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By A. M. Taweel, M. T. Ityokumbul, A. I. A. Salama, M. W. Mikhail

The liquid-phase mixing within CANMET's Western Research Centre's (WRC) 0.76-m-diem pilot-plant flotation column was characterized using a salt tracer. The process variables studied were frother addition and, gas and liquid flow rates. The response of the column to a tracer pulse was monitored at three axial and two radial locations. The results showed that the 2-tph flotation column was well mixed. Discussed are the implications of this observation to column design and scale-up.

Jan 1, 1996

By Gu Guohua, Hu Yuehua, Zhang Qin

The flotation behavior of pyrrhotite was investigated by using ethyl xanthate as a collector. Results showed that pyrrhotite had good floatability from pH 2 to pH 11, and poor floatability when pH was >12. The flotation of pyrrhotite was dependent on pulp potential on various pH values. The potential-pH range for pyrrhotite flotation was established. Cyclic voltammeny and FTIR spectroscopic analysis showed that the major adsorption product of ethyl xanthate on pyrrhotite was dixanthogen. The intensity of FTIR signals of dixanthogen adsorption on pyrrhotite and the anode current of a pyrrhotite electrode and flotation response of pyrrhotite are correlated with pulp potentials.

Jan 1, 2005

By W. J. Schlitt, J. H. Templeton

The chemical reactions that occur within a copper-leach recovery system are discussed, and the impact on the overall acid balance is evaluated. Both oxide and sulfide mineralogy are addressed, and their effects on acid consumption, generation and solution buffering are presented. Two case studies that apply the discussed chemistry show the practicality of using a computer spreadsheet acid-balance model for the early planning and design of copper-leach systems.

Jan 1, 1998

By F. H. Deily, H. W. Lownie, E. A. Loria, L. W. Ledgerwood, M. W. 207-000-000-012 Mallett, J. E. Eckel

MANY investigations have been made of the residual gas content of iron and steel. Very few, if any, quantitative measurements have been made on the oxygen content of cupola-melted iron.' The fact that cast iron is a complex alloy rather than

Jan 1, 1957

By Gordon T. Clark

The preliminary design of four mined stations and 7.2 km (4.5 miles) of tunnels for Seattle’s light rail transit system is described. Constraints that influenced the design and options that were studied are discussed. The hilly post-glacial soft-ground geology of the Puget Sound Region pushed the alignment deep. Mined underground stations at depths up to 75 m (250 ft) and shafts with excavated diameters of 20-m (65-ft) are required. A 460 m (1,500 ft) sub-aqueous crossing of Portage Bay and undercrossing of an active 12-lane multi-level freeway were two of the more significant design constraints.

Jan 1, 2001

By Arvid Holst Mortensen

The rational exploitation of deposits for cement manufacture requires evaluation of the material, the planning of the quarrying and the right choice of quarry machinery. By using a computer for all evaluations and planning work the optimal recovery of material is arrived at and a quarry layout - and machinery is decided upon. The result will be uniform production throughout the lift of the deposits using a rationally chosen quarry equipment.

Jan 1, 1977

By M. J. Meulendyke, J. D. Purdue

Within the mineral processing industry, a range of grinding conditions exists which include semiautogenous grinding (SAG),rod milling, and conventional ball milling. Each of these mill environments presents a unique environment for grinding media, requiring the application of specific physical and chemical properties for optimum grinding media performance. The environments are characterized by varying degrees and combinations of abrasive, corrosive, and impact wear. An extensive test program has been conducted to determine the extent wear rates vary between these different applications. Test results are related to production results, ball size, and mill operating conditions.

Jan 1, 1990

By C. J. Pritchard

Productivity improvements reduced the number of continuous miner sections from seven to three while maintaining full productive capacity. So a decision was made to test an advancing tailgate ventilation system on the shortwall mining section. Having the shortwall mine its own return air system has freed the third mining section for more productive, less costly mining. The advancing tailgate has provided effective ventilation across the face and gob with acceptable pressure losses. The low-productivity, tailgate-development, continuous-miner section has been transformed into to a high-productivity, development-retreat section that is also available for long-term mine development duties, increasing mine planning flexibility.

Jan 1, 1991

The main objectives of this paper are to identify the main sources of coal dust and to investigate measures for minimisation of dust generated at these sources at the Bukit Asam open cut mine, on the island of Sumatera, Indonesia which uses a

Jan 1, 1994

By Y. S. Kim, A. Bailey

A feasibility seismic refraction and reflection field survey was conducted at the U. S. Borax Company open-pit mine, Boron, California by the writers during the weekend of March 13 and 14, 1976. This field survey was carried out as a preliminary investigation primarily for the purpose of evaluating and establishing the ability of such geophysical techniques to locate and outline the subsurface openings of the old room-and-pillar mining under the present open-pit. The value of such knowledge about the old underground workings is directly related to the safe and economical operation of the open-pit mine for the company. Although mine maps of the old underground workings are available at the mine, the extent of roof and wall cavings and the present condition of the old underground openings are unknown. Owen and Suhler (2) are the first investigators who used electromagnetic methods, Pulse-Echo System, and electric resistivity measurement to solve the problem without success. A few years later, Herzig and Owen (1) attempted to solve the problem with application of earth resistivity measurement method with unfavorable results. The U. S. Borax Company carried out an extensive study for slope failure problems of the open-pit with application of dipmeter measurements. However, the slope stability study was not correlated to the old underground openings lying under the present open-pit (3).

Jan 1, 1977

By McHaina D. M, Hardcastle S. G

A description is given of an investigation into the feasibility of using controlled recirculation of warm exhaust air into the cold intake air of underground mines during winter. Canadian mines can experience inlet air temperatures of minus 30 ¦C and less, requiring them to pre-heat their intake air. The use of controlled recirculation would reduce the inlet air quantity and thus reduce heating costs which exceed $1M on some mines.

Jan 1, 1988

By Harvey Brooks

Jan 1, 1963

By Wallace Ralston

DuRing the year of 1937, the East Texas district produced 211,194,467 hbl. of oil and marketed more than 22,329 million cu. ft. of gas; 3377 oil and gas wells were completed. During this same period 106 exploratory wells were drilled, discovering three new oil fields and one gas-distillate field. Fields East Texas Field.—The East Texas field again led the district as to production and number of wells completed. During the year, 2420 oil wells were completed, making a total of 24,382 producing wells, which produced 171,336,854 bbl. of oil, for a total of 1,156,352,834 bbl. since the beginning. During the year the average bottom-hole pressure dropped 49 lb., making the average bottom-hole pressure 1119 lb. Approximately 3500 wells are making salt water, 20 per cent of them making over 80 per cent of the water. During the month of December, the daily average production of salt water was 119,000 barrels. Talco Field, Titus and Franklin Counties.—The Talco field produced 9,780,948 bbl. of oil during the year, from 637 wells. During the year 472 wells were completed. All of the wells are pumping and 241 are making salt water. This field has followed a normal development and did not exceed the estimated number of acres reported last year. Rodessa Field, Cuss and Marion Counties.—The Rodessa field was extended about 13 miles southwest into Marion County, which added approximately 4000 acres to the field. During the year 260 wells were completed, making a total of 416 producing wells, which produced 12,646,-970 bbl. of oil. The author was unable to obtain figures for the amount of gas produced. The field has two gasoline plants, which had a daily average of 16,558,000 cu. ft. of gas during December, averaging 0.83 gal. per M cu. ft. As of Jan. 1, 31 wells were making salt water. The bottom-hole pressure varies greatly, depending upon the pay from which the well is producing. The average bottom-hole pressure from the Young

Jan 1, 1938

?ADAIR, ARTHUR C., Corp 4th Co., 1st. Training Bat., 154th Depot Brigade. ADAMS, HENRY, Major: Chemical Warfare Service. ARLUCK, A. A Headquarters, 1st Corps of Artillery. ASKIN, THOMAS B. H Ensign. BANKS, H. R., 2d Lieut Canadian Engineers. BAYLESS, G. E. S Supply Dept. U. S. Submarine Base. BELL, L. R Co. C, 302d Engineers. BELLIS, ARTHUR E., Capt Ordnance Reserve Corps. I BIRRETT, HOWARD, Lieut., Aviation Section, U. S. Signal Corps, Ellington Field. BOISE, PAUL T 2d Regiment, 24th Squadron. ?BRADLEY, CLARENCE I Convois Automobile Section 585. BROWN, GEORGE M Co. G lot Engineer Replacement Regiment. BUCKINGHAM, ALBERT U. S. S. " Coronet," S. P. 194, Section Base No. 7. BURNS J. J Co. 1-B, E. R. O. T. C. BURT, Co. B, let Engineers Replacement Regiment. ||BYERS, WHEATON B., 2d Lieut Ordnance Dept. CANTON, WILLIAM R., Sgt Headquarters Co., 80th F. A. CARSON, JOSEPH A., Capt A.S. S. R. C.' CHAPMAN, LEWIS C. Corp 29th engineers. CHETNEY, P. C., 2d Lieut 15th Bat. Headquarters Co. CHEVRILLON Louis French Red Cross. CHIDESTER, W. B., 1st Lieut 24th Machine Gun Bat. CHURCH, JOHN L., Capt 308th Engineers. CLAGHORN, D. MONTGOMERY, 1st Lieut 45th Engineers. CLAQHORN, JAMES L., Lieut Aviation Section, Signal Corps. CLARKE, ALEXANDER F U. S. Naval Aviation Service. COMINS, WALDO H. Ca t 41st Co., 164th Depot Brigade. COOK, FREDERICK A., Capt., Engineer Reserve Corps, Asst. to Div. Engr. 79th Division. COOPER, CLAUDE H. Capt C. A. R. C., 50th Artillery. COPELAND, N. R., Lieut. ||CORBY H.. G., 1st Lieut Co. D, 109th Supply Train. CORSA, BEAN, Capt Co. D, 612th Engineers. CORTESE, EMILIO Italian Army. COULDREY PAUL S., Corp British Expeditionary Forces. || CRAGIN, RODNEY S Co. E, 115th Engineers. CURRIE, JOHN M., Ca t Royal Engineers. || CUTTING, G. W., 2d Lieut U. S. Reserves, Field Artillery. V DARRINGTON, PAUL N., 1st Lieut U. S. Infantry. DAVIS, ANGUS W., Lieut-Col British Expeditionary Forces. || DAVIS, THORNTON, 1st Lieut 13th Field Artillery. ELAND, FREDERICK A., Major Engineer Reserve Corps. DOUGLAS, JAMES $ American Red Cross. DOVE, D. R., Candidate 21st Training Battery, F. A. C. O. T. C. Dover JAMES J 6th Co. C. B. DOWS, DAVID,Capt Coast Artillery, Officers Reserve Corps. || DRAKE, M. 6., 2d Lieut Headquarters Co., 325th Infantry. I || EMMERSON, E. Roy British Navy. EVERIT, RICHARD STURTEVANT Heavy Artillery Officers' Training Camp.

Jan 1, 1923

By Georg Masing

Jan 1, 1933

This paper briefly reviews the history of mine haulage trucks. It reviews producti- vity limitations with respect to size or speed. Changing haul requirements once again create the need for more flexible mechanical drive power transmission equipment. The new equip- ment however is designed to provide extended life between overhauls as compared with previous mechanical transmissions.

Jan 1, 1981

By Shrivastava P, Humphreys M, Guibal D, Deraisme J

Customer requirements concerning the final products of iron mines are extremely stringent. Because of this, there is an ever-increasing need for mine operators to monitor and strictly control the quality of their product. This quality, as measured by the stockpile grade variability, is the result of a very complex process, where natural characteristics (the orebody and its geology) are transformed through the mining technique (open pit, shovel and truck fleet, blending into stockpile). The only way to reproduce and hence to control the variability of such a system, which is composed of several interactive sub-processes, is by simulation. A complete simulation of a Hamersley Iron Pty Ltd (HI) ore deposit has been undertaken to forecast the impact and cost of various mining methods, mining schedules and product stockpile sizes on variability of chemical and physical characteristics of the products. The mining simulation was made on a conditionally simulated orebody. On a range of criteria, the simulation was considered to fulfil the objectives set and was a valuable aid to analysis of product grade variability, operating and capital costs, selection of equipment, mine scheduling and setting of product grade targets.

Jan 1, 1994

By A. B. Szwilski

The paper outlines the factors taken into account for the selection of steel arch supports. The results are based on experience using the long wall system of coal mining where roadway closure can be extreme. Results of tests on scale-model steel arches and full-scale yield elements are also presented.

Jan 1, 1979

By G. E. McClelland

During the 1970?s, the Bureau of Mines investigated a particle agglomeration technique for improving the flow of leaching solution through heaps of clayey or crushed, low-grade gold-silver ores, wastes, and tailings. This technology has been adopted on a broad scale by the precious-metals-processing industry. This report presents information on five commercial operations that have benefited from agglomeration technology and that represent a cross section of current heap leaching practice. The technology is cost effective because of decreased leach times and improved precious metal recoveries.

Jan 1, 1983

Jan 1, 1951