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A New Technology of Applying SLon-2500 Magnetic Separator to Recover Iron Concentrate from Abandoned Tails

Sep 13, 2010

By John Dean Smith

"In many operations the two most overlooked aspects in the drilling and blasting process is theblast optimization and explosive selection. Often times we find a blast design that seems to work andproduce acceptable results and will use this cut afier cut, even years. When in reality one should never become complacent and should be constantly looking for ways to improve the drilling and blasting operation."

Jan 1, 1995

By John E. Lambert

Automatic control of drum head continuous mining machines was investigated as a means of reducing respirable dust generated and operator variabitity. Literature survey, manufacturer interviews and mine visits were the major information sources. Technically feasible automation concepts were Identified to control sump and shear rates, cutter head elevation limits and sumping distance. These are the elements of a programmed cutting cycle which maintains peak penetrating force on the cutter, to maximize depth of cut and therefore reduce dust generation. Based on the industry surveys, successful underground hardware demonstrations must be completed in order to stimulate the market demand for these advanced control features.

Jan 1, 1979

By E. L. Garton

[Analyses of may crude oils produced in Louisiana are included in reports that t have boon published by the Bureau of Mines. The first report, giving, analyse of 6 Louisiana crude oils, was 3 published in 1921 and this was followed a year later by Report of Investigations 2416,4/ giving 7 additional analyses. The eleven most important of these analyses were incorporated in Bulletin 291.5/ issued in 1928 In 1934 analyses of 26 crude oils produced in southern Louisiana were published.6/ The percent report presents analyses of 72 additional samples of crude oil from 45 fields in 23 parishes In Louisiana.]

Jan 1, 1939

Coals from the Southern Coalfield of New South Wales treated in the Port Kembla coal preparation plants of Australian Iron and Steel Pty. Ltd. differ supstantially in their characteristics. Knpwledge of performance not only enables comparison and promotes better control, but also provides the means for predicting results.Evaluation of performance of cleaning equipment has been made in terms of probable error (Ep). Results for Baum jigs, a Chance cone, heavy medium cyclones, and water washing cyclones were examined. The efficiency factors derived from the probable error were applied to the float and sink analysis, mathematically simulating operating conditions. This method was applied to the Balgownie seam.The Balgownie seam lies between the Bulli and Wongawilli seams in the coal measures of the South Coast and mining on a large scale began recently in the Bulli area. It is known locally as the Four Foot seam and exhibits rather difficult washability characteristics, due to a comparatively high middlings content. These properties and the relatively high inherent ash make careful selection of cleaning equipment essential for optimum recovery. The prediction technique is used to determine the possible results when this coal is cleaned in the Port Kembla plants. Predicted values are compared with results from full scale trial washings demonstrating the validity and accuracy of the technique.Applications of result forecasting are listed.

Jan 1, 1971

By W. D. Monaghan

Flame cutting and welding is one of the major causes of fires and explosions in underground U.S. coal mines. On May 20, 2006, a flame cutting operation at the Darby Mine No. 1 led to an explosion that resulted in five fatalities. On January 22, 2003, another explosion caused by flame cutting at the McElroy Mine resulted in three fatalities and three serious injuries. On June 22, 1999, a flame cutting and welding operation at the Loveridge Mine caused a fire that resulted in sealing of the mine for an extended period. Finally, on March 19, 1992, an explosion at the Blacksville No. 1 Mine that was caused by welding resulted in four fatalities. The National Institute for Occupational Safety and Health (NIOSH) conducted a study on fires and explosions in underground U.S. coal mines that were caused by flame cutting and welding operations to determine the root causes of these types of fires and explosions. The methodology included interviewing mining personnel who perform flame cutting or welding operations in underground U.S. coal mines and visiting mines to observe these operations, and MSHA reports of investigations and accidents statistics were analyzed. The results were used to identify and compare differences between flame cutting and welding practices and techniques in small and large mines, Eastern and Western mines, low seam and high seam mines, room and pillar and longwall mines, and between experienced miners and new miners. As a result of this study, best practices and interventions were developed to reduce the number of fires and explosions caused by flame cutting and welding. This paper provides a summary of this work. Disclaimer: The finding and conclusion in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupation Safety and Health.

Jan 1, 2009

By J. K. Whyatt

Researchers at the U.S. Bureau of Mines collected and analyzed overcore measurements and other indicators of in situ stress characteristics at the Lucky Friday Mine, Mullan, ID. An analysis of these data revealed that significant local variations in in situ stress are present in this mine and that these variations existed prior to mining. High stresses were found to be associated with the most competent strata and a locked section of a fault. An estimate of the predominant stress field was developed for mine-wide modeling. The estimate shows that the greatest principal stress was oriented north of northwest. This information should provide a basis for mine-wide structural modeling of the Lucky Friday Mine and should generate important insights into localized stress conditions, which may significantly affect both local and mine-to-mine variations in seismicity induced by excavation.

Jan 1, 2010

By Thomas D. Kelly

In 1900, the average U.S. citizen’s average life span was 47 years. He traveled about 1,900 km (1,200miles) in a lifetime and resided in a home with an ice-box for food storage and oil or gas for lighting. He communicated by mail, telegraph and crude telephones with limited availability and range. By 2000, the average citizen’s life span was 77 years. He traveled an average of 19,000 km/a (12,000 miles/year) by automobile alone. He resided in a home with many electrical appliances, including refrigerators and electric lights. And he communicated almost instantaneously with any other part of the globe by several widely available means, including portable phones and e-mail.

Jan 1, 2002

By Gray Mullins

This paper presents results from model and full-scale tests to assess the interface bond between a cast-in-place concrete seal slab and steel H-piles in cofferdams. Three different seal slab placement conditions - fresh water, salt water and bentonite slurry - were evaluated and the results compared against controls where no fluid was displaced by the concrete. Normal pile surfaces were investigated. Additionally, the situation of ?soil caked? piles was also tested. In the model tests, eight 15 cm deep, W6 x 15 sections were used for two different embedment depths of 1.5d and 2d, d being the depth of the section. In the full-scale tests, 16 specimens 35 cm deep (W14 x 90 sections) were tested with the embedment varied between 0.5d-2d. The results show that significant bond stresses developed even in the worst placement condition. Recommendations made for revising current values in specifications have already been implemented by the Florida Department of Transportation.

Jan 1, 2013

By O. M. Arafat, J. A. Finch

Since its development, the functional performance equation for ball milling (McIvor, 1988) has facilitated a new understanding of industrial circuit cause and effect relationships, leading to significant strides in operational performance. Success stories of this approach to plant circuit performance improvement are now too numerous to list. Finch and McIvor (circa 1986) also discovered that the functional performance mill grinding rate at the size of interest was the same cumulative grinding rate that is calculated from mill feed and discharge size distributions using a first-order rate equation. By calculating these cumulative grinding rates for all screen sizes, a complete ball mill model is generated (as used by Finch and Ramirez, 1981). Others in industry, Hinde and Kalala (2009), for example, have noted the same. Lacking the complexity needed to maintain their interest, most researchers have ignored this model, broadly opting instead for Epstein’s (1948) characterization of grinding as a chemical reaction, combining selection rate and breakage size distribution functions. The much simpler ball mill model has previously been incorporated into a proprietary circuit modeling program (McIvor, 2005) and used for plant improvement work (for example, see McIvor and Finch, 2007, and McIvor, 2014). Now, by combining this business-friendly ball mill model with optimization criteria from functional performance analysis, a circuit modeling system (including the needed supplementary steps to assure successful plant implementation of circuit design changes) is at the disposal of every plant metallurgist, grinding equipment/ material provider and circuit designer.

Jan 11, 2017

By George W. Maynard

(Pittsburg Meeting, March, 1910.) AT the Pittsburg meeting of the Institute, May, 1879, I made the first announcement in America of the results obtained by Sidney Gilchrist Thomas and Percy C. Gilchrist, ill their efforts to eliminate phosphorus in the manufacture of steel in the Bessemer converter and the open-hearth furnace.1 The first published statement in an American newspaper was a reprint of the first Thomas-Gilchrist paper, 2 which I sent to J. C. Bayles, at that time the editor. At the suggestion of many friends who were present at the Pittsburg meeting, and others who are cognizant of the beginnings of the process in the United States, and for the information of the younger generation of the iron and steel fraternity, I have thought it eminently proper that the history of the process in detail should be given where I made the first announcement and where the process has had its largest development. During my residence in England, from April, 1873, to February, 1879, and as a member of the Iron and Steel Institute since 1874, I was present at many of its meetings during those years. At nearly -every meeting the burden of discussion was the question of the use of pig-iron containing phosphorus in the. manufacture of steel by the Bessemer or the open-hearth process. In my biographical notice of Thomas;3 read at the New York meeting of, the Institute, February, 1885, I show that the working-out of the process was not a hap-hazard or accidental inspiration, but the culmination of many years of investigation of experiments and theories which had been carried on and advanced by chemists and metallurgists at home and abroad. 1 Trans., viii., .5 (1879-80). 2 The Iron Age, vol. 22, No. 17, p. 3 (Oct. 24, 1878). 3 Trans.. xiii., 785 to 791.

Jul 1, 1910

By O. Celep, T. Uslu, Savas

This study investigates the enrichment of a low-grade colemanite concentrate (-3 mm) using a Knelson centrifugal gravity concentrator. Due to its low boron content, the concentrate is unsaleable and has to be stored under appropriate conditions to avoid potential environmental problems. The low-grade colemanite concentrate was comminuted to size fractions of-1 mm, -0.5 mm, and -0.15 mm before treatment in the Knelson Concentrator. The effects of particle size, fluidizing water velocity, and bowl speed on the enrichment process were examined. The B2O3content of the concentrate was increased from 33.96% to a maximum of 45.52%. B2O3recovery increased with increasing bowl speed and particle size, and decreased with increasing fluidizing water velocity. The enrichment process also rejected arsenic and iron to some extent, with a maximum reduction of arsenic from 1360 g/t to 765 g/t and iron from 0.88% to0.33%.

Jan 1, 2015

By R. E. Mclvor

This is an update of an original dissertation on this topic by Lavallee, McIvor and Stolovitch (1992). A step-by-step, technical procedure used to measure and improve the performance of plant grinding circuits was adapted into a training program. ?Systematic Design of Instruction? was applied to: ? Determine if training was a suitable way to deliver this new technology; ? Define the technical content of the program; ? Select program specifications based on learner and context characteristics; ? Design, create and test prototypes of the training modules; and, ? Establish a process for plant implementation. The training program covers numerous skills that are extremely valuable for plant personnel, not only in the grinding area, but also for many other parts of the plant. This paper describes how new skills are brought into the workplace through designed instruction can be an effective alternative to hiring during severe skilled labor shortages.

Jan 1, 2008

By W P. Player

The legislative operating environment, or the mineral regime, that a country has to offer is one of the key determinants that a company wanting to invest in an area takes into account in formulating its investment decision.   The New Zealand Government recognises this and the importance of getting the regime right in order to provide for continuing investment in mineral exploration and mining in New Zealand . In recent years, the Government has given considerable attention to developing legislation which provides for investment to take place; for those making the investments to have a stable, fair and open investment environment with government intervention only when considered absolutely necessary because other approaches are not working; and for the people of New Zealand to know that investment must meet acceptable health and safety standards and have acceptable impact on the environment. Also of key importance is having a clearly defined mining regime which includes rules on how to obtain a permit and rules in respect of ongoing permit compliance, rights to develop a mineral resource and permit conditions (in particular, the royalty regime). In New Zealand , these matters will all be addressed in what are referred to as 'minerals programmes'.   The Crown Minerals Act 1991, which is the legislation governing the allocation and management of permits for Crown owned minerals, requires that the Minister of Energy prepare minerals programmes. Minerals programmes establish the policies, procedures and provisions that the Minister shall follow in exercising his or her functions and powers under the Crown Minerals Act. Minerals programmes set out the principal reasons for and against adopting these policies, procedures and provisions and also restrictions on prospecting, exploration and mining for Crown owned minerals. Essentially minerals programmes define the mining regime for the minerals to which they apply, other than the taxation regime, environmental and health, safety provisions, land access matters and general matters concerning the investment climate.

Jan 1, 1995

By G. Price

The Building Research Establishment installed a base load cell in a driven cast-in-place pile prior to it being tested under vertical load. The monitored base loads were found to be significantly less than could have been predicted by current design methods. The less than expected capacity was attributed to the drilling out procedure. An electro-level system installed in a second similarly formed pile, provided detailed information on the performance of the pile under lateral load. The information obtained was used to check several current design methods for laterally loaded piles. The findings show the potential dangers of attempting to improve design parameters from only limited performance data.

Jan 1, 2010

By Haijian Shi, Drew Pizzo

This article focuses on the appropriate application of subsurface investigation methods for transmission structures, which are typically designed to resist lateral rather than vertical loads. Currently, the three methods used most often for the subsurface investigation of transmission structures in the field are the Standard Penetration Test (SPT), the Cone Penetration Test (CPT), and the Flat Dilatometer Test (DMT). Each of these methods has advantages and disadvantages, and each is more applicable to some scenarios than to others. To gain a better understanding of these test methods and the implications of using them for various kinds of applications, a comparison study was conducted in the field in Maryland, for three boring locations. Each boring location was explored using each of the three tests as stated. The results of the tests and lessons learned are presented and compared, and these comparisons show that the three test methods agree on the majority of the findings. The results from each test method were also used to derive key parameters such as the soil friction angle for given foundation designs considered in order to establish a clear basis for comparison. Recommendations for performing transmission structure subsurface investigations are made in order to optimize the use of each method and thereby optimizing subsequent foundation designs. INTRODUCTION For overhead transmission structures, the most important structural requirement for determining the foundation design differs from the requirement for other structures such as buildings and bridges in accord with the conditions the transmission structures will need to withstand. In addition to the ability to bear a given vertical load consistent with its use, the foundation must bear lateral loads arising from wind and other weather conditions. The foundation types used most often for overhead transmission monopole structures include concrete drilled pier, vibratory caisson, and direct embedment. In order to determine an appropriate and even an optimum foundation design for any given set of conditions, an appropriate subsurface investigation method or approach is needed. Currently, the standard penetration test (SPT), the cone penetration test (CPT), and the flat dilatometer test (DMT) are the three most commonly used subsurface investigation methods.

Jan 1, 2018

Experiment of Improving the Quality and Decreasing the Impurity of Titanium Concentrate in Panzhihua Mine in China

Sep 13, 2010

By S. Banisi, A. R. Hasankhoei, A. R. Ghasemi, E. Razi, G. A. Parsapour

At the pelletizing plant of the Gol-E-Gohar mining and industrial company two parallel dry closed grinding circuits, each with the average throughput of 300 t/h, are used. Each grinding circuit consists of a burner, a dry ball mill (6.2 m×13 m) and an air separator. The ball mill consists of a 2 m-long drying and an 11 m-long grinding chambers. The iron ore concentrate is fed to the drying chamber by a feed chute. The first 1.35 m of the drying chamber consists of 56 flights in two rows to decrease the feed moisture from 5% to below 0.2% and the rest of dryer chamber consists of deflectors to pass the material to the grinding chamber. It was found that when the feed moisture content increased from 1.3% to 3.5%, the throughput decreased by 12% (35 t/h) indicating a low performance of the dryer. Monitoring the wear rate of flights for a period of 12 months showed that the first 0.8 m length of the flights length did not experience any wear. This means that about 59% of flights do not contribute in material distribution and drying. A DEM simulation of feed chute and the drying chamber demonstrated that due to the inappropriate design of feed chute most of materials do not get in touch with the first 0.8 m length of the drying chamber. To overcome this problem, various feed chute designs with different geometries were simulated by the KMPCDEM© software. With the aim of arriving at a proper material trajectory, where the total length of the flights are used, a new feed chute was selected. The simulation results indicated that if the height of the flights is increased from 1.60 to 2.26 m and the slope is increased from 45 to 48 degrees the material arrive at the first 0.48 m of drying chamber. In this manner, the unused part of the drying chamber decreases from 59% to 36% of the length. After installation of the new feed chute, during a period of three months the throughput increased by 36 t/h.

Jan 1, 2018

By Don W. Lake

Of all the blast monitor& instrumentation systems and techniques av&able today, highspeed photography and videography remain as the most valuable, stand alone, diagnostic techniques to evaluate full scale blasts in the mining and explosives industries. Highspeed image data, coupled with information from other instrumentation systems, such as continuous VOD records, seismographs, laser surveying systems, refraction seismographs, etc. can eIiminate many assumptions about what actually took place in a blast. Thus, diagnostic confidence in evaluating both good and bad blasts is increased, and optimum blast designs are achieved considerably faster when compared to the trial and error approach or relying on just the experience factor.

Jan 1, 1992

By J-M Huizenga, Q Shu, Y Lai, J Hammerli

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Baiyinnuo’er Zn-Pb deposit is a typical skarn deposit in NE China. Skarn and orebodies mainly occur between different units of the Lower Permian Huanggangliang Formation carbonates-sandstone-mudstone or within the contact between intrusions and marble. Skarn minerals are dominated by prograde garnet and clinopyroxene, and the main ore minerals are sphalerite and galena. We conducted single fluid inclusion compositional studies using laser ablation inductively coupled plasma mass spectrometry on clinopyroxene (pre-ore-stage mineral) and sphalerite and calcite (syn-ore-stage minerals). The results show that the Baiyinnuo’er fluids are distinctly different from basinal brine but similar to magmatic fluid, thereby indicating that the deposit has a dominantly magmatic origin. This interpretation has also been supported by the Cl/Br mole ratios, which remain stable (~500) in different fluid stages. The decreases for most of the elements in the fluid inclusions from pre-ore-stage clinopyroxene to syn-ore-stage sphalerite and calcite suggest that mixing with groundwater has occurred during mineralisation, with significant Zn, Pb and Ag deposition.CITATION:Shu, Q, Hammerli, J, Chang, Z, Lai, Y and Huizenga, J-M, 2015. Laser ablation inductively coupled plasma mass spectrometry study on fluid inclusions of the Baiyinnuo’er skarn Zn-Pb deposit, north-east China, in Proceedings PACRIM 2015 Congress, pp 451–456 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015