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By E. D. Hummer

During the planning of the fine coal cleaning addition at the Gary, W. Va., Coal Preparation Plant of United States Steel Corp. careful consideration was directed toward the problem of minus 48 mesh refuse disposal. The plant flow sheet included wet screening the raw coal at ¼ in., pumping the minus ¼ in. raw coal to bowl desiltors for desliming, and then cleaning the deslimed raw coal on tables. The material to be removed from the circuit as minus 48 mesh refuse consisted of the minus 100 mesh desiltor overflow thickened in two 120 ft diam thickeners and minus 1 mm screened from the table refuse. Later a flotation plant was added to recover coal from the desiltor overflow, and a classifier replaced the screens to make a sharper size separation of the table refuse at 48 mesh. Today the minus 48 mesh refuse at Gary consists of thickened flotation tailing and thickened spiral classifier overflow. The transportation of large quantities of fine, wet refuse filter cake mixed with jig and table refuse over existing conveying equipment would have been neither dependable nor economical. Filtration was therefore impractical, and disposal of the fine materials was a problem. The decision was to pump the material to storage ponds.

Jan 3, 1965

By Akhila Manne, Prasad P. V S R

Storage tanks are heavily loaded thin-shelled structures that exert large loads on and require large foundations to support them. They are generally very sensitive to foundation settlements as it may hinder the performance of tanks resulting in significant commercial or social impacts. Selection of their foundation is dependent on availability of suitable ground and limitations imposed by design specifications. Design of the tank foundations is generally based on theoretical methods and validation by representative field tests. This paper reviews settlement criteria for storage tanks as per national and international standards, case studies of large to medium diameter tanks supported on deep foundation i.e., bored cast-in-situ piles and shallow foundations on improved ground and their performance during load tests & hydro-tests is discussed. Paper concludes that storage tanks can also be supported on shallow foundations resting on improved ground reducing the settlement, time and cost significantly depending on the sub-soil.

Nov 1, 2022

By James Mackie

The Vancouver Stock Exchange (VSE) has been providing venture capital for start-up companies since 1907. Ninety years' experience in the junior mining industry has enabled the VSE to develop policies and procedures tailored to the unique needs of start-up companies. Policies and procedures applicable to listed companies are documented in the Corporate Finance Services Department "Policy and Procedures Manual." Approximately 50% of the companies listed on the VSE are in the mineral exploration and development business. The largest number are exploring base metal, precious metal or diamond properties. A recent count shows that about 20 companies are exploring industrial mineral or non-metallic deposits. The minerals sought by these companies include limestone, decorative stone, building stone, lava rock, wollastonite, zeolite, garnet and graphite. There are two basic routes to obtaining VSE financing for an industrial mineral property. The owner can either sell an interest in the property to a listed company or form a company and have it listed on the VSE. In each instance, the listed company is responsible for raising funds to develop the property. A typical financing consists of the sale of company securities byway ofeitherprivate placement or prospectus offering.

Jan 1, 2001

By T. M. Barczak, Zach Agioutantis

The Support Technology Optimization Program (STOP) has been developed by the National Institute of Occupational Safety and Health (NIOSH) to provide a comprehensive tool for evaluating the performance of available secondary roof support systems and designs based on support strength, convergence, cost, installation time and material handling considerations. This program uses engineering models developed from full-scale testing of numerous supports under controlled loading conditions in the unique NIOSH Mine Roof Simulator load frame to determine the support load-displacement performance as a function of the various sup- port design parameters. Both standing supports, such as wood cribs installed within the entry, and intrinsic supports such as cable bolts, can be evaluated. Support systems can be designed and compared for use in a new mining section or to evaluate potential replacements for an existing design. The support design requirements are defined from 1) estimating the failure height in the immediate roof, 2) in-mine measure- ments of support and strata interaction or development of ground reaction curves from numerical modeling, 3) the performance of an existing support system, or 4) from any arbitrary load and convergence criteria. All settings can be saved to permit resuming an evaluation in progress at a later time. This paper presents the updated MS Windows version of this tool, which can be easily installed and run on a personal computer. This Windows implementation will feature a project and application scenario setup where multiple scenarios can be assigned to one project. Scenarios can then be compared on support parameters and cost. Cost parameters can be provided either as individual cost items or using a price grouping feature. Additional support performance curves and/or additional ground reaction curves will be distributed with program updates as new information is developed. Users can also provide their own support and/or ground reaction curves.

Jun 25, 2024

By G. A. Moruzi

Two sulphide dust secondacy explosions have occurred in the mines of the SUdbury operations of Falconbridge Ltd. during the past 18 months. 'Ihe main similarity between the occurrences is that they both happened in vertical crater retreat blasthole stopes. A relatively high p:,v.tier factor was noted in both instances. other details are enumerated and examined, as well as some results of tests done by Noranda Research on company ore samples.

May 11, 1988

By F. Bornman

Ore quality is declining, and the current spirals in mineral sands extraction is deemed inadequate to efficiently extract the valuable minerals. A new spiral was developed, the 117HM with the aim to extract the total heavy minerals in the order of 4.0% - 6.0% and the economic heavy minerals in the range 1.0% - 2.2% from the feed. An important measurable in the gravity concentration of mineral sands is recovery. Recovery measures how effectively the separator has extracted the valuable mineral contained in the input stream. The number of turns on the spiral trough influences the residence time of the feed slurry. A further optimisation followed with the development of the twelve-turn 117HM spiral. Four more turns were added for better recovery. The paper quantifies the effect of residence time on recovery.

Mar 30, 2026

By Yuzhe Zhang, Xiaodi Huang, Xinli Wang, Bowen Li, Matthew Andriese, Xin Yan, Jiann-Yang Hwang, Zhiwei Peng

Using a TM0n0 cavity system as the main reactor, an integrated process was developed to find the best condition for waste tire rubber to absorb microwaves. The penetration depth was the main character for determining the best condition. The penetration depth is defined as the distance from the surface into the materials at which the traveling wave power drops to from its value at the surface. The waste tire powder was irradiated by two different microwave frequencies, including 915 and 2466 MHz. The study was conducted with same powder size and atmospheric condition. The effects of temperature and microwave frequency were analyzed based on the experimental data. The main trends are higher the temperature, the absorption will be better and the higher the frequency, the better the absorption will be.

Mar 1, 2017

By S. N. Monteiro, J. Alexandre, L. G. Pedroti, D. P. Santos, B. C. Mendes, A. R. G. Azevedo, G. C. Xavier

The glass cutting industry is responsible for generating large quantities of waste, during the stages of cutting and polishing. The disposal of this material generates a cost to the company, thus looking for ways to repackage it, so there is the possibility of incorporating it into the adhesive mortar. The objective of this work is the characterization of waste and assessment of the properties of these mortars, fresh, and check the possibility of their use. As for the characterization, were carried out particle size testing, density and pozzolanic activity, for the fresh state were performed tests of air content, water retention consistency and entrained particular index. Were incorporated 0,10, 15 and 20% of the amount of sand. The results showed that the material on display ha spotential for use in adhesive mortar, with values within the limits stipulated by Brazilian standards.

Mar 1, 2017

By Jinsheng Wang, Zhixiong You, Xuewei Lv, Yu Zhang, Jie Dang

Electro-titania slag is generally used as the raw material for titanium dioxide production by sulfate process. The phase composition of titanium as well as their disseminated grain size have significant effect on the acidolysis of titanium. Anosovite is considered as the most favorable Ti-bearing phase due to its high acidolysis ef ficiency, while silicates and rutile are not soluble in concentrated sulfuric acid. Different cooling rates will play a significant effect on the phase structure and particle size, which directly affects the acidolysis ratio of titania slag. In this paper, the influence on acidolysis ratio of titania slag at different cooling rates was studied. The results revealed that slower cooling rate resulted in the formation of larger particle size and a comparatively higher acidolysis ratio was obtained. On the contrast, rapid cooling was disadvantageous to the leaching of titanium as the smaller particle size anosovite was wrapped by glass phases.

Mar 1, 2018

By Bowen Li, Canhua Li, Mingsheng He

Steelmaking slag is a by-product in considerable volume and a valuable material for various applications. In general, steelmaking slag is an alkaline compound of CaO, Fe2O3, and SiO2. However, its characteristics varies depending on the feedstocks, steelmaking process and cooling method of the slag. To utilize this by-product effectively, this study investigated the characteristics of steelmaking slags taken from Wuhan Iron & Steel Co. Ltd. The results showed that the slags mainly consist of the oxides of calcium, iron, and silicon, with low contents of magnesia, alumina, and manganese oxide with a feature of high alkalinity and lime saturation factor. The major mineral phases include belite, calcium ferrite, calcium hydroxide, wustite, quartz, and small amount of elite. Thermogravimetric analysis indicated the weight loss from ambient temperature to 800 °C is 8% in total. Melting test showed the glass transition temperature is between 1300 and 1350 °C, flow temperature is about 1400 °C. The slag samples investigated in this study can be considered as a typical glass-ceramic composite.

Mar 1, 2018

By Zhenzhou Yang, Zuotai Zhang

In the present study, we proposed a method that using sewage sludge (SS) as alternative fuel and raw material to produce cement clinker. It was found that the increasing amount of SS can favor for the formation of tricalcium silicate (C3S) but the excessive amount can cause the impediment effect. Furthermore, SS contains high contents of trace elements, especially for zinc and manganese. The thermodynamic equilibrium calculation of Zn and Mn are also conducted to further understand their transformation behaviors and the results show that zine is predicted as a volatile element while manganese shows great condensed potential during the cement clinker calcination process.

Mar 1, 2017

By W. S. Hui, M. G. Silva-Valenzuela, H. Wiebeck, F. R. Valenzuela-Diaz, B. B. Michel

Biodegradable polymer microcapsules have been used as a control sustained release system with many applications. Studies reveal that the incorporation of nanoparticles improves matrix properties, even more so if the clay is modified. The objective of this work was to compare microcapsules of poly (succinate-co-butylenelactate) (PBSL) reinforced with Brazilian clay, composed of smectites and kaolinite, in its natural (MMT/K) and modified (O-MMT/K) forms. Nanocomposites and microcapsules were synthesized by emulsification-diffusion of solvent and solvent diffusion methods. Its characterization was then performed by scanning electron microscopy (SEM), stereo microscopy and wide-angle X-ray diffraction (XRD). The results reported corroborate that PBSL/OMMT-K form an intercalated montmorillonite and kaolinite nanostructure, capable of generating uniform spherical microcapsules with diameter values smaller than that of PBSL/MMT-K, reaching 5–10 lm. DRX indicates that there was a real change in the clay structure. The incorporation of modified clay showed an improvement in surface quality and the strength of microcapsules, making it possible to produce smaller sizes.

Mar 1, 2018

By Joe Atalla, Leojenen Etulle, Jesse Desrochers, Joseph Mukendi Kabuya, Remi Proulx, Ruilin Yang

The Mont-Wright mine is Canada's largest open-pit iron ore mine with multiple open pits in operation. It is operated by ArcelorMittal Mining Canada in the northeast of the province of Quebec, near the town of Fermont. Fragmentation of rocks with explosives generates vibrations and gas expansion that damage intact rocks, affect existing crack networks, reduce the shear strength of discontinuities and the quality of the rock mass of the highwalls. The efficiency of its blasting operations is challenged by the need to optimize production and manage the risk of mine slope instability caused by vibrations from successive blasts. This paper presents a Multiple Seed Waveform (MSW) vibration model that was established at the mine for this purpose. Near-field signature hole blast vibration monitoring was conducted in multiple areas to establish site characterization as input to the blast vibration modeling at the highwalls of the site. The vibration attenuation laws were established and the effects of different blasthole diameters, shifting frequencies and presplit design were evaluated. Based on the results obtained from the near-field blast vibration monitoring, the calibrated MSW vibration model was used to select blast design parameters to control blast vibration while maximizing productivity of blasts at Mont-Wright mine.

Jan 26, 2026

By Onuralp Yucel, Osman Halil Celik, Hakan Morcali

In this study, some experiments were performed for the dimensional control, pre-treatment, getting salt, metallic aluminum and aluminum oxide into the solution of 15 kg aluminum black dross obtained from a private company which recycles aluminium drosses. Water leaching experiments are done for removing salts and aluminum nitride. Temperature stirring speed, solid-liquid rate are investigated while water leaching experiments. Removing of AlN is provided at 25 °C at a rate of 42.48%, at 80 °C at a rate of 86.4%. Leaching experiments performed with NaOH. NaOH concentration and time was analyzed. Efficiency of including metallic aluminum into the solution is determined to be 98% approximately. Melting (fusion) experiments were performed with NaOH at high temperatures to include aluminum oxide in the structure of the remaining after dissolving process into the solution and after dissolving the resulting structures in water, efficiency of including aluminum into the solution is determined to be 85%.

Mar 1, 2018

By M. Zaske, E. R. Mortensen

"As mine operators continuously look for ways to improve functionality and increase capacity of their facilities, existing process equipment is often pushed to and past its designed limitations. As a result, equipment manufacturers are asked for economical solutions to meet redefined processing needs. Newmont USA (Newmont) in Nevada was faced with such a need in their Carbon-in-Leach (CIL) train. In a collaborative effort between Newmont and Derrick Corporation, tests were conceived to assess the viability of drop in replacement screen using a three dimensional screen panel. The urethane pyramid screen panel was designed to increase flux while maintaining the existing equipment footprint. The test is the end result of an ongoing research and development project that Derrick undertook in an effort to refine and upgrade their urethane screening media. The application of this new screening media is presented for this CIL application along with future plans to implement the technology in trash, safety, carbon dewatering, carbon sizing, and other scalping applications.INTRODUCTION In Spring of 2014, Process Machinery Associates (PMA), Derrick Corporation’s (Derrick) local area representative, met with Newmont USA (Newmont) to discuss the operation of the in tank screens in the carbon in leach (CIL) train at Twin Creeks, near Golconda, Nevada. The process was originally designed for 13,000 +tons per day (tpd) but has been steadily rising since the plant was commissioned and now Newmont requires 16,000 tpd to be processed. The original screens were running at their maximum capacity and Newmont required additional screening capacity to continue the upward trend in production. Physical separation by use of screening is one of mineral processing oldest methods. Screening media can be prone to blinding and pegging and the necessary support structures required for finer apertures result in smaller open areas. Therefore, more screening area generally requires larger panels and therefore larger machines, screening media that doesn’t blind, or a combination of both. In an effort to avoid larger machines, Derrick Corporation had been working on a revolutionary three dimensional panel which would add non blinding screen area in the same footprint of an existing machine. Alpha testing of the new screen panels began at Newmont Mill 2/5 (Carlin, Nevada) in July of 2013 and was still occurring when PMA approached Twin Creeks about beta testing a refined machine and pyramid panel. After presenting the initial results, Twin Creeks determined that an upgraded machine and pyramid panels would be a possible solution to meet production needs. The testing of a machine eliminated the risk of capital costs to Newmont and provided Derrick the opportunity to obtain additional data."

Jan 1, 2015

By Michael Klichowicz, Holger Lieberwirth

"For a detailed prognosis of mineral comminution processes, simulation tools like DEM still pose various challenges. Less realistic mineral structures can affect the results of simulation models such as bonded-particle models (BPM). Hence, in order to design mineral processes with these models as tools, representative mineral input data should be used. The article shows, how realistic 2D-structures can be modelled by taking advantage of the parameters identified by the Quantitative Mineralogical Analysis (QMA). Important quantitative parameters can be derived by analyzing three orthogonal thin or polished sections. For this reason point, line, and area analysis are applied. The mentioned parameters precisely describe the texture and structure of minerals. The newly developed software is able for the first time to semi-automatically analyze images of mineral structures using QMA. Moreover, statistically equivalent structures of minerals can be modelled using the QMA- parameters. Generating synthetic, but equivalent mineral structures opens the door for more reliable BPM based simulations. Within future research, the procedure will be adopted to generate 3D-structures. Therefore, QMA-based routines that already have been applied to generate 2D-models shall be utilized as basis. The aim of this procedure is to synthesize realistic microstructures based on certain statistical figures in order to improve comminution simulations.INTRODUCTION Due to its increasing capability, the use of computer technology is permanently intensifying in the design of mineral processes. The recent past has impressively shown that computer models can enhance the understanding of mineral processing. There is in fact a rising number of research activities, which are using simulation approaches to study various aspects of it. Weerasekara et al. (2013) give a comprehensive overview over the application of discrete element modelling (DEM) in the science of comminution.Nonetheless, using simulation tools such as DEM in general still poses a challenge. For a detailed simulation of a mineral comminution process with DEM, bonded particle models (BPM) appeared suitable in the past. The following issues, however, affect an appropriate prediction when modelling with BPM:• Simulations with high numbers of particles may need a lot of time for computation. • Internal modeling parameters like the spring and damper constants in DEM have to be adjusted by comparing its specific crushing behavior in the simulation to reality.• In order to use DEM for prediction of mineral processing, it is essential to validate the correctness of the models and assumptions, which is sometimes difficult. As Weerasekara et al. (2013) have stated it is crucial that the DEM method as well as the DEM code work properly.• It is challenging to implement the complex geometric structures of real minerals into the model."

Jan 1, 2016

By G. Wang, L. R. Moore, Y. Xiong, J. Gu

"Quartz is the second most abundant mineral in the earth’s crust. Not only does quartz have many valuable industrial applications, it is also one of the most concentrated gangue minerals encountered in the processing of other minerals. Minerals such as hematite, apatite, calcite, feldspar, barite, and many more. Numerous applications of industrial minerals are sensitive to the hardness and abrasiveness encountered with quartz minerals, while other applications may lead to processing challenges for the end user. Therefore, process and chemistry optimization must be applied to ensure optimal grade is obtained for these valued industrial minerals. Extensive studies have been conducted in processing various industrial minerals, thus achieving a range of quality specifications, which entailed the application of ArrMaz’s CustoFloat and CustAmine collectors towards the separation of quartz from other minerals. INTRODUCTION Industrial minerals often have the misfortune of the gangue mineral being very similar in surface charge, and coordination properties, to that of the mineral of interest. An example is seen in phosphate beneficiation, when dolomite can be a gangue minerals (Table 1). Therefore, the development of processing reagents are quite complicated. Some minerals, like clays, may be washed away. However, most require the manipulation of the pH, in efforts to fine tune the system to the narrow difference in isoelectric points of the different minerals, as well as the knowledge, and resources that are necessary to exploit the differences to yield and an optimal grade/recovery. In some cases, the application of a depressant may be required, such as the phosphoric acid commonly applied to achieve the optimal balance of grade/recovery for phosphate from a mineral with elevated concentrations of dolomite (Wang, 2016), or the application of hydrofluoric acid to assist in producing feldspar product from a mineral rich in quartz (Heyes, 2012).ArrMaz's CustoFloat and CustAmine product lines have successfully been applied to the processing of industrial minerals for more than 50 years. Applications include, but not limited to phosphate, sand (glass, foundry & high purity quartz), clays (feldspar, kaolin, etc.), and many carbonaceous and sulfate minerals. The successes of these 50 years are largely due to ArrMaz's ability to tailor make the processing chemistries to fit the ever changing and declining mineral feed grade and variations in water quality (Moore, 2015; Moore, 2016). This technical knowledge of mineral processing is strongly complimented by the intimate service programs in place at many of the beneficiation plants."

Jan 1, 2018

By Gergely Markos

Uranium mill tailings represent a potential threat to the human habitat by containing large amounts of radioactive and chemically toxic substances in high concentrations. These: undesired components enter the human habitat in various pathways such as by erosion and water or air transport. The main objective of this investigation was to evaluate the actual movement and model the potential movement of contaminants by seepage of water from the tailings into the subtailings soil. This report represents various models of the movement of contaminants using both theoretical approaches and empirical evaluation of data available from other investigations. The data consist of field measurements and laboratory determi¬nations of major and trace cations, the dominant anions, pH, and Eh of moist solids, extracts, and waters from the tailings and surroundings. Evaluation and interpre¬tation of data were accomplished by using Eh-pH diagrams, various statistical methods and the WATEQFC computer program. Data analyses show that the critical area of investigating movement- is the interfaces between tailings and the external environment. The chemical differences at interfaces seem to result in a sink system for contaminants. The tailings-soil¬-water system shows extreme complexities because of chemical and physical hetero¬geneity of the system preventing the use of a single comprehensive model to represent real conditions. The validity of the simplifying assumption used has been shown and increasing complexity has been built into the models. Analogs of these models can be used for evaluation of similar systems.

Jan 1, 1981

The mineral Industry, following the economy as a whole, experienced little growth in 1992. However, with modernized plants, efficient workforces, and lower operating costs, the industry is well positioned to take advantage of possible improvement in the national economy during 1993. In addition to the significant 1992 events highlighted below, important events, trends, and issues within individual mineral industries are addressed in the commodity sections that follow. The value of processed materials of mineral origin is estimated to have been about $310 billion in 1992. The value of U.S. raw nonfuel minerals production in 1992 is estimated at approximately $32 billion, a 3% increase over 1991. The value of domestic minerals production has increased in all but 4 of the last 32 years.

Jan 1, 1993

By P. Hatefi, O. Rahmani, M. Noor-Mohammadi, A. Tohry

"Depressants play an important role in the selective separation of impurities from iron minerals by direct or inverse flotation. In this paper, sodium co-silicate (SCS) with chemical formula of Na4SiCO6, as a depressant with pH modifier features, has been synthesized and used for phosphorus bearing iron ore in anionic reverse flotation. In this process, phosphorus is floated while the iron oxides are depressed, using fatty acids as collector in an alkaline medium. Batch and pilot flotation tests were carried out to investigate the influence of SCS on the separation selectivity of phosphorus from iron oxides. Also the depression mechanism of SCS on hematite surface was investigated by microflotation tests and FTIR spectroscopy measurements. The flotation results indicated that without using a pH modifier, the pH of pulp could reach up to 10, when SCS was used as depressant. In this condition, a better depression performance was observed compared to sodium silicate (SS). Using the SCS, phosphorus and total iron content in iron concentrate was 0.046% and 66.29%, respectively, compared to SS where these values were 0.06% and 65.75%, respectively. As a result the weight recovery of iron concentrate was increase by around 4%, compare to SS. It was also found that 238 g/t of SCS could be used instead of 3 types of reagents collectively, including 32 g/t of NaOH, 151 g/t of Na2CO3 and 400 g/t of SS gel.INTRODUCTIONThe phosphorous presents in iron ore minerals is mainly in the form apatite mineral. The apatite is separated from iron ore minerals by magnetic and flotation methods (Ma, 2012). The reverse anionic flotation of iron is one of the most common method for removing phosphorus from iron concentrate (Araujo et al., 2005).Usually apatite minerals are readily floated using anionic collectors such as fatty acids (Ma, 2012). In this conditions the iron minerals are depressed and by modifying the pH in alkaline conditions, selective separation of phosphorus from iron concentrate can be achieved. Depressants including; sodium silicate (SS), starch, dextrin, guar gum and humic acids play an important role in the reverse flotation of iron ore (Kar et al., 2013; Ma, 2012; Turrer and Peres, 2010; Araujo et al., 2005). Studies have shown that SS has a better effect on iron recovery and phosphorous reduction, compared with other depressants (Tohry and Dehghani, 2016; Qi et al., 1992, Dho and Iwasaki, 1990). In most flotation processes, modifiers are used to adjust the pH. To achieve alkaline conditions, mainly pH modifiers such as carbon dioxide and sodium carbonate are used."

Jan 1, 2018