Search Documents

By Bruce D. Hulman, Robert .. F. Gorman

Introduction Groundwater resource evaluation has historically required extensive field investigative work, usually at great cost. More recently, the advent of the microcomputer has made difficult aquifer and groundwater evaluations comparatively simple and less expensive. A groundwater model is a numeric solution to a set of equations that calculates the water level in an aquifer or other types of water bearing strata. A computer will execute the solution of the set of equations rapidly and thereby permit evaluation of large amounts of hydrogeologic data rapidly. Computer modeling of groundwater resources is very often used to forecast the effects of multiple uses of a single groundwater resource. Modeling of heavily used aquifers has proven to be beneficial for averting problems arising from competitive use of a groundwater resource. This paper describes the work tasks performed in order to evaluate a large alluvial aquifer and thereby predict the hydrologic impact of additional groundwater withdrawal. Purpose and Scope Neyer, Tiseo & Hindo, Ltd. (NTH) was retained to evaluate the groundwater supply potential of the Missouri River alluvium underlying the Fairfax District in Kansas City, Kansas (Figure 1). The proposed groundwater supply is being considered for industrial use as non-contact process water and a heat exchange medium for plant climate control. The anticipated peak groundwater demand is estimated to exceed 30 million gallons per day (MGD) during the summer months, with an average daily demand of nearly 25 MGD. The proposed groundwater supply was to be developed from 15 large-diameter production wells located at positions that would minimize potential interference.

Jan 1, 1987

By Scott Jones, Tony R. A. Durkac, David W. Stephens

Williams Mine was considering spending a large amount of capital to install a pumping system underground to rid the mine of slimes; with the introduction of Delvo Stabilizer this challenge would be met. This paper will address the process to introducing the Delvo Technology into the Cemented Roddill Program. Some areas that were worked on included: testing of the mix design, bet dosage rate for an economical solution, temperatures at different levels of the mine, the amount of time needed once the grout was put to sleep, preventing plugs in the delivery system A controlled dosage that gave the Operator a 12 hour window of flowable material was developed and an added feature to the introduction of Delvo was also noted; an increase in MPa strength over the design. Collectively with the help of operators at the batch plant and the underground miners involved with the program all concerns where addressed and all goals met. A cost effective program was implemented thus increasing productivity, preventing costly plugs, and improved the actual maintenance on the entire delivery system, which included the batch tanks, aggitator tanks, all pumps required in the system and of course reducing buildup of slimes at the cones.

Jan 1, 2001

By T. Cohen

Technological innovation in the minerals industry must be driven by the need to improve performance according to social, as well as environmental, safety, efficiency and production criteria. This paper outlines the possibilities and rationale for incorporating constructive technology assessment into technology research and development within the CSIRO Minerals Down Under National Research Flagship (MDU). The paper develops a process of Social License in Design that attempts to address the future social challenges and opportunities of a technology during development by utilising forecasting techniques and accounting for the perspectives and values of decision makers and likely stakeholders. Interviews with senior technologists and social scientists within MDU reveal the institutional context into which the Social License in Design process is to be situated and highlight key factors that may inhibit or enhance its uptake.

Jan 1, 2011

By H. Soto, J. Jara, F. Nava, J. B. Hiskey, B. J. Scheiner

Laboratory tests showed that ozone can destroy free cyanide and weakly complexed cyanide (copper and zinc cyanides). The iron cyanide complexes were resilient to ozonation but they were effectively eliminated by precipitation with Fe (II) ions under controlled pH conditions. Tests carried out with effluents from a number of gold mills confirmed the results obtained previously in the laboratory. The industrial samples contained cyanide in the form of free cyanide and also complex copper, zinc and iron cyanides. Solutions that contained up to 184 mg/L total cyanide, after the ozone treatment analyzed only 2-3 mg/L dissociable cyanide and 50-90 mg/L CN(t) (accounted for by iron complexes). After precipitation with ferrous ions total cyanide was reduced below 1.5 mg/L. For most solutions ozone consumption ranges from 3 to 6 g per g of cyanide destroyed. However, certain impurities (such as SCN and S203 ), present in some effluents, increase ozone consumption and make it more difficult to reduce copper concentration to satisfactory levels.

Jan 1, 1993

By R. V. Ramani, K. V. K. Prasad

Forecasting mined grade variability from exploration information is a challenging task in mine planning. For effective planning of activities, such as workplace scheduling, ore grade quality control, etc., development of realistic numerical simulation models of in situ variability from exploration information is an essential first step. Geostatistical conditional simulation (GCS) is one of the well known methods to develop such simulations. Recently, stochastic fractal models based on the assumptions of scale-invariance and self-similarity have been used for developing simulations of several natural phenomena. It has been suggested that these models might permit the generation of short-scale variability information from exploration data with greater fidelity when the data satisfies the attendant assumptions. In this paper, stochastic fractal models are reviewed, and their relationship to geostatistical variogram models is examined. A comparison of the two simulation techniques has been performed using coal sulfur data from a mined-out coal property. The results of this comparative analysis are also presented in the paper.

Jan 1, 1993

By Zhe Liu, Liping Xiao, Jichi Bai, Xuefei Luan

"In order to study the removal efficiency of Cu2+ from acid mine drainage by prepared bentonite-steel slag composite particles, adsorption experiment was carried out. The composite particles were characterized by X-ray Diffraction analysis technique (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared spectrometer (FTIR). The results show that: the composite particles can release alkali to neutralize the acid of acid mine drainage; the adsorption and chemical precipitation of Cu2+ occurred in the whole reaction process; the removal amount of composite particles on Cu2+ was 9.88 mg/g when the reaction reached equilibrium; the FTIR spectra revealed the existence of surface complexation; the SEM micrographs suggested that the composite particles would continue to adsorb and coagulate Cu2+ after the composite particles surface adsorbing Cu2+ and forming precipitate, namely, there was synergistic reaction of adsorption and coagulation; the XRD patterns further showed the existence of cation exchange and revealed that the states of Cu2+ in the surface of the composite particles was Cu-Si-O mineral phase and CuO(Cu(OH)2) polymerization precipitation. The bentonite-steel slag composite particles which can play a role of adsorption-coagulation synergism are excellent multifunctional green environmental mineral materials to treat acid mine drainage containing heavy metal ions.Introduction It is reported (Zuo and He 2013) that with the rapid development of industry, the world demand for mineral resources is increasing, while the problem of mine environmental pollution is becoming more and more serious due to the large amount of mining. The pollution of mine wastewater has become a global problem, in which acid mine drainage (AMD) is one of the most serious waste water. It is also reported (Cong and Zhao 2003) that acid mine drainage containing high concentrations of heavy metals and having low pH value, causing serious negative influence to the mining production and ecological environment. Acid mine drainage is one of the most serious environmental pollution to the mining industry. In recent years, it has been widely concerned by scholars at home and abroad."

Jan 1, 2017

By G. V. Krishna Roa, G. Vijaya Kumar

One of the main objectives while planning ventilation systems for mines with multiple fans is minimization of the total airpower consumption of the mine. Solution of this problem by conventional ventilation network analysis programs is tedious and time consuming, and may not yield optimum results in all the cases. The paper presents an algorithm for solving multiple fan networks by finding optimum combination of fan operating points for required airflow distribution in the ventilation system.

Jan 1, 1995

By T. Eisele, T. Weldum, G. Rajala, H. Walqu, S. Kawatra

The throughput and energy efficiency of comminution circuits is reduced when ore characteristics change, causing bottlenecks in some portions of the circuit while leaving excess capacity in others. The results of analysis of three years of daily grinding circuit operating data for a full-scale plant has shown that the location of bottle-necks in the circuit will change depending on the nature of the feed ore. The circuit tends to be limited by the primary mill capacity when the ore hardness increases, and limited by the secondary mill capacity with softer ores. Two methods are considered for shifting load in the circuit to relieve bottlenecks by taking advantage of excess capacity in other parts of the circuit: 1) Addition of supplemental comminution operations, such as high-pressure grinding rolls, to process specific size fractions that are not handled efficiently by the primary mill; and 2) Use of screens to shift grinding load upstream from the secondary mills back to the primary mills. In the case of the plant examined in this study, it was found that 58% of the time there was sufficient excess capacity in the primary mills that the throughput of the circuit could have been increased by using screens to shift the grinding load from the secondary mills to the primary mills.

Jan 1, 2004

By M. C. Manderson

While the United States has been the world's largest volume producer and marketer of phosphatic fertilizers for many years, it has recently suffered heavy losses for a variety of reasons. While improved economic performance is expected, it is still at least a year or two away. But when recovery does manifest itself, it will likely yield only mediocre profits, due in part to the fact that about 50 percent of output is export-dependent. Therefore, there appears to be limited likelihood that profits will be adequate to justify the further outlay of large amounts of capital for expansion.

Jan 1, 1986

By James D. Bennett, David L. Passmore

The Coal Mining Section of the National Safety Council has selected hand and finger injuries of coal miners as a major topic for safety policy analysis [Tinney, 19851. So that facts about hand and finger injuries can be used to guide the Committee's work and the work of policy-makers, we present in this paper detailed analyses of the following factors related to hand and finger injuries received by coal miners between 1975 and 1983: occupations of the injured miners; activities of the miners when injured; machines involved; objects, substances, exposures, or bodily motions that produced or inflicted the injuries; principal physical characteristics of injuries; and events directly resulting in the injuries. We analyze hand injuries for underground and surface mines separately because of the remarkably different production methods and hazards evident in these two operating environments. We do not, however, provide information about hand and finger injuries that occurred in surface operations at underground sites (such as yards, shops, or tipples), auger mining operations, culm banks, dredging operations, mill or preparation plants, offices, or laboratories. The most comprehensive information about the safety of coal mining in the United States is assembled by the Health and Safety Analysis Center (HSAC) of the Mine Safety and Health Administration of the United States Department of Labor. Mine operators in the United States report to HSAC all injuries as required under Part 50, Title 30, of the Code of Federal Regulations (mandated by Section 103 the Federal Mine Safety and Health Amendments Act of 1977, Public Law 95-164). These regulations stipulate that injuries must be reported within ten days of their occurrence on a United States government data collection form, Mine Accident, Illness and Injury Report (MSHA Form 7000-1). HSAC maintains these data primarily to produce federally-mandated reports. HSAC resolves injury reports that are incomplete, checks for errors in data coding and handling, and corrects inconsistencies in data submitted by

Jan 1, 1986

By Ezra L. Kotzin

Foundry sands used to make molds and cores have been very important to foundrymen since metal casting began hundreds of years ago. They are now used in two basic ways, either in an uncured green state, grain-bonded with clay, or in a set cured state achieved with sand that, mixed with resins or oils, is cured by baking or by chemical reaction. The term sand, as generally used in foundry applications, may best be defined as material composed of granular particles of mineral matter, ranging in size from 0.5 to 2 mm in diameter. The particulate nature of the material may be the result of natural disaggregation or result from crushing and screening of rock or ceramic materials; crushed and screened products are sometimes referred to as "manufactured sand." Based on their origin, the raw materials for foundry sands will vary in grain shape, grain composition, relative surface, grain size, and grain distribution patterns. These properties, in addition to their chemical analyses, sintering point and expansion characteristics play an important part in the choice of sands used as the base molding or core aggregate in metal casting. Sands with different origins may be blended to produce specific compositions and grain size distributions. Early raw material requirements based on silica sand were simple, but as sand/core/mold technology became more sophisticated and binder technology continued to be developed, the physical properties of foundry sands became more critical. Silica sand is composed of quartz, along with, in most cases, small amounts of feldspar, mica, clay, and other common minerals. Although silica sand is still by far the most widely used base material in production of molds and cores used in metal casting, other natural mineral sands have their own unique characteristics and fill an important niche in special applications. As a result, the term sand, as applied to raw materials used in metal casting, has been logically extended to include granular materials composed of a group of minerals other than quartz. With increased use in advanced foundry technology, natural sands composed predominantly of zircon, chromite, staurolite, or aluminum silicate minerals and of granularized chromite or olivine, have become more than just alternate materials and are now commonly classified as sands when the grains are sand-sized. Foundry sand may therefore be considered under two categories: silica sands and non-silica sands.

Jan 1, 1994

In this presentation, CiDRA?s patented technology platform and its applications will be described. CiDRA's non-invasive, passive sonar array-based flow meter technology provides the volumetric flow rate of single or multiphase fluids by measuring the speed at which naturally occurring structures such as turbulent eddies or density variations convect with the flow past an axial array of sensors. These sensors are incorporated in a band that is wrapped around the outside of the pipe, resulting in no process downtimes for installation and unprecedented reliability. This technology has resulted in a unique ability to measure the flow rate of most fluids ? clean liquids, high solids content slurries, pastes, and liquids and slurries with entrained air. Unique and difficult minerals processing flow measurement problems and their solutions will be described. Examples of these problems include flow measurements in froth lines and flotation feed lines with entrained air, slurry lines with magnetite and other magnetic ore, slurry lines with abrasive or corrosive materials, high pressure lines, and lines exhibiting scale buildup. Recent technology developments will be covered.

Jan 1, 2008

By A. K. Bakshi

In cold regions, rinsing of spent cyanide from leach heaps is stopped during winter and is resumed again after the snow melts. The effect of this idle time on the overall removal process was studied in this experiment. Samples were collected for rinsing tests from one heap at a gold mine near Fairbanks, Alaska. Continuous and interrupted rinsing of this sample were carried out in test columns. The rinse solution was analyzed at regular intervals to determine the rate of cyanide removal from the solids. It was found that total cyanide concentration per rinse cycle for interrupted rinsing test was higher than for the corresponding continuous rinsing test. As a result, interrupted rinsing required less rinsing cycles than continuous rinsing.

Jan 1, 1995

By I. E. Odom

The physiochemical properties and industrial uses of the clay mineral montmorillonite are reviewed. Montmorillonite is the most abundant species of the smectite clay mineral group and is the predominant mineral composing bentonite deposits. The crystal structure, chemical composition, exchangeable ion type, and small crystal size are responsible for several unique properties, including a large chemically active surface area, a high cation exchange capacity, and interlamellar surfaces having unusual hydration characteristics. The type of exchangeable ion, sodium (Na), calcium (Ca), and/or magnesium (Mg), has a major influence on industrial and chemical uses of montmorillonite because of their hydration characteristics. Natural occurrences of Na mont¬morillonite in commercial quantities are geographically limited, but Ca-Mg montmorillonite deposits are known worldwide. Foundry, well drilling, pelletizing, and civil engineering constitute the major uses of montmorillonite, but the total array of uses exceeds that of any other mineral.

Jan 1, 1988

By R. L. Grayson, L. L. Probert

A three-year project focusing on the depth profiling of respirable coal mine dust particles using scanning electron microscopy coupled with energy dispersive X-ray analysis resulted in the development of statistically classified particle-behavior models. The models depict the changing silicon fraction for particles at 5-, 7-, 9-, and 11-keV accelerating voltages, thereby giving a clear indication of the nature of various types of mineral particles. This paper focuses on the results for respirable quartz particles sampled from five underground coal mines across the US. Through statistical analysis of results the relationship between the fraction of surface available quartz in respirable dust samples and coal rank is established for three Pennsylvania coal seams.

Jan 1, 1995

By A. D. Davis

The historic Homestake Gold Mine at Lead, SD, was closed in December of 2001, after 125 years of operation. Since closure, the mine has been selected by the National Science Foundation as the proposed host site for the Deep Underground Science and Engineering Laboratory. Pumps in the 8000-ft deep mine were shut off on June 10, 2003. Post-closure flooding of the mine has resulted in rising water levels that reached the 5000-ft level in July of 2007. The rate of water inflow into the mine is about 750 gal/min. A plot of water level vs. time shows that the rise has not followed an exponential decay curve. When the pumps are turned on for dewatering, the rate of water-level decline will be monitored. Water in the Homestake mine contains arsenic derived from arsenopyrite. In samples of mine water, the median concentration of arsenic was below the surface-water aquatic life standard for beneficial use.

Jan 1, 2008

By L. Xu, R. Bhaskar

While a NIOSH accepted procedure exists for determination of quartz in the respirable dust samples from coal mines, no specific procedure has been defined for quartz determination in bulk samples. In this study, the effect of particle size on the estimation of quartz using the infrared technique was evaluated. Several laboratory tests were performed to determine the dependence of the infrared absorbance peak height on the different sizes of quartz particles. The significant dependence observed between quartz particle size and the measured peak height indicates the potential for erroneous interpretation of the quartz in bulk samples depending on how the samples are prepared. A procedure to reduce the effect of size in the determination of the quartz content is suggested.

Jan 1, 1994

By Henry P. Ehrlinger III, Latif Khan, John M. Lytle

The primary purpose of this project was to produce and test coal concentrates made from coal preparation plant waste fines for use in a slurry-fed gasifier. Concentrates from several individual waste streams were examined to determine their amenability as feedstock for a slurry-fed, slagging, entrained-flow gasifier. The tests included analyses of the plant feed and product, material balances, and estimates of gasification reactivity and of pumpability. The following preparation plant fines were examined: • fresh rejects produced in a plant processing underground- mined Springfield Coal • fresh rejects produced in a plant processing underground- mined Herrin Coal • fresh rejects produced in a plant processing surface-mined Springfield Coal and Herrin Coal • Five-year old impounded fines rejected during processing of underground mined Herrin Coal. At high coal recoveries the Btu content of the concentrates was greater than the Btu content of the utility product from the plant. The coal recovered from fines was found to be entirely acceptable for gasification and pumping without additives.

Jan 1, 1995

By Bryce T. Tripp

Utah's abundant industrial rock-and-mineral resources support a relatively small but important sector of the State's economy. In 1983, six of the top 10 nonfuel mineral commodities (by value) were industrial commodities. Portland cement was ranked fourth, potash fifth, halite sixth, phosphate seventh, construction sand and gravel eighth, and lime tenth. Portland cement was produced by three operators, principally from the Jurassic Twin Creek Limestone. Potash was produced by three companies from Pennsylvanian beds in the Paradox Basin, surface brine of the Great Salt Lake, and subsurface brines of the Great Salt Lake Desert. Halite was produced by eight operators, primarily from surface brine of the Great Salt Lake. Additional production came from salt beds in the Jurassic Arapien Shale, solution mining of the Pennsylvanian Paradox Formation of the Hermosa Group, and subsurface brines of the Paradox Basin. Phosphate was mined by one company from the Permian Meade Peak Phosphatic Shale Member of the Park City Formation. Construction sand and gravel were produced by dozens of operators, primarily from Quaternary Lake Bonneville beach and nearshore deposits. Lime was produced by four operators from Paleozoic formations in the Basin and Range physiographic province of Utah. The future production of these and other industrial commodities, though individually uncertain, is expected to increase gradually as a group. Factors favorable for the future of the industrial commodities industry in Utah include large to almost unlimited resources for the major commodities, a healthy projected population growth, an abundant local supply of relatively inexpensive energy from coal and natural gas, and a favorable corporate tax structure and business climate.

Jan 1, 1987

By D. Krzyszton, P. Czaja

Mining explosions in rocks originate stress waves of great intensity, which crush the surrounding rocks and are then propagated as a seismic wave. Seismic waves are the cause of dynamic loading of pillars and their subsequent destruction. In calculating safe dimensions for inter-room pillars, not only the stresses conditioned by overburden pressures should be taken into consideration, but also the dynamic stresses caused by explosion. This is of particular importance for pillars with great specific acoustic impedance which have been destroyed mainly by the reflected seismic wave. It is possible to take dynamic loading into consideration in the calculation of pillars when the parameters of the propagation wave, the dynamic elastic constants of rocks, the strength properties of rocks, the strength properties of rocks subjected to dynamic loads and the parameters of the blasting charge are known. An example of the calculation for the safe width of an inter-room pillar subjected to the seismic effect of an explosion is given and the possibilities of reducing the dynamic loading of pillars are discussed.

Jan 1, 1982