Search Documents

By B P. Banerjee, D Patra, S Raval

Roof bolts are an essential component of roof support systems in underground mines. They are used to provide structural support to the roof of the mine and prevent it from collapsing. Therefore, it is imperative to perform regular assessments of these roof bolts to avert any hazards. Manual investigations of roof bolts are done by surveyors in underground mines, which is extremely timeconsuming and challenging due to the low-light conditions in underground mines accompanied by stringent mine access rules. To this end, automated recognition of roof bolts in 3D point cloud data obtained through laser scanning in underground mines serves as a potential solution to aid roof bolt monitoring. With the continuous advancements in laser scanning-based 3D data acquisition systems, the feasibility of making such surface estimations from 3D point cloud data has increased severalfold.

Sep 1, 2024

By Hughes J. C

THE smelting plant consists of five large furnaces operating in the treatment of current flintered material, and one small furnace operating periodically in the treatment of copper dross and antimonial slag produced in the lead-refining process.he following table supplies the leading dimensions and details of the large furnaces:-(a) Crucible - Dimensions 17 ft. 2 in. long x 4 ft. wide x 2 ft. 3 in deep. Capacity - 30 tons lead. Class of lining - firebrick. No. firebricks required - 3000.(b) Crucible Tank - Dimensions 20 ft. 6in. long x 10 it. 6 in. Wide x 4 ft. 3 in. deep. Material - 1/2 in. mild steel.(0) Jackets - Dimensions 6 ft. long x 19 in. wide x 6in. thick. Material - Cast-iron. Average life - 2 years. Number per side - 11, with 13-in. bosh. Number per end - 3, with 9-in. bosh.

Jan 1, 1922

By B M. H Sharp, R P. Hide, S P. Devine

Uncertainty and debate currently pervade the mining industry in New Zealand. The operational uncertainties, whether external (eg gold prices, the exchange rate), or internal (eg coal expansion difficulties), are large. In addition, many wider factors which influence mining are in a state of flux. State Coal Mines, the operating branch of the Mines Division of the Ministry of Energy I may be made a state corporation, with the remaining Mines Division functions being revamped. The agencies administering environmental legislation are to be restructured. Mining legislation amendments have been proposed and then dropped, and the area is now to be reviewed (The Press, 31 July 1985). Some mining licences have been withdrawn, and become the subject of heated debate in the community (The Press, 19 July 1985, and subsequent letters to the editor).

Jan 1, 1985

By Payne AR

The high cost of gateroad repairs and maintenance in U.K. longwall coalmining is a clear indication of the failure of permanent support systems to fulfill their prime function, i.e. control of strata movement. The main component of gateroad support is the pack, the design and materials of which have experienced an important development process during the last 10-15 years. More recently, research investigators have attempted to give a design basis to pack quality and dimension, and reference is made to two theoretical approaches. In the course of a current research programme based upon in situ monitoring, interim design recommendations have been proposed as a means of effecting improvement in support efficiency. Identification of characteristic deformation behaviour forms the basis of the recommendations made and the subsequent improvement in gateroad performance reported.

Jan 1, 1986

By Fukui M

An increase in pig iron output by 50 per cent was aimed at after re-lining No.2 blast furnace of NAKAYAMA STEEL WORKS. This had to be achieved by increasing both the furnace volume (from 673 to 757 m3) and its productivity, Without equipment for high top pressure operation, high productivity was mainly attained by the following three measures; (1) improving the gas flow characteristics by maintaining a high ratio of agglomerated ores, increasing the strength of sinter and coke, and optimizing the charge distribution, (2) decreasing the fuel ratio by low Si operation and the use of hot blast, and (3) oxygen enrichment. In addition, the tapping controls for pig iron and slag were intensified. As a result of the above measures an excellent hot metal output of 2.7 tonne/m3/day was attained in April 1979 (monthly average).

Jan 1, 1980

By A Patwardhan, M M. Alam, K K. Thatavar

A commercial wet scrubber was used in the SIU-Joy dust control laboratory to test several concepts for improving the dust control efficiency of a wet scrubber. The concepts tested included two filter-two-spray systems, hollow and full-cone sprays, horizontal and vertical sprays, different layer filters and addition of surfactant. The optimised scrubber configuration had water-only vertical sprays for pre-wetting coarse dust, and vertical surfactant-laden water sprays for wetting ultrafine particles. This scrubber configuration reduced dust concentrations from 250 mg/m3 to 1.8 mg/m3. In comparison, the conventional scrubber configuration in the feed provides an outlet dust concentration of 3 - 4 mg/m3 in field operation. Upon successful testing and optimisation of parameters in the laboratory, field demonstration of the concepts was conducted at an Illinois coal mine. The optimised scrubber configuration was tested in the field with good results in terms of improved visibility in the face area and reduced respirable and quartz dust concentrations. Additional modifications in the field involved relocation of the scrubber suction inlets from the bottom to the side and changing the water spray configuration on the miner head. These additional changes were based on a conceptualised spatial dust distribution profile in the face area. The results of these laboratory development and field demonstration studies are presented in this paper.

Jan 1, 2005

The results of laboratory grindability tests on coal are of primary importance to the designers and operators of coal grinding mills, and coal handling plants in general. However, the potential industrial application of these test results have not been fully realised due to a lack of laboratory-test/field data correlations. This paper focuses on the grindability characteristics of Queensland coals, and provides a new look at an old problem in terms of (i) a more rigorous characterisation of the grindability properties of coal and its associated mineral impurities, and (ii) the correlation of laboratory grindability test results with the size characteristics of run-of-plant thermal coals, and their pulverising characteristics in full-scale mills. A new grindability test is also proposed based on the Yancey, Geer and Price laboratory abrasion-test mill.

Jan 1, 1991

By Noakes M. J

Research and development into alternate gold and precious metals adsorbents has resulted in the development of a new technology named the AUROSAVE adsorption process (ARGOSAVE'" for high silver con- tent ores). Adsorbents called VITROKELE'" can be tailored for either Gold I (cyanide leach) or Gold III (halide leach) applications. VITROKELE consists of a chemically synthetic adsorbent carried on an inert substrate, often a polystyrene bead. It is suitable for both in- pulp and in-solution use. VITROKELE adsorbent offers certain advan- tages over both carbon and ion exchange resin adsorbents. This paper describes testwork on Australian ores and commercial solu- tions obtained from operating Australian plants demonstrating the kinetic loading characteristics, elution methods and other operating parameters of VITROKELE adsorbent in the cyanide system. Brief reference is made to VITROKELE in the Gold III system.

Jan 1, 1988

By Coulborn W. T, Glasby G. P, Maylan M. A

Research cruises by HMNZS 'Tui' (1986) and RV 'Moana Wave' (1987) investigated the geology, geophysics and seafloor mineral resources of Manihiki Plateau in the central Pacific Ocean.Manihiki Plateau is a large (500,000 km2) mid-ocean platform that rises 3000 m above the abyssal plains of surrounding ocean basins (depth -5500 m). Its foundation evolved about 112 Ma ago by massive outpouring of basaltic lavas at a plate triple junction. The plateau is blanketed by a 900 m thick sedimentary section comprising (i) mid-Late Cretaceous volcaniclastic sandstones / siltstones grading upwards to limestones / chalks and (ii) -500 m of Tertiary nanno-foram chalks and oozes. Cores from DSDP 317 drill-site on the Manihiki High Plateau indicate that the volcaniclastic sediments contain native copper and some thin beds rich in organic carbon.

Jan 1, 1990

With some notable exceptions, marine placers located just below, or just above, present sea level, are responsible for much of today's production of detrital ilmenite, rutile, zircon, and other minerals of value. The purpose of this paper is to discuss the paleogeographic and paleo-oceanographic factors which may have determined the location of presently submerged marine placers. These factors-include changes in sea level, burial by recent marine sediments, stream capture and other i changes in drainage patterns, and recent changes in climate. Selected geologic situations in the Yellow Sea off the coast of Korea, in the Atlantic Ocean off the coast of Portugal, in the Bering Sea off the coast of Alaska, and in the Arabian Sea off the coast of India, will be used to illustrate the author's point of view.

Jan 1, 1980

A portable surface impedance meter has been tested extensively over a wide variety of geological formations both in Australia and elsewhere. It has proved a useful geophysical too] for relatively shallow mapping (i.e less than 100 metres depth) of faults, intrusions, dykes and conductive ore veins and can be used as a depth probe for overburden and glacial ice. Case studies involving coal seam mapping at Collide (Qld. Australia), galena ore vein location at Zeehan (Tas. Australia) and glacial ice probing on the Brewster Glacier (South Island, New Zealand) are detailed. The first results of a similar unit using a lower frequency with consequential increase in depth of penetration will be presented. The application of VLF measurements to monitor blasting in mines and in the location of earthquake epicentres will also he introduced.

Jan 1, 1987

By Huber A. L

Research and development into alternate gold and precious metals adsorbents has resulted in the development of a new technology named the AUROSAVE adsorption process (ARGOSAVE'" for high silver con- tent ores). Adsorbents called VITROKELE'" can be tailored for either Gold I (cyanide leach) or Gold III (halide leach) applications. VITROKELE consists of a chemically synthetic adsorbent carried on an inert substrate, often a polystyrene bead. It is suitable for both in- pulp and in-solution use. VITROKELE adsorbent offers certain advan- tages over both carbon and ion exchange resin adsorbents. This paper describes testwork on Australian ores and commercial solu- tions obtained from operating Australian plants demonstrating the kinetic loading characteristics, elution methods and other operating parameters of VITROKELE adsorbent in the cyanide system. Brief reference is made to VITROKELE in the Gold III system.

Jan 1, 1988

A zone rich in-fish debris in the Rolling Dow= Group in the sub-surface of the Great-Artesian Basin has been discovered a Further research has shoe i this zone to-be of very wide distribution in the Artesian Basin and to occur. at the base of the Ta?nbo .f ormati'on resting on the Roma forma-tion. The zone gives a very characteristic curve on the electric and' gamma ray logs and is thus an excellent correlation marker in the sub-surface over a very wide area. It is probably to be correlated sith.the Toolebuc member described from: outcrops east of Boulia. There .are apparent similarities between the Fishecale zone of the Great Artesian Basin in' Australia and the Fishscale sand of the Western Canada Sedimentary Basin.

Jan 1, 1962

By Heinrich CA, Wall VJ, Walshe JL

The Porgera Gold Mine, located in the highlands of Papua New Guinea, has produced over 5 million ounces of Au, since its opening in late 1990. The deposit is located within Upper Cretaceous Papuan Platform sediments approximately 25 km south of the Lagaip Fault, and is spatially and temporally associated with the 6 Ma alkaline Porgera Intrusive Complex.

Jan 1, 1995

By Voorhees JS, Bureau G

To operate a mine in California requires compliance with State environmental regulations, including assessment of risks and associated financial assurances for postulated worst case catastrophic event scenarios. Carson Hill Gold Mine, an open pit, heap leach operation, completed new risk assessment catastrophic event analyses in 1988. The risk assessment was performed at the same time that a new leach site (Leach Site 3) was being designed. Leach Site 3 is located about 400 m upslope of New Melones Reservoir, which is a public recreation facility and a source of drinking water. Release of leachate (pregnant solution) or ore containing cyanide and metals from Leach Site 3 into New Melones Reservoir was considered to pose the largest risk of environmental damage.Flow failure of the ore heap, potentially induced as a result of liquefaction of the saturated portion of the ore, and/or overtopping of the leach site containment embankment due to excessive precipitation were found to be the most plausible leachate release scenarios. Yearly combined probabilities of various downstream release volumes were estimated. The release volume corresponding to a yearly probability of 0.05 percent was then used to estimate potential environmental impacts and mitigation costs. The costs include earthwork to restore the geometry of the ore heap and repair the fill slope below the Leach Site 3 containment, and impacts on New Melones Reservoir.

Jan 1, 1990

Stress Mapping Technology is aproprietary technique developed to target epigenetic mineralisation located in dilatant (low stress) sites. It is a computer based technique, based on rock mechanics principles and stress-strain relationships, which seeks to transform strain data, in the form of a solid geology map, to stress data.The main assumptions in the conceptual model are that:The strain pattern of faults and lithological contacts have not been changed since mineralisation i.e. that ore formation is late in the structural history.Stress orientations and magnitudes are known.Rheological properties of faults and rock units can be deduced.The 2D geometric and rheological data is then treated by a mathematical technique which permits the geometry of the elements to be defined by the spacing and orientation of the discontinuities in the rock mass.

Jan 1, 1990

By A Lim

"As Abel Mine continues to expand and increase production, the requirements of the ventilationsystem have also increased. This paper will outline the stages undertaken to increase the AbelMine ventilation system from an operating position of 110 m3/s and 500 Pa to the current operating position of 220 m3/s and 1.6 kPa and outline steps to be taken to ensure all future requirements will be able to be ventilated."

Jun 1, 2012

By G Guy, J Summerville

Over the past five years in coalmine slope evaluation the application of 3D modelling has increased significantly as software has become more user friendly but also areas requiring evaluation have become increasingly complex. Often simplistic 2D Limit Equilibrium modelling and analysis has been poorly used to solve slope stability issues by back analysis and subsequent forward predictive analysis. A plane strain condition with slope movement perpendicular to the slope strike is assumed where in reality the problem is more complex. This often leads to a misinterpretation of the failure mechanism because the failure mechanism being modelled in 2D does not generally represent the actual failure mechanism observed in the pit, with 2D modelling often oversimplifying a slope. This paper presents a case study where the initial slope assessment and remedial design evaluation was undertaken as a 2D Limit Equilibrium model which led to an overly conservative and costly remedial solution being implemented. Subsequent modelling of the slope using both 3D Limit Equilibrium and Finite Element methods were able to provide a better understanding of the structural complexities associated and correlate well with slope monitoring data to create a more realistic outcome.

Nov 29, 2022

According to our experimental results, the following oxygen probe recommended, that is, the magnesia stabilized zirconia was employed as a solid electrolyte and Fe.FexO solid elect- rode was used as a reference electrode. Using such an oxygen probe, we tried to measure the oxygen potentials in molten metals, mattes and gases in the following fields of non-ferrous metal industry, molten copper in the side launder before casting, molten crude lead in the forehearth of ISP blast furnace, molten copper mattes in the forehearth of blast furnace and in the settler of flash smelting furnace, gas in the settler of copper flash smelting furnace and flue gas in the electric furnace for ferro-silicon. In the past ten years or so, many experi- mental results in the field of fundamental studies have confirmed that the equilibrium oxygen potential could be measured conveniently and accurately by an electrochemical method using a zirconia solid electrolyte. Recently, such an electrochemical technique has been also applied to a device for physicochemical invest- igation or process control in the non-ferrous metal industry. Such a device consists of an oxygen con- centration cell with stabilized zirconia, and it is commonly called an "oxygen probe" or "oxygen sensor".

Jan 1, 1980

By Carroll D. A

The mining and minerals industry has had and will undoubtedly continue to have a considerable impact on the development of this State. For the first 60 years of its history the colony of Western Australia made slow progress; its population in 1889 being only 43,000. However, as a-result of discovering gold at Coolgardie and Kalgoorlie the Eastern Goldfields alone had a population of 25,000 by 1897. The income generated by the gold mining industry allowed the Premier of the day, Sir John Forrest, and his Government to support the proposal put forward by the State's Engineer in Chief, C.Y. O'Connor, to construct a pipeline to carry water from the Darling Ranges to Kalgoorlie ; a distance of 600 kilometres. The demand for people knowledgeable in the science and art of mineral exploitation also prompted the State Government to establish a School of Mines in the Goldfields in 1902, where it has remained ever since. The gold mines of this region have been a major source of employment for over 70 years and there is no doubt of the fact that their continued prosperity minimised the effect of the world recession on Western Australia in the 1930's.

Jan 1, 1979