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Study on Influence that Styrene-Phosphoric has on the Surface Property of Rutile Minerals

Sep 13, 2010

By Frank Hagar, George M. L. Robinson

INTRODUCTION Mine waste monitoring and management is essential when the industry is being required to accept the environmental liability for all generated, stored and disposed solid and hazardous waste. Environmental regulations mandate the operator to minimize waste production while requiring the operator to cleanup existing contamination. Since these requirements are being enforced, many operators do not have a clear under- standing, whether their existing operation will or could be required to adopt remedial plans to mitigate off-site contamination impacts. The following methods, using conventional and advanced geostatistical methods, provide a tool to make appropriate assessments whether existing or potential contaminant issues are present. BACKGROUND Generated solid wastes from mining operations are currently exempt from Solid Waste Disposal Act (SWDA) Sub- title C (RCRA), statutes and promulgated regulations, however, compliance with SWDA Subtitle D statutes and regulations is required. In order for the mining operator to be exempt from hazardous waste regulations, the operator must demonstrate that generated waste does not have hazardous waste characteristics. In many instances the operator will be able to use statistical tools and their existing data to determine whether their site could be a potential hazardous waste liability. METHODS The following statistical and geostatistical methods can be used to determine whether existing wastes could be a regulatory concern. The following presents a brief discussion of standard statistical methods and discusses, in greater detail, how advanced geostatistical tools can be used to define potential waste issues. The following will discuss how data can be screened, "Data Filtering and Reporting"; how data can be evaluated using "Conventional Statistics"; followed by a detailed discussion o f "Geostatistical and Estimation Techniques" and "Statistical Modeling". Data Filtering and Reporting Data filtering is the simplest, but potentially the most powerful statistical tool because data can be easily sorted to meet regulatory reporting requirements. Filtering includes unions and intersections of data such as date, maximum and minimum values of one or several variables. Using the data base presented in "Mine Waste Data Base Management Procedures", Robinson and Hagar, 1987, an example of a filter group is presented.

Jan 1, 1987

By S. M. Shelton

SINCE the Saar started. the real progress in scrap-metal recover is in the change of point of view regarding secondary metals. The tendency had been to regard scrap as the normal outgrowth of obsolescence, fluctuating somewhat from periods of depression to periods of prosperity. but nevertheless an unwieldy economic factor more to be contended with than embraced. Now, metals above the ground are being looked upon as semi-permanent reserves or stock piles in various stages of repeated use or revolving life cycles. The change in point of view is due to the forced realization that domestic supplies of new metals are limited and many foreign sources are at least temporarily closed. The stock piles must be cultivated. The reserves must be made more nearly permanent. Steps are being taken : (1) develop methods for recovery of scrap metals heretofore not recovered, and (2) restrict strategic metals to uses ensuring a large percentage of re-use, which in turn means substitute materials in the dissipative uses.

Jan 1, 1942

By Albert Roberts

Summary In response to a growing intolerance towards ground vibrations and noise as environmental pollutants the engineer must consider the effects of his operations as they are likely to be judged subjectively by the public at large. Much work has been done on the study of vibration damage to structures, but the damage criteria normally applied do not take into account any resonance effects, nor do they embody any subjective criterion. Mu1tiple criterion techniques of subjective appraisal have proven to be of value .in the assessment of environmental comfort in relation to ventilation, air conditioning, and lighting. One such scale, the Reiher-Meister Scale, has also been applied to ground vibrations and noise, and an attempt has been made to correlate this scale with objective criteria, using the parameters of frequency and displacement. This paper quotes examples and compares ground vibrations resulting from blasting, the operation of, vibrating and impact-hamner pi1e drivers, forge hammers, and railway and road traffic. The Reiher- Meister Scale was applied to a subjective-objective correlation in relation to vibrations from railway traffic and gave results which did not conflict with experience.

Jan 1, 1971

By E. Allaine

Carbochlorination kinetics of pure MoO3, Nb2O5, Ta2O5 and V2O5, by Cl2+CO+N2 gas mixtures was investigated between 380 and 1000 °C. Standard free energy of carhochlorination reactions and phase stability diagrams of these refractory metal compounds were calculated. The influence of total gas flow rate, temperature, reactants partial pressures on the reactivity of these oxides were investigated. The apparent activation energies were found to be about 83, 75, 110 and 100 kJ/mole below 650°C for MoO3, Nb2O5, Ta2O5 and V2O5, respectively. Above this temperature, the Arrhenius plots exhibit a rate anomaly attributed to thermal decomposition of COCl2 and/or structural changes of these refractory metal oxides. The apparent reaction order of carbochlorination of these oxides with respect to Cl2+CO was determined. For these refractory metal oxides, the reaction rate was maximum for a Cl2/CO ratio of about 1 in the chlorinating gas mixture. Results of carbochlorination of these oxides are compared and discussed.

Jan 1, 1995

By D Moss, P Ganza

There are continuing developments in underground narrow vein mining, from innovative mining methods using low-profile equipment to adaptations of current mining methods using equipment such as road-headers. The development of new mining methods and mining equipment has one purpose in mind û to extract narrow reef orebodies keeping dilution to a minimum, whilst maximising mining recovery. Achieving this will increase the head grade of the ore mined and reduce the tonnes delivered to the mill. Narrow vein mining in Australia has been limited to traditional hand held or mechanised drill and blast methods using existing æoff the shelfÆ equipment. Numerous trials have been undertaken using rock cutting technology and lower profile equipment, but these mining trials have not resulted in the full implementation of any new mining method or the adoption of low profile equipment in narrow vein mines as an accepted mining methodology. Mine operators in Canada and South Africa have teamed up with a number of equipment manufacturers and have taken steps to further mechanise and automate the mining of narrow vein orebodies, in particular to increase safety and productivity. The challenge to Australian narrow vein mining projects is to capitalise on work undertaken by overseas mining companies and equipment suppliers and to investigate the adaptation of low profile coal mining machinery to specialised metalliferous mining. With the inevitable fall in metal prices, it is necessary for Australian mine owners and mining contractors to apply these specialised methods and equipment to make narrow vein mining profitable.

Jan 1, 2005

By completing a double-track railroad cut-off, involving a large volume of cut and fill, in addition to a half-mile bridge spanning an important French river, engineers in the zone of the Services of Supply have opened up a route by means of which hours of valuable time are being saved in transporting men and materials to combat areas. Its most valuable feature is that it provides a means for by-passing a certain city where several, French railroad lines converge and where, consequently, congestion of traffic has been responsible for delayed train movements. To avoid a double-track turnout, which would have involved a cross-over cutting one of the French tracks, the two track connections of the cut-off are taken off from opposite sides of the French right-of-way. This involved running one of the new lines of the cut-off out from the main line track on a fill to a point where it could be brought back and over the French track on a steel girder bridge. Beyond this bridge the two tracks of the cut-off converge and straighten out in the standard type of double-track construction. The new cut-off is about 5 3/4 mi. (9 km.) long and has required 160,000 cu. yd. of cut (122,329 cu. m.) and 414,000 cu. yd. (316,527 cu. m.) of fill. In the biggest continuous fill a-yardage of 180,000 has been placed; the road-bed in this section-being-about 40-ft. (12 m.) above the original ground surface. The bridge portion of the cut-off, 2190 ft. (667.5 in.) long, is made up of ninety-nine 14-ft. (4.3 m.) timber spans and sixteen 50-ft. (15.3 m.) steel girder spans. This is the longest bridge which engineers of the American Expeditionary Forces have built in France. The timber spans are supported by pile trestle bents, while the longer steel girders rest on clusters of 43 piles. Two pile drivers of the steam-hammer type worked from each -end of the bridge toward the center of the river, while a drop hammer worked westward from the shore end. In this structure nearly two thousand piles 50 ft. or so in length had to be driven.

Jan 12, 1918

By G. H. Hope

"Pamour Porcupine Mines of Timmins, Ontario operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the area. The area milling concept was adopted by Pamour in 1971 and has been used successfully since then. The purpose of this paper is to discuss the advantages and the problems of area milling. Pamour Porcupine Mines Limited operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the Porcupine region. The area milling concept was adopted as the route to survival for Pamour and has worked successfully. HISTORICAL BACKGROUNDProduction of gold from the Porcupine region in Northern Ontario started in the early 1900's and has been continuous since that time. Some of the major operators were companies such as Mcintyre, Hollinger, Dome, Pamour, Paymaster and the list goes on. An underground survey would reveal hundreds of miles of drifts and raises. The main group of mines extends from South East of Timmins to the Pamour Mine, 15 miles to the east. During the lean years of the sixties when gold prices were low, labour costs were rising rapidly, and ore grades were dropping, many of the area mines closed down their operations."

Jan 1, 1981

By P. Reyes

The Codelco Chile El Teniente Division Caletones Smelter has an objective to smelt 1,250,000 tonnes per year of copper concentrate. This is a great challenge for the smelter facilities and particularly for the acid plants. The analysis ensuring that there are no obstacles to achieve the production capacity was of great importance. Therefore a series of activities were undertaken as well as studies dedicated to reach the target. This paper presents work focused on a fluid dynamic study, translated in an operation methodology of integrated handling of the smelting and converting gases with the objective to optimize the gas flow and S02 concentration. The optimization should be done employing the current installations, equipment and instrumentation and/or minor modifications. In the first part of the work the condition of the instrumentation involved in the gas handling was checked, improvements determined and the corresponding corrective actions were carried out. The proposed operation method consists of operation of the Cleaning Gas Plant 2 (TC' s gases) and operation of Gas Cleaning Plant 1 (the remaining gas plus the gases from CPS). The implementation of the operation method involves the modification of the valve of the gas into the duct to plant 1 from On to Off to modulate flow. After modification a three days test was carried out. To evaluate the tests, a "Sulphur Capture" indicator was used. During the test the behaviour of the effluent treatment plants was closely examined. No problems or unusual operating conditions were observed. The reduced flow of gas to Gas Cleaning Plant No. 1 permitted the start up of the 2nd test day treating most of the gas received by Gas Cleaning Plant No. 2. The operation was carried out with the limitation not to increase the effluent pond level, which was maintained constant.

Jan 1, 2007

OVERVIEW OF PRESENTATION ? What is LMI ? Who uses LMI and how? ? Value of LMI to the Mining Industry ? Mining Industry Workforce Information Network (MIWIN) ? The Challenge: Forecasting the future in uncertain times ? Results: Hiring requirements in the next decade ? Results: Occupational information ? Next steps

May 1, 2009

By J. G. Groppo

Eastern U.S. oil shale contains approximately 10 to 12 gallons of oil per ton and 7 to 10 percent pyritic sulfur. Physical beneficiation of these low grade shales using froth flotation provides a high grade material which will make extraction of oil more economically attractive. The Alabama oil shale used in the present study contained 16.46 percent organic carbon and 14.5 gallons of oil per ton as determined by Fischer assay. Liberation size of the kerogen was estimated at 10 /-Lm. 'Ken-Flote' column flotation technology provided a high grade concentrate containing as much as 60 percent organic carbon, however, carbon recovery was about 60 percent. Carbon recovery was improved to 75-85 percent while maintaining concentrate grades in excess of 40 percent carbon by providing longer retention time in the column which facilitated effective bubble-particle collision and attachment.

Jan 1, 1993

By Lucia Kuizon

The Miranda Pine Roadless Area Review and Evaluation (RARE II) study area (No. 5114) comprises 12,600 acres (5,100 ha) in Los Padres National Forest in Santa Barbara County, California, about 15 mi (24 km) east of Santa Maria (fig. 1). Mineral investigations are made by personnel from the U.S. Bureau of Mines on National Forest lands identified as Further Planning Areas in the RARE II program. The Bureau of Mines reviewed literature, mining claim records, and production files; examined the study area; and sampled mineral properties where appropriate.

Jan 1, 1983

By Bromley JC

Eimco Great Britain, a division of Baker Mining Equipment Company, was contracted to develop a hardrock tunnelling machine in conjunction with British Coal. The objective: a machine to cut rock up to 170 MPa compressive strength yet retaining the flexibility of roadheader type machines. This flexibility to encompass mobility, wide range of excavation shapes and sizes, simplicity of design and use, compact size, and efficient cutting operation. Current roadheaders operating in hard material are characterized by: 1. Severe machine vibration 2. Bouncing of the boom away from the rock 3. Very high pick wear 4. Inability to sump head in bad floor conditions The reasons for this poor performance can be attributed in part to: 1. High speed of cutting head rotation 2. Inability to hold boom against rock while cutting variable hardness strata. To overcome the problems described, a new articulation method was developed utilizing four hydraulic rams to "lock" the boom in position on one axis and four hydraulic motors to rotate the boom for cutting via a turret arrangement. The slide mounted turret is hydraulically advanced for sumping into the face, independent of the machine base. To transfer cutting forces back to the rock, the machine base is held rigidly in the excavation by floor to roof or side to side rams. A cutting head mounted on the boom rotates at very low speed, but with very high torque.

Jan 1, 1987

By Basak Anameric

Pig iron nugget process was developed by Kobe Steel as an environmentally friendlier, economical alternative to traditional blast furnace process. The process aimed to produce highly metallized, slag free pig iron nuggets throughout a single stage heat treatment, utilizing coal as a reducing ? carburizing agent. The objective of this work was to determine whether the pig iron nuggets produced at the laboratory conditions had comparable physical and chemical properties with the blast furnace pig iron. The physical and chemical properties of the pig iron nuggets were determined utilizing x-ray fluorescence spectroscopy, x-ray diffraction, optical microscopy, scanning electron microscopy, energy dispersive spectroscopy and apparent density measurements. The pig iron nuggets had similar chemical composition and apparent density values (6.7 ? 7 g/cm3) with blast furnace pig iron and they had microstructures similar to low carbon white cast iron. These properties make them a competitive alternative to blast furnace pig iron.

Jan 1, 2006

By Frederick C. Rhyner

Drilled shafts have become an economical foundation choice for bridges in the northeast United States, especially when they can be constructed over water without the use of cofferdams. For the Boscawen-Canterbury Bridge over the Merrimack River in New Hampshire, an unusual design was used to avoid the use of cofferdams and avoid the need for pier caps at the waterline. This design used a pair of integral drilled shaft ? columns to form a bent type of substructure for support. Drilled shafts were 8-foot diameter, about 90 feet deep, with 16-foot long rock sockets. These are integrally constructed with 6-foot diameter reinforced concrete columns extending 37 feet from the waterline to the superstructure. Design load cases focused on lateral loads from ice flows, stream flows, wind and seismic events. Alternative analyses using different methods were made to check the design results. This paper discusses the subsurface conditions, design of the drilled shafts and columns, rebar and joint detailing issues, and construction of the drilled shafts.

Jan 1, 2004

General discussion on the above subject, presented at the Pittsburgh meeting, October, 1914. GEORGE S. Rice, Pittsburgh,. Pa.-Undoubtedly there is a serious problem through the juxtaposition of gas and oil wells and coal mines, not only at the present time, but possibly of far more serious import for the future. If one examines a map of the coal fields on which is superposed the oil and gas fields of the country, one finds that they overlap to a very great extent. I may say at the beginning that we have not, so far as I know, had any very large number, of accidents growing out of this situation causing loss of life. Such accidents, or rather incidents, that have occurred have all been rather potential possibilities for disasters due to the leakage of gas from wells into the adjacent coal mines. The condition has been most acute in the Fairmont district of West Virginia, and in the general coal fields southwest of Pittsburgh in Pennsylvania. The accidents which have actually occurred were summarized in Bulletin No. 65 (Oil and Gas Wells through Workable Coal Beds) issued by the U. S. Bureau of Mines, reporting the transactions of several meetings in Pittsburgh, February, 1913, of oil and gas well representives, State geologists, State mine inspectors, coal-mine operators, and representatives of the U. S. Bureau of Mines. This conference was partly brought about through a case in which the Pennsylvania State inspection department had brought suit to restrain a gas company from completing a well through a certain mine. The office of the Attorney General of Pennsylvania asked the opinion of the Bureau of Mines upon the matter; about the same time the Association of State Geologists, at its New Haven meeting, asked the Bureau to take up the problem. Accordingly, it was thought advisable to bring together the several, interests. For the most part the danger is, I think, greater in the future, than at the present time Many parts of the coal fields of Pennsylvania, in Greene County particularly, have been penetrated by numerous wells very close together, and with the present practice of having a large coal pillar around each well, has made or will make the mining of many areas difficult or pro-

Jan 4, 1915

This paper reviews the history of refractory materials, highlights the development of refractory technology over the years, draws attention to the technology behind these materials, and comments on future developments in this field. By walking the path with refractory materials, from their initial uses in BC times, to the composite materials that are used nowadays, and the nanotechnology developments that are currently taking place in this field, the reader will come to agree that refractory materials are indeed very ?cool?! Keywords: refractory materials; bricks; monolithic materials.

Jan 1, 2008

Recovery Process of Carbon Dioxide with Metal Oxides and Metal Hydroxides

Sep 13, 2010

By Yuri L. Nikolaev

The treatment of placer gold with fine gold, associated with gold-bearing sulfide minerals, heavy minerals and oxidized minerals such as manganowolframite (gubnerite) is not an easy task. In this case, this complex material cannot be treated using physical separation methods such as deep concentration and finishing, magnetic separation and solvent extraction. This technology is usually employed in gold washings finishing plant. The easiest way to recover precious metals in the form of an easy-to-sample saleable product is metallurgical treatment. This paper describes the application of pyrometallurgical processes with oxidative roasting, re-cleaning of cinders (if required) and ore-thermal smelting for producing gold bullion. Hydrometallurgical treatment of slags as an additional operation is recommended in order to maximize recovery of valuable metals. After this treatment, a barren leaching cake rich in PGM can be sold in the market. PGM can be collected as gold-silver alloy during smelting which allows the phase formation of polymetallic matte due to specific composition of fluxes. The PGM are then in the form of saleable gold bullions in the refinery.

Sep 1, 2012

By A. C. Veatch

Jan 1, 1921