public- Law 290, 78th Congress, approved April 5, 1944, was a survey of oil shales of the United States for the selection of a site for an oil-shale demonstration plant. The oil shales were assayed by the conventional Bureau of Mines retort method proposed by Karrick and described by Guthrie in a more recent publication. From previous experience and that had in making these assays, it became evident that the assay method should be modified or replaced by a more satisfactory one. There are several outstanding objections to the Bureau of Mines oil-shale assay method: (1) the oil yields are frequently smaller than those obtained by other types of assay equipment and by commercial retorts; (2) the assayed oil yield represents only a portion of the organic matter in the shale, which under more favorable conditions, may, Jae converted, more completely into oil; (3) the retorting procedure is controlled mainly by trial-and-error methods; and (4) the assay requires approximately 6 hours for completion.

Jan 1, 1949

The design and selection of components for belt conveyors is a well known procedure and many handbooks, catalogues and design manuals offer a wide range of detailed information which can be applied to most of the known conveyor problems. The aim of this paper, however, is to investigate the various methods of conveyor drive configurations, and incorporate the latest technical achievements in the control systems, particularly for high capacity conveyor systems carrying ore from pit to processing plants where the lowest maintenance, operating and initial costs are of major importance. Past experience has proven that multi pulley drives can reduce initial capital cost of a conveyor; this leads to the need for better torque control during startup, running, stopping and load sharing. Many methods of torque control are available and have been used in the past. All types have their advantages and disadvantages and must be considered when designing a conveyor or conveyor system. However the recently developed solid state electronic soft start controls utilising AC squirrel cage induction motors are gaining acceptance, especially for a conveyor system where the same control and logic system can be used to transmit startup commands to more than one

Jan 1, 1978

By Calvert D. Iles

Open-pit mines in the US and throughout the world are typically characterized by increasing operating costs and decreasing ore grades. Thus, companies must continue to improve their use of human and technological resources to remain competitive in the marketplace. Duval Corp. has historically been very sensitive to mining costs, in part because of relatively low grade copper-molybdenum ore bodies. These concerns have resulted in three haulage system generations at the 218 kt/d (240,000 stpd) Sierrita-Esperanza open-pit mine south of Tucson, AZ. Each generation has exceeded the performance of the one replaced. The latest system of portable crushers and conveyors reduces hauling costs by combining both hardware and technique. Savings are achieved not only bysubstituting conveyors for haul trucks, but also by permitting the crusher-convey or system to closely follow mining as the pit deepens and/or mining areas change location. The Duval system is capable of easy and inexpensive relocation in varying site configurations in relatively short time periods. Its implementation in active mining areas results in minimum disruption to both the mine operation and mine design. This haulage concept allows the mining engineer maximum freedom to design an open pit for profit rather than for equipment. Maximum savings with a portable system are achieved by minimizing truck haulage costs. At Sierrita, for example, the yearly estimated operating cost savings for each thousand feet of +10% truck ramp replaced by conveyors is about $1 million per portable crusher. A savings of $30 million could be achieved fora three-portable system overa 10 year period simply by reducing the average truck Iiftto the crusher by 30 m (100 ft), There is also the added capital expense of buying trucks to cover the additional 30 m (100 ft) of lift. Relocation costs are an important consideration in a portable system. Direct costs can become a significant operating expense if frequent relocations are necessary to take full advantage of potential haulage cost savings. A site preparation cost of $375,000, for example, would add an additional operating cost of 2.8¢/t(2.5¢/st) for a system handling 13.6 Mt/a (15 million stpy), assuming one move a year, In addition to the direct cost of site preparation, such as installation of retaining walls, apron feeder slots, and equipment pads, there is the cost of site renovation after abandonment. Indirect relocation costs, while less tangible and more dependent on specific mine design and scheduling, can be of significance. A slowdown in the mining rate or a less efficient mining plan can result from a site not being immediately available for mining after abandonment. Conversely, mining in narrow areas can be adversely affected if two or three month lead times are required for site preparation.

Jan 4, 1983

By Xun Zhang, Hang Qiu, Andrea R. Gerson4, Shaomin Lei, Yubiao Li, Yu Meng, Zhenyu Pei, Min Lin

Efficient separation of trace muscovite from the surface/interface of quartz grains was accomplished during oxidizing calcination and catalytic pressure leaching of the hydrothermal quartz. Experimental results suggest that 98.97% or more of the muscovite was separated when quartz sand was calcined at 900 °C for 5 h and then leached by hydrochloric acid and ammonium chloride solutions as substitutes for leaching agents containing fluorides. The chemical processing techniques show high selectivity in purifying quartz sand by transforming mineral muscovite into active structures during oxidizing calcination, and then dissolving the active substances during catalytic pressure leaching

By L. M. Luckevich

Gypsum is a product from the neutralization of sulfuric acid by lime or limestone. This paper will discuss specifications for gypsum used in wallboard, cement and agriculture and the factors affecting its utilization potential. Process conditions during the neutralization which enhance or inhibit utilization potential will be included. In addition, this paper provides a technical and economic perspective of the gypsum industry in North America with a view to the factors affecting the utilization of synthetic gypsum in traditional applications. Current production and consumption of natural and synthetic gypsum in Nonh America are described and the impact of their differences on utilization options are discussed.

Jan 1, 1996

By H. P. Greenwald

For some years past the Safety in Mines Research Board of Great Britain has been making an intensive search for. materials that would be more efficient than rock dust and that could replace it wholly or in part as a moans of preventing the prorogation of coal-dust explosions in mines5/ In the course of this work several rock ducts and numerous inorganic compounds were tested. The results place incombustible substances in two main groups; (1) Those whose effect in suppressing the combustion of coal dust is proportional to their capacity for absorbing heat, and (2) those that shoo much higher effectiveness than would be expected from their heat capacity. The first group includes several inorganic compounds and materials commonly ground for use as rock dust, such as shale, gypsum, and limestone. Outstanding examples of the second group are compounds of the halogens6/ with the alkali metals,7/ especially potasium and sodium8/. British investigators term those salts "inhibitors" because it is assumed that their presence has a hindering or inhibiting effect on one or more of the chemical reactions that together constitute combustion. In other words, the action of an inhibitor is postulated as chemical rather than physical; theoretically, the effect is to prevent liberation of energy instead of to absorb energy already liberated.

Jan 1, 1940

During heap leaching of secondary copper sulphide ores operated at low heap temperatures and high levels of leach solution salinity, copper recovery is usually unsatisfactory, due to a slow chemical and bacteriological leaching of the covellite minerals either formed from leaching of chalcocite or naturally occurring in ores. A laboratory test program was conducted to investigate the effect of leach solution temperature in the range of 20 to 50°C on copper extraction during stirred reactor, bottle roll, and short column leaching of fresh or heap leached secondary copper sulphide ores. It was demonstrated that increasing heap temperature is an effective approach for improving recovery of copper from secondary copper sulphide ores. A review of the technologies available for heating heap leach solution or decreasing solution salinity to improve copper recovery from secondary sulphide ore indicates that an integration of copper concentrate pressure leaching with heap leaching is potentially a cost-effective approach. A copper flotation concentrate sample was tested through pressure oxidation with the use of heap leach solutions of varying strengths for the repulping of the concentrate in order to examine its effect on pressure oxidation performance. The test results indicate that use of heap leach solution of high salinity in the pressure oxidation process does not cause a negative impact on the process performance for copper extraction, sulphide oxidation, and recovery of gold (if present) from pressure leach residue, and has additional advantages of removing the bacterially inhibitory aluminum from heap leach solution and generating more acid and ferric iron in the pregnant leach solution. A flowsheet configuration for full integration of the copper concentrate pressure oxidation with heap leaching of secondary copper sulphide ore is proposed and discussed.

Jan 1, 2014

By R. F. Domagala, M. Hansen, D. J. McPherson

On the basis of metallographic analysis, incipient melting data, thermal analysis work, and X-ray diffraction, phase relationships in the 0 to 50 atomic pct alloy content were carefully resolved. Phase relationships in the higher alloy content regions were outlined. A single intermediate phase, peritectically formed, of the form ZrX2 was established in each system. A eutectic and a eutectoid were found in the zirconium-rich region of both systems. Appreciable solubility of molybdenum and wolfram was found in ß zirconium, but only a slight solubility in a zirconium. PREVIOUS work on these systems was limited to X-ray investigations of the intermediate phases1, 2 and preliminary surveys of the zirconium-rich alloys." The diagrams presented were determined principally by metallographic, thermal analysis, and incipient melting techniques. In accordance with the Atomic Energy Commission contract requirements, phase relationships up to 50 atomic pct molybdenum or wolfram were carefully resolved, while only a limited amount of work was done to outline the 50 to 100 atomic pct alloy region. A description and analysis of the metals used in the preparation of alloys for this study are included in Table I. A "low-hafnium" zirconium crystal bar, produced by the decomposition of a volatile iodide onto a hot filament, was employed for these studies. Westinghouse "Grade 3" crystal bar was used for all alloys. The zirconium, as received, was coated with corrosion product from a standard autoclave test by which its grade designation is determined. This was removed by a sand-blasting and HF-HNO, pickling technique developed by the Atomic Energy Commission. The bars were cold rolled to approximately 1/32 in. sheet, pickled for iron removal, sheared to 1/4 in. squares, washed with acetone, and stored for furnace charge. Molybdenum sheet. 0.003 in. thick, 0.001 to 0.005 in. wolfram wire, and M in. wolfram rod crushed to granular form, from Fansteel Metallurgical Corp., were used as alloying stock. Melting Procedure A nonconsumable electrode arc furnace identical to that described in detail by Hansen et al.4 was used. The source of power for melting Zr-Mo alloys was a 400 amp dc welding generator, while a 900 amp dc generator was used for preparing Zr-W alloys. Electrode tips of the same material as the alloy addition were employed in both systems, i.e., molybdenum tips were used for Zr-Mo alloys, and wolfram tips for Zr-W alloys. This precluded any possible electrode contamination during arc melting. Ingots of 20 to 30 g of Zr-Mo alloys were melted under high purity helium in the cavity of a copper block insert in a spun copper crucible. Homogeneity was insured by remelting all ingots four to six times without opening the furnace. Due to the large difference between the melting points of wolfram and zirconium, direct melting of the charged metals as above generally yielded ingots containing unmelted wolfram particles. This was overcome, after many variations in technique, by melting a pure wolfram charge at high power levels (700 to 900 amp) and slowly adding zirconium to form a master alloy. Such master alloys were sectioned and remelted several times, then crushed to serve as melting stock for alloys of lower wolfram content. Master alloys containing 26, 50, 52, 70, and

Jan 1, 1954

By Nadir Ansari, Brian W. Wilson, Marina S. W. Li

"A hybrid Deep Mixing (DM) shoring system was recently constructed for a high-rise development in downtown Vancouver, British Columbia, Canada for the temporary support of a five-level basement excavation. The site is bounded by an existing bridge off-ramp structure along its longest side and by city streets on the other two sides, which formed a truncated triangle in plan. A conventional secant pile wall was installed along the longest side, about 380 ft (116 m) in length, of the site. Hybrid shoring walls (HSW) 1 and 2 were installed along two shorter sides with each being 235 to 246 ft (72 to 75 m) long. HSW 3 completed the excavation support system along the shortest side with a length of about 55 ft (17 m). Cutter soil mixing (CSM) was proposed by the excavation and shoring design-build team in lieu of conventional secant piling. CSM was the preferred method to construct the infill panels between soldier piles because of the speed at which the shoring system could be constructed in the variable fill, peat, wood waste and overburden. Design ConsiderationsTo minimize the impact on buried utilities along the outside perimeter of the excavation, the temporary shoring was designed to limit the lateral displacements to less than 0.8 in (20 mm). Factors taken into consideration for shoring design included the lateral earth pressures from the fill and native soils, groundwater pressures, temporary construction loads (e.g., crane or heavy plant/equipment), and permanent structural requirements. The subsurface conditions at this site typically consisted of fill (cohesive and granular), overlying peat and/or wood waste, overlying clayey silt to sandy silt, overlying weathered to dense to very dense clayey silt till to sandy silt till with silt layers. Localized, perched groundwater was observed within the fill, peat, wood waste and sandy silt layers above the dense till."

Jan 1, 2017

Jan 1, 1917

By Reeves I. And Farquhar J, Pearce S

The irregular shape of the Rosebery orebody, coupled with the inconsistencies in grade over short strike lengths, has meant stoping blocks have had to be small to combat dilution and stability problems. In the past, each lens was divided into regular block sizes and developed up to five years before production commenced. There were two major drawbacks to this practice; firstly, existing development deteriorated over time therefore requiring rehabilitation prior to production. Secondly, the pre-determined blocks could not be easily changed to incorporate changes in mining technology or economic circumstances. Bearing these problems in mind, it was evident that any new lens development had to be designed to allow maximum flexibility. The lens being currently developed is J lens. It represents approximately 50 per cent of the current reserves tonnes, and 65 per cent of the zinc metal. Its importance to the mine's future cannot be over emphasised. At its core the lens is up to 25 m thick at grades of over 30 per cent zinc. The practice of dividing the orebody into levels and sublevels, with consequent crowns was no longer acceptable because of restrictions in stope design and potential loss of ore. To assist in the development planning of J lens, a geostatistical block model was applied in long section to graphically represent the lens. Areas of high zinc concentration, as well as zones of uneconomic material were identified by using the model. This has meant that the development could he targeted, enabling stope delineation to occur in the lens without significant ore loss. Because of limited development resources, and the need to bring J lens on-line in the near future, the development strategy has had to focus on 'just-in-time' principles, rather than accessing the whole lens from bottom, and progressing upwards. Tight development schedules have required individual stoping block to be developed on such factors as grade and available tonnes rather than as a vertical sequence.

Jan 1, 1993

By H. Scott-Russell

Ladies and Gentlemen. It is my great pleasure on behalf of The South African Institute of Mining and Metallurgy and The Geological Society of South Africa to welcome you to the 15th CMMI Congress and to Southern Africa. It is a great honour to be hosting this event and we have been looking forward to it for a long time. I am sure the technical discussions and visits will be of great value, and I am confident you will return with pleasant memories of places and people in South Africa and neighbouring countries. The theme of this Congress, Resources and Technology', is appropriate for discussions on the ways and means of going forward in the minerals industry to create the employment and wealth so sorely needed in this region. The technical programme will give mineral industry professionals from different parts of the world the opportunity to share experience and expertise for the purpose of making operations more productive, safer and environmentally acceptable to the world at large. Delegates will be exposed to current technical developments by means of 133 papers prepared for the congress: 30 on geological subjects, 45 on mining, 29 on extractive metallurgy, and 29 in the field of metals technology.

Jan 1, 1994

THE SOUTHWEST MINING SECTION of the National Safety. Council held a well attended two-day conference at Globe, Ariz., March 19 and 20; followed by two days of mine-rescue maneuvers at the Old Dominion mine in cooperation with the Globe-Miami District Mine Rescue and First Aid Association and the U. S. Bureau of Mines. C. L. Colburn of the Bureau had general charge of the arrangements and was chairman of the conference. All sessions were held in the Old Dominion Library. The program of papers was as follows: MINE FIRE PREVENTION AND FIGHTING What to do in Case of a Mine Fire. / Chas. A. Mitke, Consulting Mining Engineer, Bisbee, Ariz. Gunnite as a Fire Preventative. W. C. Browning, General Manager, Magma Copper Co., Superior, Ariz. Chemical Engineer's Part in Fire Fighting. Dr. L. H. Duschak, Consulting Chemical Engineer, San Francisco, Cal. Mine Fire Drills. A. C. Stoddard, Chief Mining Engineer, Inspiration Consolidated Copper Co., Inspiration, Ariz. Notes on the Installation of Fire Fighting Equipment in Mines. Benjamin F. Tillson, Assistant Superintendent, New Jersey Zinc Co., Franklin, N. J.

Jan 5, 1923