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By L. Bratek, K. Jaworek, M. Czaplicka

Methods for arsenic compound removal from aqueous solutions include processes such as: coagulation, adsorption, membrane techniques, electrochemical and biotechnology techniques. Advanced oxidation using both UV radiation and strong oxidizing agents such as ozone and hydrogen peroxide may also decompose these compounds. It is known that effluents from metallurgical processes contain inorganic arsenic compounds in addition to the organic compounds such as: dimethylarsinic acid and phenylarsonic acid. This paper presents the conditions that lead to the formation of deposits containing mainly arsenic, such as pH, the wavelength of the radiation and the type of oxidant, for this type of effluent.

Jan 1, 2014

By Christie GB, Mainwaring DE, Leong YK

High solids brown coal slurries have been prepared with concentrations approaching those achieved with bituminous black coals. The high inherent water content and macroporosity of Victorian brown coals have been reduced in a controlled manner by chemical and mechanical means. The hydrophobicity of the coal surface has been increased sufficiently to reduce the tendency for swelling and water uptake. This together with densification has allowed the solids content to be progressively improved from 25% solids with raw coal to 65% solids with modified coals. Both raw brown coal and modified brown coal suspensions show shear thinning behaviour resulting in lower viscosities at higher flow rates. All coal suspensions displayed a yield stress once sufficient solids concentration was achieved. This yield stress can be used in the prevention of solids settling. Under simple shear mixing the network structure that provides the yield stress quickly breaks down to a low viscosity fluid with reduced yield stress and a pumpable consistency. The time necessary for structural recovery is in the order of days permitting shut-down and start-up of fuel delivery systems.

Jan 1, 1987

By M. J. Gavin

Within the past three years numerous inquiries for information on oil shale have been received by the Bureau of Manes. These inquiries have been increasing to such an extent that it has seemed advisable to issue a short paper prior to the publication of a bulletin on the subject, giving a, general discussion of the subject and a comprehensive list of references, so that those interested in the details of obtaining oil from shale can find additional information without much difficulty. Some of those who desire information are interested only in a general discussion of the subject, or are not in a position to refer to books and' articles describing the industry. The material for this paper is largely derived from published information on oil shale. Much of the information is obtained-from the books and articles mentioned in the list of references, and has been compiled with the intent of furnishing information to those not interested in all the details.

Jan 1, 1921

By P Klaric, N Swart, S Barnes

The recent advances in digital imaging technology, specifically around photogrammetry, have facilitated precision measurement in the difficult conditions encountered in an underground development mining environment. With the recent downturn in the resources industry, many mining houses have begun to focus on cost reduction projects and driving efficiencies. The application of digital photogrammetry has allowed greater insight into the development mining cycle and supported a focus on areas where efficiencies and cost savings can be achieved. Data collation, via digital image capture, can be completed with minimal disruption to the development mining cycle with analyses taking a nominal time to process and interpret. The result can be a stark visual representation of the result of blasting and associated activities of the development mining cycle. Many millions of dollars of benefit can be derived from understanding the impact of each component of the development mining process, with some of the biggest savings associated with conformance to drill design and the minimisation of overbreak during blasting. This paper will explain the image capture process, analyses and instigated improvement opportunities that were undertaken at a number of mine sites to improve efficiencies and drive savings in their development mining processes.CITATION:Klaric, P, Swart, N and Barnes, S, 2017. Digital imaging provides valuable insights into underground development mining, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 129–134 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

Polish coal mines are well equipped with methane monitoring systems,nevertheless the worsening conditions force a continuous impro- vement in the field of environmental monitoring. Application of modern electronic components make it possible to design the new modular telemonitoring system incorporating the best features of the older systems,widely employed in Polish collieries, eliminating their weak points. Several new sensors and portable instru- ments for methane monitoring and early fire detection have been developed and tested in mining conditions.

Jan 1, 1988

By Hargraves AJ

Pre-drainage experiments have been conduct- ed at Appin, Cook, John Darling, Leichhardt, Macquarie, Metropolitan and Moura No. 2 Collieries. Appin (550 m deep) experiences particular gas problems in development drivages, and the almost pure CH4 seam gas makes difficult tiro compliance with statutory maxima in intakes and returns. Patterns of 43 mm diameter drain- a,.;e holes drilled ahead and laterally into virgin coal have improved gas conditions in working places and have allowed tolerable advance rates. Cook, Leichhardt, Metropolitan and Moura No,. 2 Collieries have experienced gas and stress phenomena ranging from conical bursts less than one tonne to full scale instantan- -us outbursts of hundreds of tonnes with tens ,f thousands of cubic metres of seam gas. Gas ~Irainage experiments with patterns of holes up a,, 200 mm diameter have been undertaken with ;,;siness monitors on the coal to establish .lative effectiveness. Incremental flows into mg 43 mm diameter boreholes have investigated drainage patterns relative to length, and at comparative incremental flows have nlicated lowered permeability zones at stress ,.,utments. In some CO2 seam gas areas where iammability problems are reduced to perhaps ii, but where outbursts proneness is increased,

Jan 1, 1982

By George L. Gates

It is generally recognized that if the lose and contamination of the fluid content of a core specimen from an oil- and gas-bearing formation in a well were eliminated, the value of core analysis would be increased greatly. In an effort to obtain uncontaminated cores, extensive field tests were carried out in the Mercy field, San Jacinto County, Tex., with the Carter pressure core barrel and an oil-base drilling fluid having very low rates of filtration as measured by the standard A.P.I. drilling-fluid filter teat. A tracer was added to the drilling fluid filter test. A tracer was added to the drilling fluid to provide a means for quantitatively measuring the volume of oil filtrate in the cores. Unfortunately, as stated in the report on the Mercy tests, very little oil nand was penetrated in coring the well; and because the performance of the pressure core barrel was not entirely satisfactory, the tests did not provide a complete answer to the question: Does a filtrate from an oil-base drilling fluid enter cores., and how does it affect the results of the core analyses?

Jan 1, 1950

By C. A. Herbert

The mine of the Alpha Portland Cement ..Co., Iroaton, Ohio, ..working in. a. bed of limestone 96 feet thick at a depth of approximately 510 feet below the surface, has established a won¬ derful safety record, having operated 6 years—frcra September 21, 1926,. to September 21, 1932 - without a lost-time accident. This mine, with 61 to 86 employees (average 68) and daily output of 1,000 to 1,200 tons of limestone, operated 1,041 days during the 6-year period, or the equivalent of 578,894 man-hours of exposure. ...... ... . Immediately above the limestone is a 20-foot .bed of hard..sandstone.. At present about 10 feet of limestone is left up as. a roof and.about. 42 feet is being extracted. Of the lower portion of the bed it is believed that about. 25 feet. ..immediately below . the .present workings is suitable for cement and will be extracted later. The mine workings are reached by two rectangular concrete shafts, one a 2-compartment hoisting shaft and the other a 2-compartment air and escape shaft- In the latter shaft one compartment is used as an airway and the other, as a cage compartment fo.r a man and material cage. .. . - . The tipples at both the air shaft: and. hoisting shaft are-of steel. The.ground landings at both shafts are fenced in with hand-operated gates in front of the cage compartments.- The two shafts and the crushing plant, which .is.a part of the hoisting shaft-tipple structure, are adjacent to the mill buildings. The rock is hoisted on self-dumping cages in 4 ton capacity, end-gate, steel cars. An electric hoist with automatic overwind device is used at both the main shaft and air shaft. The controls for the main hoist are in the tipple where the engineman is stationed and from which point he has an unobstructed view of both the ground, landing and the cage coming into the dump.

Jan 1, 1933

By S. C. Tadolini, J. M. Goris, J. L. Gallagher

Cable supports offer several advantages over traditional secondary support methods by enhancing stress redistribution to pillars and gob areas, minimizing or eliminating timbers and cribs that reduce ventilation, eradicating material-handling injuries related to placement of crib supports, and providing a cost-effective alternative to secondary support. The U.S. Bureau of Mines (USBM), researching alternatives to traditional roof support methods, designed and installed high-strength cable supports to improve the stability of longwall gate road entries in a western U.S. coal mine. With the cooperation of industry, methods were developed to install and evaluate cable supports in a tailgate area using traditional resin cartridges. The cable-bolted areas successfully maintained roof support throughout the developed entries. Cable supports have replaced wood cribbing as secondary support in the bleeder entry system and have minimized or eliminated the use of cribbing in the longwall tailgate entries. This paper describes the theory, application, and advantages of cable supports and presents some mine measurements made to assess the cable performance during the retreat process of longwall mining.

Jan 1, 1999

By A. Rao, J. A. Davidson, B. L. Jones, K. W. Bowes, D. Craib

Supported by ANSTO, Groundwater Science and Inception Consulting Engineers, Boss has embarked on a series of technical projects aimed at reinforcing the Project’s capability to meet its export permit production capability. This paper will focus on three aspects of this technical program: Reducing the cost of resource expansion through smart use of low cost, surface target generation techniques; Improving the rate of uranium leaching and solution stability (gypsum, jarosite) through lixiviant chemistry modifications; and Development of an ion exchange (IX) process to increase production capacity, and integration of IX and the current solvent extraction circuit with the existing uranium precipitation and product preparation circuits.

Jan 1, 2020

By Eric J. Foell

Recognizing that the planned commercial exploitation of polymetallic nodules in the deep sea should be accompanied by environmental studies in order to protect this largest and least understood ecosystem of our planet, the German Ministry for Research and Technology has since 1989 funded a longterm and large-scale disturbance-recolonization (DISCOL) experiment in the abyssal Peru Basin of the equatorial South Pacific Ocean. The circular study site is located at 4150m depths and encompasses about 10km2 of relatively flat, heavily sedimented sea floor with low (< 15%) nodule coverage near an existing German nodule mining exploration license area. The RV SONNE, a large and well-equipped multi-purpose research vessel, served as platform for all environmental cruises conducted to date. The initial DISCOL expedition (SO-61, Feb.-March 1989) was carried out in two legs. During DISCOL 1/1, a study site was selected, a pre-disturbance baseline assessment was undertaken, and sea floor disruption was begun using the "plow-harrow", a uniquely designed disturber device towed repeatedly across the circular study area. During DISCOL 1/2, disturber deployments continued until the device had created 78 criss-crossing and partially overlapping tracks along which nodules were essentially plowed under while sediment from up to 15cm below the seabed had been turned over and exposed at the surface. In addition to the obvious within disturber track impacts, sediment mobilized by plowing drifted off with the prevailing near-bottom current and redeposited downstream, blanketing nearby areas not directly disturbed. Immediately after the disturbance phase, an initial post-impact sampling series was performed. The DISCOL Experimental Area (DEA) was revisited about six months (DISCOL 2, SO-64, Sept. 1989), three years (DISCOL 3, SO-77, Feb. 1992), and seven years (ATESEPP SO-106, Jan.-March 1996) after disturbance to collect further post-impact samples, monitor changes in the benthic community and follow the recolonization process. In addition to benthic community studies, plankton investigations were initiated during the third DISCOL cruise (SO-77) and continued during three further cruises (SO-78, SO-79 and SO-80/2) in 1992.

Jan 1, 1996

By T BoBo, D La Rosa, P Cameron

Efficient pre-concentration using natural and induced deportment starts with effective blast design. Leveraging these characteristics using Size-Based Grade Engineering® techniques requires detailed understanding and measurement of the particle size distribution (PSD) of the Run of Mine (ROM) ore. In turn, blasts must be designed to optimise fragmentation for the pre-concentration method. To be successful, fragmentation outcomes must be predicted and measured as part of the blast design process to account for the response ranking of the rock mass. The upgrade achieved using Size-Based Grade Engineering® methodologies will rely on the proportion of feed that reports to the screen undersize, so particle size distribution of the feed stock is of paramount importance if the potential benefits are to be achieved and maintained. Measuring actual fragmentation in the ROM ore and comparing with predictions allows the modification of subsequent blast designs to optimise fragmentation for pre-concentration scenarios. Automating this process can deliver significant increases in productivity and mine site profits. This paper discusses the importance fragmentation plays in Size-Based Grade Engineering® and explores technologies and methodologies used to measure it, consistently ensuring the best outcomes.

Nov 10, 2020

By M. D. Aldridge

This document reports the results of a two-year research effort aimed at improving communication systems used in coal mines. This work was conducted under a program whose original goal not only involved the development of practical and effective electronic systems for operational communications, but also for monitoring, at a central location, remote instruments at key positions in a mine. About half way through the originally proposed three year effort, the program was redirected to phase out the communication effort at the end of two years and to concentrate the program" resources on the investigation of new monitoring system concepts developed by this research. Thus, the work reported here is incomplete relative to the originally pro- posed program. However, the work was carried to the point of providing sufficient evidence to aid in the comparison of certain new communication concepts. For the concepts chosen for this study, the work was stopped short of hardware development and field testing, Several reports in the form of Master&apos;s theses and a Doctoral Dissertation have resulted from this research. They each report in considerable detail the results of several individual" contributions to this program. In preparing this report, an attempt has been made to provide a complete description of the significant results but with- out burdening the reader with the minute details. These more detailed reports are referenced heavily for the convenience of those interested. PRESENT COMMUNICATION METHODS Two types of communication systems are presently used In coal mines. They are: 1, Various forms of telephone systems, and 2. Carrier current radio systems using the trolley line as the interconnection circuit. Carrier current radio is used almost exclusively for control of rail trafflc by the dispatcher. Almost all other communication uses the telephone system, Telephone lines generally extend to areas where trolley lines are not present such as the outside offices and warehouse. Therefore the telephone system provides the primary means of voice communication. Telephones - Telephone systems employed in American coal mines fall into three categories. 1. Paging type telephone systems - these systems have individual stations which use battery powered transistor audio amplifiers to boost signal levels for normal communication. When in the page mode,

By A. L. W. Lips, B. P. J. Stevens, T. J. R. Barclay, E. Rothery, S. H. White

Discussion by B.P.J. Stevens of the paper, published in Trans. IMMA, vol.104, 1995, p.B1-B17, is presented together with the authors' response. Stevens questions the authors' radically different interpretation of the structural geology of the Broken Hill Block, considering that the descriptive part of the paper is a useful addition but that the conclusions are unwarranted on the basis of the data presented. A number of major points of disagreement are outlined and half a dozen additional minor points listed. In response, the authors admire Stevens's contribution to unravelling the geology of the area but defend their attempts to take the regional studies a step further, pointing out that he has misquoted what they wrote and arguing that because of the assumptions underpinning the derivation of the present stratigraphy it cannot be used to constrain structural models. With regard to shear zones, they cite the extensive earlier literature and refer to horizontal displacements shown on maps produced by Stevens et al. Detailed discussion follows of the stratigraphy and of the stratigraphic correlation problems resulting from failure to recognise the presence and significance of shears, particularly those parallel to stratigraphy. The remobilised position of the Pb mineralisation in the North Mine open cut is reiterated. It is concluded that there is an urgent need for systematic isotopic dating in the area to constrain the stratigraphy

Apr 1, 1996

By R Schmitt, Y Ghorbani, I McElroy, N J. Bolin, M Parian

Aitik is a large copper porphyry type deposit located in northern Sweden, currently exploited at an annual rate of approximately 45 Mt. The ore’s exceptionally low head grade of 0.25 per cent Cu and varying degrees of hardness across the entire deposit pose challenges to the two fully autogenous grinding lines, each of which comprises a primary autogenous mill in series with a pebble mill. The variability in ore grindability frequently leads to fluctuations in mill throughput. Within the framework of a geometallurgical approach, the present study investigated the relationships between ore grindability and modal mineralogy. For this purpose, drill core samples from different lithologies were subjected to Boliden AB’s in-house grindability tests. This fully autogenous laboratory-scale test generates a grindability index mainly related to abrasion breakage, which is a significant breakage mechanism within autogenous mills. The test results suggested divergent degrees of grindability within and across the selected rock types. A combination of scanning electron microscopy, X-ray powder diffraction, and X-ray fluorescence analyses was performed for the grinding products and bulk mineral samples. The resulting mineralogical and elemental properties were subsequently correlated to the parameters from the grindability tests. It was shown that the main mineral phases, such as plagioclase, quartz, and micas, correlate well with the grindability indices. Similar correlations were found regarding the sample’s chemical composition, attributable to the main mineral phases. A further inverse correlation was established between the sample’s calculated average Mohs hardness and the grindability indices. Moreover, mineral liberation information provided by scanning electron microscopy was associated with the parameters mentioned earlier. The identified relationships between grindability, modal mineralogy, and element grades may help Boliden develop a predictive throughput model for Aitik based on the mine’s block model.

Aug 24, 2022

By Mukesh Jain

The liquor from potroom wet scrubbers is treated with lime to precipitate the soluble fluorides. The solids after filtration, referred to as scrubber mud, contain in addition to calcium fluoride, alumina, carbon, tars including polyaromatic hydrocarbons (PAH), cryolite and pachnolite and are considered hazardous. This communication deals with the pilot plant scale calcination of scrubber mud with a rotary kiln to obtain non-hazardous fluoride raw materials. Air classification was performed to separate the mudinto aluminarich andcalcium fluoride rich fractions which were then calcined. With proper control of calcination parameters and addition of lime, the carbon and tars were destroyed and hydrogen fluoride emissions were controlled. The calcined products could be used in the steel indusny as a fluxing agent or as a substitute for fluorspar in the production of aluminum fluoride.

Jan 1, 1994

By Allan MacRae

Freeport-McMoRan Inc. operates an ISASMELTTM furnace for the smelting of copper concentrate at the Miami Smelter in Claypool, Arizona. In May 2017, the furnace was restarted after incorporating newly designed copper cooling elements from just above the tap hole to the underside of the roof. The objective of the improved cooling design was to extend campaign life by eliminating existing failure mechanisms with the wall refractory. In addition to upgraded bathline coolers and complete coverage of the gas offtake transition, or ‘kettle’, with plate coolers, a novel arrangement of coolers was installed in the remaining freeboard area. The shell required significant cutting and re-stiffening, as well as extensive modification of the cooling water piping. Based on performance observed to date, it is expected that smelter throughput will be increased due to extended ISASMELTTM refractory campaign life.

By S. R. Zimmerley

Recent investigations of finely ground materials have verified Rittinger&apos;s law of crushing.4, This law states that the surface produced is proportional to the work expended in the crushing operation. Thus, for a unit of work applied to crushing quartz a definite amount of surface will be produced. Obviously, this amount of work applied to some other mineral will not produce equivalent surface. It follows that in an investigation of mill practice, where ore is being crashed, the relative crushing resistance of the component minerals must be known. In a previous investigation of the Rittinger law,5 the crashing resistance that is, the work required to produce a unit of surface - was accurately determined for quartz. The surface values were obtained by means of the rite of dissolution of quartz in hydrofluoric acid.6 If it were possible so to measure surface on other minerals the determination of relative crushing, resistance would be a simple matter; however, the results obtained on minerals other than quartz by a dissolution method were not encouraging. Moreover, if accurate values could be obtained by dissolution this method could probably never be used on a mixture of minerals such as occurs in an ore.

Jan 1, 1929

By D. Visser

This paper is based on the Townlands Ore Replacement Project whereby the concept of conventional sinking of one large diameter shaft was declined and replaced with three smaller raise bored shafts. A wire line geophysical survey was done and the results indicated that a single shaft larger then 4 m diameter unsupported would not be suitable. The shafts were placed 28 meters apart measured from centre to centre. To ensure that the skin to skin pillars between the shafts remained regular and to minimise any deflection, the pilot holes were drilled with the Rotary Vertical Drilling System. The different shaft sinking methodologies are discussed explaining the risk associated with each method.

Jan 1, 2009

By D Tuazon, M Powell, M Ziemski, G D. Corder

Although mining companies have made broad corporate-level commitments to adopt sustainability, there continue to be problems when attempts are made to adopt higher-level sustainability aspirations and translate them into appropriate targets and methods at the more-specific operational level. The integration of sustainability principles into minerals processing operational decision-making processes has unique challenges that are not addressed adequately by current tools and methodologies, yet impacts from operational decisions can have longer-term effects realised at closure and rehabilitation.This paper describes a proposed methodology to achieve the integration of sustainability at the operational level through a systematic and rigorous process of identifying and qualifying sustainability issues and opportunities in an operation. The methodology, starting from a sustainability point of view rather than an operational one, guides the identification of process issues and opportunities by examining the operation, unit-by-unit, similar to a Hazard and Operability (HAZOP) process. Each issue or opportunity is qualified according to its measurability, scopes of impact and consequences so that it may be understood fully and the correct engineering problems are formed. Through improved decision-making to account for broader sustainability factors, operations can better address environmental and social expectations and pressures (both corporate and community, as well as immediate and in the longer-term), whilst still delivering on operational and business goals.The methodology has been tested with two case studies at minerals processing operations. At one site, the methodology identified a dust issue which had considerable business risks (loss of valuable product) compared to conventional engineering analysis processes. The other site also benefited from using the methodology as an opportunity to improve the operation of the milling and flotation circuits was identified. The opportunity not only showed a potential to improve operational efficiency, but also potential improvements in water and energy efficiency and a resulting increased resilience against water and energy supply risks. It was important to utilise the holistic approach of the methodology in the identification of opportunities at this site; the goals of the operation showed a strong coupling between water and energy issues which would be difficult to overcome using the operationÆs current organisational model, which deals with such issues separately of each other.CITATION:Tuazon, D, Corder, G D, Powell, M and Ziemski, M, 2012. A practical and rigorous approach for integrating sustainability principles into decision-making processes at minerals processing operations, in Proceedings Life-of-Mine 2012 , pp 233-242 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012