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By J. Finch, J. Yianatos, N. W. Johnson, R. Espinosa-Gomez

A method of determining the maximum concentrate solids rate or carrying capacity is described for given column operating conditions. The method requires alteration of the feed rate of solids to the column at a fixed residence time by manipulation of the % solid of the column feed pulp or the bias rate. The carrying capacity was measured for five streams at the Mt. Isa Mines Pb/Zn and Cu concentrators. As a potential scale up parameter, the mass of solids per unit time per unit column cross section (Ca, g/min.cm2) is explored. Ca is tentatively related linearly to the 80% passing size (d80) of the concentrate. For d80 < 15 pm Ca was less than 4 g/min.cm2 (8 lb/min.ft2) which makes it a critical consideration in scale-up for such fine feeds. An alternative carrying capacity parameter, mass of solids per unit volume of gas Cg was not as useful as Ca since Cg varied inversely with gas rate.

Jan 1, 1988

By Malcolm Heyburn

Airborne and ground magnetic surveys were made over and in the vicinity of the Sanford Hill ore body at Tahawus, Essex County, New York. These geophysical surveys served to: l. delineate, lithologic and structural features associated with the ore bodies; 2. indicate a major extension of the Sanford Hill ore body; and 3. guide a drilling program to prove this extension. The titaniferous magnetite ore body at Sanford Hill is associated with gabbro occurring in anorthosite. The contrast in the magnetic susceptibilities of these rock types, reflected in the magnetic measurements, allows geologic-mapping showing rock types and inferred structural features. The anomalous magnetic high of the airborne magnetometer survey indicated a southern extension of the Sanford Hill ore body. Diamond drilling, guided by the airborne and specifically the ground magnetic results, substantiated this interpreted ore extension to be of major magnitude.

Jan 1, 1961

By Felicia F. Peng

The naturally occurring aged manganese oxide coated on the granular media was found to have a catalytic effect on the removal of low concentration of Mn(II) (-1 ppm) from drinking water. Applying this principle, a manganese removal technique was developed for removal of higher concentration of Mn(II) (-100 ppm) from mine drainage by using various aged filter media and synthesized granular media with manganese oxide coatings. Laboratory-scale continuous granular media column experiments were conducted to assess the feasibility of manganese oxide-coated granular media for Mn(II) removal from synthesized mine drainage. The removals of Mn(II) were evaluated as a function of operation parameters including solution pH, manganese oxide concentration coated on the media, interstitial velocity, and oxidant concentration of influent. Higher solution pH and/or higher manganese oxide concentration promoted the removal of Mn(II) on the oxide-coated granular media under low interstitial velocity. Addition of sodium hypochlorite as an oxidant in the influent resulted in continuously regenerated oxidized surface to serve as the catalyst for Mn(II) oxidation reaction on the surface of oxide-coated media.

Jan 1, 1994

By P. Mousset-Jones, F. Calizaya

Ultrasonic anemometry is a relatively new method of measuring the air velocity in underground excavations and is not widely used. The method has been mainly used for surface applications, such as meteorology and fluid flow measurement. Several instruments were looked at to determine their applicability for continuous underground monitoring systems. The units fall into two main categories: variable distance units and fined distance units. The method relies on the acceleration and deceleration of ultrasonic pulses transmitted through a moving airstream. This study presents some of the results of the testing of variable and fixed distance ultrasonic anemometers in a wind tunnel and a mine drift.

Jan 1, 1995

By J. O. Costello

Marble is a preferred surfacing material in up-scale buildings. Its use increased in the 1870&apos;s with rising national wealth and declined in the 1950&apos;s when synthetic materials for these applications were developed. Natural marble is now limited to high-end domestic and commercial structures. Cultured marble is a paste of white marble dust and polyester resin cured in molds yielding fixtures of specific finished dimensions. Dyes incorporated at different stages in the mixing cycle mimic shades and veining of natural marble. This paper discusses the filler requirements for cultured marble production and reviews new techniques to cut and finish natural marble.

Jan 1, 1999

By Thomas J. Neil, O&apos

Mine land reclamation is a comparatively new science-Although some mining companies point with pride to reclamation efforts of 20 to 30 years ago these were the exception rather than the rule. In the last ten years the skyrocket of environmental awareness has been awesome to behold. Future shock gripped mine operators everywhere as they struggled to cope with rapidly changing and escalating demands. The initial result was that two divergent points of view became dominant. Environmentalists said, "Put it back the way it was," and the miners responded, "Let&apos;s grow some weeds and hide it." These views are not surprising as they represent rather obvious alternative responses, albeit at opposite ends of the decision spectrum. The former case has prevailed more often than the latter, as most state and federal legislation -- both proposed and passed -- has required drastic alteration of the post-mining landscape so that evidence of prior mining is largely obliterated. An exception to this has been in porphyry copper country where the infrequent abandonment of mines has given emphasis to the second philosophy -establishing vegetative cover on mine waste materials. Now, it should come as no revelation to most mining people that both of these approaches to mine reclamation suffer from serious drawbacks when applied to open pit copper mines. First, whereas waste dumps and tailings dams can be vegetated with some aesthetic benefit, the massive presence of copper mining operations remains very prominent. It is difficult to conceal an open pit copper mine. Second, returning open pit copper mines lands to their original topography and productivity is simply not a reasonable alternative.

Jan 1, 1976

By M. L. Sharrah

Communication about the energy problem has come at us in great profusion during the last couple of years--reports, speeches, editorials, advertisements--and events. Events such as the Arab embargo on oil exports which vividly demonstrated the world&apos;s dependence on oil, a finite and nonrenewable resource. And the three-fold increase in the price of oil which provides a constant reminder of the political and economic implications of dependence on foreign oil. A distinction among countries exists today which was almost inconsequential two years ago--the oil exporting nations and the oil consuming nations. The only rational way for the consuming countries to lessen the political and economic clout of the OPEC group is to reduce their dependence on oil. The United States is capable of playing a significant part in such a move for several reasons.

Jan 1, 1975

By Alan English

This paper reviews the process control systems used in early commercial pelletizing plants, traces the development of these systems into present day practice, and briefly outlines advanced automation concepts being considered for future installations. It deals specifically with controls for the balling circuit, pelletizing machines, and related material handling and combustion equipment. The importance of instruments for visual observation and data logging is discussed, and the potential use of computer control is evaluated.

Jan 1, 1965

By Alissa Lockett, Chris D. Breeds

Central Water Integration Project (CWIP) Segment 5-1 is the most critical segment of a regional water supply project that transfers groundwater from Burleson County to northern San Antonio, replacing over 20% of that City’s water supply with a new source. CWIP Segment 5-1 included three tunnel reaches totaling 10,350-ft and 5 shafts that were constructed inside the City in an area known to contain large karst features. This paper describes site work used to investigate the alignment for karst features, manage potential environmental impacts, develop the contract package required for mitigation and the means and methods used to mitigate the large karst features that were encountered.

Dec 1, 2022

By M. G. Karfakis

Grouting has been used in underground mining for more than twenty years. Chemical grouting is often used as a remedial measure when the implemented ground control program is unable to completely prevent structural failures or when there is a need for preventing a structural member from unraveling. Utilization of the polyurethane grout currently being used is restricted by its limited range of physical and mechanical properties that restrict its utilization. To overcome some of the drawbacks of polyurethane, research has been conducted on a newly developed polyester based grout. The polyester resin, identified by Sandvik as StrataGrip, provides a number of features, including variable gel times and much reduced chemical hazard. Equally important are the mechanical properties of the product. The strength and deformability of any chemical grout must be compatible with the intended purpose of grouting and the expected deformation of the rock that is to be grouted. Assessment of the mechanical properties of polyester grout is the focus of this work. Field experiences and laboratory research have defined the properties of an effective grouting material. Experimental results indicate that the polyester grout meets or exceeds the recommended properties for many injection applications. Furthermore, the results suggest that the ability to adjust mechanical properties via resin formulation has the potential to expand the applicability of chemical grouting in ground control.

Jan 1, 1997

By L. Frost

The establishment of a retreat system of longwall mining in this submarine coal field has been under study for many years and, although in special cases there have been limited local applications of this method of mining, there has been no attempt until quite recently to establish a uniform system of longwall retreating&apos; in this area (see Figure 1) Where retreat walls were established, it was strictly as a result of physical, rather than economic conditions. In some of the operations- of the Corporation, where the coal was liable to spontaneous combustion- or the area subject to bumps as in No. 2 Mine of the Cumberland Railway and Coal Company in Springhills the recovery of the coal on a retreat system was more or less a necessity.

Jan 1, 1964

A linear programming model with integer sequencing variables is developed to schedule limestone production for a quarry in Central Japan. The model is used to optimize raw material production from the quarry supplying limestone to cement, quick lime and aggregate plants. Typically, the mining in the quarry takes place in four to six different areas each area having 3 or 4 mining increments. Each mining increment contains different quality of limestone. The limestone production from the quarry is transported to the plants byway of 3 ore passes. Each plant requires a given quantity of limestone per period meeting certain quality constraints. This paper will describe development of the scheduling optimization model and how it is used to schedule production by period within the quarry to meet the capacity and blending requirements of the plants.

Jan 1, 2003

By J. H. Desautels

The modern coal mining industry is subject to a vast array of regulations affecting virtually all aspects of its operations. Probably the most significant over-sight role involves the Office of Surface Mining Reclamation and Enforcement (OSH) established by the Surface Mining Control and Reclamation Act, or SHCRA.1 Although complying and coping with SHCRA can be difficult for coal operators, this complex regulatory process has helped insulate the industry from ongoing efforts to extend regulation under the Resource Conservation and Recovery Act, or RCRA, 2 to aspects of the mining industry in general. The Environ-mental Protection Agency (EPA) has struggled with regulation of mining wastes under RCRA since the mid-1970&apos;s, but RCRA itself places most coal mining wastes firmly under the control of OSH and SHCRA. Despite the general exemption from RCRA regulation for waste materials that result from extraction and processing of coal itself, there may be circumstances under which coal mining operators could find themselves subject to regulation under RCRA or a number of other statutes administered by EPA. This paper will review briefly the history of mine waste regulation under RCRA, as well as touch on the policy decisions that led to the exemptions from RCRA regulation. The paper will summarize coal waste requirements under SHCRA, and also will review what operations at coal mines need to be controlled, in order to avoid potential liability under RCRA. In addition, it will mention requirements under other federal laws, including CERCLA, or the "Superfund" law,3 and describe how they may impose restrictions or liability on coal operations for waste or other materials commonly found at surface and underground coal mines.

Jan 1, 1993

By Roy H. Werner

The environmental demands on the mining industry coupled with rising production costs have created a need for a low cost sludge removal system. The HYDRA* system meets these demands by offering a unique means of removing settled solids from the bottom of a clarifier or a thickener. This underflow system combines experience and proven concepts to form a low cost sludge removal system. The HYDRA system incorporates a flexible design that can be adapted to any settling area. The components are readily available and cost less than a conventional clarifier or thickener. Existing technology developed by preparation engineers provides for retrieval and recovery of mine preparation plant refuse. However, past retrieval methods have been extremely costly. The HYDRA system, because of its low cost, makes the complete process of retrieval and recovery economically feasible. This allows wasted resources to be converted to a saleable product.

Jan 1, 1975

By G. Ferrara

To obtain a reliable comparison between conical and cylindrical separatory vessels used in dynamic dense medium separation systems, the following studies were made: (1) study of the swirling flow in conical and cylindrical vessels using laser-Doppler velocimetry (LDV); (2) study of the behaviour of suspensions of magnetite and ferrosilicon in water in both separators. It was found that: (a) the tangential velocity profiles differ in conical and cylindrical vessels: in a conical cyclone free vortex conditions affect the largest part of the vessel, while in a cylindrical vessel, the motion approaches that of a forced vortex, i.e. that of a centrifuge; (b) the conical vessel manifests higher centrifugal acceleration and very strong densifying; the density differential, and hence the density gradient inside the vessel is large; (c) the cylindrical vessel manifests lower centrifugal acceleration and low densifying, i.e. low density differentials, and hence, the density gradient inside the vessel is small; (c) due to greater densifying, the density cut-point in cyclones is higher than the operating medium density, while in cylindrical vessels the density cut-point is closer to the medium density. The results provide an interesting description of the differing behaviour of conical and cylindrical vessels and help explain the differences in performance between the two types of separators.

Jan 1, 1998

By Peter L. Dunn

With the advent of new high-strength magnetic materials, rare-earth magnetic separators have become more common place for processing heavy mineral sands. In many instances, rare-earth magnets have replaced conventional separators such as electromagnetic cross-belt and induced-roll type machines. This paper will present the results from a detailed test program developed to evaluate the performance of rare-earth drum and roll separators for processing heavy mineral sands. The effect of machine design parameters, such as magnetic element configuration and separator diameter, will be reviewed in light of these test results. The impact of basic operating parameters (i.e. feed rate and roll speed) on separation efficiency will also be presented.

Jan 1, 1999

By Didem Maral

Olivine is a name of a mineral group that has a chemical formula of: (Mg, Fe), SiO4. The most important rock for the olivine group minerals is dunite, which can contain olivine up to 95-99%. Dunite can be obtained from chrome enrichment as a by-product. As a result of alteration of the olivine group minerals, several kinds of different minerals can occur. Main consumption areas of olivine are steel and iron industry. Also olivine is used in not only casting and refractory industries but also production of radiator, ballast material and abrasive. North of Bursa-Orhaneli has got more than 5 billion tons reserves in ultrabasic massifs. M.T.A found that olivine has got high quality of using in refractory and casting industry.

Jan 1, 2005

By A. S. Henderson

Eastern Mesabi taconite is one of the hardest rocks known, but fortunately it shows little tendency to pack in the crushers, when the minus 5/16 inch material is removed. The crushing circuit is essentially as shown in the Engineering and Mining Journal article, "Reserve&apos;s New Taconite Project", dated December, 1956 except that the grizzly screen between the two stages of gyratory crushing has been eliminated. The Reserve operating staffs aim is to utilize the crushing equipment in such a manner that the maximum tonnage of taconite can be crushed to the required size at a minimum cost. As is readily apparent, the primary consideration is to produce a desired size product, with the other operating factors to be balanced, thus achieving the best setting for each crusher. Much effort has been expended toward the development of a satisfactory sized material for feeding the rod mills. The characteristics of this feed must allow the following situations to be handled by the existing equipment: 1. The material being fed to the rod mill must be such that it can be fed into the unit with the proper quantity of water to maintain the correct density within the mill. 2. The rod mill must produce a product from this feed which can be handled without difficulty by the magnetic cobbing and ball mill circuit. 3. The incidental tramp must not exceed that quantity which can be handled easily after the rod mill and after the ball mills.

Jan 1, 1959

By Dewa Putu Agus Sudarmaja, Widi Astuti, Januarti Jaya Eka Putri, Yayat Iman Supriyatna, Himawan Tri Bayu Murti Petrus, Siti Nurul Aisyiyah Jenie, Ferian Anggara, Anisa Maulidia, Vincent Sutresno Hadi Sujoto, Sutijan, Wayan Warmada

With the rapid development of renewable energy technology, such as electricity reserves to store energy for electric and battery-electric vehicles, environmentally friendly energy sources are expected to continue to be tapped to meet mobility and stationary energy needs. Lithium is the most attractive candidate for energy storage development. The presence of lithium in the Sidoarjo mud in Indonesia makes it interesting for use as an alternative source of raw material. In this research work, sulfuric acid was used as a solvent, and hydrogen peroxide as an oxidation agent. Lithium recovery was studied with a leaching process at various temperatures (30, 45 and 60 °C) and sulfuric acid concentrations (0.5, 1, 2, 3, 4 and 6 mol/L). Increases in temperature, sulfuric acid concentration and hydrogen peroxide concentration were found to directly affect the lithium recovery. An increase in sulfuric acid concentration is directly proportional to the recovery of lithium in the solution. Optimum conditions were obtained at a sulfuric acid concentration of 6 mol/L and temperature of 60 °C. The shrinking core model was used to study leaching kinetics, and ash layer diffusion acted as a rate-controlling process. The activation energy of the leaching process was found to be 38.90 kJ/mol.

Jun 1, 2024

By C. A. Fleming, K. W. Sarbutt, P. K. MacPhail

The SART process has been developed for Teck to treat bar­ren solution from the cyanidation/CIP process that has been developed for the Lobo-Marte project in Chile. The objective of the process is to recover cyanide in a form that is suitable for recycling to the leaching part of the process. The Marte and Lobo ore bodies require a dosage rate of about 2 kg/t NaCN, of which only 0.5 kg/t is truly consumed (as thiocyanate, cyanate and ferrocyanide species). The remaining -1.5 kg/t is present as cop­per cyanide (-1 kg/t) and free cyanide (-0.5 kg/t), and is poten­tially recoverable and recyclable. SART is an acronym that describes the unit operations in this cyanide recovery process; namely, .. Sulphidization .. Acidification .. Recycling of precipitate " Thickening of precipitate The basic chemistry has been applied previously, and has also been the subject of two patents (American Cyanamid Company, 1965, Potter et al., 1986). The process involves the conversion of all free and WAD cyanide in solution to hydrocyanic acid by acidification of the tailings solution to pH :s,4, and the conversion of all copper in solution to cuprous sulphide (synthetic chal­cocite) by the addition of a sulphide salt:

Jan 1, 1998